Engineers at MIT have tested a concept design for a system that stores renewable energy in molten silicon. Excess energy created in times of sunlight or wind can be converted into electricity as it’s needed. It’s expected to be much more affordable than lithium-ion batteries and to work on a larger scale.
The system, called “Thermal Energy Grid Storage-Multi-Junction Photovoltaics” or TEGS-MPV, works by capturing excess energy created in existing systems such as solar cell arrays. It uses this excess energy to heat enormous tanks made of graphite, filled with silicon. Molten silicone is transported from a “cold” tank kept at about 3,500°F to a hot tank that’s warmed up to 4,300°F as energy generated from paired systems pours in. Pumping the hot silicone back into the “cold” tank through a specialized set of tubes captures the heat difference as energy, allowing the system to act as a giant rechargeable battery.
Researchers point at the efficiency of storing energy as heat rather than electricity as a major advantage of the new design. They have affectionately coined it a “sun in a box”. Researchers are also excited that unlike hydroelectric and other energy storing mediums, the TEGS-MPV system could work in a host of different locations.
Energy storage breakthroughs can be big news for Alaska, where large variabilities between seasons can mean that entire renewable systems function only during one or two parts of the year. Even during peak production times, excess energy is wasted throughout the process.
You can learn more about the “sun in a box” by clicking here.