Parabolic Trough Solar

Noteveryone can win the solar lottery. The world has many sunny places.But, only some where the sun blasts away all year at high intensity.They are places like North Africa. Southern Spain. The Middle East ofcourse. And then, California.

Below is a false-color map of southern California,  (colored) toshow concentration of the sun’s power–as measured in kilowatt hours(kWh), per square meter, per day. The places in the world where solarpower has its greatest opportunity are where the sun hits the earth atand above 6.0 kWh/sq.meter per day. As you can see in the notation,concentrating-solar-power plants have already found their way to theright spots, in the US southwest.

csp map nasa and desertec2 Parabolic Trough Solar

Historically,solar power has been able to capture up to 12%, 14% and even 15% ofthose natural kilowatt levels. But CSP (concentrating solar power) withits parabolic troughsthat heat fluid to run a turbine approach 20% capture. Furthermore,when combined with Salt Tanks, there is the ability to store energy forrelease overnight, and this adds versatility.

The DESERTEC foundation,which composed this graphic, has been formed to deal with the problemsof power generation and also desalination. Interestingly, the twoissues come together nicely. Not only in terms of human need, in placeslike the Southern Mediterranean, North Africa, and Mid-East. But alsoin the dovetailing of technology. There are apparently rather juicypossibilities in both co-generation and double-functioning in the Solar-Desalination process. There has been alot of work done in this area, and one can either read technical papers on the subject–or–follow the conversation on Twitter.

There is no question that industrial strength solar is hugelyexpensive to build. But what’s intriguing about Solar in contrast toWind Power, for example, is the long-life profile and the much reducednumber of moving parts. Some of the CSP (also SEGS–solar energygenerating systems) located in California were first constructed over20 years ago. A potential analytical failure now, in the prospectiveuse of Solar on a wide scale, is the assumption that the price of powergeneration from current sources–coal, natural gas, and nuclear–will notescalate sharply in the next ten years. That is exactly the kind ofwrong turn made in the present, that creates enormous opportunity.


Graphic: Desertec Australia.

Further Viewing: North American solar strength map.