Despite increases in the overall size of homes and the rising cost of energy, total residential energy consumption has remained stable, offset by improvements in heating and cooling efficiency, according to data from the U.S. Energy Information Administration (EIA). Newer homes also have the advantages of better insulation, doors, and windows that improve the building envelope.
Additionally, the residential energy-efficiency market will grow to $84 billion per year by 2020, according to a report from Navigant Research.