The U.S. Department of Energy announced Thursday that the Southwest Research Institute (SwRI) is the recipient of a $1.2 million grant for a project that could advance the way we store thermal energy.
The federal grant is part of $33 million from the DOE for nine projects across seven states aimed at advancing concentrating solar-thermal (CST) systems technologies for solar fuel production and long-duration energy storage. CST technologies use mirrors to reflect and concentrate sunlight onto a receiver, helping to produce carbon-free clean fuels, heat and storage for a wide variety of applications.
SwRI’s project will demonstrate the impact of low-cost concentrated solar thermal in utility power applications by testing an advanced dual media energy storage system that uses liquid molten salt and solid storage to provide 1 Megawatt of thermal heat for 10 hours, the DOE said in a press release.
These grants are to support the Biden-Harris Administration’s Investing in America Agenda stated the DOE, which aims to “rebuild the economy from the middle-out and bottom-up,” according to the U.S. Department of Interior by “bringing manufacturing back to America after decades of offshoring, and creating new, good-paying jobs,” according to the U.S. Department of Commerce.
“Under the Biden-Harris Administration, DOE continues to invest in the next-generation solar technologies we need to tackle the climate crisis and ensure American scientific innovation remains the envy of the world,” said U.S. Secretary of Energy Jennifer M. Granholm in the statement. “With today’s announcement, DOE is supporting projects that will harness the sun’s energy to power NASA space missions, beer and wine production and everything in between.”
The SwRI project is one of six that will advance thermal energy storage technologies that can provide heat continuously or on demand.
These technologies can be paired with a turbine to produce electricity or serve industrial processes that require heat. Low-temperature concentrating solar-thermal heat can decarbonize the food and beverage industry, for instance by supporting the brewing process, while high temperature heat is useful in chemical production.”
Thermal energy storage technologies for renewables are not necessarily new but their uses and optimization are still being perfected, said Michael Webber, professor of energy resources at the University of Texas at Austin.
Salt is used in California as a thermal energy storage material in solar power plants, Webber noted. Molten salt can store the sun’s thermal energy as heat, which can then be used to generate electricity at any time — including during peak times when the sun isn’t currently shining, he explained. One megawatt of thermal energy is equal to about a third of a megawatt in electric energy, with a single megawatt in electric energy being enough to power 200 homes on a hot Texas day.
Anytime more storage technologies come onto a grid, they are helpful to that grid because that is energy that doesn’t have to be used right then and there, Webber said. Often, wind power, for example, is strongest at night when demand is quite low, meaning without storage technologies much of that energy goes lost.
This type of project by SwRI could be helpful in that it is aiding the Texas grid to have more storage so that electricity can be generated from that heat at a later time, he explained. Cooling systems around Texas — like the one Downtown San Antonio utilizes — do similar work, storing cool energy created overnight when energy demand is less to help cool down buildings during the day when that demand is up, Webber noted.
“There is so much variability with wind and solar, that storage helps us bridge the gaps,” Webber said. “Storage is really valuable because it allows more variability in a grid.”