The New York Times has an article on Alcoa's interest in making reflective solar troughs for the solar thermal power industry - Aluminium Maker Eyes Solar Industry. Perhaps Alcoa Australia should have looked harder at some form of CSP (perhaps combined with gas or geothermal energy) for their Australian operations.
Alcoa, the aluminum giant, is testing a new type of solar technology that the company said it believed will lower the cost of renewable energy.
The company has replaced the glass in parabolic troughs with reflective aluminum and integrated the mirror into a single structure.
Parabolic troughs focus sunlight on liquid-filled receivers suspended over the mirrors to create steam that drives an electricity-generating turbine. Parabolic trough technology has been in modern use in solar power plants since the early 1980s, but Alcoa executives said they saw an opportunity to refine the technology and get a foothold in the rapidly expanding renewable energy market.
“If you go out and look behind large parabolic troughs, you’ll find an elaborate truss structure,” said Rick Winter, a technology executive with Alcoa. “From our understanding of aerospace structures, we said if we can modify the wing box design used in aircraft and integrate a parabolic reflector, it would give us a light and stiff structure that would fundamentally affect the cost equation.” ...
Current solar troughs use glass mirrors that are formed in the shape of a parabola and then attached to a support structure made of aluminum or steel. The executives said they estimate that the all-aluminum Alcoa parabolic trough, which is being tested at the National Renewable Energy Laboratory in Colorado, will cut the price of a solar field by 20 percent due to lower installation costs.
Aluminum manufacturing, however, is the nation’s most energy-intensive industry, according to the Energy Department. Mr. Kerns said Alcoa had not performed a life-cycle analysis of the total energy costs and benefits of deploying such parabolic troughs, but noted that the company planned to use recycled materials to make the solar collectors.
“We can take the energy intensity out, as much of the structural elements have the potential to use recycled aluminum,” Mr. Kerns said.
Alcoa will face competition from start-ups like SkyFuel, which has developed a lighter-weight parabolic trough that uses a reflective film instead of glass mirrors.
The Alcoa executives said the company planned to have its solar trough in commercial production within two to three years.