Make or Break Time for Concentrating Solar


The San Luis Valley in southern Colorado is a place of desolate beauty, roughly the size of New Hampshire, the driest high-elevation area in the United States. It’s also becoming a proving ground for both wind and solar power projects, some of them of vast scale. This week the Saguache County Board of Commissioners voted to issue a permit for a sprawling solar power facility that would generate 200 megawatts (MW) – three times the electricity of the three solar plants already existing in the Valley.

The San Luis project, being developed by Santa Monica, Calif.-based SolarReserve, is also noteworthy because it uses concentrating solar technology, which uses arrays of sun-tracking mirrors, known as heliostats, to amplify and focus the sun’s energy onto a fluid – water or molten salt – that is heated to make steam. Covering 4,000 acres, SolarReserve’s plant will include two 656-foot towers surrounded by 1,700 acres of heliostats. Although SolarReserve has a contract with Xcel Energy for 100 MW of transmission capacity on a nearby Xcel power line, it has not yet found a buyer for power from the complex.

A technology with potential advantages over conventional, photovoltaic-based solar power, concentrating solar power (CSP) has not yet fulfilled its promise and may be reaching a make-or-break phase in its development. The San Luis Valley announcement came just as an auction was scheduled to sell off the assets of Maricopa Solar, a pilot CSP project built by Stirling Energy Systems, which went bankrupt last September. The fact is that CSP, besides being a more potent form of energy collection, presents certain disadvantages as well, the most obvious being that many CSP systems require copious amounts of water to cool the mirrors and lenses – a significant downside in a desert environment like the San Luis Valley or like California’s Mojave Desert, the setting of the 392 MW Ivanpah plant being built by BrightSource Energy. Dry cooling systems are becoming more prevalent, but are also more expensive.

BrightSource was also in the news this week as it filed for an initial public offering in which it plans to raise $182.5 million. Backed by Google and by power producer NRG Energy, BrightSource is also the recipient of a $1.6 billion loan guarantee from the U.S. Department of Energy – a fact that could become politically inconvenient once it’s a publicly traded company with millions in shareholder cash. BrightSource already has 13 contracts to sell power to utilities including PG&E Corp. and Edison International. The IPO is scheduled for mid-April, according to Bloomberg.

Several other companies including Acciona SA of Spain, German tech giant Siemens AG, and ABB Ltd. of Switzerland are trying to bring CSP to market. Some of these companies recently launched a trade group called the Concentrating Solar Power Alliance to “educate” (i.e., lobby) U.S. regulators and lawmakers on the benefits of CSP technology. By the time the nascent industry gathers in San Diego for the 4th annual Concentrating Solar Thermal Power conference, on April 18th and 19th, the near-term prospects for CSP are likely to be clearer.

Article by Richard Martin, appearing courtesy the Matter Network.



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