Find the expensive plugs without guessing.
Power, runtime and price are enough to make an initial estimate. The useful part is making those inputs reflect how an appliance really operates.
Watts describe power, kWh describe energy
A 1,000-watt device running continuously for one hour uses one kilowatt-hour. At 0.15 currency units per kWh, that hour costs 0.15 in energy charges. Runtime changes the result just as directly as wattage.
Allow for cycling
A refrigerator, heat pump or thermostat-controlled heater does not necessarily draw its rated power continuously. Use measured energy over a representative period, or a reasonable average power draw, rather than maximum rated watts for every hour.
Look at standby separately
A small load operating for many hours can add up. Measure groups of electronics with a suitable energy meter. Never disconnect equipment that requires uninterrupted power for safety or health.
Compare before replacing
Enter the current device and a proposed alternative using the same service and runtime. Energy savings are only one part of a replacement decision; include purchase cost, expected life and maintenance when deciding what is worthwhile.
Put the idea into numbers.
Open the calculatorHAUSE Energy · Reviewed September 8, 2026. For current program rules or prices, use your utility’s published documents and the regional source guide.