Skip to main content

How is Energy Efficiency Measured?

If you’ve read my previous posts on the origin of Passive House, you’ll know it originated out of Europe and the Passive House standards were born of the Low Energy House standards.

The chart below references European homes and is in kWh per square meters per year, but you can imagine use patterns are not extremely dissimilar in the U.S. On the other hand, since we are notoriously heavy energy consumers, the energy savings indicated would be that much more graphic!

  • Energy efficiency ratings of cars are measured in miles per gallons. Homes are rated for energy efficiency in Kilowatt hours per square foot per year. (KWh / ft² / yr).
  • The chart below breaks up energy consumption of homes in different categories, including space heating (red), warm water (blue), electricity (yellow) and electricity for ventilation (white).
  • The four bars (from left to right) compare existing buildings built according to old European codes, existing buildings built according to current European codes, low energy buildings of the 1980′s and current Passive homes. The higher the bar, the more energy the building consumes per square foot per year.

*reprinted from Bau Technologies

The Artisans Group designs and builds to Passive House standards. Our lead designer, Tessa Smith, is a certified Passive House Consultant, one of less than 300 in the nation at the time of this writing.