How much does the energy cost to run a light bulb?
If you know the wattage and price of your electricity then you can figure out the cost over time with this formula: Energy Cost to run = wattage x cost per kilowatt hour x average rated life 1000 Note the cost per kilowatt hour is available from your utility. For example, the cost to run a 100 watt lamp with an average rated life of 750 hours at a rate of .10/kWh would be: Cost = 100 x .10 x 750 which works out to be $7.50.
