SPECTRUM: China Stumbles on Path to Solar Thermal Supremacy

In the final days of 2018 a 100-megawatt solar thermal generating station capable of running around-the-clock, 365-days-a-year connected to the Northwest China regional power grid. It was a race against time to commission the plant in temperatures as low as -20 celsius—and one that plant designer and builder Beijing Shouhang Resources Saving Co could not afford to lose.

“We must finish on time. Otherwise we may face a heavy financial problem,” says Chen Han, Shouhang’s director for international markets.

Shouhang was racing to beat the Chinese government’s December 31, 2018 deadline to secure a guaranteed price for the plant’s power. The deadline was part of an aggressive demonstration program launched in September 2016 to slash the cost of solar thermal power and catapult Chinese firms to the head of the global pack—much as China did with solar photovoltaics.

Alas, a little more than two years later, China has stumbled on the path to solar thermal supremacy. While Shouhang’s and two more of the program’s 20 approved projects met the deadline, four others were cancelled last year and the remaining 13 projects are in limbo. Continue reading “SPECTRUM: China Stumbles on Path to Solar Thermal Supremacy”

Solar Towers Not Avian Annihilators

Solar power towers have had a reputation as alleged avian vaporizers since preliminary reports of birds being burned in mid-air at California’s Ivanpah solar thermal plant. Their reputation was muddied even more during tests early this year at SolarReserve’s Crescent Dunes power tower, whose intense beams of reflected light recently began generating power in Nevada. California public radio station KCET reported that as many as 150 birds were killed during one six-hour test in January. It is obviously upsetting to imagine birds ignited in the name of renewable energy. But avian mortality is a downside common to many modern human creations—including buildings, highways, and powerlines. Full data on bird mortality at Ivanpah, macabre as it might be, shows the death rate to be small and likely of little ecological significance. “The data does support a low level of avian mortalities and hopefully, through adaptive management and deterrence, it will go even lower,” says Magdalena Rodriguez, a senior environmental scientist with the California Department of Fish and Wildlife. Continue reading “Solar Towers Not Avian Annihilators”

The Other Solar Power

Solar thermal power cuts a fascinating contrast with solar photovoltaics and wind turbines — today’s leading renewable energy technologies — besting one on price and the other on quality. Little surprise then that it is being selected for power plants equal in output to large wind farms and ten-times the size of the largest photovoltaic installations.

Whereas photovoltaics employ semiconductors to directly convert sunlight into electricity, solar thermal power stations convert sunlight into heat to generate steam and drive a turbine. This roundabout is, ironically, a huge money-saver. The Abengoa thermal solar power towers in Sevillemirrors, pipes, pumps and steam turbines that form a solar thermal plant cost less than half than an equivalently powerful array of photovoltaics.

Solar thermal cannot similarly challenge wind turbines on cost (at least not at present). But solar thermal plants can store some of the energy they capture and, as a result, produce a much steadier and more reliable supply of electricity than the famously variable wind turbine.

So why then did we hear so much about solar photovoltaics over the past decade and sol little of solar thermal? Because the latter is inherently utility-scale technology, whereas photovoltaic panels provide value one rooftop at a time. Fred Morse, a solar thermal pioneer and currently senior advisor to renewable energy developer Abengoa Solar, likens it to a bakery operating through the depression. “If you had a bakery and you sold cookies or big wedding cakes, during hard times you could sell a lot of cookies,” says Morse. “PV has little niche markets and it could grow and grow and as the price came down it expanded those markets to where it is today.”

These days, thanks to state and (albeit on-again-off-again) federal incentives and record fuel prices, solar power is back to wedding cakes.

For more, check out “Solar without the Panels”

add to del.icio.us : Add to Blinkslist : add to furl : Digg it : add to ma.gnolia : Stumble It! : add to simpy : seed the vine : : :