NYT, Robert F. Kennedy Jr., and David Crane have no clue about how grid tied solar power actually works with the grid

Hurricane Sandy seems to have brought out the latent stupidity in just about everyone in their zeal to get in on the climate alarm resurgence. I laughed out loud when I read this op-ed in the NYT by DAVID CRANE and ROBERT F. KENNEDY Jr. published, December 12, 2012, because it becomes immediately obvious that these two “experts” don’t have a clue about how grid-tied solar actually works, and their ideas actually can cause deaths, injury, and additional property destruction if people try to follow their lead and then try to circumvent safety features when they find out their solar system won’t do what they claim. How embarrassing for them.

Excerpts:

Solar Panels for Every Home

[...]

Residents of New Jersey and New York have lived through three major storms in the past 16 months, suffering through sustained blackouts, closed roads and schools, long gas lines and disrupted lives, all caused by the destruction of our electric system. When our power industry is unable to perform its most basic mission of supplying safe, affordable and reliable power, we need to ask whether it is really sensible to run the 21st century by using an antiquated and vulnerable system of copper wires and wooden poles.   

Some of our neighbors have taken matters into their own hands, purchasing portable gas-powered generators in order to give themselves varying degrees of “grid independence.” But these dirty, noisy and expensive devices have no value outside of a power failure. And they’re not much help during a failure if gasoline is impossible to procure.

Having spent our careers in and around the power industry, we believe there is a better way to secure grid independence for our homes and businesses. (Disclosure: Mr. Crane’s company, based in Princeton, N.J., generates power from coal, natural gas, and nuclear, wind and solar energy.) Solar photovoltaic technology can significantly reduce our reliance on fossil fuels and our dependence on the grid. Electricity-producing photovoltaic panels installed on houses, on the roofs of warehouses and big box stores and over parking lots can be wired so that they deliver power when the grid fails.

That last sentence in bold is my emphasis, because it shows just how clueless these people are when it comes to real world solutions. They want to give readers the impression that they can use their grid-tied solar power system after a storm to get electricity, I’m here to tell you that claim is absolute bunk.

Full disclosure. I have a grid tied solar power system on my home. I had one on my previous home, and I orchestrated the first ever solar power system for our local school district. I know a thing or two first hand from an engineering and use standpoint. Here’s my current home installation:

IMAG0430

IMAG0431

Top: the solar panels. Bottom: the DC to AC inverters and the grid tie and SmartMeter.

Note the red labels, particularly under the SmartMeter. They are required by law. The red one under the meter (along with the new yellow one added by the utility company after inspection for the grid tie certification) reads:

IMAG0283

“Possible danger of electrical back feed” is the key phrase, one completely lost on the NYT, Kennedy, and Crane.

The issue is this, if you have grid tied power sources running in your neighborhood, and they are producing power, anyone who isn’t careful doing electrical work could get electrocuted thinking that after they pulled the main breaker, there is no power in the wires. Imagine if you have a bunch of these pumping power into power poles laying on the street after a storm; it becomes an instant fire starter.

But that’s been taken care of too, because the DC to AC inverters won’t function due to this (also required by law and code) safety feature built in.  Here’s the relevant code from the inverter installation manual:

Electrical conformity according to U.S., Canadian and
international safety operating standards and code
requirements:
– UL 1741 – Standard for Inverters, Converters, and
Controllers for Use in Independent Power Systems

And this:

4.2 Protective concepts
The following monitoring and protective functions are
integrated in blue planet inverters:
– BiSI grid monitoring to protect against personal
injuries and avoid islanding effects according to UL 1741

What is “BiSI grid monitoring”? According to E DIN VDE 0126, which is a year 1999 standard developed in Europe specifically to address the problem:

The automatic disconnection device is used as a safety interface between the generator and the public low-voltage distribution net and serves as a substitute for a disconnecting switch accessible at all times by the distributing network operator. It prevents the unintentional supply of electrical energy from the generator into a subnetwork disconnected from the rest of the distribution grid (islanding), thereby offering additional protection to the measures specified in DIN VDE 0105-100 (VDE 0105-100), 6.2 to
– operating staff, against voltage in the disconnected subnetwork
– equipment, against inadmissible voltages and frequencies
– consumers, against inadmissible voltages and frequencies
– equipment, against the feed of faults by the generator.

In a nutshell, when the power poles go down, the inverters lose connectivity to the grid, sense this automatically, and shut themselves off.

Never mind the fact that grid-tied solar power doesn’t work at night when you need it most, never mind the fact that during and after the storm, solar insolation is drastically reduced due to rain and cloudiness, and never mind the fact that all electrical systems, solar or otherwise, are just as susceptible to storm damage as conventional power infrastructure, there is one important point that kills the entire idea.

Assuming the solar panels aren’t ripped off the roof by the hurricane/storm, they are of absolutely no use because the grid-tie is broken, and the mandated grid-tie safety features prevent the homeowner from using the inverters to get power locally.

You’d think “experts” like Kennedy and Crane would understand this basic concept…but they probably never got any closer to a solar power system than a photo op.

Some might claim that a battery backup with an automatic transfer switch might solve the issue. But, battery systems double to cost of most solar installations, and need to be replaced about every four years on average (for lead acid batteries, the most common solution), and they need to be maintained, checked, etc, plus require significant space. Compare all that to a $699 generator available from a local hardware outlet that has none of these problems and you’d understand why that is currently the solution of choice for most homeowners that want backup power after a storm.

Hopefully people following their lead for solar systems won’t try to hack their solar power system inverter safety features in time of crisis.  The first person to try defeating this safety feature after a storm may get themselves or others killed or injured, either by electrocution or fire. Hopefully the solar power industry will join me in condemning this foolishness propagated by Kennedy and Crane.

h/t to WUWT reader Charles Carmichael for the NYT story link.

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140 Responses to NYT, Robert F. Kennedy Jr., and David Crane have no clue about how grid tied solar power actually works with the grid

  1. David Larsen says:

    Absolutely correct Anthony. The only option would then be use batteries for storage and then you would need to convert the DC to AC for the power availability during the black out. Use life on batteries is still 3-4 years.

  2. You might note that Mr. Crane is the president of NRG. He just might know something about this…

    REPLY:
    You’d think that, wouldn’t you? How many CEO’s can actually understand the engineering? See my reply to Brian Jay below.

    Also, do you really think Robert F. Kennedy and Crane do any hands on work/engineering so they’d understand this if in fact they have solar on their own homes? Looks to me more like Crane is pushing business in the guise of an op-ed. Must be “big solar” ;-) – Anthony

  3. BrianJay says:

    Look I don’t really worry about Kennedy electrocuting himself or the whole clan for that matter, but as an Electrial Engineer I would suggest that some way around this could be found so that if you produce it locally you should be able to use it locally. The problem to me is the same if you had a diesel powered generator in that before connecting to the grid you have to sync the freqency and the voltage output in order to make sure that you are a generator and not a load. In other words you don’t have to supply everyone else in the street should the pylons come down, just your freezer.

    REPLY: you and I can manage these things, but how about Joe Blow, homeowner under stress? Do you really trust people to be able to figure out how to connect/disconnect safely, or to evaluate if their solar system is damaged? First injury/fatality kills the idea, and I doubt any company wants the risk – Anthony

  4. Matthew W says:

    “When our power industry is unable to perform its most basic mission of supplying safe, affordable and reliable power, we need to ask whether it is really sensible to run the 21st century by using an antiquated and vulnerable system of copper wires and wooden poles.”

    Complete hyperbole.
    During NORMAL or REGULAR conditions, the electric companies do an incredibly fantastic job.

    “When our power industry is unable to perform its most basic mission of supplying safe, affordable and reliable power,”
    Well guess what, “green energy” will guarantee that situation.

  5. BradS says:

    Very interesting, thanks for the explanation. I was driving by a house with a couple large solar panels on the roof the other day. They must have been there for a while because they didn’t look like yours, the glass was all milky not black like yours. I wondered how much power they would generate at this point.

  6. As I understand it though, as long as you’re not tied to the grid your solar is usable locally. It just has to be hooked up to your house in a way similar to a generator would be so you can ‘switch over,’ the drawback being you’re pulling from the grid with the solar as a backup only system.

  7. Steve from Rockwood says:

    This is not a Joe Blow homeowner issue. These power systems are designed to generate onto an operating grid. When the grid goes down so does the power system. Other systems are designed to operate off-grid. No connection, no risk. But now people are suggesting to spend $25,000 on a home energy system because once every 50 years they will lose power for a week? It would make more sense to give people vacation vouchers and station the national guard in affected neighborhoods to prevent looting.

    The simplest way to reduce the seriousness of a post-storm crisis is to force the gas stations to have a power backup plan so they can pump fuel or replenish and a method of payment tranasction so they can sell it. Not having fuel for your car means you can’t get anywhere so you’re stuck in a house without power.

  8. john robertson says:

    More proof that one can spend their lives around a technology and know nothing.
    Careers? I hope these morons get paid what they are worth.
    Another example of the Peter Principle at work and these two are poster children for the whole Green Philosophy.I really wish they had a coherent philosophy.

  9. AC says:

    Don’t overlook the adrenaline factor of working in the dark while people are complaining about the loss of power.
    Even smart EE’s can make really big misteaks.

    Even trained EMT personnel sometimes end up measuring their own heart rate instead of the client riding the gurney in the ambulance…

  10. ShrNfr says:

    Some of what you say is correct, some is not. You have to have an outside disconnect on your system for both the grid and the panels per my electrical inspector and the NEC code. However, there are inverters that are made by folks like Outback that do grid-tie but do not need to be connected to the grid to generate electricity for local use. When the grid goes down, they pull power from a battery bank/solar panels and put out AC from their inverter port(s). Property installed, the folks on the grid side are not exposed to anything hazardous. The inverter only feeds back to the grid when the grid is within its specifications and the panels are generating more than the load on the inverter side. These, however, are not the cheap setups that are frequently flogged. Those setups usually take power from the panels at 400+ volts (roughly 15-20 panels in a string) and then grid tie with no battery. Those systems will not do anything worthwhile when the grid is down or the sun does not shine.

    Proper design of the panel mounting so that they do not get ripped off the roof is a must. I designed my system to withstand 130 mph winds in MA. Anchoring the mounting is neither cheap nor easy. You are talking major stainless steel lag bolts into substantial fir beams to anchor the tracking.

    You can partially power your own house and reduce your electricity bills with the correct type of grid-tie system, but beyond that all bets are off.

  11. techgm says:

    Pity that the article was entered as an op-ed; there is no opportunity for the nonsense to be rebutted in the NYT. (This kind of nonsense persists because it cannot be so refuted.)

    In addition to what has already been observed, if damage to the assemblage of all those wires up on all those “pitch pine poles” is the part of the electrical generation & delivery system that overwhelmingly causes outages resulting from storms, then, even if every roof generated (excess) PV power “so that they deliver power when the grid fails,” how is that power going to be distributed? The lines are down!

    Plus, if Crane & Kennedy are really so concerned about the cost of homeowners having their own “expensive” generators, just wait till they see the cost of even modest PV systems – or is the US Treasury’s tooth fairy going to pay for all that silicon and its installation? (And living in the local EconoLodge for a few weeks is also “expensive,” assuming you can find a room.)

    Lastly, they make a sneering reference to an assumed profit motive of investor-owned power companies, suggesting that those companies are really concerned about diminished profits due to power not bought by homeowners. Even if homeowners could afford to cover the entity of their roofs with PV systems, the power that they could generate would not come close to what they would normally consume, especially with air conditioners or radiant heat going, nor would not buying the equivalent power from the local utility appreciably affect the utility since industrial and public users would still be buying. Further, investor-owned utilities operate as regulated monopolies, which means their investments and rates are regulated by the regions/communities they serve, which diminishes a profit motive.

    Good grief. And one of the authors is supposed to be an industry expert?

  12. bob says:

    I’ve read about systems that do the same thing for solar that they do for home generators — they disconnect the house from the grid when the power goes out. They don’t disable the house, but isolate it. Is that incorrect? I don’t see anything in the quoted code at odds with what I’ve read previously.

    REPLY: When the grid AC power goes off, the inverters turn off, and thus no AC power is generated nor available. – Anthony

  13. Mike M says:

    “Electricity-producing photovoltaic panels installed on houses, on the roofs of warehouses and big box stores and over parking lots can be wired so that they deliver power when the grid fails.”

    Anthony, I think you’re making a mountain out of a mole hill. There’s nothing false about the statement. It isn’t a technical manuscript just a point of information – “can be wired”. They aren’t describing how to do that and certainly aren’t suggesting the homeowner do it. Most people are smart enough to leave power wiring to professionals and the ones that aren’t can be left to Darwin…

    As to safety why not just add a disconnect to the converter/meter panel(s) that interrupts both ways?

    REPLY:Point: “Electricity-producing photovoltaic panels installed on houses” seems to clearly imply homeowner to me. OK let’s assume the local big box store/warehouse has live solar power, with the power pole infrastructure wrecked, how do you propose to get that power out to the neighborhood? – Anthony

  14. Doug Huffman says:

    Lithium cells, so au courant, do have limited life time and limited use time. A lead-acid cell’s life is theoretically unlimited with intelligent use/maintenance.

    Nuclear submarines still use 126 1200# lead-acid cells per battery. They also use diesel powered emergency generators, and trained personnel

  15. Paul Westhaver says:

    Anthony,

    Wind speed, therefore wind energy as a function of hour-of-day is available. Sun intensity, therefore sun energy as a function of hour a day is also available. Demand as a function of hour of day is available and so is the existing grid supply.

    It seems to me that power grid mavins or interests woould have plotted this out already as a routine power engineering exercise.

    Here is such a curve from the netherlands:

    http://www.clepair.net/fotos/Udocurtail201205-2.gif

    and the UK:

    http://windbyte.co.uk/ims/windpower/ng_winter0910_wind_demand.jpg

    solar supply vs demand in AU:

    http://www.solarquotes.com.au/images/winter_electric_demand_nsw_sml.jpg

    This is fairly simply math if you have the data at your disposal. I suggest that this is a known ans well understood problem. Has anyone you know of plotted it? I have a feeling the reality is that wind is unreliable against demand, as is sun and the grid cannot shunt power to accomidate shifting supply and demand.

    Do you have a study on hand?

  16. Bloke down the pub says:

    When I first looked into getting solar pv, I thought it might be useful in the event of a power outage, only to discover that it wouldn’t for the reasons you state. Systems not linked to the grid are available but as David Larsen notes you then need a battery system which can be expensive and needs replacing every so often. You also lose the main financial advantage of not getting any feed-in tariff. I have wondered if a system is feasible whereby,in the event of an outage, an extra isolator could cut off the system from the grid(safe-guarding those working on it) and allowing the pv unit to work as a stand-alone. It would need to be idiot proof, as you know how clever those idiots can be. Sods law says that any power cut would be at night so the return on investment might not be too good. In the meantime I get my Fit from my panels, and keep a battery charged for back-up lighting.

  17. RHS says:

    Is this the same Kennedy who nixed off shore windmills because they blocked the view from his beach front property, his harbor, and other properties? Or was that a different Kennedy?

  18. Ken Langford says:

    I read the standard as requiring a disconnect between the home generation and the utility service, not a requirement to shutdown the home generation system as you are implying. Of course, if the home generation system cannot meet the home’s load requirements, then it would naturally disconnect due to overload.

    REPLY: That’s true, but if the home system wiring is damaged by the storm (a highly likely scenario) do you really want to risk burning down what’s left of your home by turning on your solar power system? People make generators work because those bypass the home electrical system. Direct plugs. Now I suppose if manufacturers offered a direct plug system for grid-tied inverters, it would be equivalent to a generator. I’ve yet to see one. – Anthony

  19. Doug Huffman says:

    @”I designed my system”: and your time to return investment is how long, how much longer than your lifetime? A good cost for electricity (less infrastructure costs) is ~6¢/kWh.

  20. Paul Westhaver says:

    Power Generation and delivery to load is similar to the UPS Delivery Company problem. A package can come from anywhere and the package can end up anywhere, yet they do it everyday very well.

    Seems to me that the UPS pick-up and delivery math model (which is quite a feat) should be adaptable to a chaotic wind/sun/coal/nuke power apportioning model.

    I don’t expect it to resolve the supply/demand imbalance, but it could express the enormous demands on delivery system required.

  21. polski says:

    Considering the output of roof mounted panels, what would you realistically be able to use power wise in your home assuming that the proper switches and fail safes are dealt with..Would some equipment falter if an errant cloud sauntered by?

  22. DR says:

    I haven’t seen the UPS delivery math model. Is it similar to calculate how many people it takes to produce a pencil and get it on the shelf at the Dollar store?

  23. jb frodsham says:

    Ceramic Fuel Cells: “The first marketed product of the company is “BlueGen” a solid oxide fuel cell which creates electricity and heat by passing natural gas over ceramic fuel cells. BlueGen is 85% efficient” It comes as a box, about the size of a small washing machine.

    I thought this was a great idea, So about 3 years ago I bought shares in the company. Sadly my shares are now worth 75% less of what I paid. Looks like another fail to me. Shame really, as it is a great idea.

  24. Billy says:

    Diesel and gasoline generators have governors and voltage regulators or inherently stable winding designs to allow stable independent operation. PV solar systems have no stability so they rely batteries or a grid connection to stabilise voltage. Without batteries, when load is less than output, voltage will rise out of control. When load is greater than supply voltage will drop. Either case causes damage or failure of operation. That is why your system has no isolated system option. It will not work that way.

  25. Graeme No.3 says:

    In Australia the standard installations for solar are as stated, off grid with battery storage or on grid. The latter behaves as you say; no voltage on the grid means the solar power stops. Even a power interruption will shut down the solar system, which then takes some time to reconnect.

    You can buy a system which involves another meter/circuit breaker. This does the disconnection when the grid goes down, isolating the house circuit from the grid (safety for linesmen etc.). Your solar system can continue supply (during daytime) and storage/backup is supplied by a ‘chemical’ battery i.e. one which circulates ionic fluid (usually vanadium base).
    I looked briefly at it, very briefly when I saw the cost. Still, if you are interested and have a spare $100,000… but still useless if your house is damaged.

  26. Leonard Weinstein says:

    Doug Huffman says: December 13, 2012 at 10:17 am
    “Lithium cells, so au courant, do have limited life time and limited use time. A lead-acid cell’s life is theoretically unlimited with intelligent use/maintenance.”

    NO!!! Lead Acid Batteries have a very limited cycle life under any use. My reference is the “Handbook of Batteries, Second Edition, by David Linden”. Typical good deep cycle lead acid batteries last about 500 full charge/discharge cycles. Present best Lithium cells last as long or longer, but are much more expensive. If you are referring to storage time, not use, Lithium cells are also better at that. However, they are dangerous (fire) if damaged, so limited in some uses.

  27. theduke says:

    The NYTimes is stupidly printing misinformation and dangerous misinformation at that. I think a correction ON THE FRONT PAGE is in order. They risk a lawsuit for providing incomplete and potentially dangerous information if they don’t. As do Kennedy and Crane.

  28. Frank says:

    Your post left me confused. When the power is out, does the typical installation allow a homeowner with solar panels to use electricity from solar (when the sun is shining)?

    If one is not connected to the grid due to a power outage or by design, how do solar systems handle the problems created when there is an imbalance between the power generated by the solar panels and differing power demanded by electrical devices in the home. Under normal circumstances, there will be too little or too much power. When not connected to the grid, can household equipment be damaged and/or safety compromised when the power spikes or drops due to changing cloud cover?

  29. Paul Westhaver says:

    Anthony says:
    REPLY: That’s true, but if the home system wiring is damaged by the storm (a highly likely scenario) do you really want to risk burning down what’s left of your home by turning on your solar power system? People make generators work because those bypass the home electrical system. Direct plugs. Now I suppose if manufacturers offered a direct plug system for grid-tied inverters, it would be equivalent to a generator. I’ve yet to see one. – Anthony

    __________________________________________________

    I know of a small Massachusetts company that made a power management system for the home solar/wind/grid market. They made a working device that handled the power from the utility AND home generated power. This was done 3-4 years ago in response to the huge government handouts for installers of solar and wind.

    Solar Sheds was the company I think.

  30. Doug Huffman says:

    Oh, show your work.

    @”I designed my system”: and your time to return investment is how long, how much longer than your lifetime? A good cost for electricity (less infrastructure costs) is ~6¢/kWh.

  31. theduke says:

    [SNIP - I can't substantiate that claim, so can't print it due to potential legal issues, sorry - Anthony]

  32. davidmhoffer says:

    These folks aren’t as dumb as many seem to think. An article like this gets voters and politicians (who don’t understand the issues) asking “hey, why aren’t we doing this?” The questions trickle down to regulators and departmental administrators (who don’t understand the issue) which gets more questions trickled down to some level where the issues are understood and the answers come back in laymen’s terms like “there are a lot of design considerations we’d have to look at”.

    Followed of course by some politician asking “well, how much would it cost to do that?”

    Hook set, real ‘em in. Grants for studies, grants for proof of concepts, subsidies to make it viable “to get it going and then after a while the subsidies aren’t needed anymore”. LOL, yeah right.

    And what sorts of companies have the skills to do these sorts of studies, proofs of concepts, or build out the systems that would be eligible for the subsidies?

    The bait is cheap. If nothing comes of this, they lost only the time to write the article. If they do hook something… well, let’s just say they’re not fishing for perch.

  33. Bill Taylor says:

    our generator has a switch that unhooks the grid when it is running(except during its exercise run for 10 minutes weekly), when the grid power comes back the switch reverses the process and reconnects to the grid…..when we lose power it takes a minute before that switch acts.

  34. jmdesp says:

    @RHS : Well, one thing is sure, it’s the same Kennedy who boasted to gas executives than renewables would greatly help them sell more gas plants :http://www.youtube.com/watch?v=qcm1gmPL50s

    Which was wrong by the way, solar eats gas lunch in mid-day, and coal is not as bad as many thought at load following. For coal that’s already built, given how much cheaper the fuel is, even being a bit inefficient because of the load following still keeps it much cheaper than gas, so it’s used before gas.

  35. MarkW says:

    “Having spent our careers in and around the power industry”

    What does this mean? That they can see power lines from their front porch?

  36. MarkW says:

    Paul Westhaver says:
    December 13, 2012 at 10:18 am

    I don’t see anything in your curves to account for the random cloud or rain storm.

  37. Dennis Cox says:

    Your grid tie concerns are valid. But it’s not a complicated engineering problem to design and build a grid safe system. I designed mine too. And I can disconnect from the grid, and run completely indepndant of the power company at any time. Our solar panels provide more than enough power to run the house during the day as well as charge a battery rack consisting of 30 24 volt Ni-Cad aircraft batteries that carry us through the night. In fact the only reason we remain connected to the grid is to provide a backup if I should need to do maintenance on the solar system, or if there’s a problem with the inverters. Here’s one of two solar racks on the property. http://dl.dropbox.com/u/2268163/SolarShade.JPG Happiness is being able to tell the power company to put their ‘Smart Meter’ someplace the sun doesn’t shine

  38. RockyRoad says:

    They could always bury the copper and use steel poles instead of wood where necessary, but that would drive electricity rates up and beyond acceptable levels.

    So that’s the quandry–paying for a “what if”. And because our “climate scientists” can’t forecast when any particular event will occur and what the problem will be nor the magnitude, it’s a perpetual guessing game.

    But politicians love perpetual guessing games–nobody can hold them accountable for anything, yet they will claim all the credit but take none of the responsibility.

  39. john robertson says:

    @ jmdesp 11:02am Wind and solar do sell more gas, gas turbines being the fastest backup power available when the clouds blow in or wind stops/blows too hard.
    Conventional heat plants are more efficient but cannot be brought on line as quickly.
    Not new was well known in 1970s when I worked in Power Generation.

  40. Scottie says:

    As an (amateur) astronomer I chuckled at this comment by Anthony:

    …when they find out their solar system won’t do what they claim

    Bring on the Vogons – they’ll sort out the solar system!

    (With apologies to Douglas Adams) and…
    /sarc – for those in the western hemisphere

  41. Gunga Din says:

    ““Possible danger of electrical back feed” is the key phrase, one completely lost on the NYT, Kennedy, and Crane.

    The issue is this, if you have grid tied power sources running in your neighborhood, and they are producing power, anyone who isn’t careful doing electrical work could get electrocuted thinking that after they pulled the main breaker, there is no power in the wires. Imagine if you have a bunch of these pumping power into power poles laying on the street after a storm; it becomes an instant fire starter.”
    ===============================================================
    I remember 20+ years seeing a electrical safety demonstration. They took one of those transformers that are commonly seen on light poles and plugged the “house side” into a regular 120 volt power socket. They then put a hot dog on the supply side (the grid side) of the terminals and fried it to charcoal in seconds.
    If you have a home generator without some automatic switch to cut of the power to your home from the grid, be sure to remember to throw the main breaker in your home before cranking up the generator. Perhaps add your own reminder to the pull cord or gas tank? Power will be restored to your home much faster if you’re not complicating the situation for the workers or even killing them.
    Having light in your home isn’t worth a life.

  42. jeez says:

    jb frodsham

    Haven’t looked up BlueGen or their fuel cells, but if a significant part of the 85% is the heat, you’ll find it’s very efficient to simply burn Natural Gas when it comes to heating.

  43. Agreed, Kennedy and Crane don’t know what they are talking about. On the other hand, I’ve had a solar installation for a few years, just an ordinary grid-tied one.It basically zeros out our electric usage for the year. Last year we generated about 250KWh mor than we used and the power company sent us a check for $7.76. Typically solar produces the most power on bright sunny days, which are the same days that the AC runs. It’s worked very well for levelling electric usage in the summer. As “green” benefit, that can’t be bad for the power company since it reduces the peak load a bit.

    On the minus side, I have to thank you all for helping to pay for it. Various tax credits, federal, state, and from the power company paid for $13000 of the cost. Along with Solar Renewable Energy Credits, mandated in PA for generation companies, which bring in around $1000 a year our return on investment has been about 6%. One of those uneconomic fovernment mandates that have raised the cost of electricty. Even without the subsidies I would have gone ahead with it anyway. The ROI would have been about 2%, but at the time, and for the forseeable future that looks pretty good.

  44. Kev-in-Uk says:

    Dennis Cox says:
    December 13, 2012 at 11:16 am
    correct – that is of course, the entire benefit of a battery based storage/retrieval system – as opposed to a simple ‘smartmeter’ type direct in/out system.
    .
    Frank says:
    December 13, 2012 at 10:50 am
    most solar or wind systems have some kind of dump load to dispose of unwanted energy when in ‘direct’ supply mode – effectively just a big resistor (like an electric fire)

    I’m not sure that the original reference to supplying power to the grid is more intended to refer to folks’ solar systems being used to repower a local grid? If a local substation system was in good condition (i.e not damaged) and could be isolated form the main grid – it may be feasible for a local temporary supply to be established from wind/solar sources ‘within’ the mini-grid? – Of course, this would require a degree of safety features to ensure folk know that after a main grid failure, the local system could ‘become’ live again!

  45. Paul Westhaver says:

    mark w…

    exactly.

  46. Day By Day says:

    I currently own two solar homes–one in Utah, not grid tied and one in AZ that is grid tied–so I know of what I speak. It is not the cost that stops people from producing their own when the grid goes down, it is the electric company. The true cost of setting up a system is less than a car–but the government substadies has had solar companies inflate the price because of the money owners get back. It makes me sick–my totally independent state of the art totally automatic (including geneator backup) only cost $17,000 to run my whole house–I put it in with a neighbor. In AZ I have 20 panels with NO batteries and no back up and it cost $27,000–but it was installed by a “green” solar company and I will NEVER do that again.

    The article says, Some might claim that a battery backup with an automatic transfer switch might solve the issue. But, battery systems double to cost of most solar installations, and need to be replaced about every four years on average (for lead acid batteries, the most common solution), and they need to be maintained, checked, etc, plus require significant space.

    BrianJay says: I would suggest that some way around this could be found so that if you produce it locally you should be able to use it locally. You would think so, and morally it SHOULD be so, but you’d be wrong in most cases.

    Anthony answers Do you really trust people to be able to figure out how to connect/disconnect safely, or to evaluate if their solar system is damaged? First injury/fatality kills the idea, and I doubt any company wants the risk

    Anthony is right, companies will NOT let you produce your own in most cases.

    nuclearcannoli says: As I understand it though, as long as you’re not tied to the grid your solar is usable locally. It just has to be hooked up to your house in a way similar to a generator would be so you can ‘switch over,’ the drawback being you’re pulling from the grid with the solar as a backup only system.

    Mike M says: Anthony, I think you’re making a mountain out of a mole hill. There’s nothing false about the statement. It isn’t a technical manuscript just a point of information – “can be wired”.

    nuclearcannoli and Mike M–the electric companies will NOT let you hook up any more–they used to but now they catagorically say NO. I can’t even get past the receptionist in Arizona for Unisource–they say you cannot have a back up system period! They will not even talk to me about any solution whatsoever–if the grid goes down, I go down.

    I am quite sure this is not legal and I will petition my legislators to make a law saying we can be independent (I hate regulating companies but it is sooo unreasonable)– after I complain to every government department I can find. I am so furious about this–I would have put in my own system if I had known–which no one tells you at installation–the liars at Mohave solar told me we could talk about having a back-up for solar after they put it in the way the electric company wanted it–Well, I guess it was not a lie–we could “talk” about it–its just that I can’t do it no matter how much we talk. I called them to ask about it after installation and they blew me off…they got their subsidies and I got (self-snip).

    Yes, with proper installation it would free up a lot of grid dependence and it can be done and for a lower price than claimed–the new technology is fantastic–so now we have to FORCE electric companies to let us keep locally what we produce locally–ie in our homes.

  47. Philip Peake says:

    There are lots of books and “experts” that will tell you that lead-acid batteries have a life expectancy of three or four years. However, that is for a specific style of battery, basically the sort that you get in your car.

    These are really quite high tech, with the plates being fabricated to allow fast charge/discharge and working over a wide temperature range, to say nothing of standing up to vibration.

    Being a somewhat ancient specimen, I remember visiting a telephone exchange when I was fairly young. Ths was when the phone system in the UK was run by the GPO, who were (at that time) more interested in proper engineering than making a profit. The exchange was a wonderful place with rack after rack of uniselectors and relays clicking and whirring, connecting and disconnecting calls. They also showed me a large dynomotor — an electric motor which also has windings and commutators – plural in this case and windings to generate electricity. This used to be how high voltage was generated for valve/tube radios, the motor being 12 or 24 volt, and the generator sections delivering 250v and a 6.3v for the valve/tube heaters.

    Anyway, this version was driven by 48v DC (if memory serves) and the generator windings generated the different AC waveforms for all of the tones you heard (dial-tone, busy tone etc).

    Everything in the place basically ran from 48v DC.

    The next part of the tour was the battery room. It smelled of fizzing sulphuric acid , and the battery cells were probably 4′ tall and 2′ square. Each one a single 2.2v lead-acid cell. The batteries would continue to power the entire exchange for two weeks if power was lost.

    The plates in the cell were huge, and took two people to lift one out. The person tour explained that over time, the plates tended to sulphate up, so every six months or so, on a rotating basis, a cell would be taken out of service, and physically scrubbed to remove the sulphate build-up. The electrolyte adjusted by adding acid or distilled water as appropriate, and the cell placed back into service. Some of those cells were 20+ years old.

    You can get (or could) long lasting lead-acid cells, but they are big for a given capacity, and require regular maintenance.

    Probably not for your average consumer — but certainly not impossible.

  48. theduke says:

    Anthony: re my post at 10:53 am:

    From a transcript of the Oprah show:

    Oprah: I know you became an environmental advocate after beating a heroin addiction. How did you get hooked?

    Bobby: Pretty soon after my dad died, I started taking drugs. I was part of a generational revolution that looked at drugs almost as a political statement—a rebellion again the preceding generation, which had opposed the civil rights movement and promoted Vietnam. At the time, I don’t think any of us were aware of how damaging drugs could be.

    Oprah: When did you first know you were in trouble?

    Bobby: When I was a kid, I’d always had iron willpower and the ability to control my appetites. At 9 I gave up candy for Lent and didn’t eat it again until I was in college. After I started taking drugs, I earnestly tried to stop. I couldn’t. That’s the most demoralizing part of addiction. I couldn’t keep contracts with myself.

    Oprah: I think every addiction is a cover for an emotional wound.

    Bobby: I’m not sure if I agree with that. I don’t know whether addiction is principally genetic, a result of emotional injury, or a combination of both. But all that matters is what I do today. Insight doesn’t cure the addict any more than insight cures diabetes. You may understand perfectly well how diabetes works, but if you don’t take your insulin, you’re dead. The same is true with addiction. It doesn’t matter what got you there; it’s how you conduct yourself today, day by day.

    Oprah: Once you broke the habit, did you still crave heroin?

    Bobby: No. I’ve been sober for 23 years, and I’m one of the lucky ones: I’ve never had a single urge since. Once I completed a 12-step program, the obsession I lived with for 14 years just lifted. I would describe it as miraculous . . .

    I knew I was close to the edge with that post, but his habit is well-documented, as is his recovery. Pity he couldn’t do anything for his wife.

  49. Chris @NJ_Snow_Fan says:

    My neighbors house has a $90,000 dollar solar system that was installed 4 1/2 a years ago. The state of New Jersey paid $45,000 dollars half the cost of the system. In the past 2 years the power went out two times, between 5 to 10 days and he was without any power or able to produce any power back into the grid for tax credits during that time. If he had an off grid system with batteries he would have had power.

  50. RS says:

    To be fair, there ARE grid interactive inverters out there that are grid tied when the grid is up and safely isolate the home power bus inverters for continued low power PV/Battery use when the grid is down. Outback Power makes one called FlexPower

    These systems are much more expensive than the grid tied inverters normally used and virtually no one uses them save preppers and people with very tenuous grid ties in the woods.

  51. MattS says:

    @Paul Westhaver

    “Power Generation and delivery to load is similar to the UPS Delivery Company problem. A package can come from anywhere and the package can end up anywhere, yet they do it everyday very well.

    Seems to me that the UPS pick-up and delivery math model (which is quite a feat) should be adaptable to a chaotic wind/sun/coal/nuke power apportioning model.

    I don’t expect it to resolve the supply/demand imbalance, but it could express the enormous demands on delivery system required.”

    Except the supply/demand imbalance is everything for the power grid.

    Power In must equal Power Out on a sub-second basis or something somewhere will explode.

    Any solution for handling chaotic generation at grid scale must solve supply / demand balancing in real time or it’s useless. This is why grid scale wind/solar installations require full nameplate capacity spinning reserve backup from fossil sources.

  52. Streetcred says:

    Kennedy should stick to bootlegging, they were at least good at THAT !

  53. DirkH says:

    Billy says:
    December 13, 2012 at 10:46 am
    “Diesel and gasoline generators have governors and voltage regulators or inherently stable winding designs to allow stable independent operation. PV solar systems have no stability so they rely batteries or a grid connection to stabilise voltage. Without batteries, when load is less than output, voltage will rise out of control. ”

    It would be possible to program an inverter’s DSP in such a way that even in the absence of batteries it could build up a micro grid (for one household) as long as available solar power is bigger or equal to the load.

    The inverter stores a small amount of energy in capacitors and inductivities; and can shift the power point (power = voltage times amperage) into “bad” territory when too much solar power is available.

    In practice, this would result in a smaller duty cycle for the IGBT’s (semiconductor switches that switch on and off thousands of times a second) on the incoming end. (they’d be “ON” for a smaller percentage of time.

    So, it would be doable. The digital signal processors can stabilize the inverter under these circumstances. Nobody would really design something like that without a battery though – as your intent would be to maintain a micro grid when the main grid goes down, you would obviously add a few bucks worth of battery at least. After all, the solar panels and inverters already cost some tens of thousands of Dollars so it would be very stupid not to add batteries.

  54. Ed Darrell says:

    Anthony, do you have an emergency generator, too? Is it similarly disabled in event of grid shutdown?

    REPLY: No, I don’t. But my home has underground power service and we don’t have hurricanes or much in the way of tornadoes here – A

  55. Willis Eschenbach says:

    Matthew W says:
    December 13, 2012 at 9:39 am

    During NORMAL or REGULAR conditions, the electric companies do an incredibly fantastic job.

    During NORMAL or REGULAR conditions, everyone does a good job. What counts is not that, that’s the ground state, you damn well better be able to handle that.

    What counts is how you do when the excrement intersects with the air-circulation device … and in that regard, some electric companies do better than others.

    w.

  56. RobertInAz says:

    David Crane’s company – NRG is the largest operator of nuclear power plants in the USA. It also owns more solar capacity than any other company. NRG owns the solar panels on my roof.

    I agree with others that they have glossed over the details. Some things I would be interested in:
    – Is the notion here to create smaller grids (perhaps at the substation level) where solar capacity could be shared within that grid?
    – Would these smaller grids manage energy storage and possibly provide local backup capacity?
    – Could a local grid operate intermittently (many places in the world get power for a few hours a day)?
    – How would a local grid shed load? For example – could air conditioning be turned off but refrigeration be supported?

    I disagree with their assertion that the economics pencil out. It probably works in Arizona with its expensive electricity. It appears to me that they have not priced in the paradigm shifts and required non generating infrastructure investments to make this notion work. At least not with natural gas at current prices.

  57. Dan in California says:

    From the article: “by using an antiquated and vulnerable system of copper wires and wooden poles.”

    This was my first indication these people have no clue. The grid stopped using copper wire decades ago. It’s all aluminum now. I have a small PV array and enough batteries and inverter to run my refrigerator in the event of grid loss. But I live in the desert, where weeks of no sun are not likely, and I have a backup backup in the form of being able to charge the batteries from my car.

  58. Rosco says:

    When the grid power goes off the Inverter no longer transforms the 12 V DC to 110 or 240 V AC.

    What use is 12 V DC when trying to run your fridge, washing machine, stove, TV, computer etc ?

    The only way to make solar “stand alone” is to have battery supply to run the Inverter – then the system can run whilst there is charge in the batteries.

    Such systems are prohibitively expensive and usually are only viable where there is no grid supply.

    My sister lived with such a system for years and let me tell you if she could have had the grid supply she would have jumped at it.

  59. Marine_Shale says:

    Hi Anthony
    Nedap, a Dutch company make the PowerRouter inverter that has “Island Mode” which isolates the grid but maintains power to the house (and a battery bank if you have one) in the event of a power outage.
    I nearly bought one for my 5 Kw system in Cairns (Aus) but they were about $6000
    so I got the standard inverters instead. Look up PowerRouter on Google, very impressive.

  60. Gail Combs says:

    BrianJay says: @ December 13, 2012 at 9:35 am
    …..

    REPLY: you and I can manage these things, but how about Joe Blow, homeowner under stress? Do you really trust people to be able to figure out how to connect/disconnect safely, or to evaluate if their solar system is damaged? First injury/fatality kills the idea, and I doubt any company wants the risk – Anthony
    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    In answer to the question
    “Do you really trust people to be able to figure out how to connect/disconnect safely, or to evaluate if their solar system is damaged?”

    The answer is not no, it is HELL NO!

    We live in farm country and I can not tell you how many friends and neighbors have come to my husband (physicist) to help them get a very simple electric fence wired correctly.

    I can not think of anything in electricity that is simpler except maybe plugging in an electric cord, but the creative ways it gets mucked-up is truly incredible.

    For those not familiar with electric fences:
    The circuit is from a copper ground rod driven ~ 6 ft into the ground connected via an insulated wire to the clearly labeled terminal on the box. Then from the other terminal (also clearly labeled) a second insulated wire goes to the electric fence wires (naked) mounted on insulators.

    Plug in the box and the check light should blink. Fence testers can be used to check the actual fence too.

    Much much better that people use the diesel or gas generators and just plug in what they want to run. There is normally plenty of time to stock-up on diesel or gas. If you are living in an area prone to flooding then you best bet is to get the heck out of dodge until the storm is over.

  61. NoAstronomer says:

    I have no comment on the praticability or safety of the proposed installation.

    However, as a resident of coastal NJ who lost power for a little under 7 days during the recent … ‘event’, I would like to point out that solar panels were essentially useless for about two weeks afterwards.

    The sky was completely overcast for about a week, so no power for that week, and then we had foot of snow which took another week to melt. My neighbour across the street has a solar installation and his little generator was up and running *before* the storm hit.

    Mike.

  62. Doug Huffman says:

    Read N. N. Taleb on the differences in the learning of doers and writers. He teaches also the differences among fragile, robust and anti-fragile. Infrastructure varies between fragile and robust, as Fukushima Daichi was robust to the expected stressors.

  63. ntesdorf says:

    Totally correct analysis, Anthony. The Solar Cells on our roof work in exactly the same way and cut off when the mains supply stops. They save us about $400 a year, but that’s it. They don’t work in the dark!

  64. Gail Combs says:

    RHS says:
    December 13, 2012 at 10:21 am

    Is this the same Kennedy who nixed off shore windmills because they blocked the view from his beach front property, his harbor, and other properties? Or was that a different Kennedy?
    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Nephew.

    He is son of Robert F. Kennedy. (he had 11 legitimate kids) He is the nephew of President John F. Kennedy and Senator Ted Kennedy.

    …. Senator Kennedy's accomplished commitment to environmental causes remains an indelible part of that legacy. In spite of (or perhaps "because of") his environmental advocacy, the Senator opposed a prominent clean energy project; one that would have supplied his home state with 10% of its electricity needs without carbon emissions and offset the use of a carbon-intensive power plant. The Cape Wind Energy Project (Cape Wind), intended for Nantucket Sound (4-11 miles offshore from Massachusetts' Cape Cod), is a controversial offshore wind farm; the 130-turbine farm was first proposed in 2001, but as of late 2009 the wind farm remains mired in regulatory limbo. Since Cape Wind is the nation's most prominent and most advanced offshore wind farm proposal, the fate of Cape Wind will have direct impact on future interest in offshore wind development. As several newspapers have noted, the Senator's passing may influence the future of one of the most significant energy projects in American history, after his years advocating political and regulatory delays. However, to suggest that merely without Senator Kennedy's opposition, Cape Wind will succeed, is to underestimate the regulatory impediments.

    http://www.vjel.org/news/NEWS100203.html

  65. Kiwisceptic says:

    Anthony is absolutely correct! Anyone who works in the solar power industry, as I do, should know these basic facts. The safety features pointed out by Anthony are crucial to any such installation. The company I work for installs 2kW to 3.8kW and soon, 5kW, solar inverters all over the world. It’s standard practice (http://www.enatel.net/).

  66. Peter C. says:

    Most boats now have a combination Inverter/battery charger with transfer switch/relay.
    While you have shore power,batteries are being charged and DC loads are supplied by the charger.
    Lose shore power and the transfer switch cuts of the shore power plug and turns on the inverter.
    Never enough power to think about supplying to the grid.

  67. Richdo says:

    meh.
    I’m thinking of installing a coal fired steam electrical generator for my house. I’m told it’s a promising technology.
    http://reliablesteam.com/RSE/RSEengines.html

  68. Ack says:

    We will need new entitlements, cant expect the poor to pay for these upgrades to their houses

  69. Gail Combs says:

    Dennis Cox says:
    December 13, 2012 at 11:16 am
    ….. Here’s one of two solar racks on the property.
    ______________________________________
    Yes but what was your cost? (Ball park)

  70. RACookPE1978 says:

    The ONLY reason these people think that “underground power lines” can work is because New York City used $2.00/day untrained “raw-meat” immigrant labor without OSHA and EPA and pay and retirement conditions and today’s sick leave and today’s restrictions on work permits to tear up Manhattan’s streets for years in the very early years between 1895 and 1903. New York’s unique congestion but simplicity of evenly gridded evenly-sized North-South and East West streets and a much-simplified single all-powerful (though all-corrupt) government “permitted” the disruption to be tolerated as telephone and power cables were buried after the massive snow storms in winter 1888. (Power came to NYC in 1882 with Edison’s first Pearl Street power plant. The controversy (and expense and disruption of burying cables) began soon after, and continued even for several years after the 1888 blizzard, but that was the tripping point as far as public opinion changed.)

    The following is copied from the Christian Science Monitor: Look at the WASTED costs required to replace today’s millions of miles of working power lines with less-reliable and harder-to-repair buried cables!


    Hurricane Sandy left more than 7.4 million homes and businesses without power and knocked out mass transit along a wide swath of the eastern United States from the Carolinas to the Canadian border.

    It will not be the first time – nor will it be the last time – a major storm knocks out power for millions. High winds, broken tree limbs, and lightning strikes are a familiar foe to exposed, elevated cables.

    The question arises: Why aren’t power lines underground?

    Some already are. San Diego has been putting utility cables underground since 1970 and hopes to bury all residential-area lines within the next half century. In 2003, the California Public Utilities Commission approved an “undergrounding” surcharge on San Diego residents’ electricity bills. The city buries 20-25 miles of utility lines each year at an annual price tag of $54 million, according to its Utilities Undergrounding Program website.

    After last October’s surprise snowstorm left 3 million in the dark across the Northeast, Boston Gov. Deval Patrick entertained the idea of buried power lines during a press conference.

    “I love the idea,” the governor said. “Apparently, though, that is a $1 trillion project across the commonwealth. And that cost and how to pay for it, no one has answered yet.”

    Therein lies the challenge. While it may seem logical to bury utility cables to avoid the inconveniences and dangers of downed power cables, the upfront costs of transplanting is steep.

    Building new underground transmission lines is five to 10 times more expensive than putting up overhead transmission lines, according to 2009 study by the Electric Edison Institute, an association of shareholder-owned electric companies. So the costs of converting from an overhead to an underground system range anywhere from $80,000 per mile in a rural area to $2.1 million per mile in a city.

    Even when the cables go underground, they aren’t necessarily 100 percent protected from nature’s wrath.

    In Manhattan, there are about 21,000 miles of underground cables. Nevertheless, most of downtown Manhattan was darkened Monday by power outages because of hurricane Sandy’s record storm surge of nearly 14 feet, which caused widespread flooding. Consolidated Edison, the utility serving the area, had warned on Sunday that it could cut power to customers in Lower Manhattan to help protect the cables from flooding.

    In all, more than 650,000 customers in New York City and Westchester County lost electrical power due to the hurricane, three times the number affected by hurricane Irene in 2011, the utility said.

    “This is the largest storm-related outage in our history,” John Miksad, Con Edison’s senior vice president for electric operations, said in a statement Tuesday.

    Even if the frequency of outages is diminished with underground cables, some studies show that the duration is not. A comparison by North Carolina’s investor-owned electric utilities found that the average duration of an underground outage was 58 percent longer than an outage in overhead cables.

    Despite the drawbacks, many still call for subterranean utility cables. Underground cables are less vulnerable to natural disasters and pose a lesser threat to wildlife and low-flying aircraft, advocates say.

    Now. consider the trillion-dollar estimate in the Christian Science Monitor story for the very small (geographically) state of Massachusetts. There are 10,800 MILES of power lines (most now with digital cable service lines plus telephone lines on the same poles!) in my single county ALONE! So, to bury 32,400 equivilent MILES of wires and cables and fibre-optic lines – throwing away all of the old wires – (because they cannot be used underground, nor serviced/replaced/repaired underground, nor hooked up to new/changes customers) and adding hundreds of of thousands of NEW underground access manways) is going to do what?

    Improve what?

  71. RACookPE1978 says:

    Just added up last year’s entire electric bill: We are in north GA (US) just above 1200 foot elevation in the Appalachian foothills. County population is 700,000 people. Heat and hot water are natural gas, power is electrical. Oven is electric, as is clothes dryer. Biggest electric load in the summer is the air conditioner. Winter electric bills are just under $100.00 per month. Summer bills, May through Sept, are obviously higher. March and April, September through Nov, are the lowest of the combined gas + electric bills.

    Total power used last year was 10050 kilowatt-hours
    Total cost for electricity for the entire year was $1215.84
    Actual average rate for the year was $0.12 per kilowatt-hour.

    The cost to install a (with a two day reserve) electric stand-alone solar system was (in 1998 dollars) $22,000 dollars.

    How many of your neighbors (Heck, how many grandmothers in the fifth floor apartments in New Jersey or out-of-Manhattan New York City) do you trust to install 12 or 18 50 pound lead-acid batteries in their basements or attics or back-bedrooms, compete with hydrogen monitors, battery re-chargers, battery monitors to detect/prevent hydrogen explosions after charging all night, H2 fans and vents, DC-to-AC converters, and line trip sensors ……

    Hook any of those up wring and you get fires, flames, arc and sparks, ….

  72. Silver Ralph says:

    Anthony: OK let’s assume the local big box store/warehouse has live solar power, with the power pole infrastructure wrecked, how do you propose to get that power out to the neighborhood? – Anthony
    ____________________________________

    In Europe, we have not had wires on poles for more than 80 years, except in some really rural locations. I still cannot understand why ‘rich’ America, which suffers from many hurricane/tornado events, still insists on putting electrical wires on poles. Its so, well, 19th century.

    .

  73. Curt says:

    As someone who designs industrial electrical inverters for a living (and who spent the morning reviewing the safety and robustness of one new design to the sudden removal and application of grid power), I will add my voice to those who say there is no engineering reason why a home solar power system could not safely and reliably be disconnected from the grid when the grid goes down and yet still be able to supply electrical power to the house. (Utility rules are a different matter…)

    The designs that Anthony describes automatically disconnect the solar panels from the DC side of the inverter when the grid goes down – that is, they disconnect at the input to the inverter. It is also possible to automatically disconnect the AC side of the inverter from the grid – that is, to disconnect the output of the inverter from the grid, but leave it connected to the house’s internal wiring. (AC disconnects are actually more reliable than DC disconnects because they can pull out as the current passes through zero.)

    The real issue is that a typical solar system designed to work when tied to the grid will not be able to handle the inevitable, and often unpredictable, swings in both supply and load that will occur. Significant storage capability is required, even to handle something simple like a passing cloud. This vastly increases the cost of what is already a fundamentally uneconomic system, and very few people would be willing to pay for it.

  74. mib8 says:

    This is the first I’ve seen the term “grid-tied”, so maybe it has implications different from what I’d expect.

    I’m not an expert, but know a little about it. My father was a power plant operator and I used to sneak his manuals and read them. A few decades back I took a serious look at solar, decided the cost and efficiency just weren’t practical or likely to be for a long time. Then I worked for a couple years for the state Publick Disservice Kommissariat as I like to call it (as a software developer and maintainer, not an electrician, but you pick things up). More recently, I’ve been reading some residential electrician books.

    Co-generation systems have been around since at least the late 1970s. There were some problems with early switch-over systems, for changing between drawing power from the local electricity monopoly to feeding power to the local monopoly, which created the kinds of problems Anthony mentioned. Ditto on home emergency generator systems; the simplest have a switch that cuts off from the monopoly, then cuts on the lines to the emergency generator. But newer automatic and manual switch-over systems, under the NEC standards, have, the best I can tell, worked around those problems, though they do seem very expensive from my POV. They do not throw power onto the local monopoly’s lines when an outage is detected. (The other day on a walk I noticed, outside their offices, they have a set of emergency generators and diesel fuel tanks and switching systems, all in a neat package amidst the landscaping. In Chicagoland, they have big, ugly, diesel generators at some of the sub-stations.)

    But then I haven’t read any recent material on them for solar panel systems. All of the old solar generating systems books assumed you had to have a bank of batteries.

    How do store-bought UPS (uninterruptible power supply) systems handle the switch-over from line current to the battery?

    I’m sure it could be done. Oh, and storm damage does not damage everything, nor is what is damaged equally damaged. In the middle of a hurricane area, you can see a neighborhood with some houses leveled and others hardly touched. Of course, tornadoes are infamous for this. So, yes, it might tear some solar panels from the roof, or not. Power lines go down here fairly often. (Not like the old days, when we used to pre-emptively shut down the super-computers every time a thunder-storm was approaching to avoid disk crashes, but, in any one part of town, once or twice a year. And they still use manually re-set circuit breakers next to each transformer so that a crew has to cruise around searching each time one is kicked… another 2-3 outages per year; no GIS-linked outage triangulation systems and automatic re-setting breakers here.) The monopoly blames the squirrels.

  75. pr says:

    According to the article “The Last Days of Mary Kennedy” on the Daily Beast, an article clearly endorsed by the Kennedy family, the green house RFK Jr and his wife Mary built was very expensive to maintain and the solar panels were falling apart, just a few years after it was built (of course, the article alludes to the failings of the project as being Mary’s). If this is in fact his personal experience, why push others to take on this unnecessary expense, too. From the article:

    “Though their marriage seemed to be ending, Bobby wanted to give his wife a purpose and their relationship a final chance, so he agreed to let her redo the house. Like so many other things in Mary’s life, it was on the surface a splendid achievement, so much so that a book was written on the Kennedys’ green house. But it had cost double the original estimate, and now, half a dozen years after starting the project, the solar panels were already falling apart, and it was costing $40,000 a month to maintain the house and staff.”

  76. RACookPE1978 says:

    Well, you’re welcome to your opinion about 19th century values, but if you’d welcome 19th century pay rates and 19th century death rates-per-km-of-buried-power-lines, and 19th century level of quality for electric power, and 19th century level of expenses ….. I’d be glad to provide 19th century buried lines.

    If YOU were the one paying.

    But 28% of US customers are served by (rural) electric membership cooperatives. They have 50 MILLION miles of wires and cables that need to be thrown away and replaced (for no gain) with buried cables. You going to pay for that?

    Roughly 15% of US customers live in highly urban downtowns where buried cables already exist. These highly restricted downtown areas correspond to the “Europe” you live in.

    So, 28% are served by rural lines already existing.
    15% are served by urban lines not needing replacement, but very, very vulnerable to flooding,earthquakes, fires, access, etc.
    What are you going to do to pay for the other 60% where buried lines cost too much and there is STILL no benefit to throwing away pole-and-insulator systems? That still work.

  77. Steve from Rockwood says:

    RockyRoad says:
    December 13, 2012 at 11:23 am
    They could always bury the copper …
    ——————————————————–
    It boils down to cost. One one side is the $30-$50 billion clean-up bill that happens every 25-50 years. On the other hand is the billions of dollars required to bury the copper. Where I used to live the locals insisted that every new subdivision have buried hyrdo lines. So going forward there would be less and less infrastructure affected. Of course the transmission lines (above ground) would go down so the underground delivery lines wouldn’t help. But we were never without power for more than a full day.

  78. Larry Ledwick (hotrod) says:

    In Europe, we have not had wires on poles for more than 80 years, except in some really rural locations. I still cannot understand why ‘rich’ America, which suffers from many hurricane/tornado events, still insists on putting electrical wires on poles. Its so, well, 19th century.

    Have you ever considered the cost of fixing something that is not broken, like burying a few million miles of power lines that get the job done just fine?

    We do have underground utilities in some locations, New York started putting some lines under ground following a major blizzard over 100 years ago, and many newer subdivisions are going to under ground utilities but lines on poles are still far cheaper than burying the power lines.

    When you factor in that we have states several times larger than European countries, and you understand the scale of the suggestion you are making it would be a ridiculous waste of money to retro fit existing power to underground lines especially in built up areas where they would have to work their way around 100+ years of underground construction like water sewer and natural gas lines. In many areas of the country like the Mountain states it is not a trivial task to dig in utilities due to shallow soils over rock. It is far faster to string lines by drilling holes and dropping poles. They can extend lines at a rate unapproachable for buried lines.

    The Denver metro complex covers thousands of square miles and has a population of only 2,599,504 as of 2011. The urban corridor along the front range extends over 100 miles in length to near Cheyenne Wyoming and another 80+ miles south to Colorado springs and has a total population of about 4.6 million people. The corridor is 30-40 miles wide near Denver, narrowing to around 20 miles wide in most other locations. The average population density is around 1700/sq mile over most of that corridor, with a few areas getting up to 3700 – 8400 / sq mile in the core city areas. London for example has approximately 2x the population density and it has an area of just over 600 square miles compared the Denver metro area of near 8,400 square miles.

    Europe had the “advantage” of being bombed to rubble in many areas nearly 70 years ago, so they could start from scratch on the rebuild and bury power lines during the reconstruction and subsequent growth that followed the war.

    Larry

  79. KevinK says:

    “vulnerable system of copper wires and wooden poles.”

    Well I suppose we could use super high strength steel for the wires. That way when the wire is stressed it won’t break right away, it will take a while before it lets loose and takes a few arms or heads with it. Oh and those awful wooden poles, must replace all of those right away with fiberglass, that way when you need a new pole you can just order one from the factory and wait 6 weeks.

    “Electricity-producing photovoltaic panels installed on houses, on the roofs of warehouses and big box stores and over parking lots can be wired so that they deliver power when the grid fails.”
    Sure, it will be much easier to fix a whole grid of wires from hundreds of sources out to hundreds of destinations. Rather that fixing a grid from few sources to hundreds of destinations. Ought to be back up and running in 30 days rather than 10. And transfer switches all over the place along with fusing to protect everything. Should be fun when all of the out of spec inverters try to feed the grid with 58 Hertz instead of 60. Then you get to fix half of it twice……. Boy I should go into electrical power engineering, looks like about two centuries of steady work at least.

    Do you get the feeling that these dupes don’t even plug the cords from their appliances into the wall outlet themselves ?

    Cheers, Kevin.

  80. Gail Combs says:

    Real median household income in the United States in 2011 was $50,054. When you figure in taxes the take home is ~ $3,600. Subtract about ~ $350/mo for a car loan, average student loan ~ $870 a month, the average credit card debt of $16,000 translates to at least another $400 and if you are talking the average mortgage (Northeast) of $225,000.00 with payments of $1780.00 that is $3400 a month in fixed payments. (Housing costs various all over the place from $163,600 in the south, to $250,000 in the Northeast where Sandy hit. )

    Or you can look at it another way

    The average monthly cost of living (excluding mortgage and rent) for people in U.S. is $3195. Households in U.S. spend an average of $552 on Food & Drink, $463 on Getting Around, $535 on House & Home, $736 on Shopping, $680 on Health & Family, and $229 on Travel & Leisure per month.
    http://www.bundle.com/spending/data/mortgage-23/

    Any way you slice it the average person does not have the $$$$ to spend on solar or wind. Otherwise we would not be up to our ears in credit card debt. U.S. banks charged off a record $83.3 billion in credit-card losses last year.

    According to Sun Run Depending on the location and design of your system, the typical home installation ranges from 3 to 7 kilowatts and costs between $18,000 to $40,000 to purchase. That is a major purchase equivalent to buying a car which for most of us is a necessity. Solar or wind is nice to dream about but most homeowners are just trying to make sure they can hang onto the house. Also with the drop in housing values who is going to dump another $20,000 – $40,000 into a property with a mortgage that is already higher than the value of the home?

    I think what you are going to see is a decline in the market as those interested and able to buy have already invested while there were subsidies. Given the U.S., subsidies are disappearing I think the market is maturing and the demand will continue to drop off unless it is artificially propped up by the US government.

    With the Fiscal Cliff looming, and US solar manufactures unable to compete with China and going bankrupt, Obama & Co. are going to have to do some fast talking.

  81. Massimo PORZIO says:

    The real problem of the solar panels attached to the power grid is their stochastic behavior. The biggest issue of the power grid is to keep the voltage constant independently by the loads/sources changes. Solar panels are tolerated until they produce so little energy that the gird is unaffected by their production. When the solar panels will be able to change the grid power significantly, the grid owner should be able to quickly reduce or increase the conventional power generation to counteract the changes induced by the possible sudden (and localized) solar flux changes induced by eventual atmospheric changes (read changes in clouds patterns).
    Here in Italy, the grid owner Terna asked and obtained from the government a new law in July, The new law imposes to the solar panels owner with a production potential power greater than 6kW to install automatic circuit breakers which shut down in less than 500ms the solar panels in case that the power production exceeds the +/- 15% voltage margin (note the plus sign too). That law exposes the truth about the solar panel energy production: no power is really shared to the grid, it’s just tolerated.
    The owner of the solar panels reduce his/her energy bill of course, no doubt about that, but the community is paying for his/her energy (the one “sold” to the grid, but the one self used too). That’s because the grid must be supplied to warrant the continuity in case of sudden changes in solar irradiation, which is unpredictable. This means that no CO2 is reduced by that “green energy” because the power stations never reduced their production till today, and since it’s close the day when they have to deal with the problem of the quick power modulation, they asked to automatically switch off the stochastic producers themselves. They don’t want the solar energy on their grid because they can’t do nothing with it, they currently just dissipate the shared “green energy” heating the lines.
    From the stochastic perspective, the wind farms energy is just a little better than the solar, but not so much.

  82. Obviously an attempt to gain attention. It is PR move and given the way that people, including the MSM treat press releases as somehow Gospel who knows the result.

  83. Justthinkin says:

    “RockyRoad says:
    December 13, 2012 at 11:23 am
    They could always bury the copper and use steel poles instead of wood where necessary, but that would drive electricity rates up and beyond acceptable levels.”

    And taxpayer subsidised PV/wind doesn’t?? Suggest you ask any honest EU power payee how that’s working for them.

  84. eric1skeptic says:

    ferocious20022002 (December 13, 2012 at 11:32 am) said: “On the minus side, I have to thank you all for helping to pay for it. Various tax credits, federal, state, and from the power company paid for $13000 of the cost. Along with Solar Renewable Energy Credits, mandated in PA for generation companies, which bring in around $1000 a year our return on investment has been about 6%. One of those uneconomic fovernment mandates that have raised the cost of electricty. Even without the subsidies I would have gone ahead with it anyway. The ROI would have been about 2%, but at the time, and for the forseeable future that looks pretty good.”

    Thanks for mentioning the credits ferocious. But there’s huge subsidy you didn’t mention. You get full retail price for the power you generate (i.e. it slow the meter at the retail price). Yet your power is off-peak and unreliable. Wholesale power is about 4 cents and is reliable and delivered at all times. Your power is costing all of us 13 cents or more.

  85. John M. Chenosky, PE says:

    It is amazing what government involvement will create. As Alan Greenspan said in a moment of clarity.. ” government is inflation”.
    We chose to live in the country and when I built our current house, I purchased a full house generator, for temporary construction power and as standby emergency unit. The generator is a used industrial ONAN, propane fueled, 30 KW, 208/120/3/60, 100A.
    At the time, I998, I spent $ 4500 for this 6 cylinder,1953 flat-head Ford beast with less than 3000 hrs.
    It now sits in a remote, dedicated, heated, insulated shed 75 feet from the house along side the buried 1000 gallon propane tank. It has been a workhorse. The last time it provided Sandy power for 48 hours and you had to really concentrate to hear it running. It is isolated from the utility with a Manual Transfer Switch connected to the main panel that feeds two auxiliary panels.
    As a retired Professional Engineer I looked into Wind and Solar and then looked away. Having worked in the battery business in another lifetime, I knew the back-up technology was a decade away and in my opinion, it is still a decade or more away.
    In my research I believe the solution is miniature nuclear generators, as manufacturered by Mitsubishi, NuScale and others. These self-contained Thorium fueled units can be isolated from the Grid and can power small communities, neighborhoods and ultimately 4 acre properties like ours. They are safe, hermetically sealed and virtually maintenance free. Read the literature. I hope I’m alive to see it implemented.
    PS – I have three phase power to my pole barn wood shop. If I can figure out how I can buy and then hide a new 5HP table saw purchase from my wife, I’ll be able to use the generator.

  86. Steve from Rockwood says:

    Silver Ralph says:
    December 13, 2012 at 3:29 pm
    Anthony: OK let’s assume the local big box store/warehouse has live solar power, with the power pole infrastructure wrecked, how do you propose to get that power out to the neighborhood? – Anthony
    ____________________________________

    In Europe, we have not had wires on poles for more than 80 years, except in some really rural locations. I still cannot understand why ‘rich’ America, which suffers from many hurricane/tornado events, still insists on putting electrical wires on poles. Its so, well, 19th century.
    —————————————————————
    This is where I like to tell the story of my Dutch friends who flew to Canada and decided to drive from Toronto to Vancouver, then up to Alaska and possibly finish their vacation in Seattle before driving back to Toronto for a return trip home to Holland. Of course it would be no problem because they had booked 2 weeks off.

  87. _Jim says:

    Silver Ralph says December 13, 2012 at 3:29 pm

    In Europe, we have not had wires on poles for more than 80 years, except in some really rural locations. I still cannot understand why ‘rich’ America, which suffers from many hurricane/tornado events, still insists on putting electrical wires on poles. Its so, well, 19th century.

    Ralph, Ralph, Ralph, I’M WILLING TO BET *I* (or even we collectively in the USA) have more nines (“9s”) in my (our) electric service ‘up-time’ than you do (referring to 99.99% ‘availability’ or up-time vs 99.999%) in your ‘European’ system …

    We also live in cities where the distance across any given town is measured in double-digit miles versus single-digit kilometers too.

    .

  88. _Jim says:

    KevinK says December 13, 2012 at 4:23 pm
    “vulnerable system of copper wires and wooden poles.”

    Well I suppose we could use super high strength steel for the wires. …

    sur-PRISE!

    I don’t know anywhere where distribution system lines are going as COPPER wire when Aluminum has COST and WEIGHT benefits when properly engineered …

    I reckon not very many ppl here have considered all this from a materials and suitability perspective yet. Kinda falls right in with Kennedy and Crane practicing electrical engineering without knowing the FIRST thing about the field either …

    .

  89. tango says:

    should be no news to anybody we all know that most of them are brain dead

  90. @Steve from Rockwood

    Great analogy! I’ve driven across the USA several times, when I was a young man. Damn! That’s one looooong frackin’ drive! No way I’d do it again, unless I had an RV, unlimited funds, and no deadline whatsoever.

  91. DesertYote says:

    I would not trust a word out of David Cranes mouth.

    It might come as a shock to some, but the average Corporate Exec. and Board member is a lefty. The trend started in the mid 80’s.

    As a general rule:
    Wealth manipulator (Real estate, Banking, Insurance, etc) -> Lefty Socialist
    Wealth creation ( mining, farming, manufacturing, construction, etc) -> Conservative

    Corporations are controlled by their boards. Their Board Members are selected from the investment community. The investment community is made up of wealth manipulators.

    Nota Bene, I did not write right-wing conservative because Right wing is not the antithesis of Left wing. Both are just versions of socialism that topological are barley distinguishable.

  92. john says:

    John M. Chenosky, PE says:

    Right on. I started out in the engineering trade 30 years ago and for the most part of 15 years worked in the wind, solar and hydro sector. I have built quite a few remote (off-grid) systems and done quite a few utility inter-tied ones as well prior to 2000, as well as large scale wind. After my stint there, I worked a a power lineman and was Fire Chief for a volunteer fire department. I know transmission and distribution quite well and cannot in good conscience support the wind or solar industry.

    I am very aware of why wind and solar have failed in too many instances and will continue doing so. High cost and poor siting/system design has haunted the industry and it will continue to fail. I laugh at the lack of intelligence of Mr. Kennedy et.al. as they know nothing, literally of what they say. Safety is a rather big concern especially with battery based systems. Another concern besides accidentally back feeding the grid during outages are solar panel covered roofs. It’s a hazard to fire fighters and makes venting a structure fire even more difficult. I could go on and I will as my current efforts are exposing the frauds and waste associated with the industry.

    john from the Daily Bail

  93. Philanthropist says:

    A thorium reactor in every neighbourhood seems like a better idea than the grid thing…

  94. _Jim says:

    DesertYote says December 13, 2012 at 6:25 pm

    Nota Bene, I did not write right-wing conservative because Right wing is not the antithesis of Left wing. Both are just versions of socialism that topological are barley distinguishable.

    If I may ask, DesertYote, what publications/websites do you read?

    Does the list include PowerLineblog.com, Instapundait.com or Althouse by any chance? Would you consider those RW Conservative sites or simply ‘conservative’ sites in your estimation?

    I’m just trying to figure this out, i need a little ‘vectoring thrust’ as guidance to understand your perspective.

    .

  95. _Jim says:

    Philanthropist says December 13, 2012 at 6:41 pm

    A thorium reactor in every neighbourhood seems like a better idea than the grid thing…

    Hmmm, gee, wound’t that work to be a …. –wait for it– … a ‘grid’ thing too?

    I think WAY TOO MANY people lack the understanding/don’t posses the technical education to recognize the “spoke and wheel topology” of the local distribution network versus the “X-Y interlaced grid architecture” of the transmission (and generation!) side of the system.

    See, on the one side we have generating plants and these are connected to substations via ‘transmission lines’. The substations in turn are interconnected via more transmission lines and also interconnected to general ‘switching yards’ … this all has the effect of creating “multiple paths” nowadays commonly referred to as a ‘grid’ (patterned after the idea of a 2-dimensional X-Y grid don’t ya know!) These multiple paths allow a degree of ‘failures’ (or out of service for repair, etc) to occur AND not completely disrupt service to customers, the multiple connections to/and from substations also allow various generating stations to be out-of-service (OOS’d) without disrupting service .. were ‘gridding’ not practiced at the generation-transmission level each city, each arbitrary load ‘district’ would see MANY, MANY more ‘outages’ since there would be no immediate redundancy in generation or transmission.

    So, let me ask a couple of questions:

    (1) Do you have two or more fuses for each circuit in your home (this how the transmission and generation side in the actual ‘grid’ work) with various circuits cross-connected at various miscellaneous and flexible (as need arises) points?

    (2) Or do you have exactly ONE fuse in line to each circuit (excluding the main fuse of course) as the spokes in a wheel extend out from the (a) inner hub to the (b) outer edge of the wheel?

    .

  96. Robert of Ottawa says:

    Electricity-producing photovoltaic panels installed on houses, on the roofs of warehouses and big box stores and over parking lots can be wired so that they deliver power when the grid fails.
    … at night?

  97. _Jim says:

    mib8 says December 13, 2012 at 3:47 pm

    How do store-bought UPS (uninterruptible power supply) systems handle the switch-over from line current to the battery?

    The cheaper units handle it quite crudely; think mechanical relay (one can literally hear the relay click!)

    Higher priced units perform switch-over with solid-state device with time frames measured down to a cycle while, the high-end units do AC-DC-AC conversion and nary a cycle is missed …

    I had complications with a low-end APC (relay switchover) just months back; the rendered freq was measuring in the 47 Hz range and the attached PC would see the power ‘glitch’ just after the APC was switched on (this series of APC UPSs does a brief power-from-battery test every time its powered up, and at this time in its life this time there was an issue even with a fresh battery …)

    .

  98. Stan says:

    What happens when you connect your 1500 watt solar panel to the 15 megawatt load of the dead grid?
    Not much…
    It would almost be like a dead short!

    Or wait a minute!
    Maybe we can power a huge power grid with a couple of little solar panels!
    …In liberal lala land….

  99. I think this is sorta-kinda relevant—I used to manage a fairly large computer center (back when a computer occupied most of two floors).

    We had a 250 KVA UPS and one night (for reasons that it turns out did not make sense at the time and that I have forgotten) I over-rode the system logic (it knew better) and tried to power all of down-town San Jose with our batteries.

    I still have nightmares about the possibility that I might have killed or injured somebody.

  100. Many houses here in the North East of England have solar panels on their roofs. The logic of them here escapes me, at this time of the year the sun rises at about 08:30 and sets at 15:35 and at noon is only 12 degrees above the horizon. The current outdoor temperature is -3 Celsius, so the current demand for power is at its highest. In summer when we don’t need the power (very few buildings are air-conditioned) the things are kicking out loads of power. There have been enormous government subsidies for these things, paid for by higher electricity bills for he rest of us. No mention though of : “It’s worse than we thought”.

  101. johanna says:

    This issue is not whether it is possible, or even sensible. The issue is the cost vs the benefit – a subject on which solar proponents are without a leg to stand on without lavish subsidies from everyone else.

  102. Latimer Alder says:

    I am second to nobody in my loathing for subsidised solar panels.

    But the criticism above seems to be a bit overblown. Would it not be possible to come up with an intelligent switch that senses that the power grid has gone away and just routes the current internally, not externally.

    I’m not an electrical engineer, but this doesn’t sound like rocket science to me.

  103. Kev-in-Uk says:

    andrewmharding says:
    December 13, 2012 at 11:02 pm

    I am in the NE of Uk too – and you are quite correct, the solar generation capacity in the UK has been far overblown and most folk have only had the panels installed to get paid exhorbitant FIT rates. In other words, these people are simply ripping off the normal consumers (via a government approved system!). I genuinely hope that the panels are less efficient and fail earlier than advertised and will be amused as they fail watch as they fail to recoup their greed inspired investment. Put it another way, I wonder how many of these folks are really green, and would have still paid the installation fees if there were no subsidy? Not many, I’ll wager!

    The solar powered house I was at in Portugal had a battery system which only just about managed through the NH winter (i.e. stored pretty much as much as was used) and that was located some 10deg of latitude further south! I genuinely cannot see any benefit (other than the FIT !) from solar panels in the UK , and certainly not in the north!

  104. Jack Simmons says:

    I wonder if Kennedy has the home set up to run green. Or is he like Gore telling the rest of us what to do and doing the opposite?

  105. Andyj says:

    Kev-in-Uk says: “…….I genuinely hope that the panels are less efficient and fail earlier than advertised and will be amused as they fail watch as they fail to recoup their greed inspired investment…….”

    Anyone would think you have a dog in this fight. ;)
    I live in the UK and consider those who rented their roofs to be fools. However, I sincerely want UK Solar panels to be successful because it means those who are really paying for this, ( all of us ) are going to suffer less.

    For a house in Portugal with Solar panels to barely cover its electricity usage when houses in the UK do.. Now that’s an eye opener.

    Mono crystalline panels with CE approval can now be bought for as little as ~400GBP per KWH (max). Adding in accessories, taxes and fitting with an approval certificate It must be 4x that.

    Like the electric car it sounds expensive initially but consider this; The light in my living room had three 60W incandescent bulbs, (180W) for 15yr’s@~6hr/day. 10p/KWH = ~£550. Now my bulbs are 14W the effective cost is 10% of before. We are now ~15p/KWH so add half again. Energy costs are spiralling, the fuel wars are under way: Syria has 3 billion tonnes of shale oil and gas.

    Solar panels are one of the best no-brainer investments there is if you are love and own where you live and financially a creditor. What Anthony has done to his house ….and driving an electric car is applauded by me.

  106. richardscourtney says:

    Andyj:

    I read your post at December 14, 2012 at 5:01 am.

    It says you live in the UK and that you support solar panels, long-life light bulbs and electric cars.

    OK. Knowing you support those things, I have a proposition for you.

    Would you like to buy a bridge from me?
    It is across the Thames in a very desirable location near the Tower in London.

    Richard

  107. E.M.Smith says:

    @Jim:

    The use of “left” and “right” are broken terminology. It is functionally meaningless and has been turned into “politically correct” vs “evil people” in the MSM here. But even looking at it historically, they are broken terms.

    In the beginning (French Revolution) it was what side of their parliament you sat on. Kings and Bishops (central power authorites) on The Right, petty businessmen an rabble (‘proletariat’) on The Left. Over time, when socialism came along, they got assigned to The Left. Somewhere indistinct after that, they tossed Businessmen over to “The Right” (and generally the church got forgotten…). Along came the “Third Way Socialists” (aka “Progressives” of the time) and they started on The Left. But there was this little “dust up” they had with the UK / USA and Russia. When Stalin announced that Der Fuhrer (and his National Socialists) were not Left enough to be good communists and pronounced them ‘Right wing'; as communists were for One International Socialism, and those guys wanted individual National Socialisms… (That, BTW, is how Der Fehrer and Mussolini ended up as “Right Wing”… they and their Progressive National Socialism are a smidgen to the right of ‘as far left as you can get’ in Communism…)

    So how “sane” it is to use “right” and “left” when conservative busnessmen were on both sides at different times, and when Socialists, hard core Central Planning labor union loving public health care for all and origin of the Green Movement national Socialists were fobbed off as ‘right wing’ when they are kissing cousins of the Communist flavor of Socialism? (The only thing substantial about which they do not agree is “national” vs “international”… Stalin wanted to run the whole world..)

    The correct axis is to use “Central Planning” as your metric vs “Liberty and decentralized choice”.

    On that scale, the Evil Bastard King is on the same side as Der Fuhrer and Herr Commissar and the Tzar and Dear Leader and The Peoples Premier, and the EU Commissioner (or whatever they are called). On the other side is the free people with free markets, choice, and liberty. Decision making NOT centralized in The Federal Control Machine, but distributed to individual people, cities, counties, companies, and occasionally States. Self Organizing Systems.

    That is simply not captured in the Left vs Right broken stereotypes used as cuss words.

    Please don’t use this thread to start a “does so” / “did not” or “Is so” / “Is not” food fight over this. It’s been well researched and anyone who knows their history can see it. If you wish to complain that it doesn’t match a particular current bias, please read the links below first, and then take the discussion there if you feel compelled to plough ground already pulverized:

    https://chiefio.wordpress.com/2011/01/20/nationalist-socialists/
    http://chiefio.wordpress.com/2012/03/05/isms-ocracies-and-ologie/
    http://chiefio.wordpress.com/2011/03/25/some-quotes-on-socialism-and-fascism/
    http://chiefio.wordpress.com/2011/01/15/liberal-fascism/
    http://chiefio.wordpress.com/2011/03/15/fascist-doctrine/

    Oh, and the word “Liberal” has been corrupted by the American Progressive Movement when they ran screaming from their endorsement of the Third Way National Socialisms of Europe that ended up in the W.W.II disaster. (Mussolini was beloved of American Progressives and Hollywood prior to that … even does a cameo in a Hollywood movie of the era.) As “Progressive” had become tarnished, they adopted “Liberal” (much to the chagrin of the actual traditional Enlightenment Liberals of the day… what we would call Libertarian now, or as close as we can get). That, BTW, is why the “Liberal” party in Commonwealth countries tends to be the Conservative party while in the USA it’s the “Socialism Lite” party (until recently when it became flat out Socialist. I’m not using that as a pejorative, BTW, but as a technical economic descriptor. I’m an economist who had to study socialism to get my degree… We are “Lange Type Socialism” at this point.)

    http://chiefio.wordpress.com/2011/01/19/i-am-a-liberal/

    kind of lays that out. We have American Social Liberals and Europe / Australia New Zealand have Classical Liberals.

    Oddly, now that “Liberal” has become tarnished in America, we had Madam Clinton trying to distance herself from it by saying “I am not a Liberal, I’m a Progressive!”… Apparently trusting that no one remembered history… And then Billy Clinton said his polices were not Liberal, they were “Third Way”… (both on tape, btw). Just Amazing… (Mussolini popularized the “Third Way”, FWIW, as a “third way to Socialism”… )

    Again, please don’t hash that out here. It’s very Off Topic. Head over to my place as it is very much something we discuss there.

    Back On Topic:

    I once met a local State Senator who was a Kennedy Wannabe and hung out with them…. They came out to a morning balloon meet to see a Hot Air Balloon and take rides. So I got to see some of the Kennedy Clan up close along with this guy….

    Most intelligent thing they said was, er, not that bright. We’ve already called it a “Hot Air Balloon” about a dozen times. We’ve just gotten it inflated and poured enough fire into it (about 8 foot tall flame thrower sized fire…) to be upright on the ground. The best and smartest thing they could come up with? “So, it uses hot air does it?”

    Never saw so much posturing and preening with so little ‘inside the skull’ in one spot, before or since. IMHO, JFK was their shinning moment…

    On Grid Stuff:

    IMHO the best way to do it is have a battery bank and inverter to power the house. A nice fat plug plugs a charger into the wall power (240 VAC 3 phase in the garage). Solar panels charge the batteries too. (Charge controller, smart one, mixing the two chargers). Now you don’t have a ‘grid feedback’ to worry about. Just unplug if anything bad happens. Leave it plugged in when solar is below needs.

  108. Ric Werme says:

    > In a nutshell, when the power poles go down, the inverters lose connectivity to the grid, sense this automatically, and shut themselves off.

    Suppose power to a neighborhood is cut off. Suppose several buildings in the neighborhood have Solar PV systems and (at the moment) are producing all the power the neighborhood needs. How do the inverters realize that the grid power is lost? Change in power factor? Drift in the line frequency? The 99+% chance that even if load equals demand at the moment it won’t match in a few seconds?

    What works great for a single installation or with a sizable difference between supply and demand sounds fraught with risk when scaled up.

    Also – given that issue being addressed is survival through storms, and storms usually bring clouds, then there’s no chance that the neighborhood will be self powered when the grid connection fails. Then there’s no chance to repower the neighborhood without a lot of interesting new technology that connects the smarts of all the PV systems.

  109. Kev-in-Uk says:

    Andyj says:
    December 14, 2012 at 5:01 am
    No – no dog in the fight as such. But I know of several folk who rushed to get their panels before the FIT change deadline, etc – even borrowing the money to do it, on the basis of the ridiculous FIT being ‘guaranteed’. They were not being green, just greedy – thinking they were going to get something for nothing (a bit like the energy suppliers and their green investments!).

    Re the Portugal property, the system was a good several years old, and only small (panel array was only about 2m x 1 m); it was a 24V system with an inverter to the house mains (no mains electric at all) IIRC, and a genny for higher demand use (e.g. washing machines, etc). But in winter, the solar was only really enough to provide capacity or the house lights and a fridge through the day/night, with not much else – (so the addition of a wind genny was made). I’m fairly sure a bigger array and more modern panels would be more efficient! Looking at it, the difference in latitude was actually about 18deg too!

    I am actually in the process of acquiring a property to rebuild in Portugal and need to consider what to do re my energy needs (even though it does have mains electric at the moment) – so over the coming months I will be ‘reassessing’ the solar (and wind) cost/supply issues. Hopefully I will find that the modern gear is better than that I have used before!

  110. Ric Werme says:

    If you want something that doesn’t have the hassles and short life of lead-acid, NiCd, etc. batteries, people are cranking up production of Edison’s FeNi batteries. They look to be a great choice for home systems, a couple people I know in NH are using them.

    Very long life and low maintenance.

    http://ironedison.com/
    http://www.nickel-iron-battery.com/

  111. Silver Ralph says:

    _Jim says: December 13, 2012 at 5:52 pm
    Ralph, I’M WILLING TO BET – we collectively in the USA have more nines (“9s”) in my (our) electric service ‘up-time’ than you do (referring to 99.99% ‘availability’ or up-time vs 99.999%) in your ‘European’ system …
    __________________________________

    I have not suffered a power outage in the UK since 1978.

    I did get a cut in Belgium, but in mitigation apparently they were going through the trauma of having to generate their own electricity. Belgium was hooked into the German system and had had free electricity for 60 years, as WWII reperations. Bit of a bind having to actually pay for it yourself at last.

  112. Mike M says:

    REPLY:Point: “Electricity-producing photovoltaic panels installed on houses” seems to clearly imply homeowner to me. OK let’s assume the local big box store/warehouse has live solar power, with the power pole infrastructure wrecked, how do you propose to get that power out to the neighborhood? – Anthony

    Imply? Does the statement, “Heat producing boilers installed in houses.” imply that the homeowner does the work or simply point out where the equipment is being installed? Most heating supply vendors and equipment manufacturers won’t sell a boiler to someone without a plumbing license and the reason is liability so I wouldn’t expect a big box store to sell things like synchronizing power inverters directly to the public by any other means than a contracted installation service to minimize their liability exposure IMO.

    (But hey, 240 VAC is child’s play compared to what I’ve whacked with over the years. And ain’t it ‘funny’ how you never seem to forget the different ways you got zapped ‘good’?)

  113. In Wyoming, we often have very high winds. Our power lines are mostly above ground. The subdivision to the south of my home does have underground wiring. A few of the newer area do too. The change to underground sounds like a good idea, but cost and materials usage are very high. If one is going to demand the lights NEVER go out, perhaps we need a remedial lesson in real life? Also, I really don’t see solar panels hanging on in a hurricane. Even if you skipped the grid part and went with batteries and an inverter, the panels still have to stay on the house.

    Anthony–thank you for a very clear explanation and pictures of what grid-tied solar looks and works like.

  114. Darren Potter says:

    “Electricity-producing photovoltaic panels installed on houses, on the roofs of warehouses and big box stores and over parking lots can be wired so that they deliver power when the grid fails.”

    I read the line to mean, the solar panels could provide power directly to the building the solar panels are associated with. Not that the solar panels could provide power to the grid when the grid failed.
    The prior wording, “secure grid independence” is the key. Thus the line was meant to convey the use of Solar Panels as both a personal or private supplemental generator and as emergency generator. As such, the panels would be disconnected from the grid when grid power fails.
    The only reason to normally (non-emergency) still be tied into the grid is to handle the peaks, and reduce the power storage requirements.

  115. Darren Potter says:

    Latimer Alder says: “Would it not be possible to come up with an intelligent switch that senses that the power grid has gone away and just routes the current internally, not externally.”

    They are called Transfer Switches. When grid power fails, the connection to the grid is broken, then a connection to your emergency power source is made. Transfer switches are also known as a break before make switch (or contactor).

    There are also Smart Transfer Switches which will give priority to critical loads and rotate through non-critical loads to allow under-sized generators to pseudo do the job. Example: The switch is wired to keep your deep freeze, refrigerator, water well pump, plumbing heat-tape, and a few lights all powered. The switch would then cycle between central air and water heater. You might have the switched wired to run a stove or clothes dryer ‘one at a time’, and when those were not running the central air and water heater would get power ‘one at a time’.

  116. Stu Miller says:

    Gunga Din at11:29 am, Dec. 13
    In Washington State, it is illegal to operate a generator without an approved disconnect. Throwing the main breaker in your home does NOT reliably disconnect an emergency generator from the net. I suspect other states have the same type of law.

  117. Darren Potter says:

    Larry Sheldon says: “I used to manage a fairly large computer center (back when a computer occupied most of two floors). We had a 250 KVA UPS”

    A business baby UPS.

  118. beng says:

    Lead-acid batteries generate hydrogen. The more batteries, the more H2.

    Our power-plant emergency-lighting battery rack (250V DC) had to be in an enclosed building designed for the walls to move outward from an internal explosion and the roof collapse on & cover the rack.

  119. beng says:

    ****
    Silver Ralph says:
    December 13, 2012 at 3:29 pm

    In Europe, we have not had wires on poles for more than 80 years, except in some really rural locations. I still cannot understand why ‘rich’ America, which suffers from many hurricane/tornado events, still insists on putting electrical wires on poles. Its so, well, 19th century.
    ****

    Your “european” solution is inappropriate and unnecessarily expensive in most of the US other than urban areas. I pay $0.06 /KWH w/only rare outages. How ’bout you?

  120. LearDog says:

    Great point Anthony! And – you have the engineering and practical experience that give you the authority to provide informed comment.

    I suggest a short, concise letter to the WSJ editors to expose their flawed thinking. Something along the lines of
    “Sirs: even if the solar panels survive the windstorm AND the clouds part – there are regulations that prohibit transmission yadda yadda. It isn’t all that simple really”

    As a resident of Houston, my desired back-up in a natural gas-fied generator with an automatic cut-off. Next house.

  121. DesertYote says:

    _Jim says:
    December 13, 2012 at 7:17 pm
    ###

    I haven’t looked at any of those site in quite awhile, so I am not sure. But if you really would like me to give an example of the difference, I think I can.

    Bill O’Reilly tends to be a Right-Wing Socialist. Hannity tends to be more of a Conservative.

    Before Marxists highjacked the term, the antithesis of Socialism was liberalism ( which is different then libertinesm). Anyone who supports the idea that it is the role of government to drive society is a socialist, a breed that has existed since before history. (The idea that socialism is an economic theory is just a resent smoke screen to hide what the socialist true goal is.) The only term that is left to use in American English to describe those who oppose this is Conservative. The Right-winger is a Socialist created straw man that people are foolish enough to partially buy into, if they happen to object to the Lefty agenda. They don’t know any different. Any examination of the anatomy of the strawman will reveal that it is just a socialist coming from a different direction. BTW, I figured this stuff out on my own before there was an internet, before Rush Limbaugh, … before the Dark Times, so I am not picking it up from some blogger. Its the product of my own analysis and experiments.

  122. Steve Richards says:

    To those how are not electrically aware:

    If you do not ‘use’ the output of the panel/invertor it is not dumped into resistors etc, it is simply not used. You can have 240VAC or 120VAC produced all the time, if you do not switch on your heater, the take no current, it remains available till you need it (or darkness falls)

    Anti islanding is where the invert is continually checking whether the grid is up and running. If it finds the grid has failed, it switches off its output to the grid. It can do this checking in many ways,
    it can inject pulses of current into the grid for a microsecond, if current flows, the grid is there. It could also alter the inverter frequency for one cycle only and measure the current change, if it does, the grid is their fighting back, if the current does not change, the grid is down.

    All of the installations my friends have in the UK are grid tied, and the invert is wired in such a way that all of the AC wiring is on the electrical ‘suppliers’ side of the installation, any change to this is a prison sentence in the UK.

    Here is a snip from a US report:
    http://energy.sandia.gov/wp/wp-content/gallery/uploads/121395.pdf
    which details issues of connecting solar pv to the grid.

    It clearly states that a requirement exists disconnect from the grid when the grid fails.

    “The mandatory inverter disconnect from the grid requirement as part of IEEE Std. 1547 will
    likely be the source of grid instability as PV capacity grows. With higher penetrations of PV,
    utilities will value allowing PV and other inverter-based DG to ride through voltage sags or
    frequency disturbances. This is not possible with the stringent under/over voltage and under/over
    frequency tripping of PV inverters used today or with the present active anti-islanding
    requirements. These restrictive voltage or frequency trips can cause distributed PV to disconnect
    at a time when their continued operation would provide high value generation to the host utility.
    Thus, using stringent OV/UV and OF/UF settings to improve the detection of and response to
    line faults and loss of grid connectivity has limited the ability of PV to provide high value to the
    grid. Similarly, the active anti-islanding requirements are an impediment to DG based
    microgrids”

  123. jbird says:

    Most people here have missed the point entirely.

    It doesn’t matter if Kennedy is a moron and is totally clueless about the science and engineering behind solar energy. This guy has managed to score 1.4 Billion (THAT’S “BILLION” WITH A “B,” or ONE THOUSAND FOUR HUNDRED MILLION if you like) in taxpayer guaranteed loans for his solar energy company “BrightSource,” from the Obama administration. The taxpayer bailout was made after struggling BrightSource went 1.8 bilion in debt in 2010. (See http://www.dailymail.co.uk/news/article-2062638/JFKs-nephew-received-1-4bn-taxpayer-bailout-struggling-green-energy-firm.html). Yes Virginia there is a Santa Claus and he lives in the White House. Guess it pays to be well-heeled, well-connected, and to have the last name of “Kennedy.”

    It has been estimated that the BrightSource energy project currently being built in California will produce solar power that costs THREE to FOUR TIMES what power from conventional energy sources will cost. (See http://www.bizjournals.com/sanfrancisco/blog/2012/11/brightsource-responds-to-la-times.html) Who do you think will subsidize those increased energy costs? Yep. That’s right. It will be the good folks in California along with the rest of the US.

    As of November 9, 2012, BrightSource continued to struggle and was seeking to raise yet another 140 million dollars from investors. Keep in mind that no electricity has yet been produced from this boondoggle. I WOULD NOT BET AGAINST this company going belly up in another year or so after hoovering up millions in taxpayer dollars. The name “BrightSource” will be added to the long list of names of failed green energy companies that include such illustrious concerns as Solyindra. I suspect that Kennedy, and the others surrounding him will walk away from this mess after pocketing some nice salaries courtesy of the US taxpayer. That money will have come from rich and poor alike, both Democrats and Republicans. No doubt, some of it will be recycled back into the campaign of the next un-vetted, Chicago machine politician to be offered up to the electorate as a “hope and change” solution to our problems.

    WAKE UP PEOPLE! Of course Robert Kennedy is going to promote solar energy any chance he gets, whether he knows anything about it or not. Get a clue about what is happening. We are nothing but milk cows for a bunch of (frankly inferior) parasites. This is our country, and we need to take it back.

  124. greg says:

    I have been a solar panel installer. The power inverters that convert the dc power into useable ac power can not be fooled into turning on after the grid goes down. You would think that maybe by hooking up your gasoline generator to the inverter then maybe the inverter would be fooled that it is ok to turn on? Nope. Don’t believe me? Call the inverter company Fronious and tell them you want to produce power with the 40,000$ worth of solar panels you just installed so after a storm when there is no power you can still have power. You will have to buy the type of inverter/charge controller to charge up batteries, then use the voltage from the batteries to supply the inverter, which in turn supplies power for you house. Without the electrons from either the grid or batteries you will be sitting in the dark.

  125. Jeff Alberts says:

    Bill Taylor says:
    December 13, 2012 at 11:00 am

    our generator has a switch that unhooks the grid when it is running(except during its exercise run for 10 minutes weekly), when the grid power comes back the switch reverses the process and reconnects to the grid…..when we lose power it takes a minute before that switch acts.

    My 10kw Generac system is the same way. When power is lost, the generator kicks in within 10 seconds or so. When power comes back, the generator stays on for another minute or so before switching back to grid power, probably to prevent a quick on/off in an unstable power situation. No gasoline or diesel, though, runs on Propane. I have to top the bottle off once a year or so for the handful of annual outages.

  126. Larry in Texas says:

    Anthony, a very good job exposing another canard from the Kennedy clan and the solar fools. My dad had a huge knowledge of electricity and could do a lot of things around the house with electrical systems, but his knowledge didn’t rub off enough on me to enable me to do my own work. So I sure don’t mess with it in my house; I call the electrician when needed. Your post is an excellent way of telling people to NOT mess with electricity. Either get the right generator or find another way if you need a little power in your house when the grid goes down. Because you are either on the grid or you are off. There is no half-way on this one.

  127. Massimo PORZIO says:

    Steve Richards,
    “If you do not ‘use’ the output of the panel/invertor it is not dumped into resistors etc, it is simply not used. You can have 240VAC or 120VAC produced all the time, if you do not switch on your heater, the take no current, it remains available till you need it (or darkness falls)”
    Not really so, you must provide a device which converts the unused energy in something else (typically chemical work, in accumulator or capacitors) when your accumulator reaches its maximum capacity your inverter must have have an additional device (here in Italy we call it “braking resistors” , the term comes from the industrial control, where inverters are widely used to control motors) which keeps the voltage under the maximum allowed by the accumulator.
    So when you accumulators are full, the unused energy is finally dumped into resistors indeed.

  128. Massimo PORZIO says:

    @Steve Richards.

    Hops… I missed a thing
    Many solar panel system power-grid-coupled without any accumulation device haven’t braking resistor at all, because it’s the same solar panel string which works that way. That is, when the panel surface is irradiated but the inverter doesn’t supply the grid, the voltage across the panel rise directly polarizing the solar panel junction which dissipates, heating up itself.

  129. Ygor: This may work for some large scale applications (it still runs off the grid, it looks like, or may require a separate grid) but while some of the commentors said they run duel systems already and I use DC backup for power outages, I can attest to the fact that it is very difficult to get people to use DC. We use it at our cabin, but all the others in the area use wind and solar, then an inverter and AC power. No amount of explaining how much energy is lost in the inversion, etc, makes any difference. People want AC and little black boxes on their electronics cords. It won’t be an easy sell. Personally, I prefer DC (we use 12 volt since there are all kinds of devices that run on 12v systems). It’s easier to understand and you can set up your own 12 volt system.

    Dependence on the grid will remain, I think, because people simply do not want to learn how to deal with electricity. Solar and wind on a personal level requires troubleshooting, constant maintenance, etc.

  130. Lemonade says:

    I see The NYT has posted an online correction underneath the oped but it’s not the error you mentioned on MediaBugs (and here).

  131. steverichards1984 says:

    @Massimo PORZIO,
    A PV panel is just like a battery, if you decide not to use the potential within a battery, you do not and the power is available for another time.

    If you do not make use of the voltage produced by a PV panel then you don’t, and need worry no more.

    Inverters are designed to make the most of the output from a PV panel, they constantly adjust how much current to take because when you take more current, the voltage falls slightly.

    The inverter produces as much power capacity as it can, if you do not wish to use it at anytime, don’t, the inverter will take less from the panel.

    There is no need for resistors or other loads.

  132. Steve Richards says:

    @Massimo PORZIO:
    Your “breaking resistors” are used in motor drive systems, when the inverter has stopped providing power to the motor, the load (a machine, a conveyor belt etc) runs due to kinetic energy and you want to stop it by allowing your motor to run as a generator, provide the generator with a load, ‘breaking resistors’ and your machine will come to a stop as the ‘breaking resistors’ absorb the power of your machine.

    In cars etc they call it regenerative breaking, where the generated electricity is fed back to the battery rather than wasted in resistors.

  133. Massimo PORZIO says:

    @Steve Richards
    “A PV panel is just like a battery, if you decide not to use the potential within a battery, you do not and the power is available for another time.”
    False: the unused power is converted in heat by the junction of the solar panels that, when irradiated by the Sun, increase the voltage at their contacts this voltage higher than the nominal P-N junction at the environmental temperature generate the current across the junction which heats up the panel, this way the panel works as the breaking resistor I referred.
    “The inverter produces as much power capacity as it can, if you do not wish to use it at anytime, don’t, the inverter will take less from the panel. There is no need for resistors or other loads.”
    Yes, you are right here. No need for them, because the panels themselves dissipate the unused power heating up.
    But heating up they lose efficiency.

  134. steverichards1984 says:

    @Massimo PORZIO:
    I feel that we are getting closer!

    There is no mechanism that I know of for an unused PV panel to heat up other than by direct application of the suns rays. In just the same way that a plate of steel would warm up if exposed to the sun.

    If it is not providing electrical power, its temperature depends upon the amount of power from the sun and the figure for its reflectivity (or albedo if you wish) plus other heat transfer mechanisms such as conduction and radiation.

    Now, when you draw current from a PV panel, the panel will experience a temperature rise due to P=VI or P=I^2R etc.

    The more power extracted, the warmer the panel gets.

    I agree that the warmer it gets, the less efficient it becomes.

    Still no breaking resistors though.

  135. Massimo PORZIO says:

    Hi Richard,
    Not really so, The more energy you convert to electricity and extract from the PV the more it cools.
    If you leave the produced current there on the panels electrodes without using it, that current is converted to heat. The temperature rise due to the Joule effect you refer exists but its another issue.
    Energy must go somewhere, if the inverter doesn’t sink it from the panels they became more warm than otherwise.
    This is the reason I don’t agree with your “A PV panel is just like a battery, if you decide not to use the potential within a battery, you do not and the power is available for another time.”

  136. steverichards1984 says:

    @Massimo:

    You will have to give me a technical reason as to why PV panels cool when in use, it does not make sense to me.

  137. dmacleo says:

    I have generator set here inn outbuilding with no isolators. I also follow a well defined procedure.
    if power out I first flip main breaker in house to OFF.
    I then go out to incoming at meter and flip that breaker to OFF
    I then start gen and let it stabilize by running a light in outbuilding, its well ventilated.
    I then flip the 220 breaker to send power back to house.
    but house still has nothing because, yup you guessed it, there is a fourth breaker that needs to be flipped on to allow power to go into panel.
    can run heat and water pumps ok, nothing fancy but when its below 0 F and power is out you need heat. actually I can run anything I want but gen is getting old so I do not push it.

    when I see evidence that power is back on, which in rural maine is hard to do actually, I then shut off the breaker from outbuilding to depower the panel.
    then I flip breaker in outbuilding to remove all draw from gen, let it idle a few and then sut it down.
    I then flip the breaker on meter on and then flip main on inside house.

    under NO conditions is the generator running w/o the 2 breakers to utility being thrown and isolated. even when just starting the gen to run it a few for checks I will not do that.

  138. Massimo PORZIO says:

    @steverichards1984
    Hi,
    maybe I’ve been not clear, I try to explain now.
    Any photo-voltaic panel is made of P-N semiconductor junctions. Any semiconductor junction present a nominal voltage at its extremities which is function of the environment temperature. If you apply to the P-N junction a voltage equal or greater than its nominal value the P-N junction allow a current to flow through it. This is the very same behavior of a directly polarized semiconductor diode. For diodes, that nominal voltage is named Vf which stand for forward voltage. The P-N junctions of a photo-voltaic panel when exposed to a considerable flux of radiation which wavelength is close to the Planck’s black-body of the material which the P-N junction is made (for silicon it’s around 850-950nm) the P-N junction starts to exhibit a voltage. If that voltage rise over the nominal voltage of the junction polarizes it directly making a current flow across the junction. If instead you connect an external load to that junction, the current will flow in the load avoiding that current in the P-N junction which cools respect if it was unloaded.

    By the way, just imagine the solar panel as a close system which receive the energy from the Sun. Since it’s albedo is independent by the load connection or not, that system must release the energy in one way or another, otherwise you should identify a work on the panel structure which justify the accumulation of energy along the exposition time. Since that work doesn’t exist at all, the only way it has to release that energy when no load is attached is heating up (that’s the thermodynamic work indeed of course).

    An another example:
    imagine to put the solar panel with a resistive load attached to it, both into a greenhouse. Then the Sun heats up all the inner thing of the greenhouse at a temperature that depends only on:
    A) the solar flux which impinges the greenhouse
    B) the greenhouse glasses transmittance in the solar radiation band,
    C) the inner objects albedo
    D) The greenhouse walls insulation coefficient.
    The inner temperature it’s absolutely independent by the fact that the load is connected or not to the solar panel, because there is no other energy than the solar radiation that enters the greenhouse. So, when the load is disconnected the solar panel must be warmer than when the load is connected otherwise there is creation of energy, that we know is impossible.

    By the way the reason a PV lose efficiency when its temperature rise it’s also because its nominal P-N junctions voltage decreases as the temperature increase.

    I hope I’ve been a little useful with the above.
    Sorry, my English is not so good.
    Have a nice day.
    Massimo

  139. Massimo PORZIO says:

    Hoops! I wrote:
    “This is the very same behavior of a directly polarized semiconductor diode”
    No, it’s “This is the very same behavior of a INVERSE polarized semiconductor diode”, because it is the current of recombination of the charges into the depletion layer of the junction.
    (It was about 2:00AM here in Italy and I was very tired, sorry).
    It is the very same current experienced in the zener diodes, which is very high in the case of the PV junction because they are made with highly doped semiconductors to get the direct resistance very low.
    Have a nice day.
    Massimo

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