The easiest way to squirrel away electricity in times of plenty, for use when it is scarce, is to pump water uphill with it. Such pumped storage is widely employed where local geography and hydrology permit, but it does need two basins, at different heights, to act as reservoirs, and a supply of water to fill them.
[...] Where geography does not favour pumped storage, though, the search is on for alternatives. These range from giant batteries, via caverns filled with compressed air, to huge flywheels made of carbon-fibre composites. But one firm looking into the matter eschews all these. It has stuck with the logic of pumped storage, which is to move large amounts of matter up and down hills. The difference is that in its case the matter is solid.
The firm in question calls itself ARES, which stands for Advanced Rail Energy Storage.
[...] The rocks stand in for the water in a pumped-storage system. They are carried up- and downhill by a train that is thus the equivalent of the turbines. The track the train runs on is equivalent to the tunnel. And the motors that drive the train act, like the electrical kit of a pumped-storage turbine, as generators when they run in reverse as the train rolls backwards downhill, pulled by gravity.
(Score: 2) by Justin Case on Sunday December 04 2016, @02:41PM
So you are apparently unaware that heavy freight trains have been negotiating steep grades for over a century now? Perhaps someone has thought of these problems and come up with a solution? Like... (can you work it out before I tell you?) ... brakes!
(Score: 0) by Anonymous Coward on Sunday December 04 2016, @08:02PM
Perhaps a re-reading of the post you answered would be enlightening. I'm thinking such a thing as brake FAILURE was taken into account. Brake failures, while infrequent, do happen.