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40% Efficiency Solar Cells Developed
gtada writes "A story published at Physorg.com discusses recently published research into the fabrication of solar cells that surpass the 40% efficiency milestone. Such devices would be the high water-mark to date, and hint at the possibility of even more effective technology. 'In the design, multijunction cells divide the broad solar spectrum into three smaller sections by using three subcell band gaps. Each of the subcells can capture a different wavelength range of light, enabling each subcell to efficiently convert that light into electricity. With their conversion efficiency measured at 40.7%, the metamorphic multijunction concentrator cells surpass the theoretical limit of 37% of single-junction cells at 1000 suns, due to their multijunction structure.'"
That's exactly what I was going to say. I believe that most solar cell manufacturing processes would scale well, so they could be made cheaply if there was enough demand to justify scaling production up. Where could that demand come from? What if the Federal Government mandated that all Federal buildings had to be solar powered? The rest of us would reap the benefits of economy of scale. Now, if we could only figure out some way for the oil companies to reap massive profits from such a scheme, I'm sure it would happen in no time.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Yes, and we have the nuclear waste for oh, I don't know, a few HUNDRED THOUSAND years ...
Only with stupid old technology. The Integral Fast Reactor generates 100 times less waste and it's only hotter than ore for a few hundred years. We should be building one at Yucca Mountain as a national security priority.
Fusion will be great in 40+ years, but that's a little late to act. We could have one of these running in probably 5 years.
Solar, at 40% efficiency would still require covering something like 8% of the land surface area of Earth to meet current-day demands. Wind is too variable, hydro is too small - we basically have coal and nuclear as the two viable baseload options.
Obviously, TBPB don't want to end anthropogenic global warming. It's left as an exercise to the reader to speculate on why.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
All the more reason we need to establish reliable mining on the moon. Concentrations on the moon are about 80% higher than on Earth. You know, there is a lot of history ahead of us and maybe Lunar mining would allow future infrastructure that at this point in time boggles the imagination.
Shh.
I think cost is still the limiting factor right now.
Yeah, there's a guy in NJ who went completely solar for his energy needs and spent about $400K on the system, not counting maintanence costs.
If only Moore's Law applied we'd all have a setup like that in ten years.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
What isn't being trapped by jumping electrons (that other 60%) is going to go into heat - what we need is a heat engine on the back side of the cell recovering that other 60% ...
"And how much CO2 do we emit when we mine coal? "
Sigh. Everytime I criticise nuclear power someone brings up the strawman of coal power. Next time, I must remember to address it first.
Yes, coal is terrible. Yes, we should stop burning it. Yes, nuclear is probably better than coal.
BUT, renewables are better again. If we're going to change our infrastructure, why settle for second-best? Why not change to wind, solar and tidal, and have the best power source (and maybe use nuclear a _little_ bit, where necessary to ensure supply).
Now, I read your other post. I'm no expert, but my understanding is that, in general, the nuclear industry is hugely subsidised by the government, and that's the _only_ way that nukes are at all cost-comparable with coal. In most countries, nuclear disasters are uninsurable, which means that the government is effectively underwriting the nuclear industry even more.
In any case, _even_ if there is plenty of fissile material available, we _still_ have to mine, process and dispose of it. for fusion power, I agree - we have plenty of fuel. Fusion power sounds great, unfortunately it doesn't work yet.
no the main material is silicon and it's plentiful, the expenive part is the production, it requires a LOT of processing and quality control. people keep rambling on about moore's "law" but fail to realise the price of a cpu hasn't really fell very much at all in 10 years, they've just gotten faster (which is all moores prediction is to do with). in the case of solar panels this will NOT help them sell. they need to get much much cheaper for adoption to happen.
If you mod me down, I will become more powerful than you can imagine....
If you are talking about the Hopewell Project Solar-Hyrdrogen residence, that actually uses solar energy it does not need to produce hydrogen to store energy. It actually cost $500,000 to build it, house and all, using off the shelf parts. It does run completely off the grid. Their goal is to bring a turnkey system to market for the cost of a midrange car by 2008.
True, but it makes me wonder how they'd hold up to the softball sized hail that regularly crops up in colorado.
I also remain curious about the weight- roofs seem to be supported by thinner and fewer A frames and you can see in many roofs where they sag rather obviously on either side of a beam. Will roofs have to be made stronger to support these heavy glass panels? I thought many of the recent ones were thinner and made with plastics? I saw one on TV the other day that was made to look like that sheet stuff that has thin shake-like things on it- even had nails through it for holding it up.
You will do anything to run just coal and gas. That is, until you can figure out a way to own the sun. At that time, you will then own up to loving solar.
If you shop surplus you can make a 60 watt solar panel that will not only run a laptop but charge it's batteries as well.
I had one for a old outdated dell D600 laptop for the local ham radio group's Search and rescue group. we built it from $40.00 of surplus Yacht flexible solar cells. (3 units that were 3 feet long and 1 foot wide) they made 14.5 volts that simply powered a dell car charger/power supply for that laptop. It worked great just laying them out on a picnic table aiming straight up.
Hard part is finding Marina auctions that have big boats and foreclosures where people had solar on their boats they could not afford. I live in a area where that happens a lot.
Do not look at laser with remaining good eye.
Take a thousand heliostats concentrated on a turbines boiler or the hot side of a sterling engine and you get decent efficiency numbers on the comparative cheap. A technology that has been, and is being done now rather than futuristic laboratory musings which I must say, makes rather tiresome reads over the course of decades. Yes, it is interesting science and important work to boot but we are living in the here and now. I would be more interested in scaling practical applications of energy alternatives today rather than this seemingly endless stream of announcements concerning potential breakthrough technologies always found five, ten or fifteen years out if ever. In the meanwhile we do essentially little if nothing, neither of which scales very well.
Of course there is the matter of economics which is important and from that perspective the hands down answer is nuke plants even though many dismiss such an energy source as contemptible, it is the most practical solution near term but like a deer caught in the headlights of an oncoming car, we are not moving in that direction either even though we have copious amounts of high purity nuclear fuel stored in our aging arsenals. As if it is better to threaten the world with it over access to oil than it is to burn it up in reactors.
The dilemma of course is that per capita energy consumption is on the rise worldwide, in fact we are fostering such in places where people are not already bound to the gas pump and electrical grid as though we are doing them a favor. One laptop per child indeed. In the absence of any real economical breakthrough in practical energy technology near term, a harsher reality will take center stage. That being the reduction of per capita energy consumption without any technological breakthroughs leaving energy dependent societies in a perilous position OR reducing the per capita side of the equation. People.
Depopulating humankind by fifty percent will have a positive effect on our energy consumption and if we continue to effectively do nothing that will happen via disease, starvation or war. I wouldn't count on the mass euthanasia option given the current state of even our most civil societies even though it is an option and one perhaps we should seriously start to think about. Of course as the energy situation becomes increasingly grim, such an option might become a preferable elective especially for those formerly accustomed to living more comfortable lives.
If we stay true to our current course, the most likely outcome will be global war between those with the military might to stake claims against earths resources for empirical consumption and those attempting to retain preexisting ownership or control. In fact, it seems that has already started and is escalating. That said, I don't expect war to be the final solution for even nations found abundant in military resources will quickly deplete them. What remains from that point forward is simply a blood fight to the knife as modern society collapses worldwide.
With the failure of transportation and technical infrastructure comes widespread panic, starvation and disease eliminating high density human populations. The number of survivors we can only guess at. As to the percentage of current population that might survive and sustain beyond such calamity initially, I would suggest single digits. Ironically, the people most likely to survive are those who currently have the least.
As disturbing as this scenario is, it is not yet to late. It is imperative that we start making better decisions however and earnestly acting upon them with all due diligence if such a future is to be avoided. Not within the next fifteen years, ten or even five. Now.
A lot of the high ($400K) price tag was for hydrogen storage and use in a fuel cell. The sola power portion was much less than this.s -selling-solar.html
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