Thermal Energy Grid Storage (TEGS) Using Multi-Junction Photovoltaics (MPV)
In ideal conditions, renewable energy can be cost competitive with fossil-based energy. In less than ideal conditions, renewables still face intermittency problems that traditional energy supplies do not. This limits the extent to which grid operators can rely on renewable energy, and is why, without energy storage, renewables account for 0-15% of power on the grid at any time. Grid-scale storage is critical to increased renewable energy on the grid, to replace emissions-heavy conventional power sources.
Project Innovation + Advantages:
MIT will develop critical components for a new, cost-effective, high efficiency power storage system to store renewable energy at grid scale and discharge it on demand. The system combines low-cost, very high-temperature energy storage with high-efficiency, innovative semiconductor converters used to transform heat into electricity. MIT’s technology would store heat at temperatures above 2000°C (3600°F) and convert it to electricity using specialized photovoltaic cells designed to remain efficient under the intense infrared heat a high-temperature emitter radiates. MIT will also develop several infrastructure components that will enable stable operations for long periods without any discernable loss in conversion efficiency.
The project aims to develop a grid level electricity storage system that can be used to buffer excess electricity on the grid from any source, and discharge it on demand at a later time.
Cost-effective thermal energy storage would enable increased use of varied domestic energy resources making the nation's energy supplies more diverse and less prone to disruption.
Because CO2 emissions associated with electricity generation comprise 28% of total emissions in the U.S., increased grid-scale storage could reduce emissions by 28%, as it would enable greater use of renewables.
MIT’s system could create a levelized storage cost that is half the price of pumped hydroelectricity—currently the cheapest storage technology available—and without geographic limitations.