by Richard T. Stuebi
Ausra is a leading player in the field of concentrating solar power (CSP), which utilizes mirrors to focus sunlight on a heating element containing a fluid to produce a steam that drives a turbine to generate electricity. In other words, solar thermal electricity – a field that was highly active in the 1980’s only to experience a 15+ year hiatus – is now coming back with a vengeance. Ausra claims that its CSP technology will soon be able to enable electricity production (in sunny desert climates, such as the southwestern U.S.) for about 8-10 cents/kwh.
Moreover, Mr. O’Donnell discussed how Ausra was working on integrating its CSP generation technology with thermal energy storage approaches, so that Ausra’s powerplants would be able to produce electricity not just when the sun is high in the sky — from 7 am to 6 pm — but over a time window more closely aligned to utility peak loads, which stretch from about 10 am to 8 pm. He made the interesting observation that thermal energy storage, using oils and molten salts, is many times more efficient and cost-effective than large-scale energy storage with batteries.
With all of the hype (much of which deserved) for solar photovoltaics (PV), it’s easy to forget about solar thermal approaches, and CSP particularly. Although not as universally applicable as PV, CSP can make a big dent in national energy supply, exploiting only a relatively small fraction of otherwise unusable desert land. In many cases, the gating factor for CSP deployment — just as has been the case for wind energy — will be the availability (or lack thereof) of transmission capacity to electricity load centers.
Mr. O’Donnell made the point that building roads in the U.S. was a local phenomenon subject to a patchwork of regulations and constraints — until President Eisenhower broke down the barriers with the creation of the Interstate Highway System in the 1950’s. He further noted that high-voltage DC technologies now readily available — such as those offered by ABB (NYSE: ABB) — could transmit large blocks of power across the whole continent with losses of only about 11% (excluding the conversion facilities at each terminal).
We in the cleantech community haven’t talked much about it, instead focusing on the sexy/cool generation/storage/consumption technologies, but maybe it’s time to ratchet the discussion about the so-called “smart grid” up to another level.