Future Pundit has an interesting post on the Large Solar Electric Thermal plant near Granada (Andasol) Spain (picture from Sci Am) which can generate electricity at night.
"In a market that 182 million kwh might sell for, say, 10 cents per kwh. It would probably sell for less in the US where the average retail cost of electricity is about 11 cents per kwh. But let us assume a higher price in Europe. Okay, that would still only amount to $18.2 million per year. Seems like a small return on a few hundred million [$380 million] dollar investment plus operating costs and maintenance costs. But if this electricity is sold during peak hours maybe it sells for more than 10 cents per kwh? Does a political deal assure a higher price? If so, how much higher?
Let us consider the avoided CO2 emissions. If the 172,000 tons of avoided emissions were taxed at $30 per ton (which is one figure I've heard proposed for how much carbon emissions should be taxed) then the amount of avoided carbon taxes would be only $5.2 million per year. That doesn't improve profitability very much."
While expensive now, this seems to have a couple things going for it, its use of readily available technologies and materials and limited storage. However, it is ugly, expensive, and would seemingly require lots of desert land.