22 June

Tested the thermal mass of the house. I turned the AC off overnight, to see how well the house held the heat. It did brilliantly, dropped only a degree. The heat it stored yesterday was gradually released overnight. So my updated strategy now will be to run the AC all day (also when solar will make it zero cost), to heat the house so that it then carries that heat through the night, when I’ll give the units a rest. This may not work for all homes, our house is double brick and has a lot of thermal mass. But it should for many. It also wasn’t sub-zero last night so will re-assess when we get the next frost. This is the difference between heating/cooling your home, and keeping your home at a constant temperature. Those aren’t the same thing. The former leaves your house hot or cold for most of the day, using lots of energy to heat and cool it in short times. The latter is about achieving a homeostasis, using the house and the AC in partnership.