Seven cents per kilowatt-hour, that is. That's about the standard price for electricity in the United States (some locales will vary; California averages about 10 cents per kilowatt-hour). Renewable power needs to be price competitive with 7 cent non-renewable sources. Tidal can be, and wind is close, but both have location requirements (and wind needs lots of space). Solar, however, is still generally priced out of competition, in the 30-45 cents per kilowatt-hour range. But nanotechnology may well change that. Investor's Business Daily profiles three companies working on applying nanomaterial and nanoengineering discoveries to the more efficient generation of solar electricity: Nanosolar (making solar cells 100x thinner than current ones), Nanosys (making specialized materials for embedding into construction material), and Konarka Technologies (making light-activated plastic).
Favorite line of the article: In time, such work could become "world changing," said Josh Wolfe, a managing partner of nanotech-focused investment firm Lux Capital.
Yes, the price of solar has to come down (although it is already pretty good as far as heat pumps (geo-thermal) are concerned), but the price of other sources also has to go up to represent the REAL costs.
f.ex. Coal doesn't really cost that little if you take into account all the other costs that it externalizes (air quality, mercury, greenhouse gases, lung problems, etc).
Solar and wind have higher prices per KW/h, but their whole costs are showed in these prices. You pay for that and you're done.