Energy Costs

If you know the kWh/year, often referred to household appliances (refrigerators, stoves, washing machines, dishwashers, etc.) sold in stores, use the first formula to calculate the cost of the average annual consumption. Otherwise, if you know the number of watts consumed by a light bulb or anyother appliance, use the second formula by including your prediction for use in time: hours per day, days per month and months per year.