The HEScore tool scores a home on a 10-point scale, where a 10 corresponds to greatest efficiency (minimal energy use). Each point on the scale corresponds to a specific source BTU level. National average source energy factors are used to calculate a total energy value for electricity, natural gas, liquified propane gas, and distillate fuel oil energy sources delivered to the home. The source energy factors are from the Energy Star Portfolio Manager Technical Reference (US EPA, 2013).
a consistent set of upgrade recommendations must be considered for each home (variations in which are recommended as a function of home characteristics, cost-effectiveness, etc.). Upgrades considered in the HEScore tool include improvements to the home envelope and major equipment (the "assets") but not to lighting, appliances, or usage changes. Unlike other Home Energy Saver tools, HEScore applies a fixed, standardized retrofit cost (from the NREL National Residential Efficiency Measures Database) and generates recommendations, providing the highest performance level with a payback time of 10 years or less. Energy savings are those achieved by moving between the existing home and the deemed efficiency level of the upgrade.
HEScore currently provides the following two categories and specific upgrades:
Type 1 - Improvements Recommended Now
These upgrades can help save energy right away:
Type 2 - Recommendations for When You Need to Replace Equipment
These recommendations will help save energy when it is time to replace or upgrade:
It is important to note that the sum of the savings from the individual measures of the recommendations report may not equal the total savings for the package of selected upgrades (the number shown on the label). This difference is due to interactive effects of individual energy improvements. When improvements reduce energy consumption within the same end use (e.g., a window upgrade plus an air conditioner upgrade), the resulting dollar savings is less than the sum of the savings shown for the individual improvements.