Phase Change Matters

Using a novel modeling tool for concentrated solar power, Spanish researchers have designed a more efficient storage system employing multilayered phase change material. The CSP system has a theoretical thermal efficiency of more than 74 percent and requires only a third of the molten salt needed in traditional two-tank systems.

The system was first described in "A New Thermocline-PCM Thermal Storage Concept for CSP Plants. Numerical Analysis and Perspectives," a paper presented at SolarPACES 2013. "The key aspect of this new concept," the researchers wrote, "is the inclusion of PCM layers at both ends of the tank, whose fusion temperatures are conveniently chosen to be inside the 'admissible' temperature ranges for the outlet of both charge and discharge processes."

Colorado State University's Center for the New Energy Economy has released a summary of advanced energy legislation passed in U.S. states in 2014. Some 430 advanced energy bills became law, down from 713 in 2013. Changes to renewable portfolio standards were enacted in 12 states, including Maine, South Carolina and Massachusetts.

http://www.aeltracker.org/graphics/uploads/CNEE-2014-Advanced-Energy-Legislation-End-of-Year-Summary.pdf