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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David Larsen

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.

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

BrianJay

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

“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.

BradS

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.

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.

Steve from Rockwood

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.

john robertson

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.

AC

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…

ShrNfr

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.

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?

bob

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

Mike M

“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

Doug Huffman

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

Paul Westhaver

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?

Bloke down the pub

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.

RHS

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?

Ken Langford

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

Doug Huffman

@”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.

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.

polski

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?

DR

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?

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.

Billy

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.

Graeme No.3

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.

Leonard Weinstein

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.

theduke

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.

Frank

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?

Paul Westhaver

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.

Doug Huffman

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.

theduke

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

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.

Bill Taylor

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.

jmdesp

@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.

MarkW

“Having spent our careers in and around the power industry”
What does this mean? That they can see power lines from their front porch?

MarkW

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.

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

RockyRoad

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.

john robertson

@ 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.

Scottie

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

Gunga Din

““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.

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.

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.

Kev-in-Uk

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!

Paul Westhaver

mark w…
exactly.

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.

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.

theduke

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.

Chris @NJ_Snow_Fan

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.

RS

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.