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StevePxxxxxxxxxxxxxxxxxx
I've read that the cost of the PV panels is less than half the installed cost of ...
Solyndra: Its technology and why it failed
Rich Pell
11/21/2011 7:30 PM EST
Electrical performance
Electrical performance
What about the electrical performance of the solar cells? As electronics professionals, we tend to focus on this rather than the secondary aspects of marketing or mechanical design. In terms of energy harvesting performance, Solyndra promised that cylindrical modules required only their shape to track the sun rather than costly mechanical systems. They reasoned that a curved surface would collect rays at all the sun's angles throughout the day.
Figure 2: The module construction employed by Solyndra is revealed in this cross-section view showing the inner tube coated with the photosensitive CIGS thin film covered with a coupling element to provide a light concentrating effect.
Without data to compare side-by-side, we should be slow to judge. But to a first order, it appears questionable that the cylindrical modules could actually achieve what was advertised. The sun passing across a fixed flat surface definitely produces a constantly varying angle of incidence. Peak output occurs during a relatively short portion of the day as the ray angle is perpendicular to the solar cell surface. Solyndra cited this as their key differentiator.
There is no disputing the fact that the sun strikes the surface of a curved solar cell at right angles throughout much of the day. However, the surface area subjected to this optimal angle is extremely small compared to a flat panel leaving less photovoltaic material exposed to strong sunlight for energy conversion.
Solyndra's process of forming the solar cell material over 360° of the tube along with the gaps between the tubes enabled the harvesting of light passing through the panel and reflected from the surface behind. Although a reflective backdrop improved power output from the Solyndra panels, it is difficult to make a case for their design compared to a panel with 100% fill factor capturing only incident light. There would be little to be gained by leaving large gaps and collecting reflections compared to simply covering the area receiving the direct sunlight.
Figure 3: This Solyndra marketing graphic was used to highlight the ability of the tubular design to accept light through a full 360°.
Solyndra marketing materials pointed to the improvement in solar energy harvesting early and late in the day compared to a crystalline silicon flat panel. If the solar panels were directly tied to a load, a longer window of useful energy would be a big advantage.
Solyndra's datasheet compared output from a standard crystalline flat panel with 15° tilt to their tubular design. Although the Solyndra output was strikingly higher both early and late in the day, peak output at midday was lower than the crystalline panel. The net effect was an increase in total daily energy supplied by the Solyndra panel, but the improvement was only 7%.
Without an independent comparison test, we cannot be entirely certain, but the comparison of outputs even as shown in Solyndra's own marketing collateral was not compelling enough to warrant a much higher price tag for their panels. With feed-in-tariffs in effect, the goal is to sell the most power back to the utility company. That was Solyndra's prime market, but their design offered only a mild performance benefit.
The tubular design for Solyndra solar panels forced them to focus on some niche markets. There is no doubt that their panels allowed light through. One angle was the energy collected after reflection from the surface behind the panels.
Looking to situations where there is value in allowing some light through, Solyndra attempted to market the tubular module concept to greenhouses. They took that one step further to position their product for greenhouses in climates where partial shade is advantageous. Solyndra panels would provide the perfect protection for plants growing underneath while producing electrical energy for greenhouse operations (http://www.solyndra.com/technology-products/greenhouse/).
Next: Non-technical factors
Electrical performance
What about the electrical performance of the solar cells? As electronics professionals, we tend to focus on this rather than the secondary aspects of marketing or mechanical design. In terms of energy harvesting performance, Solyndra promised that cylindrical modules required only their shape to track the sun rather than costly mechanical systems. They reasoned that a curved surface would collect rays at all the sun's angles throughout the day.
Figure 2: The module construction employed by Solyndra is revealed in this cross-section view showing the inner tube coated with the photosensitive CIGS thin film covered with a coupling element to provide a light concentrating effect.
Without data to compare side-by-side, we should be slow to judge. But to a first order, it appears questionable that the cylindrical modules could actually achieve what was advertised. The sun passing across a fixed flat surface definitely produces a constantly varying angle of incidence. Peak output occurs during a relatively short portion of the day as the ray angle is perpendicular to the solar cell surface. Solyndra cited this as their key differentiator.
There is no disputing the fact that the sun strikes the surface of a curved solar cell at right angles throughout much of the day. However, the surface area subjected to this optimal angle is extremely small compared to a flat panel leaving less photovoltaic material exposed to strong sunlight for energy conversion.
Solyndra's process of forming the solar cell material over 360° of the tube along with the gaps between the tubes enabled the harvesting of light passing through the panel and reflected from the surface behind. Although a reflective backdrop improved power output from the Solyndra panels, it is difficult to make a case for their design compared to a panel with 100% fill factor capturing only incident light. There would be little to be gained by leaving large gaps and collecting reflections compared to simply covering the area receiving the direct sunlight.
Figure 3: This Solyndra marketing graphic was used to highlight the ability of the tubular design to accept light through a full 360°.
Solyndra marketing materials pointed to the improvement in solar energy harvesting early and late in the day compared to a crystalline silicon flat panel. If the solar panels were directly tied to a load, a longer window of useful energy would be a big advantage.
Solyndra's datasheet compared output from a standard crystalline flat panel with 15° tilt to their tubular design. Although the Solyndra output was strikingly higher both early and late in the day, peak output at midday was lower than the crystalline panel. The net effect was an increase in total daily energy supplied by the Solyndra panel, but the improvement was only 7%.
Without an independent comparison test, we cannot be entirely certain, but the comparison of outputs even as shown in Solyndra's own marketing collateral was not compelling enough to warrant a much higher price tag for their panels. With feed-in-tariffs in effect, the goal is to sell the most power back to the utility company. That was Solyndra's prime market, but their design offered only a mild performance benefit.
The tubular design for Solyndra solar panels forced them to focus on some niche markets. There is no doubt that their panels allowed light through. One angle was the energy collected after reflection from the surface behind the panels.
Looking to situations where there is value in allowing some light through, Solyndra attempted to market the tubular module concept to greenhouses. They took that one step further to position their product for greenhouses in climates where partial shade is advantageous. Solyndra panels would provide the perfect protection for plants growing underneath while producing electrical energy for greenhouse operations (http://www.solyndra.com/technology-products/greenhouse/).
Next: Non-technical factors
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kc6zut
11/21/2011 4:30 PM EST
"No wrongdoing has yet been uncovered despite a huge waste of government money." Shouldn't that read taxpayer money? Just my $1.90;-)
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anonymous user
11/21/2011 4:59 PM EST
So why could'nt Solyndra use a rolling process to also make conventional panels either on glass or film with minimum labor force? The american solar folks perhaps should creat a process that uses automation and streamline mfg? That's what brought fiber optics cost down and volume up + performance..in the USA.
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anonymous user
11/21/2011 5:24 PM EST
HYBRID COLLECTOR! I've been installing pv solar and solar thermal since 92. We've been waiting for someone to produce a collector that combines PV with thermal collection. If Solyndra had only thought to flow coolant thru those stupid cylinders! Thermal collection can get as much as 80% of solar energy. In this hybrid collector scheme, PV electricity is useful but will always be the lesser product, due to the well known theoretical limitations (the einstein photoelectric equation, etc).
Plus: cooling of a PV collector increases its output power by 15% in the southwestern summers.
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pcsalex
11/21/2011 5:34 PM EST
Solyndra is the best example for that, that real engineering studium is still needed, as you could see from that article if somebody has the right back ground lots of money could be saved, in case Solyndra 500 milion USD, for that you could pay many ongoing engineers tuition.
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anonymous user
11/21/2011 5:47 PM EST
All one had to do was to look at the amount of vacant available commercial real estate in CA and recognize that the when Solyndra (a start-up) elected to build their own mammoth factory from scratch that these were spend thrifts of the highest order.
Solyndra's multimillion-dollar white elephant
ENERGY
Spa showers, glass-walled conference rooms - and robots to help in the factory
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anonymous user
11/21/2011 6:26 PM EST
Thanks for the article that addresses the real problems with Solyndra.
Why didn't our Secretary of Energy, Dr. Steven Chu, who has a PhD in physics, do some relatively simple observations, investigations and calculations that would have clearly shown that the Solyndra claims for both increased energy output and lower costs were largely bogus?
Perhaps Dr. Chu thinks his job ". . . helping implement President Obama's ambitious agenda to invest in clean energy, reduce our dependence on foreign oil, address the global climate crisis, and create millions of new jobs . . ." can overcome the laws of physics and economics?
Many of us working to develop alternative energy technologies for the last 30 years did not believe in the magic of making a round solar panel, regardless of the hype.
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anonymous user
11/22/2011 12:38 AM EST
Please, don't dump the whole idea of employing a clever combination of cylindrical cell and solar illumination. A panel with a good number of transparent cylindrical tubes, which internal surfaces are covered by sun light sensitive coating (wide gap metal oxide films impregnated with clusters of noble metals), can be used as an highly effective device for photo-decomposition of different organic contamination in water (industrial water purification).
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anonymous user
11/22/2011 12:58 AM EST
Solyndra did a very good job to commercialize CiGs which will one day take solar costs much lower. What I don't understand is how they fooled so many people and especially our government into believing that hope and hype are more important than data and facts. PV prices have been dropping for years. This year was exceptional, but it was clearly coming as capacity was building up. The big players have big production sites (over 1 GW). Until someone comes out with a panel or other technology that already meets or beats First Solar, don't believe their hype. The US government (meaning us) were hoodwinked here. I applaud the intent, but this was a big, big mistake.
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anonymous user
11/22/2011 10:25 AM EST
As an old power plant engineer, who assessed advanced technology in energy, for a life time, I found this article fascinating from a expert's view point. However the problem, in energy, rests on one characteristic, cost. Solar will always be more costly than energy derived from the combustion of carbon, or the fission of uranium, for base loaded supply. It is not a little more, it is a lot more. The multiple is difficult to define due to financial gimmicks, subsidies, mandated purchases, taxes, and hostile regulation on the competition. On an apples to apples comparison, I would guess about five or ten times. Solyndra never had a chance, if the market had been allowed to function.
The fact that our government has its thumb on the scales of commerce is another problem, dictatorship. I worry more about the loss of our freedom than cylindrical solar panels.
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anonymous user
11/22/2011 11:45 AM EST
The article is good, although not quite correct in all respects. Most of the comments are way off base, unfortunately.
1. Solid panels laid flat on a roof still require a racking system, as the lift effect of wind will tend to suck them off the roof. The Solyndra system was by far the lightest, at about 2.8 PSF, solution available for rooftops. Many commercial rooftops have a rather small margin of safety for added weight - a polite way of saying the buildings are cheaply built.
2. The author is right - cost is the key element. Solyndra thought it could get the costs down, way down. Not an altogether unreasonable idea - fluorescent light bulbs (the old style straight ones - are pretty cheap, and there are similarities.
@RL: Solar may or may not alway be cheaper than fossil. I don't think fossil fuel prices will go up, but solar income form could come way down, if someone makes a major breakthrough in either cost or efficiency.
@Louis: Solyndra did know prices would drop. In early 2008, the industry saw the price curve dropping below $5/watt and, maybe, headed for $2/watt. I don't think anybody believed it would drop to $1/watt by mid-2011.
@Gerald: Solyndra's claims for increased energy output were not bogus. I've seen reams of real-world test data comparing Solyndra and other panels, side by side, in the field, and Solyndra panels performed as advertised. They were cheap to install, too - much cheaper to install than racking and flat panels. Solyndra just couldn't get the production cost down fast enough.
@Richard: Perhaps you don't realize that about 90% of Solyndra's new building is a semiconductor fabrication facility. There are lots of empty buildings in the Valley, but few if any are suitable for construction of a fab. Solyndra's first factory had been a fab - the old HMT plant (and others, I think - hard to remember them all). Most of the cost of the new plant was the specialty plumbing that fabs need. All-welded stainless-steel plumbing, for example, does not come cheap. There were tens of millions of dollars just for that.
Contrary to press reports, the small amount of the building that housed offices was not especially deluxe. Yes, they used glass plates to subdivided managers' offices and conference rooms from the area where the cubicles were. Part of this is LEED - it lets daylight illuminate the cubicle area. I've been in many office buildings in the Valley, and the Solyndra building was about mid-pack in terms of 'fanciness'.
The 'spa' showers are another press fantasy. As I mentioned, the building is a fab - that is, a clean room. Showers are provided, as in any semi fab that I've ever been in (and that is a long list). For safety reasons, the shower water temp is preset. OSHA doesn't want anyone scalding themselves. The temp is displayed on an LCD panel. Kinda like your typical household thermostat.
There were numerous robots, of course. Did you think each panel was carefully assembled by hand? Robots build darn near everything these days. Most were standard Kuka robots. One robot was a little cart that moved WIP from one area to another. Yes, it played stupid little songs. It was required to, as a warning to humans that this automated vehicle was rolling down the corridor. This was neither fancy nor deluxe. ACtually, if you worked near it, it got pretty old, pretty quick. But again, an OSHA-mandated safety requirement.
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anonymous user
11/22/2011 12:49 PM EST
One thing to keep in mind is that before it happens you never know.
If you went back in time and told people who would win and who would lose in most industries they would not believe you.
Who would have believed in the apple II days that microsoft would be bigger than apple? Who would have believed in the windows 95 days that apple would again be bigger than microsoft?
Solyndria was different and appeared to have unique advantages/differences. If only lighter per square foot that could be the most important thing if office/factory roll out were the key delivery method.
When planting seed farmers put a little seed everywhere and some of it grows. Thats the nature of investing and why mutual funds and indexed funds are a better idea for most people.
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anonymous user
11/22/2011 9:29 PM EST
There is another major factor in a flat solar panel that would be at the very least minimized by the Solyndra's round design.
That is the effect of dust and water spots obscuring the panel.
This dust and spotting of a flat panel can lower its output drastically.
A round solar colector should avoid water spots almost entirely.
Dust should be greatly minimized also.
My guess is Solyndra's manufacturing equipment is on its way to China ware it will be used to make ton's of cheap solar panels.
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anonymous user
11/24/2011 4:04 PM EST
Solyndra management and Board of Directors are disgrace to America. Their actions will affect the entire solar industry for a very long time.
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ablazev
11/28/2011 2:10 PM EST
Dr. Chu, who authorized the loan for Solyndra's flimsy, inefficient and unproven PV technology should see this article. Maybe he can learn something from it.
Dr. Chu should also learn something about the equally flimsy and inefficient--but even worse; toxic and carcinogenic--CdTe technology he is supporting and giving $$$ billions to now days.
We'll hold him responsible for the Solyndra's failure, and for the upcoming poisoning of thousands of acres US desert land.
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anonymous user
11/29/2011 1:31 PM EST
FYI, George Grenley is the President Plans2Reality a Technical Marketing Company of Solyndra. THat does not mean we should dismiss his comments, just keep in mind his point of view.
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anonymous user
11/29/2011 1:51 PM EST
The article begins by asking, "Will this story become a parable for America's waning competitiveness?" And while the solar industry is no acception for the need for market competitiveness, this story will become a parable for the Obama Administration's association with crony capitalism as a means for social engineering and campaign fund raising.
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Peter.Born
12/2/2011 12:31 PM EST
Private venture capital investors thought Solyndra was solid, and invested over $1 billion — twice the support provided by the federal government. Please leave the "Crony" comments to the amateurs.
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anonymous user
12/2/2011 12:50 PM EST
The primary selling point for Solyndra's technology was not that it was cutting edge nor inexpensive; it was easier to deploy and maintain than the commercially available PV panels. That makes them portable, which is a big plus for military applications. It doesn't matter that the cost of energy produced by Solyndra's technology is pushing $7 a watt, because the technology could be adapted to the field. The government basically bought Solyndra with a loan guarantee because the military needs their technology. Mil-Spec devices are never cheap.
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EG_RealWorld
12/4/2011 4:12 PM EST
Don't discount better mouse traps - better means better and it does not mean high technology unless it is needed. The whole Solyndra concept looked questionable technically. To think an array of tubes do not need to be secured for heavy winds is ridicules. Tubes instantly sound less efficient despite all of the sales hype. Get the engineering correct then bring in marketing.
Yes, for the next well developed product long it would help if the government would protect any U.S. manufacture from foreign dumping and un-equally applied pollution and EPA regulations. Foreign manufactures should be fined for violations no-mater where in the world the pollute.
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anonymous user
12/8/2011 9:37 PM EST
Solyndra's technology was good, but it was the installation that was brilliant. In Florida, where storm events drive the cost of panel installations on commercial roofs requiring through bolt installations, the Solyndra system would have been ideal and would have made up for module cost in installation savings.
Unfortunately, the Florida legislative structure favors utilities and prevents the adoption of solar power as much as possible. We did not have the opportunity to take advantage of this ideal product, since PPAs are yet to be permitted. Unfortunately for Solyndra, our time did not come to save this innovative product. We hope our legislators do wake up.
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StevePxxxxxxxxxxxxxxxxxx
12/13/2011 1:33 PM EST
I've read that the cost of the PV panels is less than half the installed cost of a PV system. It sounds like the Solyndra design could lower the installation costs.
It might be more interesting to see a chart of the cost of the installed systems rather than a chart of panel costs.
It seems if you don't need to drill mounting holes into a flat roof(most industrial buildings) there would be a time savings and a longer term maintance savings. Fewer leaks from the holes and when it's time to resurface the roof just move the panels to one side out of the way.
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anonymous user
3/2/2012 5:28 PM EST
Thanks to Don Scansen for the excellent article.
This insight into some of the technical and manufacturing aspects of the Solyndra approach to solar power was very valuable.
It is evident that the economic factors, i.e subsidized imports, are the prime game changer here. Perhaps the loan guarantees were really OK, and in fact we (USA) have failed miserably to compete on par in this economic arena, by not controlling unfair competition via the appropriate import quotas/tariffs.
Perhaps some of our federal defense dollars should be spent on judicious economic warfare.
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