Most infrared heaters operate on 1500 watts. So the electricity cost to run it for 24 hours can be calculated as 1500 x 24 x 0.13 ÷ 1000 (where division by 1000 is to convert watts to kW and multiplication by 0.13/kWh is the average American electricity rate). This brings the total cost to run an infrared heater to $4.68 per day.