LEED and Living Buildings are holistic rating systems. There are a number or energy-only rating systems in the U.S. The following is a sampling of a few of them.
Energy Use Index (EUI) and Benchmarking are very common metrics in the energy management industry and energy policy world. They focus solely on energy use, and are relatively simple ways to assess and influence the energy efficiency of buildings.
First, read the following short reading about Energy Use Index (sometimes called "Energy Use Intensity") and watch the video below.
Benchmarking is a common practice in the commercial energy efficiency industry. The most commonly used software for this is Portfolio Manager from the U.S. Environmental Protection Agency (EPA). Read the summary of both of these below
An energy use index (EUI) is relatively easy to determine. You just take a year's worth of energy bills, convert the total energy use to kBTU (thousands of BTUs), then divide by square footage. That's it! This gives you a snapshot of the general energy efficiency of a building, though not a comprehensive one. It is a helpful basis of comparison for other buildings, which is exactly what EPA Portfolio Manager does. Portfolio Manager compares your building's EUI with other similar buildings. What is meant by "similar?" Well, that depends on a few factors, but the most important aspects are 1) buildings in a similar climate zone and 2) buildings that are used for similar things. For example, the mean EUI of an education building in the U.S. is 51 kBTU/ft2, while the mean EUI of a hospital is about 188 kBTU/ft2 (source: Lawrence Berkley National Laboratory Buildings Performance Database [3]). Why the difference? Think about the difference in operating hours and equipment used in these buildings. Given this, it would be unfair to compare the "typical" energy use of a hospital with the "typcial" energy use of a college or middle school. Similarly, you would expect slightly different energy use based on the climate. The exact same building in a temperate climate such as, say, Coastal North Carolina would use less energy than one in a cold climate such as Minnesota or Maine or a hot, humid climate such as Florida.
EPA provides you with an "Energy Score" based on other buildings in their database. A score of 25 means you have a lower EUI than 25% of comparable buildings, a score of 50 means you have a lower EUI than 50% and higher than 50%; a 90 means you have a lower EUI than 90% of buildilngs, and so on. EPA provides the option of being Energy Star rated if you have a score of 75 or above. Some municipalities (such as Philadelphia [4]) require buildings to obtain their Energy Score every year so that they may constantly see how they compare to other buildings. The benefit of doing this every year is that you are forced to keep up with your peer buililngs. Let's say you get a score of 75, then think: "Cool, I'm very efficient. I don't need to make any upgrades." But then if other buildings become more efficient over time, your score will drop. In this way, the process of improving efficiency in theory never ends.
Energy Star is a program created and run by the U.S. Environmental Protection Agency (EPA). As the name implies, this is an energy efficiency rating system that has the following four components:
a high efficiency thermal enclosure system (thermal envelope!)
According to the EPA [5], Energy Star certified homes "are at least 10% more efficient than homes built to code and achieve a 20% improvement on average." Please read the following summary of the Energy Star Residential New Construction Program:
Here is a great video that introduces some of the benefits of Energy Star Homes. It is geared towards builders but is a helpful introduction for anyone.
OPTIONAL
Passive House Certification is effectively a more robust version of Energy Star Certification. There are actually two different certifying bodies in the U.S. - Passive House Institute (PHI) and Passive House Institute U.S. (PHIUS) - as detailed by ecohome here [8]. The distinction is not important for our purposes, but we will focus on PHIUS standards. The image below provides a sense of how robust Passive House standards are relative to Energy Star and other standards. See this [9] document for a fuller explanation.
Please read the overview below and click on the second link to look at some of the differences between PHIUS and other energy efficiency standards:
The following is a summary of the energy-only rating systems:
Benchmarking:
Energy Star Certification
Passive House Certification
Links
[1] https://www.energystar.gov/buildings/facility-owners-and-managers/existing-buildings/use-portfolio-manager/understand-metrics/what-energy
[2] https://www.energystar.gov/buildings/facility-owners-and-managers/existing-buildings/use-portfolio-manager/learn-how-portfolio-manager
[3] https://bpd.lbl.gov/
[4] https://www.phillybuildingbenchmarking.com/
[5] https://www.energystar.gov/partner_resources/residential_new/about
[6] https://www.energystar.gov/partner_resources/residential_new/homes_prog_reqs/national_page
[7] https://www.energystar.gov/sites/default/files/National%20Program%20Requirements%20Version%203.1_Rev%2011.pdf
[8] https://www.ecohome.net/guides/2191/everything-you-need-to-know-about-passive-house/
[9] https://www.energy.gov/sites/default/files/2017/02/f34/PHIUS%2B2015 Passive Building Standards.pdf
[10] https://www.phius.org/phius-certification-for-buildings-products/project-certification/overview
[11] http://energy.gov/eere/buildings/downloads/phius-information