Green Proving Ground: Getting Us to the Leading Edge

GSA’s Green Proving Ground (GPG) program is one of the ways the Federal Government is working to make our buildings more efficient and minimize resource consumption. By leveraging GSA’s real estate portfolio to evaluate emerging building technologies, GPG facilitates and accelerates the adoption of cutting-edge technologies in our Federal buildings towards a more sustainable future. Working with the Department of Energy’s National Laboratories, GPG evaluates technologies in a real-world context in order to recommend deployment strategies towards achieving ambitious energy-saving goals.

Today, GPG is proud to announce the release of three new sets of evaluation results.

Before and after shots of office space with and without daylighting
Using Our Natural Resources: Office lighting conditions with electric lighting (top) and daylighting only (bottom)

Stuck at the office? How you can enjoy more sun…and save more energy!

Too often, office space electric lights are left on during the day, even in areas fully illuminated by sunlight — at 26%, electric lighting accounts for the largest percentage of all electricity used in U.S. commercial office buildings. Daylight harvesting, the use of natural light to offset electric light in perimeter workspaces, offers the opportunity to reduce lighting energy by between 20% and 60%, assuming that daylight harvesting is only one component of an integrated lighting control system. To evaluate the incremental savings from daylight harvesting, GPG assessed the performance of daylight harvesting at five Federal building sites, and found an average annual energy savings of 27% and simple payback as low as four years.

How can wood pellets make heating your building more efficient?

The wood-pellet-fired biomass boiler is a renewable energy technology that powers hot-water-heating systems with solid wood fuel—such as wood pellets, chips, or sawdust—instead of more expensive liquid fuels. In 2012, GPG evaluated a state-of-the-art biomass boiler at the Federal Building in Ketchikan, Alaska. The team found the boiler to be running smoothly with minimal maintenance after a year of operation, at a tested performance level of 85.6% efficiency. The project demonstrated that wood-pellet-fired biomass boiler systems are an efficient alternative for hot-water-heated facilities where natural gas is unavailable.

How can we use recycled steam heat to our buildings?

Heating accounts for roughly a third of total energy consumption in U.S. commercial buildings, with boilers supplying heat to 34% of total floor space. Condensing boilers perform more efficiently than conventional boilers by extracting more of the heat energy released through steam in the combustion process. Expanding upon a May 2013 evaluation conducted in Atlanta, Georgia, GPG assessed the performance of condensing boilers at an additional five buildings in Lakewood, Colorado. All facilities experienced significant reductions in natural gas consumption, with savings over 14% compared with conventional boilers.

Green Proving Ground logo

Find these reports, nine previously released reports, and more information about GSA’s Green Proving Ground program at


Related posts:

  1. Green Proving Ground: Paving the Way for Promising Technologies
  2. Green Proving Ground: Using Technology to Improve Building Performance
  3. Putting Green Technologies to the Test