Baumblog EST 1968 - A blog for the Baumbachs who originated in Syracuse, NY

Researchers at Ohio State University have made a startling discovery with solar cell efficiency. Before I get into the specifics of this research, let me give you a few facts regarding why solar power hasn't had much of an impact on our energy problems to date:

It comes down to poor efficiency: solar cells absorb very little light in terms of the total wavelength of light (remember that colors are shifts in the wavelength of light, and there are wavelengths that are not visible to humans, too). They also work by having this light jettison a free electron from the substrate material--that's how we generate electricity. However, that electron is only free for a few zillionths of a second, making it hard to capture it (charge separation). The combination of these two issues meant the net efficiency by the late 80s was only 17%...today, some high end cells manufactured for NASA can hit up to 30%, but they're super expensive. Fossil fuels, as a comparison, are 98%. These are also not that cheap to produce, and take a lot of surface area to produce any amount of measurable power. What's the use of solar cells to power your house if you need a solar array the size of your properly to power 50% of your needs?

So, what did these researchers come up with? A new combination of material that now absorbs the full wavelength of light. That's pretty cool--a lot of energy was lost in the wavelengths the old materials would miss. Even better, however, they managed to drop the cost of charge separation, as this material now emits two forms of free electrons and one of them stays ejected in the microsecond range--while that sounds super fast, it's several orders of magnitude in time longer than normal free electrons from the original solar cell design. See this article for some more technical detail, if you'd like it. If that's too high-level for you, try the abstract for the paper instead. :) Just kidding, here's another less-technical summary.

So, what does this do in terms of efficiency? Word is, this approach could bring us right on the doorstep of fossil fuels, and do it in a much smaller footprint. You could conceivably power your house's needs from a few panels on the roof of your house, and it could power ALL your needs. That would be awesome, wouldn't it?

Practical application is years away obviously, and right now we don't know if they'll come up with a cost-effective manufacturing method, which of course is critical for deployment and competition with existing power sources. But hey, this is the first really big news in solar cells since the early 90s, when they managed to up the efficiency to 20% using gallium-arsenide (this eventually tapped out to the 30% they have today). Exciting stuff, indeed!

Steve said about 10 hours later

Can you say hello to electric cars? Free solar power, to charge your car. Question is, how big of a capacitor is out there to hold the charge from the daylight to recharge your car and run your power at night? I assume there's stuff out there, I just don't know crap about electrical stuff.
Marc said about 12 hours later

Sounds too good to be true, so it probably is. :) If not, Ohio State University just became the most important university in the world.
GJ said about 24 hours later

That capacitor you speak of is the modern day fuel cell, Steve. But yes, electric cars would be just one of the major changes to our lives, should this come to fruition.

Marc--you are absolutely right to be skeptical. This sounds a lot like the "free energy" argument that the perpetual motion folks often claim. In this case, we have a peer-reviewed article, and you can bet your life that it will be tested to death, being re-evaluated by scientists the world over. It may not survive this inquest, especially if these scientists are fudging their numbers. Just look at what happened to the boneheads who tried to prove cold fusion.

I'm inclined to think they may be on to something, though. It's been known since solar cells were first designed that the limitation of frequencies of light and the charge separation cost were the two huge limiting factors that required gigantic arrays to produce measurable power. Certainly, work has been done to expand the frequency pickup--most of the more advanced cells out there today do this, and this allows them to almost double that 17% efficiency rating. Those methods are very expensive and probably won't ever find their way into the public's hands.

This setup picks up all the wavelengths of light--which we knew was coming someday, but never figured it'd be this easy. On top of that, they discovered a new form of free electron that makes the capture of said electrons far, far easier. That wasn't something anyone expected, and it's cool as hell. If they can scale this up without losing that property, we are in for a wild ride. Of course--that's still an IF.

Even if this doesn't pan out, all is not lost. The scientific principles here, some of which have already been vetted, will find their way into other new solar cell designs. Progress moves on, and other advances will occur--and probably quickly, since this has opened up a lot of new thinking in solar cell design. It may well be 20 years before we see commercial applications, but hey, it's a great light at the end of the tunnel.
GJ said 1 day later

Steve--an update. Solar power cars--not going to happen. Even if we increase the efficiency five-fold as promised here, you still won't have enough surface area on the car to generate enough power even in broad daylight. You could, of course, plug your electric car into your solar-powered house to charge it, but in this way it wouldn't matter if your house had solar or not.

Another issue--more to Marc's point. Manufacturing efficiency is still a big issue. One would hope that demand provided by the above solution would serve to light a fire under the manufacturing research folks, as without a breakthrough there, solar will never have enough units on the ground to rival fossil fuels.
Geoff said 1 day later

forget solar...what about an antimatter car? Now that would rock. Had an enjoyable TV show on Discovery called Apocalypse|How which talked about it. Amusing to say the least. Of course right now we have about enough antimatter to power a light bulb for a few minutes according to Wiki, but with a few grams of it we could send a ship to Mars in a couple minutes.

GJ said 1 day later

You missed this quote: "If we could assemble all of the antimatter we've ever made at CERN and annihilate it with matter, we would have enough energy to light a single electric light bulb for a few minutes."

And then there is the cost equation. :)
Geoff said 1 day later

yeah that was funny too. However, if we could manage to convince some nanobots to build us some antimatter, we could take an afternoon trip to Alpha Centauri!

Geoff said about 15 hours later

Pretty darn close to Ashlyn! She was 6lbs, 12oz as well. Came in about an hour later a little after 8pm. She was a bit longer though i think. Congrats to Gina and Eric! We expect some pictures soon!

Steve said about 22 hours later

I'm going to try to stop by and see the new baby this weekend, if they are home, and will take pics! Congrats as well Eric, Gina, Kyle, and Katie!

Marc said 1 day later

Congrats Eric, Gina, Kyle, and Katie, I look forward to the pictures as well!

Geoff said 11 minutes later

I can't imagine...Spaceship earth was intense...and that peaked at 2.5Gs. 5 or 6G's would be bone crushing hahaha

GJ said about 4 hours later

Shut it off when they reached for the barf bags. :)