Energy consumption in the home could readily be reduced to (perhaps) ~25% of current levels if we chose to do so. A bold statement - but thinking back to a childhood in the 1950s and 1960s:
- only the living room in a 3 bed detached house had heating (coal then gas)
- single glazed throughout - frost on inside of the windows in winter
- no cavity wall insulation - many older properties would have been solid walls
- one central ceiling lamp in each room
- one bathroom not three
- washday one a week, not every day in the automatic washing machine
- clothes worn for several days before washing - before the advent of deodorants
- no tumble dryer - washing lines ruled
- fridges still a rarity. No second freezers in the garage
- blankets on the bed, thermals, woolies (not the shop) etc were standard issue
Technological improvements would make a typical house of the 1950s less challenging - cavity wall insulation, double glazing, led lighting etc.
Energy makes us comfortable - we enjoy its consumption, not the cost. I am not proposing a return to the 1950s, but it was the norm, how most expected to live, not a pit of deprivation.
We are simply profligate with energy because we can afford to be, and we enjoy it!