Subterranean thermal energy storage system for concentrating solar power

Researchers in the Stanford School of Sustainability have patented a sustainable, cost-effective, scalable subsurface energy storage system with the potential to revolutionize solar thermal energy storage by making solar energy available 24/7 for a wide range of industrial applications. Subsurface thermal energy storage addresses key challenges faced by solar thermal energy: intermittency and the need for large-scale, long-term storage. Instead of using above ground insulated tanks with exotic molten salts for energy storage, this method (see Figure 1) uses the vast pore volume of depleted oil and gas fields for heat storage, which reduces above-ground infrastructure, cuts costs, increases the amount of energy that may be stored, is scalable, and potentially reduces heat losses. The heat is stored in the reservoir until there is a demand for energy. The energy is brought to the surface and can be used to generate electricity or process heat, making the system adaptable for different industrial applications, and potentially converting solar thermal energy to a base load renewable energy.