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DARPA Awards $53 Million for Solar Power Research
mygadgetbox writes "Defense Advanced Research Projects Agency (DARPA) will be giving a consortium led by the University of Delaware nearly $53 million in funding to more than double the efficiency of terrestrial solar cells within the next 50 months. DARPA wants the consortium to develop and produce 1,000 Very High Efficiency Solar Cell (VHESC) prototypes that are affordable and that operate at efficiencies of at least 50 percent. The goal is to create solar cells that operate at about 54 percent efficiency in the laboratory and 50 percent in production."
We spent two decades wasting time trying to improve the energy efficiency of solar cells. The energy efficiency isn't what matters - it is the cost efficiency! If you are using solar cells as supplemental power to a house (their most effective application), then doubling the energy efficiency of the panel just means you get to use a smaller panel. Who cares - you have a whole roof's worth of space up there. Whereas if you get the price down, then you will decrease the amount of time it takes to pay off the cost of the cells, making it worthwhile to include them in more homes. And for other uses - cars, power plants, even if we had 50% efficient cells they still wouldn't generate enough power to be much use.
I have been getting excited about some of the recent research that is making progress towards less costly, cleaner (to produce and dispose) solar cells. I guess if you are the military, and price is not an issue than this DARPA research is usefull. They need to find some way to power all this new electronics equipment that soldiers are carrying. But it is improvements in cost efficiency that will really make a difference in real world.
...than looking for ways to bury waste products in the ocean.
Photocells are already fantastic technology. Not only do you save the energy you would otherwise be drawing from a power plant, you also save the energy needed to deliver the energy to the point where it is used.
A lot of public lighting near my home is now solar powered. The big advantage is that you don't have to dig trenches to the site. Trenching is very expensive because of the associated labour costs, and labour costs feed back directly into energy costs.
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Most of what Parent says is true- for the applications in question (home use, vehicle use, consumer use in general) the cost of solar cells is the limiting factor. However, this is DARPA we're talking about here- as well as a bunch of commercial clients. The applications mentioned in the article (primarily the military) rely heavily upon efficiency and not so heavily upon cost efficiency. Yes, it would be nice if GI Joe's GPS solar cell only cost fifty cents, but if it weighs a hundred pounds? I'd rather have a five-hundred dollar solar cell producing enough in half a pound. Efficiency is important in some areas, cost effectiveness in others. Research into efficiency isn't a total waste.
I used to carry a bottle of whiskey for snake bite. And two snakes. -Nefarious Wheel
But the article is almost talking as if the goal of doubling the now 25% efficency being doubled are being guaranteed to be met which is hardly the case - it's been over 30 years (where it was what 8% effieciency?) since solar cells were introduced and many other countrie/companies have been working on improving efficiency without that huge jump in performance - Germany/France in particular.
Be Afraid, Be Very Afraid I really encourage you to read the whole post.
~CK
Halliburton now owns the sun.
Never shake hands with a man you meet in a fertility clinic.
This was not their original plan at the outset. --Basically, they bought a property, and cleared a lot far back from the road. Then they learned that to have AC lines brought to their house from the mains, the local power company would charge them over $10,000 for the job of sinking four poles and running cable.
They thought, "Wow. Ten grand? Sheesh. What other options are there?"
The result was some research and a re-jigged construction plan using alternative energy. They spent about the same amount of money installing Geo-thermal and solar panel solutions.
10 big cells cost them about $8000 CAD. The rest of the money was spent digging trenches and laying thermal transfer pipes, air ducts and house wiring. Now they have all the power they need.
Strategic spot lighting using 12 volt halogen bulbs rather than bathing entire rooms in light minimizes the impact on energy reserves. Laptops are used instead of desktop computers, and various other appliances, like radios and televisions are run with DC to AC converters. Water is pumped from a well to a reservoir at the top of the house which provides pressure. Even while feeding the needs of an active family of four, the array of 5 big chemical batteries which stores electricity from sunlight never dipped below a 95% full charge on any of the days I visited. (The power readings were set on a cool display for all to look at.) --And the house is also absolutely enormous; 5 bedrooms, plus various huge family rooms the size of small churches, etc. A total mansion, and after the initial investment, it costs exactly zero to light and power.
Cooking is done on a big gas range fed from a pair of large propane tanks which contain enough propane to last more than a year. Water is drawn from a well. Refrigeration was the only puzzle still to be worked out, and while pondering it, the family had spent two years eating fresh foods while keeping milk and other such items in a basic camping cooler in the kitchen. Half the things people normally keep in their fridges don't really need to be there; milk and beef doesn't go bad all that quickly, eggs don't need to be refrigerated at all, and chicken and fish are simply bought fresh the day they are intended for consumption. --After realizing that this worked without any problems, the family basically concluded that they didn't really need a fridge in the first place. --Though, they told me that they had found a super-efficient 12 volt DC fridge on the market for homes exactly like theirs, but that they didn't think they really needed it.
Half the problem is not the power source, but the notion that we need so much electricity in the first place. --If we change the parameters of the problem, we can start using different solutions which have already been accepted by industry. Simple.
Despite the opposition, alternative energy is here for anybody who wants it.
-FL
The article discusses that the goal is to improve the efficiency of solar cells to 50%. As I mention earlier in this thread, silicon-based semiconductor photovoltaics top out at a theoretical efficiency of about 25-26%. Other semiconductor technologies top out somewhere around 35%. These are the two technologies people think about when they imagine solar cells. I think the outlook for discovering and commercializing a semiconductor-based solar cell that's 50% efficient in the next 50 months to be very poor. I won't get into the physics, but the theoretical limitations have to do with the fact that semiconductor photovoltaics make inefficient use of the solar spectrum: a red photon will produce as much electrical energy as a blue photon, even though the blue photon is more energetic.
/. lately). Instead of trying to burn a ship, the focused sunlight heated sodium to about 1200 Celcius, which liquified it. That sodium was passed through a heat exchanger to boil water, which made steam, which turned a turbine, in a similar closed-cycle technology to a nuclear plant.
But solar power is not limited merely to what one can do with photovoltaics. When people talk about the many terawatts of solar power that falls on the surface of the earth, most of that solar goes into two things: photochemistry (like in plants) or to heating the earth's surface. Plants make very efficient use of the solar power that falls on them, and a black, nonreflective object will convert the incident solar power to heat (or reradiated infrared light) with extremely high efficiency. If we could focus efforts to developing technologies that capture sunlight first into chemistry or raw heat and converting that to electricity, rather than the direct conversion to electricity that photovoltaics do, we may have a better chance of reaching the 50% goal.
For instance, there was (is?) a solar power project that in the California desert that was a solar-thermal generator. Hundreds of mirrors focused sunlight onto a tower, much like the Archimedes death ray (which has received some press in
I'll admit this isn't much use in the battlefield, which is what DARPA is aiming for, but it is not out of the question to consider a smaller solar thermal unit for an encampment, which used a different medium than sodium.