In another thread I was laughing about how U.S. utilities charge for electricity by the kilowatt hour, but charge for piped natural gas by the "therm," which is 100,000 BTUs. BTUs are the energy required to raise 1 pound of water by 1 degree Fahrenheit, like a shitty imperial calorie.

Confusingly, most gas appliances are marketed as being a certain number of BTUs per hour, but people often omit the implied "per hour" when talking about them, and will talk of their 12,000 BTU stove burner or 30,000 BTU water heater.

Talking through residential energy use without having a solid command of what unit means what would be confusing.