- A new study from Carnegie Mellon University found federal buildings with an energy efficiency certification managed by the U.S. Green Building Council (USGBC) are not using less energy, potentially due to "trade-offs" in how their energy score is developed.
- The LEED (Leadership in Energy and Environmental Design) program was launched in 1998 by the USGBC, and obtaining that certification is a tool the U.S. General Services Administration (GSA) utilizes in its efforts to save energy.
- USGBC defended the LEED program, pointing to other studies indicating certified buildings are consuming significantly less energy. And, "anecdotally we sometimes hear that renovated green buildings often are used much more than previously," USGBC Senior Policy Counsel Elizabeth Beardsley said in an email.
LEED has been around more than 20 years, is internationally recognized and is "one of the most sought-after" green certifications in the building sector, according to the Carnegie Mellon research. However, the study found LEED has "no effect" on the average energy consumption of federally-owned buildings.
That finding reflects the fact that energy use is just one of a number of attributes examined by the LEED program, and some of those attributes may consume energy, the authors said.
"Buildings with above average energy scores have greater energy efficiency post-certification. Some other attributes, notably higher water scores, decrease energy efficiency post-certification," the study finds. "Trade-offs across LEED attributes account for the absence of energy savings on average. If energy efficiency is the primary policy goal, LEED certification may not be the most effective means to reach that goal."
The study examines 1990-2019 data from GSA's Energy Usage Analysis System and the Green Building Information Gateway to consider the impact of LEED certification on federally-owned buildings.
And while the research includes just federally owned buildings, the authors add that "to the best of our knowledge, however, there is no credible evidence on the effectiveness of green certification programs in reducing energy consumption in commercial buildings."
"Real estate developers may trade off energy savings for other attributes aimed at improving design and comfort in buildings," the paper says.
LEED's lack of an impact on a building's energy use may also be caused by energy consumption from sensors in water-efficient bathrooms and landscaping systems, the authors suggest.
The conclusions "have significant implications for policy," according to Karen Clay, a professor of economics and public policy at Carnegie Mellon's Heinz College.
"As the Biden Administration looks at how best to invest in energy efficiency, they should be sure to design policies that provide the intended incentives," Clay, who led the study, said in a statement.
Some revisions are in the works to the LEED program, Clay said, to increase emphasis on energy usage, but "the inherent tradeoffs are likely to remain."
Beardsley said the GSA "has found distinctly different results in its evaluations of LEED certified buildings."
GSA tracks projects funded under the American Recovery and Reinvestment Act of 2009, and Beardsley said that buildings with completed projects are now 22% more energy efficient than before upgrades. And a 2018 PwC assessment of high-performing federal buildings, "many of them LEED certified," found they used 23% less energy and 28% less water, along with other savings, Beardsley said.
"Each of these resources has associated [greenhouse gas] emissions, so reducing their use can shrink a building's total operational GHG footprint," Beardsley added.
She also said that buildings that are upgraded and LEED-certified may simply be nicer or more accessible and get used more, driving up energy consumption.
"Energy consumption of any building depends on usage, as well as efficiency and weather," Beardsley said. "For example, they may have new programming or features that makes them more attractive than the old building for after-hours events, and for hosting meetings and conferences and the like."