But take a moment for the cherry on top of the cake: during the summer months, the council intends to reverse the process to inject cool air into the tube tunnel, too. Can we get a HALLELUJAH for sustainable energy and cooler tubes?

Also great news is that Transport for London are hoping to find more ways of replicating this scheme. A TfL spokesperson said: “Heat from the London Underground has the potential to be a significant low-carbon energy source. We are also carrying out further research to identify opportunities for similar projects across the network.”

The plan is phase two of the council’s heat network, and the first of it’s kind in Europe. Phase one included the opening of Bunhill Energy Centre which provides “cheaper, greener heat” to around 700 homes in the borough. A map of the network can be viewed here.

Not in Islington, but want green energy?

In 2018 a third of the UK’s electricity came from renewable sources, up from 29.7% in 2017. But how much green energy your house is getting depends on your provider. Demand more renewable energy by switching to Bulb, Good Energy or Green Energy UK, which are the greenest providers in the UK according to the Energy Saving Trust.

Images: Unsplash / Getty

This is how the Northern line could soon be heating your home