Electricity usage is usually measured in kilowatt-hours (kWh), shown on your bill as the amount of energy used between meter readings. An appliance’s usage depends on its power rating, measured in kilowatts, and how long it runs—for example, a 2 kW heater used for three hours uses about 6 kWh. Heating and cooling, hot-water systems, pool pumps, ovens and clothes dryers commonly use substantial electricity, while lights and small electronics generally use less. Compare meter readings and check your retailer’s bill breakdown, or use the Australian Government’s energy.gov.au guidance to estimate appliance costs.