Energy efficiency ratings not reflecting true energy use

Recent findings from the Better Buildings Partnership raise serious questions about the efficacy of energy efficiency ratings used in the United Kingdom.

The study found that buildings that have received the highest rating—an A Energy Performance Certificate—use more energy than some of their peers rated C, D, E, or F. The analysis of self-reported energy data in 2020 for more than 1,100 commercial properties found that the median energy intensity for all B-rated buildings is higher than for C-rated buildings.

The disparity between how buildings are designed and their actual greenhouse gas emissions is widespread in the U.K. The findings are in line with past evidence that green building certifications based on predicted energy use don’t necessarily translate to energy savings in the field.

Some studies have found that LEED certification yields better energy efficiency, but others have found that certified buildings use more energy than non-certified buildings. The U.S. Green Building Council maintains that its own research shows certified buildings are overall more efficient.

Part of the explanation for the disparity between ratings systems and real-world results could be due to the limitation of assessments that only predict potential energy efficiency. In practice, building management systems may not be set up or used properly. In addition, people sometimes undo the efficiency design by bringing fans into buildings or installing additional air conditioners.