Working from home moved a chunk of energy use out of the office and onto your own bill, and while the gadgets get the blame, the real cost is somewhere less obvious. Knowing where it actually goes lets you keep the home-working bill modest rather than letting it creep up unnoticed.
What home working adds
By far the biggest addition is heating. An empty house on a workday used to coast along cool until you got home; now it needs to be warm all day while you are in it, and daytime heating in winter is the single largest extra cost of working from home. The electronics, by contrast, are minor: a laptop draws very little, and even a desktop with a couple of monitors is small next to the heating, as the standby power and device guides explain. Add a few cups of tea from the kettle and some extra lighting, and the device side stays modest.
What it costs
Because heating dominates, your home-working cost depends mostly on the weather and your house: high through a cold winter, almost nothing in summer. The electricity for your kit is a small, steady addition you can estimate by putting your computer and monitor wattage through the running cost calculator for the hours you work. Do that and you will see the heating is the thing worth managing, not the laptop.
How to cut it
The trick is to stop heating the whole house when you only occupy one room of it. Work in one room and heat that room rather than the entire home, turning down the radiator valves elsewhere and setting the main thermostat to suit where you actually are. A small amount of targeted heat, or even a heated throw while you sit still at a desk, costs far less than warming every room you are not in. Layer up, keep the door shut, and let the rest of the house stay cool. Switch your kit and screens off at the end of the day rather than leaving them idling.
The commute trade-off
It is worth keeping the whole ledger in view. Working from home adds to your home energy bill, but it removes the cost and energy of commuting, which for many people is far larger than the extra heating, especially if the commute was by car. So while your household bill goes up, your total spending and energy use often go down once the fuel or fares you are no longer paying are counted. The home-working cost is real, but it is usually a transfer from a bigger expense rather than a brand-new one.
The bottom line
The energy cost of working from home is mostly daytime heating, not the computer, so the way to control it is to heat the room you work in rather than the whole house, using zoning, a lower thermostat and a bit of layering. Against that, you save the commute, which often more than covers the extra. Manage the heating sensibly and home working need not cost much at all.