Our appliance and electronic energy use calculator allows you to estimate your annual energy use and cost to operate specific products. The wattage values provided are samples only; actual wattage of products varies depending on product age and features. Enter a wattage value for your own product for the most accurate estimate. Wattage and utility rate data sources: 2010 Buildings Energy Databook, Table 2.1.16; Home Energy Saver; EIA Average Retail Price of Electricity - Residential.