This page describes how the Energy Estimates generated by the Home Energy Saver enegy calculations are use to estimate cost estimates.
The basic calculation of energy bills is given in the following equation:
Annual Cost = Annual site energy * utility conversion[resource] * price[resource]
Where resource is one of electricity ,natural gas ,fuel oil, or lpg
The site units and conversion factors are given in table 1.
When a building is first created default energy prices are assigned based on the state in which their ZIP code is located. The defaults energy prices are presented in table 2 below. Users have the option of overriding these values with their own utility rates. The default energy prices are the most recent available state averages from either 2009 (for electricity and natural gas) or 2007 (for LPG and fuel oil). Energy price data are from the U.S. DOE's Energy Information Administration (US DOE 2007, 2009a, 2009b, 2011), and U. S. EPA 2009, 2012.