Soldato
I think a lot of that depends on your lifestyle while WFH.
A laptop and small monitor really doesn't take much to power.
But if you're someone who has the heating on 8 hours a day whilst home, boils a full kettle every few hours, and uses the oven to warm up some lunch, then yes i can imagine costs whilst WFH are going to get rather expensive.
When we first started WFH and the kids were off school as well, our electricity bill was higher than charging the Zoe to drive to work!