Space heater, 20 bucks. In the past I chose to heat the bedroom a little on cold days and otherwise suck it up and dress while shivering (no point burning a ton of gas to heat an entire bedroom). Now, I use 1.5 kW for ~3 minutes (0.01 kWh) to have hot air be blown on me while getting dressed in the morning. Because it changes how warm I feel while going downstairs, I also don't need downstairs to be as warm to get wa…
Mostly they run on the very quiet setting (or not at all), but they’ll automatically spin up if someone cooks, farts, opens a window or hits a vape pen.