It's a big consideration when you do a lot of mining. I run GPU miners and it's $100 a month or a bit more at $0.12/kWh to bring in $150 a month in crypto for a single machine.

That's mining at current prices however and the ratio tends to remain stable when the coin goes up and down in value due to the difficulty, if you're mining for a loss expecting an increase in price later that can work as a delayed profit.