Thursday, March 15, 2012

Understanding Physics Is A Conservative Bias

It's astounding what you can learn on the Internet. Take this story, for example:
Scientists at Lawrence Berkeley National Laboratory announced Wednesday that they have been able to confirm a new high-efficiency solar cell design that utilizes nearly the entire solar spectrum.

Translation: They figured out a way to make solar panels generate electricity in the dark.

Scientists Develop Affordable Solar Panels That Work In The Dark
Now, I would think that anyone who stayed awake through his high school physics would know that there is something lost in that translation, but let me elaborate:

No, it doesn't mean that there are solar panels that work in the dark.

During the day, tremendous amounts of solar energy hit the surface of the Earth. It's something like a kilowatt (1000 watts) per square meter. If you're not used to the metric system, think of it as being the same as a square yard, because for the purposes of this discussion, it's close enough.

At night, however, almost no light energy hits the surface, even when there's a full moon and an aurora borealis (or an aurora australis). It's hard to turn solar energy into electricity when there's no solar energy. This, one would think, is rather obvious when one thinks about it.

Image credit: Lawrence Berkeley Laboratory

Of course, reading the Lawrence Berkeley Lab press release on the subject confirms that they are, indeed, merely talking about how it makes use of different kinds of semiconductors to collect light energy at several different wavelengths. So, yes, this is just about being better at converting solar energy during the day. Even the caption for this picture mentions that it converts sunlight, not moonbeams.

Yet, both this article and the one it was quoting got that wrong somehow. How they got all that wrong, I don't know, but scientific literacy being what it is these days, I'm not too terribly surprised.

Curious to see whether anyone else caught onto this, I read the comments. Someone did, indeed, catch the problem:
I don't see how using the full solar spectrum translates into generating electricity in the dark. To me, it only means getting more energy when the sun is shining. They do that by using all of the sunlight. Conventional solar cells can convert only a limited range of frequencies, and the rest of the sunlight is wasted--either reflected or absorbed or transmitted without converting it to electricity. They might use only the red light and ignore the rest. Or only infrared and not visible or ultraviolet light.

Scientists Develop Affordable Solar Panels That Work In The Dark: Comment by Cliff Lewis
Someone was paying attention in his physics class, apparently. Someone else commented that he agreed, so there are at least a few of us still out there.

Then I read this comment:
Well if this kind of story sets off your BS detector then maybe your BS detector needs to be re-calibrated.

The naysayers, that at the slightest provocation, jump to squash enthusiasm for development of alternative energies of all kinds are quite transparent. You are conservatives, or "independents" who want things to be just like they always were. OIL is king. Period. Even if it drives us into the dark ages. No other source can exist unless it's also enviro-adverse. Like Coal. Or Gas. It just kills you to think they we might actually pull off this "Energy out of thin air" pipe dream.

Sorry buddy. We're forging ahead and it's going to happen.

Scientists Develop Affordable Solar Panels That Work In The Dark: Comment by Ron Brunton
Not only am I a racist, because I think Barack Obama's doing a lousy job as President, but I am apparently a conservative, because I understand physics.

I learned that today, and I was reminded that not all stupid people are conservatives.

UPDATE (Mar. 15): Earlier today, someone from the LBL domain visited this article. So far, no correction that I've noticed either in comments or via e-mail. If someone familiar with the technology does have a correction I'm glad to hear about it, even if I end up looking stupid, too.

Actually, I'm told I'm rather good at that.

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