Scientists at National Renewable Energy Laboratory (NREL) of the US Department of Energy have recommended using silica sands as a means to store excess solar and wind electricity. Silica sands are a stable and inexpensive product with varying prices from $30 to $50 per ton.
Economic Long-Duration Electricity Storage by Using Low-Cost Thermal Energy Storage and High-Efficiency Power Cycle (ENDURING) is a scalable method that can be put practically anywhere, according to the research team.
The baseline system, which has a storage capacity of approximately 26,000 MWh, operates by heating the silica particles to roughly 1,200 degrees Celsius using a grid of electric resistive heating components and depositing them in insulated concrete silos for the thermal energy storage.
According to the NREL researchers, hot particles are usually gravity-fed via a heat exchanger when energy is required, heating and pressurizing the working gas within to power the spin generators and turbomachinery that generate power for the grid. “Once released, the spent, the cold particles are stored in insulated silos until conditions (as well as economics) are favorable for charging again.”
They claim that the suggested storage technology could be implemented for $2 to $4 per kWh and that it could be hosted by current infrastructure from defunct coal as well as gas-fired power plants. It may also serve as a constant supply of heat for chemical and industrial activities.
As per NREL researcher Patrick Davenport, “Concrete and Sand silos containing refractory insulation are fairly affordable materials that potentially lead to low-cost energy storage.” “Traditional four-hour storage methods don’t scale well at the grid or the scale of a metropolis. This technique makes great sense now that we require large-scale energy storage.” The planned system’s heat exchangers and prototype heaters are currently being tested at high temperatures.
The National Renewable Energy Laboratory (NREL) focuses on integrating renewable energy, energy systems, energy efficiency, and sustainable transportation research and growth. The Alliance for Sustainable Energy, a joint project between MRIGlobal and Battelle, operates NREL, a federally financed research and development center funded by the Department of Energy and run by Alliance for Sustainable Energy. The National Center for Photovoltaics, the National Wind Technology Center, and the National Bioenergy Center are all located at NREL in Golden, Colorado.
The Solar Energy Research Institute was established under Solar Energy Research, Development, and Demonstration Act of 1974[a], which opened its doors in 1977 and was operated by MRIGlobal until its closure in 2011. During the administration of Jimmy Carter, the agency’s operations in solar energy moved beyond research and creation to include efforts to disseminate information about already-existing technology such as passive solar energy.