6 Solar technologies to power the world (CNNMoney.com)

[eppur_se_muova]

At last, solar energy is big enough and cheap enough to power electrical grids. Business 2.0 features the latest projects under the sun.

By Todd Woody, Business 2.0 Magazine assistant managing editor

Solar trees

The Stirling dish is a 30-year-old technology that's just now becoming cost-effective thanks to big solar-power orders from utilities. In time, 70,000 of these "solar trees" planted in the Mojave Desert by Stirling Energy Systems of Phoenix could power a million homes.

Distributed tower power

What happens if the sun's not shining? Bright Source Energy has a solution called distributed tower power: Mirrors focus the sun's rays on a boiler, creating steam which drives a generator. Natural gas can be used to power the plant when the sun isn't shining.

Heliostat concentrator

In southeastern Australia, Solar Systems will build a heliostat concentrator photovoltaic array of mirrors which focuses sunlight on high-efficiency solar cells to produce electricity.

Microdishes

GreenVolts, a San Francisco startup, is building arrays of microdishes - dinner-plate-sized mirrors that concentrate the the sun on an efficient solar cell. Small clusters of these microdishes are compact enough to be installed near cities, plugging directly into the grid to relieve overloaded substations.
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more: http://money.cnn.com/galleries/2007/biz2/0705/gallery.solar_tech.biz2/4.html

Hey, they're only business journos -- not even up to the standards of regular journos.

No mention of the fact that "powering the plant" with natural gas is NOT carbon-neutral (only actual $$$ amounts count), nor that there are ways to accumulate energy during the day for release at night.

Interesting that the last entry is one that was built in the 1980's -- before the Reagan/Bush policy of neglecting alternative energy caught up with it.

[Dogmudgeon]

1. When will we have 100 GWe of this?

That's the problem.

That's always been the problem.

Solar energy is workable. There are at least a dozen good ways to exploit it. But it still accounts for maybe 1/2 of 1% of our total energy capacity -- and solar energy runs at about 30% capacity overall. 0.15% of what we use. At 30% growth per year, it will take two decades just to get to where nuclear or hydro power are now. But the capacity to manufacture solar power technology is itself limited, and the factories are running at full load.

Since this modern green wave hit about five years ago, I have seen thousands of Good Ideas and "Technologies That Will Save The World", but almost no action. There is a large subcurrent of "Anything But Nuclear" sentiment, in spite of the fact that it's a nearly ideal source of base-load energy. But while it's easier to get investment money for reactors, the problem cuts across all viable energy systems. There is lots of talk, but little action. Is it any wonder why nearly every wind farm in America is very visible from one or more Interstate highways? In my area, PECO puts them near I-80 and I-95. It's a case of "look at the cool-ass windmills while the real energy is coming from remotely-sited filthy furnaces".

Coal is doing very well, indeed. And there is a major market run on food crop based ethanol.

Why not save ourselves the trouble and just hand out cyanide pills?

We need to invest hundreds of billions of dollars, just this year alone, to get ANY "green" scheme off the ground. It is likely that we will need to invest several trillion in fundamental infrastructure over the next decade if we wish to avoid serious economic and social "dislocation". Yet all our money is going into the maw of the Iraq war. Very little money has been committed to developing anything other than coal-based energy.

Many of us would call for an "Energy Manhattan Project". What we need is simply to adequately fund all of these modern energy technologies -- including nuclear energy. We need an expansive, rather than expansionary, energy regime. We need serious investment, labor, and public participation in building for at least half a century's energy demand.

But we're doing nothing to substantially alter the status quo ante. We'll choke on coal soot before we decide to commit to the 500 nuclear reactors or million wind turbines we need. We'll spend ten dollars on the lie of "Clean Coal" before we spend a nickel on anything that doesn't combust. And we'll plant inedible crops for ethanol on every remaining patch of soil before we get rid of car culture.

In the short run, we'll be okay. We will think we have beaten the odds. But I fear the reckoning.

--p!