Question: what formula is used to find watt-hours?
Answer: Divide the number of watts by 1000 to convert the number from watts to kilowatts. 60W divided by 1000 results in 0.06kW. Multiply the number of kilowatts by the number of hours the device will be used. If the device will be used for three hours, multiply 0.06kW by three to produce 0.18kWh.