Sober second thoughts on solar cells

Just about everyone pushing civilization to kick its fossil-fuel habit includes photovoltaics in the list of renewable technologies that will be required to fill the power supply gap. And just about every week one can read about a new breakthrough that promises to make in solar cell technology cheaper and more efficient. But how reliable are those reports? Not very according to one expert.

Solar power is expensive, says the conventional wisdom. Too expensive to be competitive with oil, coal and gas. True in most places, thought not in remote areas far from the grid. I once lived on a houseboat in the Canadian Arctic that relied on one small solar cell array for electricity, for example. But in large cities, I will agree it is much too expensive.

The authors of The Clean Tech Revolution, Ron Pernick and Clint Wilder, predict that the price of photovoltaics will continue to fall and such systems will be cost-competitive as soon as 2015. Maybe. And I hope so. I mean, that would be just wonderful. In the lastest issue of Materials Today (Volume 10, Issue 11), however, Gilles Dennler of Konarka Austria GmbH says we should greet claims of breakthroughs with great caution. He is particularly skeptical of organic solar cells:

The very large choice of publishing options offered to authors and the increasing difficulty in gaining impact within the community, combined with a lack of accuracy in measuring, reporting, and reviewing, has seen a significant number of papers claiming unrealistic and scientifically questionable OSC properties and performances. 'World record' OSC efficiencies are popping up almost every month, leading the community into an endless and dangerous tendency to outbid the last report. Such phases of disharmony are not unusual in a young scientific field. But it is important to keep them short and not let them create skepticism or mistrust of the field itself.
...
Although official certificates would seem necessary for claims of world record efficiencies, all actors in the field would agree that there is also a strong need to report device performances without independent verification. The objectivity of this approach relies entirely on basic ethical rules that should lead authors to regularly question their findings and constantly push the accuracy of their measurements to the highest possible level. But responsibility also lies with editors, who should ensure a thorough reviewing process, even if the cost is a slight delay in the publication procedure or a reduced number of papers published. This is especially necessary in the case of world record efficiencies for which the highest level of scientific evaluation is required to avoid falling for the easy attraction of a newsworthy publication. This has not always been the case in the recent past.

The current outbidding phenomenon does a severe disservice to the whole OSC community, damaging its reputation. Solar cells and especially OSCs face enough difficulties in convincing people of their benefit over other energy sources. We should all act together for their success, not against it.

Still, I expect that we will be seeing more and more solar arrays on rooftops in the years ahead. Don't get discouraged guys. Just keep plugging away....

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Keep on pluggin' James!
Don't close off the possibilities of the latest Gee Whizz. Do get the engineering "bean counter" reports. The corn/ Ethanol bonanza appears to be a Bush gift to Big Agra. It needs a thorough "footprint" accounting before money is tossed at it. How about a comparison with the Brazilian sugarcane path for comparison? How does the Corn path stack up against Cane or the easy possibility of Sorghum?
In the S & SW what are the beneficial effects of an array of "superroof" shading? Compared to trees? How does photovoltaic compare with the French tracking mirrors & boiler approach?
Where are the accountants when we need them? And the engineering translators to make the comparisons understandable?

That next breakthrough is always "just around the corner". I remember reading in the 1970's that abundant and cheap energy from fusion was only 20-30 years away. Now I commonly read that it is 50 years away.

Solar energy promises have followed a similar non-linear forecast trajectory. Then there are the loons that claim big oil is "suppressing" development of these "earth friendly" energy resources. If they held promises I have no doubt that Exxon would be investing huge amounts of the record profits they have earned lately to dominate those markets.

Some people will say "You can't sell sunlight so the oil industry exec won't let it happen." You can sure sell solar technology. I just wouldn't hold my breath, or demand we stop using oil, hoping that cheap solar is "just around the corner".

"Lance", y'r right on. It really is easier to sell a 'conspiracy' than fallible good engineering. Just lookit the creos who peddle fluff. Some chap has an algal biota that will produce H2 in solar irradiated 'mats'. I'll not be hefting the experiment on my rooftop in the near future. I conceed that it 'may work' but someone's gotta design the input nutrient system AND the waste recycling process. Oh, yeah, the H2 collection. We need both the 'bean counters' and the 'imagineers'. Then some of us have to ask the questions about the effluent load and estimate the amperage requirement of the lift station. With a known gradient one can estimate a load and then ask what your photoelectric system has on reserve. "Oh, you don't have a storage of your input?" "What if we have to dump the first reciever at 0300 ?" The ol' nitty-gritti. Bean-counters can find the holes in Ge-Wizz schemes and someone can plug the holes! Have, er, faith!

I've just come back from the Industrial Physics Forum in Seattle, where there were several talks about solar cells. It's nice to hear about it in a scientific meeting, because, well, there's a little less hype. :) Nobody cited the magic "by 2015" number, for instance. They DID say that efficiencies achieved _in the lab_ are making great strides, and now that R&D is exploring other designs, materials and architectures beyond the basic silicon-cell varieties, they're making even greater strides. But they're no where near achieving 50% efficiency in a cheap, mass-produced commercial device. The consensus seemed to be that solar will be a growing part of our energy "portfolio" over the next few decades, but we will never be able to supply 100% of our energy that way.

My feeling? I'm not looking to solar to save the world from itself. But as it's used more and more, it can certainly help reduce our dependence on fossil fuels. Most of the IPF people agreed that diversity is the key to solving the energy problem. Not throwing everything but the kitchen sink at it, because priorities must be set, but developing a range of promising alternative energy sources and gradually reducing the percentage of energy derived from fossil fuels.

With $90/barrel oil the market will drive a move to alternatives as well as new technologies to extract petroleum, natural gas, and other carbon based fuels.

How do CSP (Concentrating Solar Power) designs stack
up against photovoltaics? There are European proposals
to use CSP fields in the Sahara & the Arabian peninsula
with HVDC lines to deliver CSP electricity
to Europe. This would benefit the producing countries
with desalinated water in addition to the obvious
cash for power.

Then there is the Solar Tower design being pursued in
Australia.

The obvious questions for all these are
1) how well can they scale up?
2) how do they prevent intermittency (i.e. how
well can they store energy)?

in addition to the usual cost/watt and environmental
questions.

They DID say that efficiencies achieved _in the lab_ are making great strides, and now that R&D is exploring other designs, materials and architectures beyond the basic silicon-cell varieties, they're making even greater strides. But they're no where near achieving 50% efficiency in a cheap, mass-produced commercial device.

Okay, that is interesting. Just out of curiosity, "cheap, mass-produced commercial devices" aside, did they mention what kinds of efficiencies they are seeing in the lab?

Also, just to be clear, what exactly is meant by "efficiency" in this context? Ratio of insolation to energy recovered per area unit?

What kind of "efficiency" do we get if we analyze, say, photosynthesis this way-- or in a more practical sense fields of ethanol-destined corn?

Thanks!

Neill B.
What in this hardboiled realm are "ovonics"?
We all pick up on hopeful theses occasionally that might have a bit o' utility. Pray, don't take it as derision if if I enquire about egg-layers as an energy resource! A diversity of propositions are entertained hereabouts so long as a bit of reverence for the principles of thermodynamics is entertained. Most posters here would like to have a chaw.

In Austin American-Statesman this AM.(22 Oct)
Austin's HelioVolt Corp has raised 109 Mil investment capital & is negotiating abatements to build a plant here. They will make thin film Copper/ Indium/ Gallium sulfide (CIGS) solar panels. Claims that panels can be made with a variety of substrates that are lighter & cheaper than conventional.

Skeptic8, your reply is cutely snarky but I was not trying to be funny. Ovonics is named after Stanford Ovshinsky, not eggs. His materials were once touted as the better solar cell - what about today?

See more at Wikipedia, which you know is the first place to look!

Cousin Neil B,
Pray accept my apologies. I had just returned from Uncommon Descent and the stink was still on me.

PV efficiency is a great thing to work towards! But I think there needs to be a bigger push to utilize the sun in any way possible. I have a number of posts on my blog about solar power and different ways they are working on to gain energy from the sun.
One of the novel ways is to put banks of clear tubes near power plants in which they put a small amount of algae. They set the tubes in the sunlight and pump the waste CO2 from the plant into tubes.
The algae gobbles up the CO2 and uses the sunlight to grow quickly. They harvest the algae and use it for fertilizer, dried to fire up power plant, with less emissions, and other things too.
I think we should follow up on traditional methods but also investigate any novel approach. Lot's of novel approaches in the past have turned out to be the norm as time went by.
Dave Br4iggs :~)