As the coal industry declines, we are left to look for new and greener ways to generate power for a growing population. It turns out that while we might not be able to mine coal for much longer, we still might have a use for the giant holes we’ve dug in the process.

They are calling it Gravitricity and it involves dropping giant weights down the length of the shafts and using the force of gravity to generate power. “Our patented technology is based on a simple principle: raising and lowering a heavy weight to store energy.” Think of it as the same kind of thing as a pendulum in a clock, but on a massive scale.

The new system has a lot of benefits. It can be used on shafts ranging from 500-5,000 feet deep, each shaft should be good for fifty years of usage, and the set up is relatively low cost because the holes have already been dug. Also, unlike solar, wind, or hydroelectric power, Gravitricity’ can be used anywhere that has an existing mine shaft, or where you can dig a hole. It also isn’t used to store power, so there’s no issues involving costly or environmentally dangerous batteries.

Sadly, we aren’t quite ready to power West Virginia with their closed down coal mines yet, but the startup doing the most work in the field just got a million dollar grant to get the tech to where it could be commercially viable.

Source: Inhabitat