A research team led by Purdue has developed a new material and process for manufacturing to make using and storing solar power − in the form of heat energy − more efficient for using as energy.
The developments make the process of generating solar energy much cheaper, and could increase the percentage of electricity created through solar power in the U.S. from the less than 2 percent currently generated to rival the more formidable over 60 percent generated from fossil fuels in the U.S.
"Storing solar energy as heat can already be cheaper than storing energy via batteries," Kenneth Sandhage, Purdue's Reilly Professor of Materials Engineering said in a press release. "So the next step is reducing the cost of generating electricity from the sun's heat with the added benefit of zero greenhouse gas emissions.”
Solar power isn't only generated through panels, but also can be concentrated in solar power plants that run on heat energy. These plants concentrate a lot of light into a small area by using lenses or mirrors, generating heat that is then transferred to molten salt. This heat is transferred to a "working" fluid which expands and spins a turbine, creating energy. For solar panel energy to be cheaper, the engine would need to run hotter in order to generate more electricity for the same amount of heat.
Sandhage and Asegun Henry, a professor at the Massachusetts Institute of Technology, worked to create a composite material similar to those they had previously used to handle high heat and pressure for applications like solid-fuel rocket nozzles. A composite of zirconium carbide and tungsten was promising.
Plates of the composite were made by Purdue researchers with customizable channels in order to adjust the exchange of heat based on simulations conducted by Devesh Ranjan's team at Georgia Tech. Research teams at both Oak Ridge National Laboratory and the University of Wisconsin-Madison ran tests to show that the composite material could be successfully adjusted to higher temperatures and increased pressures necessary for generating solar-powered electricity at a lower price.
Researchers at Purdue and Georgia Tech ran economic analyses showing that manufacturing the heat exchangers could be cheaper than those made of stainless steel or nickel-based alloys.
In the release Sandhage stated that "this technology would allow for large-scale penetration of renewable solar energy into the electricity grid, (which) would mean dramatic reductions in man-made carbon dioxide emissions from electricity production.”
The team has filed a patent application for this advancement. This research is supported by the U.S. Department of Energy.