"CSP Today" Offers Great Coverage of Concentrated Solar Power
Twas the night before Christmas and all through the house,
If I weren’t covering renewables, I’d feel like a louse.
Or perhaps….
About the lack of clean energy I continue to grouse.
Be this as it may….
I look forward to the e-newsletters I receive once or twice a week from CSP Today
on the latest news in concentrated solar power (aka solar thermal). These people do a world class job in keeping up with the industry. Although it’s been almost two years since I had lunch in New York City with Belen Gallego, the publication’s director, I can recall quite clearly how animated she was about the promise that this technology represents and how excited she was to tell the world about it.
The challenge here, as always, is economic. How can we bring down the cost per watt of dispatchable power? For my money, the most credible answer lies in the technology of a start-up in Northern California, Ahura Energy Solutions, who has figured out how to track the sun without expensive motors, gears, etc.
Merry Christmas, everyone.
Concentrated solar power does not need to be thermal. It is possible to use mirrors or Fresnel lenses to concentrate sunlight on PV cells and has been done.
Concentrated SP has both advantages and disadvantages. It can be more efficient and cost less per watt, for either thermal or PV systems. On the other hand, it depends on direct sunlight and ceases to work on cloudy days. Non-concentrated systems can work even on cloudy days although they will generate less power on cloudy days.
Thermal systems can be, and have been, designed to store heat in molten salt tanks so that they can continue to generate power for a while when there is no sunlight. The tanks commonly contain a mixture of 40% KNO3 and 60% NaNO3, sometimes using a thermocline system to maintain temperature stratification. One in Spain has been designed to have enough heat storage for seven hours.
Improved technology may significantly increase storage capacity, but there is currently no energy storage technology available which is adequate to make intermittent energy generation systems practical in all locations. Improved sun tracking helps to a limited degree, but cannot cause power to be generated when there is no sunlight.
I’ve just ordered the book “Carbon-free, Nuclear-free: Roadmap…” by Makhijani, from Barnes and Nobel. The author asserts that renewables are capable of doing the job alone. However, in his youtube presentation, he does not address the problem of providing reliable power from intermittent sources; I shall see if he addresses that problem adequately in his book. The usual way that problem is addressed is by asserting that it has been solved, but without providing credible proof.
I continue to read opposing viewpoints, but remain convinced that renewable energy sources have only a limited rôle to play.