The first three years in our new home were the coldest three in living memory for me with recorded temperatures as low as -11°C & -6°C during those winters. I had designed to go to just below freezing with no heating so we had to put a small electric heater on, it used about 60W when the temperature was -3°C and 300W when we had -6°C. It was a simple electric convector heater connected to a plug in thermostat.
My house suffered when my wife went away during the cold weather. The house missed her heat and energy use and so did I. I only drink cold water so never boil the kettle, I do my ironing badly in 10 minutes whereas she does our ironing nicely and takes over half an hour, she cooks more, makes cakes, washes more, watches TV more, is here more and is worth at least 75W continuously herself (I do the hovering so that doesn’t count). All that adds up to enough missing energy to let the house notice and for it to be cooler than when she is here — come back as soon as you can I said we need you! (and your heat input both direct and indirect) Nov 2010.
The heat loss for the whole house in October is only 100W so it is very sensitive to incidental heat inputs and the heat from people.
My wife always had cold feet and a cold nose in our old house, no more no though 🙂