They are planning to sell this to utility scale installations; mainly in the dessert, where it makes sense. They are getting 43.5% efficiency, and the thing can work with concentrators from 400 to 1000 suns. That means, they can concentrate 1 sq foot, roughly, of sunlight with a lens onto a solar cell one centimeter square. The sun puts about 100 Watts of power on the surface of the Earth at any given moment; again rough average assuming no cloud cover. Doing the math here, that means we can get 43.5 Watt hours of power for every foot of lens we have using only a centimeter of silicon. Total USA energy usage, that's oil, coal, nuke, etc, is 29 x 10^15 watt hours a year.
Assuming that we could get 6 hours a day with these solar cells on average every day in some place like part of the Arizona - New Mexico deserts, how much land would we need to power the USA; assuming we could store this power to use it when we wanted. That's another problem, but let's avoid that for now.
Our 1 sq ft gets us 261 W-h of power a day on average assuming that 6 hours a day, or 95MW-h a year. I know that sounds like a lot, but a standard 1,000 MW base load power plant does 6.5 times that in a month; 648,000 MW-h in an average 30-day month; most of those plants are running 90% of the 24 hours in a day. Anyway, back to our numbers. 29 x 10^15 divided by 95 x 10^6 equals 305 million or so square feet. Now that's just for the concentrator, realistically, we'll need probably 2x that amount of space to build a real solar facility. But, how big is 305 million square feet. 1 square mile is just under 28 million square feet, so if we double the 305 million we need, and divide that by our 28 million, we get 21 square miles. That's not too bad an area to cover a desert with to get all the power the USA used with in the last year. now all we need to do is to figure out a way to store it, converting that to gas/diesal/hydrogen and or transmission losses would probably mean we'd need to double this area again, but still even doubling plus a bit more to 50 square miles is still not that much. That's 10 miles by 5 miles. 43,480 square miles of the lower 48 of the USA is already built-up with roads, houses, etc, so 50 or even 100 or even 200 more is not a lot.
43,480 square miles of the USA is already built up with roads, building, etc(http://earthobservatory.nasa.gov/Newsroom/view.php?id=24956
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