APPLIANCE COSTS
Space Heater Electricity Use by Hour, Day and Month
Calculate space-heater kWh and cost by hour, day and month using wattage, runtime and your electricity rate.
A 1,500-watt space heater uses 1.5 kWh for each full hour its heating element is on. Multiply 1.5 by operating hours and your electricity rate. At $0.17/kWh, full-power operation costs about $0.26 per hour, $2.04 for eight hours and $61.20 for 30 eight-hour days.
- ✓ Watts ÷ 1,000 × hours = kWh
- ✓ Thermostat cycling may reduce actual consumption
- ✓ Every resistance heater delivers similar heat per watt
Calculate hourly and monthly cost
Find the heater’s wattage label, divide by 1,000 and multiply by hours. Then multiply kWh by your all-in rate. A 750-watt setting uses half the energy of 1,500 watts while it is actively heating.
Understand thermostat cycling
Once a room reaches its setting, the heater may switch on and off. Insulation, drafts, room size and outdoor temperature determine the duty cycle. A plug-in energy monitor provides a better multi-day estimate.
- Measure over representative cold days
- Close drafts before raising the setting
- Heat occupied space only when appropriate
- Compare with the cost and efficiency of the main heating system
Operate the heater safely
Follow the product’s clearance and supervision instructions, place it on a stable surface and plug it directly into a suitable wall outlet. Stop using damaged cords or overheating outlets and never compromise safety for a small energy saving.
Actual energy use and product performance vary by equipment, conditions and installation. Confirm measurements and manufacturer specifications. Qualified professionals should handle permanent wiring and transfer equipment.