NREL and Alcoa Test Concentrating Solar Power Technology in Colorado

NREL and Alcoa recently installed a new Alcoa-designed Concentrating Solar Power parabolic trough at NREL’s test facility in Golden, Colo., USA. The series of tests will measure the 20-foot by 46-foot collector’s efficiency to generate energy and evaluate its structural performance. This round of validation at NREL follows successful tests at Alcoa Technical Center outside of Pittsburgh, Pa., USA.

"NREL is looking forward to performing outdoor efficiency tests on the innovative new parabolic trough collector developed by Alcoa,” said Dr. Chuck Kutscher, Manager, NREL Thermal Systems Group. “We are excited to see a major U.S.-based manufacturer entering the Concentrating Solar Power market through the financial support of the U.S. Department of Energy’s Funding Opportunity Announcement Program."

Currently, commercial Concentrating Solar Power systems installed to date use glass mirrors to reflect and concentrate sunlight onto receivers that collect the solar energy and convert it to heat. This thermal energy can then be used to produce utility scale electricity via a steam turbine.

Instead of glass mirrors, the new Alcoa solution uses highly-reflective aluminum mirrors, which are more durable and environmentally-friendly than fragile glass-based mirrors. The Alcoa design solution enables high-volume manufacturing techniques to lower installation costs, plus its monolithic structure enables a simple “drop-in-place” collector for easy installation. The Alcoa design includes sheet, extrusions and fasteners.

The new Alcoa CSP design leverages high volume manufacturing and assembly approaches utilized in the aerospace and automotive markets as well as the Company’s materials and technology leadership to lower the cost of CSP trough systems.

“We understand the end-customers’ need to lower the capital investment in these systems in order to lower the cost of energy,” said Dr. Eric F. M. Winter, Alcoa’s Director of Development Laboratories. “After listening to numerous industry experts, our multi-faceted team combined its materials knowledge with design, manufacturing and engineered finishes capabilities to develop a system solution that enables manufacturers to more easily scale up to meet the growing demand for this solar technology.”

One of the benefits of Concentrating Solar Power technology is that thermal energy can be stored and drawn upon during short periods of clouds and at night. Therefore, the technology provides better grid stability and increased capacity factors compared to photovoltaic applications.

The project is being partially funded by a US$2.1 million DOE grant. Test results are expected by the second quarter of 2010, after which the system will enter its next level of large-scale testing.

“We are proud to partner with the Department of Energy to develop a new, clean, reliable and affordable source of electricity,” said Scott Kerns, Vice President and General Manager of Alcoa Transportation Products. “Alcoa has a long history of developing sustainable solutions for its customers, and aluminum – which can be infinitely recycled – is a natural fit for this green energy solution.”

www.alcoa.com