Using gravity to store electricity

We’d all like to use more energy generated from renewable sources than carbon technologies but one thing traditional power generation has over renewables like solar and wind is that if we need more energy at some point, we can throw more coal or gas into the furnaces, but we can’t make the wind blow or the sun shine. 

That’s where this brilliant idea comes in. When there’s excess energy from the wind turbines it’s used to push heavy electric trains up a hill. When we need energy, but the wind isn’t blowing or the sun isn’t shining, gravity pulls the trains back down the hill and they become mini power stations and generate electricity.