Closing in on the Solar Singularity

By | December 21, 2009

The near future may be nuclear powered, or it may be thermonuclear powered, or it may be powered by geothermal energy or algae-derived biofuels or wind power or tide power or (most likely) some interesting combination of all these, plus the big one, plus some additional sources of energy thrown in for good measure. The big one of course is solar power. The sun is out there, blasting our planet every day with far more energy than we could need or (right now) even think about using.

Ray Kurzweil says that our current level of solar power use is bout eight doublings away from being great enough to power our entire civilization. will we achieve those doublings?

If we do, it will be because of developments like this:

Hot Electrons Could Double Solar Power

For decades researchers have investigated a theoretical means to double the power output of solar cells–by making use of so-called “hot electrons.” Now researchers at Boston College have provided new experimental evidence that the theory will work. They built solar cells that get a power boost from high-energy photons. This boost, the researchers say, is the result of extracting hot electrons.

The results are a step toward solar cells that break conventional efficiency limits. Because of the way ordinary solar cells work, they can, in theory, convert at most about 35 percent of the energy in sunlight into electricity, wasting the rest as heat. Making use of hot electrons could result in efficiencies as high as 67 percent, says Matthew Beard, a senior scientist at the National Renewable Energy Laboratory in Golden, CO, who was not involved in the current work. Doubling the efficiency of solar cells could cut the cost of solar power in half.

1. Figure out a way to get power from the sun.

2. Improve that process by driving the price down and the efficiency up

3. Repeat.

Hey, it worked for computer chips.

  • Stephen Gordon

    Phil: there’s are two different doublings in play in this post. The doubling of the amount of power produced by solar (which is what Kurzweil is talking about) and doublings in efficiency (which is what the hot electrons development could do). One doubling in efficiency could easily lead to 8 doublings in the amount of power we get from solar by breaking through the grid-price barrier.

    A very exciting possibility!