Regarding this article, I think I’ve found a simple reason for this failure, and the reason will shock and surprise you.
In the article, a news report by TV station WFTS is cited:
WFTS News in Tampa obtained copies of the courthouse’s electricity bills and confirmed the savings are no more than about $2,000 per month. WFTS also confirmed the panels are reducing electricity bills by only 15 to 18 percent, instead of the promised 40 percent.
You can watch the news report here.
They say a picture is worth a thousand words, I’ve got one of those. First, look closely at the picture in the news story above…now look at this picture and note the arrow.
I think the government dufuses and the solar company missed the shading from the nearby tall building (the Hillsborough County Center Building), seen in the photo above which you can inspect yourself at Bing Maps here: http://binged.it/1tqPjnf
It looks like a little over half of the panels would be in the shade during the afternoon based on my comparison to the article photo, a larger version which exists here:
Source: http://www.naco.org/newsroom/countynews/Current%20Issue/10-18-10/Pages/OldMainCourthousesolarphotovoltaicproject.aspx
That afternoon shade will kill solar panel efficiency big time. The problem will be greater in the winter, at low sun angles, further reducing the efficiency of solar panels which appear to be placed flat on the roof, rather than tilted for maximum efficiency. In fact if you watch the WFTS i-team video, you’ll see that the panels are in fact laid directly on the roof surface. Here is a screen cap showing workers placing flexible panels flat on the roof:
The effect of array tilt angle on solar PV energy output may be up to 20% compared to that of flat installations, depending on latitude. Typical rooftop arrays with tilt look like this:
![Piscataway-Conackamack[1]](https://wattsupwiththat.files.wordpress.com/2014/08/piscataway-conackamack1.jpg?quality=83)
You can read more about tilt angles and panel efficiency here.
But the tilt issue is small compared to the shading issue by the tall building to the Southwest. using Google Earth’s timeline feature, I found an image from Dec 26, 2012 that shows the peak shading near the winter solstice, it also shows the solar panels in place. Clearly, the shadow will cover a significant portion of the solar panels on the roof for a period of time.
The next thing that needs to be done is a public records request to get the hourly solar power system output data over the past couple of years, it should be an easy matter then to note when the output drops significantly, and to line that up with sun angles and times.
On a daily basis, you can watch the real-time output page here:
Source: http://www.hillscty419piercepv.com/
Below the big dial gauge, if you choose “select gauge” and the “Interval 2-hour Avgs.” you’ll get a bar graph plot of solar output by hour, though there is no facility for getting anything but today’s data. From my observations, it seems that at this time of year, we get a bigger drop-off in production in the late afternoon than we should, which should be almost symmetrical with the buildup in the morning towards peak insolation. The afternoon production seems to have a larger gap.
It will be interesting to see what the public records request for the hourly solar power output data brings.
Full disclosure: I have a solar power system on my own home.
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As far as the shortfall in production goes, I don’t think the shadow is a major part of it. It probably masks ‘up to’ half the roof for most of December and early January. With those long shadows even the illuminated sections will only be about 50% peak at mid-day due to low incident light. I doubt it costs more than 5% of annual, if that.
What is more important is with the sun high now it only near 75% peak at high noon.
This is very likely due to high panel temperatures amplified by flat non-ventilated mounting.
That could account for a shortfall of 25%. The rest of the shortfall probably comes from ‘optimistic’ estimations provided by the enterprising enterprise that sold them the system.
They certainly made a packet rolling out the black mats and plugging it all in.
Perhaps Anthony knows some on-line tools for cost estimation of a grid-tied system of this surface area. As a very rough guess, at current prices thin-film about 60c/W add $1 per watt for accessory hardware….. $300k
The resting going on wages, executive bonuses and kickbacks … yeah, $1.2 million would be about right. 😉
Even best case I am not getting the financial math.
Best case it is 20 years to break even at the $1.2 million investment.
Invest the $1.2m in a simple savings account (with current miserably low interstest rates) and after 20 years of compounding you have earend Florida tax payers $1.1 million.
To summarize – Solar panels 20 year return, zero dollars. Simple savings $1.1 million.
I guess the argument is there are environmental benefits. Fine, even accepting that, it still is completely dishonest to suggest there is financial benefit. I am not sure why these people are not in jail.
Clue: they are the courthouse, the ones who decide who goes to jail. 😉
The finalcial maths is simple. None of this is about ROE. It is about yet another way to bail out the banks.
A domestic solar installation has a guarnteed revenue. If you have a revenue, you can ask for a loan. When a bank grants a loan, it creates 90% of the money it will lend you from nowhere, thus creating “wealth” and raising the banks assets.
Thermal solar is far more efficient than PV if you want to save energy but it does not create a revenue stream and bank loans. That is why even in the UK where the amount of sun won’t even get you a tan most years, they are pushing domestic PV in installations that do not even have a metre to measure what they are feeding into the grid. You just get paid a forfeit rate.
They know it’s not worth measuring and would be an embarassement that everyone is going to see, so they don’t install metering.
I read an interview with a fire chief who said the panels on a roof are so dangerous to his men that he won’t send them onto a roof during a fire–but fighting a fire from the roof is crucial. The problem is that the panels are very difficult to disconnect from the power. They also add weight to the roof which is also dangerous. win-win all around: useless and dangerous.
@ur momisugly profitup10 on August 30, 2014 at 2:21 pm:
Didn’t you notice your cut-and-paste listing came through with crap links that didn’t work?
Notice how no one bothered to tell you yesterday they were crap, indicating there was very little interest in your long cut-and-paste listing anyway.
If you can’t take the time to get working links, don’t bother to hack up someone else’s stuff from elsewhere.
Sorry about the links that were not complete – I have now given root links so you can read all you like. \
http://www.renewableenergyworld.com/rea/news/article/2014/05/german-wind-industry-leaders-why-
energiewende-works-and-offshore-is-growing-up
http://www.renewableenergyworld.com/rea/news/article/2014/05/german-wind-industry-leaders-why-energiewende-works-and-offshore-is-growing-up
http://www.spiegel.de/international/search/index.html?suchbegriff=+German+Energy+Revolution+Der+Spiegel
http://www.forbes.com/sites/larrybell/2013/08/13/german-green-energy-bluster-running-out-of-wind/
Forbes links require clicking on other links inside the posted link.
Now I guess you can show all how informed you are – attacks on persons shows a complete lose on the topic being discussed. I provided links for some that desired to LEARN – evidently you already know it all?
LOL
And as you think you have attacked me with your witty reply, by your stated rule you must think you’ve had a complete loss on the topic being discussed.
Meanwhile I’ve made you take responsibility for your actions, you’ve not only apologized for the bad links but supplied good ones.
I shall refrain from ending this comment with “LOL” despite really wanting to do so.
Have a nice day.
Point being made is that there is abundant proof that solar and wind are not up the desired standard and there is no current technological advances available to repair same. Yes, like in the article it the Government that is blowing our tax dollars on poor research and selecting bad energy production methods.
Mostly Cloudy, Temp: 89F, Humidity: 63%, Wind: 7 mph
Wasn’t that yesterday’s “Current Conditions” as well? Ah heck, I seem to recall that was also the overnight conditions.
For added fun, the EcoSolar people decided to make the web site a Flash object, which conveniently prevents anyone from copying and pasting the displayed info. You might be able to do screenshots, but a programmer could have faked up what the monitor was showing, and as the display shows the computer user’s time and not that of the monitoring system it’s therefore not definitive.
Yup, nothing screams “honesty and accountability of government” like making sure your vote-getting newsworthy Green project doesn’t voluntarily disclose evidence admissible in a court of law.
Anthony,
The Flash object’s link went to http://www.dmssvr.com/dmsmon/mon/?id=1834
Shortening to the home address got a redirect for Data Monitoring Solutions:
http://datamonitoringsolutions.com/
Halfway down, they show the “real time monitor” as a product, the sample image has a NOAA logo. Wow, it’s used on federal government solar projects, most impressive.
Main page has a Free Demo Monitor offer displayed. Sure, on mouseover it says “Solar Power International 2012 Special Offer”, but it has to be good or they wouldn’t show it, right? I wonder what the main solar project of “Watts Worldwide Weather” would look like…
This makes me laugh. I put up some solar panels a few years ago, mainly to help pay for airconditioning. AC added roughly $5-600 a year to the electric.(thanks all for your generous help!) Part of the process was getting the site certified by the electric company. The guy that did that had a neat little gadget to measure insolation and compare it to the expected value for the day and time. Then he had to add in corrections for panel angle, exact azimuth, and shading. The house faces almost due south, the roof is 40 deg and there is ABSOLUTELY NOTHING than can shade in now or in the future. But he still added a small correction for the trees on the horizon.
The fact that no one apparently considered shading should be enough to put the county officials, the government folks that announced this”$Green” project in jail, and any engineer involved should lose their license. So woefully typical of magical “$Green”, which must mean the green of dollars.
This just gets better.
On a lark I did a WHOIS of the Flash object’s home site, see what dmssvr-dot-com (DMS server) dredges up.
DiveBum Studios does ‘Film Production, Photography, Visual Design’. Looks like they’ve filmed and produced some nice nature specials, as well as golf course and yacht videos for marketing.
Is it just me, or do those dates really most likely show they only did a one year renewal on a domain which provides monitoring services for multiple government and business installations that will be around for decades with multi-year contracts?
WHOIS datamonitoringsolutions-dot-com:
WHOIS hillscty419piercepv-dot-com:
That sample graphic I posted earlier used idssvr-dot-com.
I’m sensing there might be a trend there.
yes, earlier I did whois on the defunct domain behind the links like “solar education center” that fail to connect for me. Same bum behind the name.
I also tired to find the web site of Eco Solar to get some more info about what kind of installation this is at Tampa. Pretty hard to find but enventual it lead to ecotechnousa.com which seems to sell beds now.
I guess after the $1.2 mil for the courthouse funds dried up.
Bummer.
just tried unplugging the connection. The “real time monitor” keeps spewing out fake output. The speedo is still twitching up and down the Today, This week and This month counters are still dutifully pretending to show “real time” totals, despite having been cut from the net.
Look at source for the page in click through to the src of the flash; there you’ll find, line 70:
‘play’, ‘true’,
‘loop’, ‘true’,
This whole interface is a total fraawd. It’s a con.
Like I pointed out right from when I started logging it, the “real time” readouts show impossible results: negative power or power 5 times the boilerplate max.
They seem to be doing some linear interp between last and current values and adding some random variation to twitch the readout and make it look “live”. The trouble is, if you log it too often the random change take the incremental power outside what is physically possible.
LOL
One more thing, the random numbers added to make the false ‘live’ data do not seem to be mean zero. They are 0 to N values. This explains why the speedo hovers around 4%-5% above what the kW counter shows.
currently 138.5 hovering 74,75% should be 70.7% . This has been consistently the case since I started looking yesterday.
Turn on “info hotspots” and it tells you the speedo is supposed to “demonstrate photovoltaic’s capabilities over other systems….”
Yes, the “meter” was bobbing up and down at 3 a.m. Tampa time, just like a real meter. There were some very low (down to 12%) excursions during the late afternoon that could be attributed to clouds, but overall, it looks like the programmer was told to go to Florida and Tampa with the algorithms to make the meter look more metery than it really is.
I now have proof that the whole “real time” thing is a fake, otherwise it would stop moving once the connection was cut.
The hourly, daily and monthly counter and the speedo are false values created by adding a probably random number in ActionScript.
The two-hourly average display option may be real as are possibly the “AC kW output” figures that do come from the server every 15 minutes.
The time is off the local PC clock, not the serveur. If your PC clock is off the “time” in Florida will be wrong too. The weather conditions displayed are the day’s weather forecast that seems to be pulled in once or twice per day. Yesterday’s “mostly cloudy” seems to have been clear skies unitl about 16:48 EDT. Clearly this is based on whether _forecasts_ not weather _reports_. Rather beats the point of having it on a “real time” monitor.
NEWS FLASH: weather conditions have changed from “partly cloudy” to “mostly cloudy”.
Reloading the page does not even get the true current values. What is served only seems to change every 15m on the server. It is not even real time at the server.
Last three values:
time kWh kW
15:05 770 115,9
15:10 770 115,9
15:28 771 115,9
15:37 787 115,9
15:39 813 74.9
current total power for the day did not moved in 23min but it’s still claiming to produce 115.9 kW !!
Not only is it a fraud, it is a fairly poor and buggy one.
The question remaining is whether the only figures that seem reasonably credible are real or also faked .
The pestilence, is FAR worse, than just a little (or in this case, a lot) of panel shading.
Solar cell panels, operate in the forward biased photo-voltaic mode, where the silicon cell forward voltage, varies roughly as the logarithm of the solar irradiance. Typically, when loaded with the optimum load, for maximum output power, the cell forward voltage is about 0.5 volt., so you need about 30 cells in series to fully charge at maximum charge rate, an ordinary deep discharge 12 volt lead acid battery. Well you can cheat and get away with just 20 cells in series, but the maximum power output will be reduced.
So let’s go with 30 cells in series, so at full sun it will try to put out about 15 volt, but a totally flat good battery might be as low as 10 volt terminal voltage, so it will start at about 333mV per cell, from the panel, or 167 mv less than the optimum 500 mv per cell.
Now for silicon diodes double their current every 26 mv, or 60 mv for a factor of 10. So 167 mv , is 6.4 times 26 mv, so the starting current is 1/85.8 of the maximum charging current. Rather pp if you ask me.
And that is the good news. If your neighbor’s building, or the aspidistra growing over your roof, should shade even just ONE of those solar cells, and reduce it insolation from 1,000 W/m^2, down to say 100 W/m^2, well that cell will only put out 60 mv less than what all the other cells are generating, or trying to generate. Well it’s much worse than that. The battery load, is going to determine, the total panel voltage and the fully illuminated cells will attempt to generate their full open circuit voltage, which is about 0.6-0.7 volt., and they will end up reverse biasing the shaded cell, which will shut it off, and the whole string, will generate no forward current. So shadowing a single cell, in a series string, will shut down the whole string.
If you parallel, the cells instead to make a 500 mv supply, the shaded cell, will try to be 60 mv below the illuminated cells, so it will short circuit them, and waste a lot of the current they were putting out.
No matter how you arrange the cells in a series parallel array, any illuminance non-uniformity, or even unmatched cells in the array, and the weak ones will hijack the panel.
So this Tampa fiasco, is a real Bobby dazzler.
Two things wrong with that comment. This is a grid tied system not charging batteries. Second if you were charging batteried you’d be dumb to plug the panel straight in. The battery draws the panel voltage down to it’s charging voltage and your I.V product goes with it.
Read up on MPPT regulators. 😉
Well so it’s a grid tied system, that’s the first thing that is wrong with it.
So where did YOU read, that I would just plug the panel in, to charge batteries. I was merely showing what the consequences of shading are.
And I don’t need to read up on anything. There’s always some workaround fix to compensate for a bad installation design. Is it any wonder that suppliers are unable to get the costs down; and the SYSTEM efficiencies up.
If you’re lucky. “Hot spot heating” can destroy shaded cells, or cause the destruction of whole panels.
http://pveducation.org/pvcdrom/modules/hot-spot-heating
Current “best practices” is to use bypass diodes to minimize the problem. It is known among homemade panel makers to include them, commercially-offered panels are expected to have them.
http://pveducation.org/pvcdrom/modules/bypass-diodes
Well, how can there be “hot spot heating”, of a cell that is shut down because of shading. And the benefit of “bypass diodes” is spectacular. For each shaded series cell, you have the benefit, of a two diode drop loss in output voltage, instead of one.
So why not parallel each series cell, with a power MOSFET, driven by a computer program, to short out any cell that is not generating its full load voltage due to shading. The short, won’t harm the cell, and it should be trivial for any tinkerer to string all those shorting FETs to a microprocessor chip.
Personally, I would want my solar installation to be done by somebody who understands the circuit physics; after all, aren’t these things supposed to last for 30 years. If conversion efficiency is not of any interest, you can add all kinds of band aids to what is a lousy installation.
From george e. smith on September 1, 2014 at 6:11 pm:
Reverse bias breakdown. In many ways a PV cell is still a diode.
http://www.ise.fraunhofer.de/de/veroeffentlichungen/konferenzbeitraege/konferenzbeitraege-2012/27th-eupvsec/geisemeyer_2do.3.6.pdf
Google “breakdown voltage diode solar cell” and you’ll find many references for it and the use of bypass diodes to prevent cell and panel damage.
Basically already being done, without central computerization.
http://www.digikey.com/en/articles/techzone/2012/dec/active-bypass-diodes-improve-solar-panel-efficiency-and-performance
Well this is a response to KDK’s post down there referencing the Digikey paper. Well the whole history of switching power supply design, has been full of ideas for “protecting” active (and passive) devices / components, usually from reverse voltage , which could be quite repetitive, in many designs; in other words, it is not a failure condition, but happens each and every switching cycle. And the chice has run the gamut, from zener diodes, to ordinary diffused junction diodes, to Schottky diodes, and eventually to driven MOSFETS, which have zero offset voltage at zero current, but do require often floating driver circuits. It was not my intention to teach an entire course, on semi-conductor power electronics; so no matter how much I say, you or somebody else can always find methods I did not put on my course. If that gives you a kick so be it.
But back to the Digikey paper. Anybody who puts 1,000 solar cell diodes in series, thoroughly deserves to have to put a reverse protection diode across each and every series cell, and also deserves the manufacturing cost of doing that.
Well made single crystal silicon solar cells, will normally have reverse breakdown voltages, well in excess of their forward voltage.
But yes, if you use junk polycrystalline cells, with all of their local point defects, I can see that many of them will barely have a breakdown voltage greater than their forward voltage.
Reversals in series strings, is a serious problem in multi-cell batteries as well; especially with deep discharge batteries (lead acid). These cells are bidirectional, and can be charged in either direction. Now modern design does make them asymmetrical, but they still will charge in reverse.
A very simple analysis, will show that a simple charge / discharge cycling of a series string, will cause any capacity unbalance to grow like Topsy, until the battery is quite useless, even if it is not destroyed. The weakest cell will discharge first, and if the load continues, it will reverse polarity, and charge in the reverse direction.
On recharge, the reversed cell, will have to be discharged before it starts charging in the correct direction, so when the other cells are fully charged, and their terminal voltage starts rising, the charger will shut off, leaving the weak cell, even less capacity, than it had before. This will continue, until the weak cell charges to about the same half capacity in each direction, on each charge discharge cycle..
This can be prevented, if the individual cells can be isolated, and each charged individually.. The weak cell, will still discharge first, but if the load is then disconnected, so cell reversal can’t occur, and then separate cell rcharge employed, the weak cell will continue to function. It will set the end point capacity for the whole battery.
The common 12 volt car battery, is about the longest series string that is stable, over the whole range of environmental conditions (with deep discharging.
The longer the series string, the harder it is to sense the end point of the weak cell.
With 1,000 solar cells in series, I would expect it is impossible to detect the voltage drop, that designates a shaded cell, reversing, so individual back diodes would be mandatory.
So I would never put 1,000 cells in series, or even 100 cells.
And the parallel current hogging failure, is every bit as bad as the serial cell reversal failure.
I once made a “Merry Christmas”, sign out of red LEDs arrayed on a pegboard. The whole string of LEDs consisted of back to back pairs, so each LED protected its mate from excess reverse bias. Then the complete series string of back to back pairs, was connected to the 120 volt ac, with just a series mylar film capacitor. The peak operating current is set by C.dv/dt and no current limiting resistor is needed. you don’t want to have the LED string drop to be more than about half the ac peak voltage.
So I wouldn’t buy anyones polycrystalline solar panels, in fact they couldn’t pay me to cart them away.
It changed!
Formerly around 9:00am EDT:
Mostly Cloudy, Temp: 89F, Humidity: 63%, Wind: 7 mph
Now at 3:38 pm EDT:
Partly Cloudy, Temp: 89F, Humidity: 59%, Wind: 6 mph
Such spectacular Florida weather. Even at mid-afternoon with the Sun beaming down for hours on dark solar panels with little wind, with less cloudiness thus more sun, with less humidity thus lower heat content thus the air should have higher temperatures for the same amount of inputted energy, the temperature hasn’t changed!
Is there really a weather station on the roof reporting this, or is it grabbed from somewhere nearby? Perhaps a NCDC-reporting weather station at an airport?
See above, it’s back to “mostly”. This is cut from weather forecasts not weather reports.
Nope, same exact thing, at 3:38, 4:45, and now 5:12 pm EDT:
Partly Cloudy, Temp: 89F, Humidity: 59%, Wind: 6 mph
Although down to 20.4 KWh, 11% tachometer.
That’s after a 5:12:15 download by my clock. No changes of weather or output.
So, the guy sold “real time monitoring”, that only issues a report every 15 minutes.
What is the extra capacity of all those monitoring systems, processing and network, doing? Borged together into a giant distributed hacking/cracking platform? Mining Bitcoins?
What the…?
Look close, and the odometer digits are seven segment displays with decimal.
And they are turning like a mechanical odometer on an older car.
Except they aren’t, they rotate upwards to higher numbers, until when the drums of a mechanical odometer would simply keep rotating from 9 to 0 and keep going, on these displays they rotate downwards to the smaller number.
The stupidity, it burns, like sunlight in Tampa.
Why would they spin at all if this was a ‘real time’ ? They would just display the new data. It’s a all a great hoax.
I can’t really define what they are doing but if you see them going backwards it is probably because these things are going backwards as well as up.
this system produces negative power a lot of the time !!
Nah, that’s not it.
In an old-fashioned mechanical counter, the numbers are on the outside surface of a cylinder. Thus the numbers were an endless loop. The cylinder keeps turning in the same direction, displaying 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, etc.
Here the odometer displays like a flat strip of paper, after 9 it has to be run back through the smaller numbers (8, 7, 6, 5, 4, etc) to get to the new lower value.
Which in computer programming terms is stupid. But in graphics terms where the numbers really are on a virtual strip that is slid under a cutout window to reveal the desired digit, it makes sense, but still looks stupid.
On closer inspection you could be correct. I saw it go from 0 to 1 and got a glimpse of a 4.
It’s academic really since it’s all bullshit graphics dressing up the fact that there is NO new data to display. There is one update from the server every 15m. The rest is a FAKE.
Cut the network and it still carries on updating the display with fake data every second.
It’s a charade.
Reblogged this on RubinoWorld and commented:
Another green energy story of failure.
The problem is not solar energy but the people who promised cost savings without doing their homework. They need to measure daily solar insolation in the location for at least one year before they can estimate the performance of the solar panels to be installed. I bet they are marketing guys not engineers.
1:58AM EDT!
Partly Cloudy, Temp: 89F, Humidity: 59%, Wind: 6 mph
I sense a trend…
4am “Fair”
should be interesting to see whether it produces any more power under ‘fair’ conditions rather than partly or mostly cloudy.
IMO, the last two days have been basically clear skies at this location until about 4pm.
There may be masking from the aircon structures and more distant highrise buildings from about 5pm since it drops to nearly nothing.
Significant late afternoon cloud is probably very typical in this sub-tropical location.
Sunset is currently around 19:30 IIRC so 5pm is probably end of solar production anyway.
Mine is still the same. Still on dial-up, there are stretches where I am offline. I suspect I may have missed one or more weather updates, which are issued maybe once or twice a day.
Just did 10:27:20 download. No weather change.
It says Lifetime 1084.25 MWh. I wonder if that public records request will reveal DiveBum doesn’t keep the fine-grained records, only the running tallies for the displays and that “2-Hour kWh Averages” gauge.
Oh, that “Averages” thing says Sunrise: 07:07 am, Sunset: 07:57 pm.
The trend is not new – – the 70s and 80s were ripe with California projects based on tax benefits and guaranteed high per KWH forced on Utilities by Congress. All failed when tax benefits ran out.
http://www.gosolarcalifornia.ca.gov/about/gosolar/california.php
Essentially a regressive tax, just like the gas tax. Way to stick it to the little guy, greenies.