My housemate went away for the weekend… leaving me to my own devices. So I tried having the furnace and all space heaters off for 36 hours (Friday eve to Sunday morning), just to see what would happen. We were at the tail end of a cold snap on Friday (below zero F), but now it’s warmed up considerably outside, to 18F/-8C.
The only significant sources of heat created in the house during this time were:
a) Making one mug of coffee each morning
a) A hot shower Saturday afternoon (hot water turned on about 20 minutes)
b) Metabolic body heat of myself (roughly 100W) part-time and three well-insulated cats (estimated total 40W) full-time.
a) The electric blanket: Used at half-power (approximately 90W) about 8 hours each night– Friday night on the sofa in the bunker, Saturday night in bedroom.
And here’s the graph of temps outside, in the kitchen/bunker, and the bedroom.
As you can see, the house really doesn’t cool off very fast. Saturday morning the bedroom actually warmed slightly, of its own accord, which is mysterious– could be because it gets some morning sun? You can see that making coffee has a rapid effect on the air temp, though in terms of actual heat this is pretty trivial and is rapidly absorbed into the tile and steel heat-sinks of the kitchen.
The electric blanket kept me extremely warm (I had to turn it down several times last night), in spite of using only a lightbulb’s worth of electricity. Interestingly, the e-blanket set on 50% power has roughly the same warmth as another human being sharing the bed… perhaps not a coincidence.