party_pants said:

The Rev Dodgson said:

Talking of temperatures:

Sorry to quibble, but I imagine these costs would vary quite a bit from one region of the world to another. I take it that this graph is for North America??

Indeed, in fact just one of the countries of North America:

https://commons.wikimedia.org/wiki/File:Electricity_costs_in_dollars_according_to_data_from_Lazard.png