Solar Updraft Tower
As the turbines spin, clean renewable energy will flow into the power grid.
In short, it's an interesting mix of the best of both solar and wind power; but unlike solar and wind, the mechanical energy created by Davey’s machine allows the unit to operate 24/7.
As for cost, the project has a $750 million price tag. According to a 2005 industry report, this would imply about 10 cents per kilowatt-hour, which is roughly one-third the cost of electricity from current solar cells and almost half of the cost from nuclear power.
Financial models suggest the tower will pay for itself in 11 years; engineers believe the tower will have a life span of 80 years.
Once it’s built, Davey’s tower can be expected to produce power with virtually no maintenance. Better yet, it requires no "feed stock" — nothing but air and sunlight spin the turbines...Instead, hot air rushes out of the huge, towering mouth of Davey's creation — enough hot air, in fact, to turn a massive turbine that can generate enough power to supply electricity to about 150,000 homes.
Think of it as physics in action, but without the potential for disastrous side effects.
Set to come online in 2015, the output from the first solar tower in Arizona has already been pre-sold in a 30-year agreement with the Southern California Public Power Authority.
While the road ahead looks bright for Mr. Davey, the next challenge is to actually take it off the drawing board and make the tower turn a profit.
For any entrepreneur, that is the ultimate test. Dreams can only take you so far...
http://en.wikipedia.org/wiki/Solar_updraft_tower
p/s: Coal, oil, natural gas, wind, nuclear, and now solar towers, every source is a piece of the greater energy puzzle. Each has a role to play — and that's not a bunch of hot air.