A White-Hot Molten Silicon "Sun" Could Power 100,000 Homes

"Sun in a Box"

Much of the world's electricity is generated in real time — power plants fuel our homes when we need it, as we need it, and excess energy generally goes to waste.

With fossil fuels, this isn't a huge problem; we can always burn more gas or oil. But wind turbines and solar panels produce power only when the wind is blowing or sun is shining. Energy storage for those mediums will pose a key challenge during the world's transition to renewable energy energy.

That's why it's exciting that scientists from MIT and the Georgia Institute of Technology say they've found a new solution, which they call a "sun in a box." The box takes the form of an insulated graphite silo that's full of "white-hot molten silicon."

Everything the Light Touches

The sun in a box works like giant rechargeable battery, according to research published last month in the academic journal Energy & Environmental Science, storing excess electricity as heat. Then, if people in the area need power in the evening when their solar panels aren't generating power, photovoltaic within the silo capture the glowing silicon's light and convert it back into useable electricity.

The engineers who worked on the project, which has the official and way-less-fun name of the Thermal Energy Grid Storage-Multi-Junction Photovoltaics (TEGS-MPV), think that it could be deployed in energy grids pretty much anywhere in the world, according to an MIT press release.

Solar City

Based on their preliminary tests, the scientists project that a single TEGS-MPV storage tank would be able to store enough power that a community of 100,000 homes could rely solely on renewable energy sources and not face interruptions when the sun goes down or the wind stops blowing.

These are, of course, early tests, and there will surely be unforeseen challenges to bringing this energy system to scale and actually using it in the real world. But if we expect to avoid the worst effects of climate change, we'll need to solve the problem of renewable energy storage. It's nice to start seeing some answers.

READ MORE: “Sun in a box” would store renewable energy for the grid [MIT News]

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