Examining an Energy Storage Idea 

More than 90% of the energy storage in the United States today is pumped hydro, using surplus energy to pump water uphill, and harvesting that energy by releasing the water to flow downhill through a turbine.  There are several variations on that theme that have some level of merit, e.g., ARES (Advanced Rail Energy Storage), that replaces water in a pipe with heavy train cars on a rail track.

There are barriers to success here, principally that these plants need to be sited in a region that has significant natural elevation changes.

To deal with this issue, I’ve seen a plan for an enormous cylinder made of some high-density material that is raised and lowered into a deep hole that can be bored into the Earth’s surface. The fact that this was 10 years ago and I haven’t heard anything about it since doesn’t bode well.  Keep in mind that all these ideas combine the discoveries of Newton (ca. 1660) and Faraday (ca. 1830), and there’s very little room for improvement.  Batteries will eventually relegate all these ideas into history.

If there is an open window, it’s right now, and it’s a device like the cylinder, in that it has a minimum of moving parts to maintain and doesn’t require a nearby mountain.

Here’s an idea that combines all the worst features of gravitational energy storage into one absurd bundle: linked buckets that take small loads of gravel up and downhill.  I rate this “deliciously bad,” a reference to this old Saturday Night Live sketch.