I work for a.company that melts steel. Cost of electric is a very large issue. We pay workers extra to work overnight shifts when electric is cheaper and shut down during the day. We also shutdown for annual maintenance in December when Christmas lights raise electric costs.. not one that melts metal, but I know one plant runs 5 months and does maintenance the other 7.

Note, the above is as of 10 years ago. Now wind provides most electric so hours may be different to account for that.

> After you've bought the building, the smelter, and the guy to operate it, the cost of electricity to smelt aluminum is negligible.

Electricity is the biggest expense in aluminium production. There is a reason it is nicknamed "solid electricity".