May 7, 2014 – Areva says it has begun operations of its full-scale molten salt energy storage demonstration plant, which is partially funded by the U.S. Department of Energy (DoE) and being carried out at Sandia National Laboratories’ National Solar Thermal Test Facility in Albuquerque, N.M.

Areva’s solar team and Sandia’s molten salt technology experts have developed an approach to energy storage that combines the molten salt test loop (MSTL) with Areva’s compact linear fresnel reflector (CLFR) applications. The result is a reliable and competitive solution, says Areva, that optimizes the benefits of CLFR technology by ensuring that the energy captured can be dispatched night or day through the use of molten salt storage.

“Together, these technologies provide a solution to capture the sun’s energy during the day and economically deliver renewable power to the grid at any time,” said Sam Shakir, CEO of Areva Solar.

The CLFR design uses an array of mirrors to concentrate the sun’s energy on an elevated evacuated tube receiver to heat a working fluid—in this case, molten salt. The system draws molten salt from a cold (290C) tank, uses the heat from the mirrors to heat it to as high as 550C, and passes that hot liquid to a separate tank for storage. When needed, the high-temperature molten salt passes through a heat exchanger to produce steam for electricity generation. The molten salt then returns to the cold tank and the process is repeated in a closed-loop system.

Successful test results demonstrate that the use of molten salt as a working fluid enables high-temperature operations, reduces the volume of salt needed for storage, and removes the need for two sets of heat exchangers in the system, explains Areva. These efficiencies decrease the overall cost and complexity of the system. As part of the project, Areva says it will also study the optimization of operation and maintenance costs related to molten salt management “in a real-world environment”.