Question: how much energy is used to heat water?
Answer: The typical heating range will be taken to be from 60 °F to 140 °F (15.6 °C to 60 °C). The energy required to heat the water can be determined from the specific heat relationship. Since a kilowatt-hour is 3.6 million Joules, this energy amounts to about 7.5 kWh of electricity.