DARPA’s 42.8% Efficiency Solar Cells
August 2nd, 2007Do you get it yet?
Via: Treehugger:
Narrowly edging out the previous record set by Spectrolab late last year, two scientists at the University of Delaware have just created a new device that can convert 42.8% of the light striking it into electricity. The solar cell, built by Christina Honsberg and Allan Barnett, splits light into three components — high, medium and low energy light — and directs it to several different materials which can then extract electrons out of its photons.
One of the device’s key elements is an optical concentrator — a lens-type component that increases the cell’s efficiency by directing more sunlight to it than would happen naturally (a boost that contributed in great measure to its record-setting performance). It measures in at just below 1 cm thick, a major improvement over the Spectrolab model which featured a concentrating lens about 1 foot thick. Unlike most concentrators that use a two-axis tracking system to follow the sun, this optical concentrator is also stationary — a major feat.
The Defense Advanced Research Projects Agency (DARPA) — which has been funding this and similar efforts through its Very High Efficiency Solar Cell (VHESC) program — hopes to eventually incorporate this technology into portable solar cell battery chargers for American troops. It will now fund a newly formed DuPont-University of Delaware VHESC Consortium to shift production from a lab-scale model to a full-on manufacturing prototype model.
I’ll “get it” once somebody can explain to me how solar and wind will compensate for the lost fertility of agricultural soil for which fossil fuels for fertilizers, planting, harvesting, processing and transportation has so far been compensating.
Maybe you’ve missed the Kill Off category on Cryptogon:
https://cryptogon.com/?cat=38
Yes, lets give more “power” to the military. As if they need more to uh, well, to keep the crowds under control. What’s that Police song? – “when the world comes tumblin’ down, they’ll get the best that’s still around.” Yep, that’s DARPA for ya. Always looking out for U. Right.
Actually, these new power cells may go to good use. Read up on Gemany’s solar power subsidy program for farmers. They are making serious inroads to solar power common usage. This new tech. is a serious breakthrough.
Loveandlight: Have a look at How to Save the World DVD and the biodynamic farming method to see we don’t have to use toxic chemicals to supply the world’s food production needs. All the challenges are there to be solved if we put our minds & actions to it.
http://www.amazon.com/dp/B000MTOWXA?tag=cryptogoncom-20&camp=211493&creative=379989&linkCode=op1&creativeASIN=B000MTOWXA&adid=083MW6N8Z11BJB91ZR68&
and oh dumb me. I forgot, DARPA exists because of US tax payer dollars. If 100% of my salary is from tax payer dollars (as us fed i b), and about 50% of that goes to taxes, shouldn’t I get a “cut” off of the technology developed from my “investment” to utilize in my life? No. Its been the same with all gov’ment funded research for eternity. To the gov’ment go the rewards.
You’d figure the developers would get in on the action. But no, if its developed under the government dollar, not even Christina and Allan get a cut. Maybe a shitty bonus – or a nicely engraved plaque- but no patent thank you. That belongs to the DOD who is momma to DARPA.
Lesson 101 for researchers – don’t get a grant for research from the US government because you will lose all rights to your invention no matter how sweet or “powerful” it is. Resist the urge to suck at the government teat for funding, no matter how much you might believe u need it.
Better to put out an add in international newspapers for angels/investors where your research might benefit some patron in the world other than the us military.
Oh wait, my comments are SO UNPATRIOTIC! Sob. I guess I’ll be hearing all those clicking sounds again on my land line phones after I post this. I AM SUCH A FREAKIN TERRIST BY SPREADING KNOWLEDGE FROM THE BOWELS OF THE US COFISCATION OF KNOWLEDGE MACHINE.
Here’s the thing about solar, from a solar guy: it’s really ex$pensive, even with new technologies like this. Even the very best of desert thermal concetrators seek to reach grid-parity. That said, I’m pretty optimistic for the technologies coming out of silicon valley over the next 3-5 years. Ultimately, the really tough problem for most renewables is energy storage-here’s to ee-stor, which kevin is not so optimistic about.
jt–
Solar sure is expensive. If you’ve seriously thought about solar for your home, here’s the math–a post from another site (crooksandliars) and my reply:
Darrel @ 198:
Dilapidus @ 195:
Just because an option can’t be used in all circumstances or won’t solve the whole problem, it gets dismissed out of hand.
DAR
They certainly shouldn’t be dismissed but I think it is right to point out the common misconceptions people have of how much energy we can squeeze out of these alternatives relative to what we get out of cheap oil. An example:
I have a friend who purchased a 100 watt solar panel for about $400. That’s a very good deal. He has also spent about two thousand on a big bank of top quality marine batteries (certainly more than he needed for one panel). Also, he spent additional money on the controller and inverters etc. Now, how long would he have to put his solar panel in direct sunlight for it to generate the amount of energy contained in just ONE of the 21 million barrels of oil Americans burn every day? A barrel of oil contains the energy equivalent of 1,700 Kwh. A 100 watt solar panel has to have 10 hours of optimal sunlight in order to generate a single Kwh (value = about ten cents). So his panel needs to have 17,000 hours of perfect sunlight in order to generate the energy contained in one barrel of oil. And he needs to store this electricity in expensive batteries (and lose maybe 1/3 in the conversion). So, if he gets 200 days of excellent (10 hours a day) sunlight a year his panel will generate the energy a barrel contains, in 8.5 years. $400 investment, plus battery investment, plus babysitting (aim at the sun) and maintenance, plus lots of loss in conversion (the barrel has losses here too) just to get what we are used to getting from one barrel of oil sitting in the ground. Solar has it’s place but it is VERY expensive right now, dependent on a sunny sky, and has a lot more expense and limitation in the storage of the energy.
Darrel.
Thanks much, Darrel, for this clarity on solar. I’ve been considering getting a solar panel for an emergency back-up household power supply, and I’ve had two or three online conversations about this–shall we say, key–issue.
My interest here has been twofold: I’d like minimal power during outages, and I’d like to position myself to have at least minimal power if and when TSHTF re energy costs.
What, exactly, will I get for my buck?
If a 100-watt panel will provide a maximum of 1,000 watts (or 1 KWh) per day, clearly what I will get for my buck will be minimal indeed: I.e., I could run two 40-watt lightbulbs for ten hours.
The math got even more interesting when I looked at my last electric bill: I used an average of 31 KWh per DAY! It would take 31 100-watt solar panels to run my household at present levels of electrical usage–IF I got 10 hours of sunshine, all day, every day.
I think anyone who has seriously looked into solar has already made the very painful discovery that it is WAY too expensive.
Still, humans managed just fine for millenia without using even 1 KWh/day of electricity. We’ve largely forgotten the pre-industrial technologies that allowed our ancestors to be pretty comfortable without even 1 KWh/day. (Sadly, slavery was one of them.) The key things were growing and preserving your own food, root cellaring, and relying much more heavily on staples. There is little need to refrigerate the produce standing in the garden, and the milk keeps fine while it’s still in the cow, the eggs while still in the hen, and the meat while the meat-bearing creature is still alive. (There is a fascinating scene in “Mosquito Coastâ€, where Harrison Ford, as the inventor dad, asserts that what people need in the tropics is refrigeration. Even back then, I shouted at the TV screen: “NO! What they need is a COW!â€)
Our ancestors, only two generations ago, would have been ecstatic to have 1 KWh/day available–and they probably would have used it to pump water.
Managing comfortably past Peak Oil means reviving skills and knowledge that were still current when my grandparents were alive. But it will also mean re-settling people on the land. And the key element for prosperity–not to mention freedom–under such conditions is that the people must be freeholders in the land (own it), or, perhaps better, that land be held in common by communities.
I don’t think we should be trying to find the magic bullet that will keep us watching TV and driving 50 miles a day for the privilege of working in a cubicle, and then driving a lot of additional miles to buy bad food. WE SHOULD BE FOCUSING ON RE-ORGANIZING SOCIETY. And there is no reason why this reorganization could not allow for a small degree of electrical/fossil fuel usage.
People should be demanding land for the creation of largely self-sufficient communities, and people may actually do this at some point–but not until our present lifestyle has become untenable for almost everyone.
For the most part, I’m with crazylove, back on post #37: A pre-industrial lifestyle sounds to me like HEAVEN–all except for the water and water-pumping issues, that is.
“Clean energy is expensive,” is a sad straw man argument at this point.
https://cryptogon.com/?p=252
https://cryptogon.com/?p=501
Wake up, people.
I’m sure the elites see it as their duty, as the people who run the planet, to engineer a reduction in the population, there’s a kind of cold logic to it. But there is also the fact that they make a lot of their money via the oil business one way or another and from funding wars so there appears to be competing motivations.
I also think at a time like this there will be disagreement amongst them about how to handle the situation but whatever happens you can trust that they will be turning a profit along the way. Just don’t confuse the fact that they are making money off something with their long term goals – which no doubt is an efficiently orgainsed planet organised to serve them.
Ultimately though Kevin’s thesis that if they were worried about energy for the masses they wouldn’t be wasting money in Iraq is spot on – there’s just a lot of other stuff muddying the waters.
As for me, I’ll be getting solar panels. They’re not environmentally in the slightest, but they will give me independance from the hideous power companies in NZ and it should save me money in the long run (based on the assumption that a solar panel will last 40 years). The only criticism of Sharon’s calcs above is that people are careful not to waste electricity when it comes from their own battery supply and conserve it extremely well.
Holy crap, Sharon, you use 31 Kwh at your house? Would you adopt me? That’s a lot. You live well.
Yes, solar is still not cost effective, but it, along with other renewables become more cost effective when you calculate the total opportunity costs now and in the future.
I can’t believe I am arguing this point. Until the NeoCons came along, I was a proud conservative member of the Republican party.
Maybe you can teach an old dog new tricks.
By the way, I am also an electrical engineer. Renewables are really becoming viable, thanks to new tech.
Jim Burke–
Maybe my energy use high–though I didn’t think it was unusual. I have two grown daughters, one teenage daughter, and a granddaughter living here, besides myself.
I have tried to train everyone to turn off lights and TVs when they’re not in use, but it seems jack boots don’t come in my size.
The electric bill that came in yesterday’s mail shows that I used 50 KWh/day last month. That’s because we were running the A/C.
Could I cut back on my electrical usage? I’ll bet if I lived here alone, I would use less than 10 KWh/day–probably far less, since I never watch TV and don’t leave lights burning. And, while we were in the midst of extensive plumbing repairs, I discovered that the hot water heater alone costs about $20/month–or approximately 200 KWh/month, or around 6-7 KWh/day–about 1/5 of our total electrical usage.
If I had only one or two people living here, I could turn off the hot water heater when it was not in use.
You’re making me defensive here, so I’d like to mention that I don’t use central heat. Instead, I have two propane fireplaces and one propane wall heater.
One of the propane fireplaces is in the living room. In winter, I heat only that one room. If someone wants to take a shower, they turn on the wall heater–and turn it off when they’re done. The bedrooms are basically unheated. I also have a wood stove. It used to be the only heat we had, but I now use it basically for supplemental heat.
One of my neighbors suggested I go with propane fireplaces/wall heaters, because they are 100% efficient (you aren’t heating ductwork, attics, and crawl spaces), and because you need only heat the rooms you are actually using.
I’m still debating going with solar, and I do feel that some kind of back-up system is better than none at all, but the figures I quoted in the above comment are very sobering. The estimate given in the original post–that one KWh, from the grid, costs about 10 cents–is almost exactly what I’m paying per KWh.
In a year, the cash value of the 1 KWh I could generate per day from a 100-watt solar panel would be $36.50. Or, $365 in ten years, or $1,460 in 40 years (the life of the panel).
Other costs–besides at least $400 for the panel, include one or two marine batteries at $50 each, a converter, which I think is $50-$60 at Wal-Mart, and a charge controller for about the same. Figure a total cost of $600+ to generate a maximum of one KWh/day. The set-up would pay for itself in 20 years–maybe sooner, since electricity will probably go up–a lot. And, of course,
in the event of collapse, such a set-up could be invaluable.
Oops! I meant “inverter.” You could skip the inverter if you bought electrical stuff that ran on DC–but that would also cost a bundle.
Sharon, the real question for an individual is how much money do you pay the electricity company? Over here the average monthy bill is $150 or 150 per month. A full solar setup might cost about $23,000 (here) which would mean it had paid for itself in 13 years.
Whether this is too long a time period or not depends on whether you are going to stay in the house for ever or not and whether the system will last that long. I’ve been told a panel will last 40 years. The solar hot water, probably as long The rest of the gear I don’t know about.
please excuse the typo. It’s supposed to just read …monthly bill is $150 per month.
Kevin, in regards to your comment (number 9), you are saying that “clean energy” is not expensive?
I think there are two different types of expensive, your links show that it’s not expensive in terms of government budget. However I believe it’s still expensive in terms of an individuals budget, and unfortunately, the government is not really controlled by the people.
I don’t see solar becoming common, until it is within the realm of individuals budgets, or the government starts being directed to do the will of the people, but I’m not holding any bets as to what will happen first 😉
Aaron, sorry, I lost track of this thread for awhile.
To reply to your question/comment:
A 100 watt solar panel would optimally generate 1 KWh per day. That’s optimal–meaning it collected 10 hours per day of direct sunlight. One KWh costs ten cents from the electric company. (My electric bill ranges from about $80/month to $120/month–the latter when I’m using A/C during the hottest part of the summer.)
My cost to generate 1 KWh/day (optimum) would be probably over $600. By paying $600 today for such a setup, I would generate $36.50 worth of electricity over a year’s time, $365 worth of electricity over ten years time, $730 worth over 20 years time, and $1,460 worth over 40 years time.
You say that your solar setup would pay for itself in 13 years time. How many KWh do you use per month? (I am seeing that your electricity must cost more than mine. How much do you pay per KWh? Is it more than ten cents?)
As you can see from my above math, my solar setup would pay for itself in a little less than 20 years–IF I COULD DEPENDABLY COLLECT 10 HOURS DIRECT SUNLIGHT EACH AND EVERY DAY–and IF LOST ENERGY THROUGH CONVERSION TO ELECTRICITY AND THEN TO AC WERE VERY MINIMAL.
Now, I haven’t examined these efficiency aspects at all, but I’m guessing that I would get 10 hours per day of direct sunlight only about half the time–maybe two-thirds of the time. If I could generate 1 KWh only every two days, it would take closer to 40 years for my setup to pay for itself. Which is to say, that, at the end of the 40-year life of the panel, I would have come out a little bit ahead. Big up-front cost; little savings. Maybe no savings, even at the end of 40 years. I should mention that it is highly unlikely that I will still be around in 40 years.
So: No economic advantage–AT THE PRESENT COST FOR ELECTRICITY. Other possible advantages: Electricity will for sure go up in price; I would have an emergency back-up system; adding to the system over a period of years would ultimately allow me to be “off the grid.”
This last is highly desirable for a number of reasons–perhaps the most compelling of which is that the cost of electricity will probably increase exponentially, and it will almost certainly do so in less than ten years.
Hence, I could very well find that my 100-watt panel, marine batteries, inverter, and charge-cotroller had paid for themselves in less than ten years. Maybe a lot less. You could find that yours paid for itself in a lot less than 13 years.
But we are guessing here.
If I do choose to go with a minimal solar setup, it will be because I’m guessing–betting good money, really–that the cost of electricity will be very, very high in years to come.
Have you checked the wattage requirements of varios appliances? Start checking this out, when you’re out shopping. A 100-watt solar panel setup would allow me to run a one-burner hot-plate for a couple of hours a day, for example. I also saw a tiny refrigerator–dorm room frig–that pulled only 65 watts. That means you could run it for 15 hours/day with a 100-watt panel setup (on a nice day). I guess you could move it onto the porch during the winter and use your 1000 watts for something else. It’s good to see what you can actually run on 1 KWh, and plan accordingly.
Am I going to stay in my house forever? It’s Shady Pines for me in 20 years, should I be fortunate enough to remain continent that long.