U.S. Department of Energy Energy Efficiency and Renewable Energy

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April 26, 2013

I had recently submitted a proposal to dramatically raise the temperature and efficiency of CSP generation by using liquid aluminum as the solar fluid. Is anyone doing anything in this area? Who, and with what results to date? -Edan

SunShot Solar Outreach Partnership

The SunShot Solar Outreach Partnership has been tasked with helping accelerate adoption of photovoltaic (PV) solar at the local level by providing timely and actionable information to local governments.


With the many benefits associated with concentrated solar power (CSP), including its storage capabilities and its ability to minimize production costs, there are a number of organizations working to advance the thermal capacity and efficiency of CSP technologies.

Research and development (R&D) in CSP funded by the Department of Energy (DOE) is targeting new ways to develop high-operating temperature heat-transfer fluids (HTFs) to increase the efficiency and in turn reduce the overall cost of generating electricity via CSP. To date, HTFs can only reach temperatures up to 600 degrees Celsius. [1] Under the Multidisciplinary University Research Initiative (MURI), two university teams – University of California, Los Angeles (UCLA) and University of Arizona - are working to increase the thermal capabilities of HTFs to achieve greater thermal conversion efficiencies. The research team at UCLA is experimenting with different metal alloys to determine which metal alloy can operate at temperatures in excess of 800 degrees Celsius. The University of Arizona is currently testing the use of halide salts with oxy-halide additives at temperatures greater than 800 degrees Celsius.

The National Renewable Energy Laboratory (NREL) and Argonne National Laboratory are also currently testing a high-efficiency thermal energy storage system for CSP. NREL is working with new materials to develop advanced nanofluids and phase-change materials (PCMs), while Argonne National Laboratory is testing the use of chemically reacting working fluids (CRWFs) as HTFs.

Sandia National Laboratories has also conducted several studies on the use of multi-component molten salt and nitrate salts as HTFs in CSP systems.

Should you like to learn more about solar energy technology, visit the Concentrating Solar Power page on the Department of Energy’s website. Also, you can look for archived material from the April 23-25 SunShot Concentrating Solar Power Program in Phoenix, Arizona. This event will feature presentations from awardees on the forefront of CSP technologies who have received some form of funding from the DOE.

[1] (2012, December 5). Multidisciplinary University Research Initiative: High Operating Temperature Fluids. Retrieved from http://www1.eere.energy.gov/solar/sunshot/muri.html.


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