The Anonymous Widower

Companies Have New Take On Old Energy Storage Tech

The title of this post, is the same as that of this article on Hackaday.

This is the introductory paragraph.

According to Spectrum, several companies are poised to make a splash storing energy with gravity. That sounds fancy and high tech at first, but is it, really? Sure, we usually think of energy storage as some sort of battery, but there are many energy storage systems that use water falling, for example, which is almost what this new technology is all about. Almost, since instead of water these new systems move around multi-ton blocks.

The article gives a review of Energy Vault, Gravitricity and another company called Gravity Power.

This is the article’s take on Gravity Power.

The scale of the weights is hard to imagine. Another company, Gravity Power, claims they could deliver 400 megawatts for 16 hours using an 8 million metric ton piston. There’s no word on how long it takes to bring that piston back to the charged position after the 16 hours, though. A Boeing 757-200, for example, weighs about 100 tons when loaded with fuel and passengers. So imagine 80,000 giant airplanes melted down. It makes Energy Vault’s 35-ton weights seem much more reasonable.

Looking at the Gravity Power web site, their technology is described on this page, where this is the first paragraph.

The GPM (Gravity Power Module) uses a very large piston that is suspended in a deep, water-filled shaft, with sliding seals to prevent leakage around the piston and a return pipe connecting to a pump-turbine at ground level. The piston is comprised of reinforced rock and in some cases concrete for low cost. The shaft is filled with water once, at the start of operations, but is then sealed and no additional water is required.

This graphic from the page explains the technology.

My worry would be water leakage past the piston.

This does sound like an idea from William Armstrong, who was responsible for many things including the hydraulic accumulator.

The picture shows the hydraulic accumulator at Limehouse in London.

I visited the Limehouse Accumulator during Open House in 2012 and wrote about it in Open House – The Limehouse Hydraulic Accumulator.

 

 

 

January 9, 2021 Posted by | Energy, Energy Storage | , , , | 1 Comment