More than 7,500 supermarkets—encompassing 51% of all floor space in the market—currently measure and track their energy performance using EPA’s Energy Star Portfolio Manager tool. On Aug. 27, they—along with hundreds of thousands of other buildings across the country—will see a change in their 1-100 Energy Star score and other metrics. That’s because EPA is updating its energy performance metrics based on the most recent market data available.
How this change will affect grocery stores?
The 1-100 Energy Star score compares a store’s energy performance to that of similar grocery stores nationwide. The most recent market data available shows an overall improvement in the energy performance of U.S. grocery stores and supermarkets in recent years. So when Portfolio Manager metrics are updated on Aug. 27, Energy Star scores and other performance metrics for grocery stores will, on average, go down.
Exact score changes for specific buildings will vary, but we’ve estimated that, on average, grocery stores will see a 1-point decrease in their 1-100 Energy Star scores. But this is an average and an estimate: Each grocery store’s Energy Star score may increase or decrease depending on its energy use, fuel mix, business activity, property type and other variables.
Metrics for new grocery-store designs will also be affected
Note that Energy Star Portfolio Manager and Target Finder also generate metrics used to evaluate energy design targets of new construction projects, including the 1-100 Energy Star score. Both tools calculate metrics using the same underlying methodology, so design metrics are also getting a refresh.
Why this change is happening
Energy Star score models are based on the most recently available data. Until now, the most recent data set we had was the 2003 Commercial Buildings Energy Consumption Survey, put out by the U.S. Department of Energy. Now that the agency has made 2012 survey data available, we’re updating our models to reflect it. EPA’s basic approach is not changing: We still provide a national level benchmark, based on source energy, that normalizes for weather and business activity, and does not factor in technology choices.
Typically, these updates happen somewhat gradually (typically every four years). However, with a nine-year gap between available survey data releases, this round of updates may have a more pronounced effect.
Source energy factors are also changing
Our metrics are based on source energy, or the total primary fuel needed to deliver heat and electricity to a building. Source energy accounts for losses that occur in the distribution, storage, transmission and dispensing of the fuel. (For example, for every one unit of electricity a grocery store uses on-site, a power plant must generate three units, since two units are lost during transmission.)
We’re updating our source electric factor to be slightly lower, based on the new national average. Each grocery store will be impacted differently, depending on its particular fuel-mix, though we expect these changes to be quite small in magnitude.
How to prepare
If you think you’ll need to document changes, download reports before Aug. 26, because all your current and historical metrics will be updated. We suggest two reports at a minimum: “Performance Highlight” report (for a portfolio-level, multiyear summary) and “Statement of Energy Performance” (for a building-level, 12-month performance period). Instructions are on our website.
We also have lots of helpful information, tips and resources for grocery stores on our website at www.energystar.gov/scoreupdates. There, you can also register for an informational webinar to learn more.
Leslie Cook is national program manager for EPA’s Energy Star program for commercial buildings and industrial plants.