Results

Buildings account for about 40% of total energy use and 75% of electricity use in the U.S.— more than the industrial or transportation sectors(National Laboratory of the Rockies, 2026). This is likely to increase in coming years, as commercial data centers are rapidly growing to support AI computing and are projected to account for up to 12% of total U.S. electricity consumption by 2028. Reducing the energy use of our buildings has many benefits:

• Minimizing costs (and saving taxpayer dollars, for government buildings)
• Mission assurance, continuity of services, and facility flexibility and durability, e.g. through smart building technologies
• Improved reliability and longevity of the electric grid
• Promoting American energy independence
• Supporting innovative American-made technologies
• Cleaner air and water and healthier communities

GSA continually invests to maximize the energy efficiency of its buildings, which saves money both on monthly utility bills and by reducing the size and cost of equipment. Opportunities for increasing building efficiency include upgrading equipment and energy management systems, testing and tuning equipment and systems (commissioning), and applying modern high-performance building design practices.

Energy Data Results

FY 2023–2024 energy consumption data for each building in the analysis was converted to British Thermal Units (Btu), then expressed in terms of energy use intensity (EUI), or average consumption per gross square foot per year. The results indicate that GSA’s high-performance buildings are more energy efficient than both legacy stock buildings and commercial office building counterparts. Figure 8 describes the building set included in the results for the energy measure.

Specifically, over a two-year average:

High-performance buildings’ EUI was 21% lower than GSA’s legacy stock buildings High-performance buildings’ EUI was 27% lower than the CBECS benchmark Legacy stock buildings’ EUI was 7% lower than the CBECS benchmark The average EUI of GSA’s high-performance buildings is 47.85 kBtu/GSF, while the average EUI of GSA’s legacy stock buildings is 60.61 kBTU/GSF. If an average-sized legacy stock building were as energy efficient as GSA’s high-performance buildings, one building alone would save 3.3 billion Btus annually. This is equivalent to the annual energy usage of 43 average American homes, and could save taxpayers on average over $120,000 per building per year. If all of GSA’s legacy stock buildings in this study operated as efficiently as our high-performance buildings, energy savings alone would add up to over $21 million per year based on GSA’s national average energy costs.

The federal government collectively spent almost $700 million in FY24 on water and sewer services for buildings. Implementing water conservation measures is a growing priority, due to increasing water demand and regional scarcity, and rising costs of water. Building-related water efficiency efforts seek to reduce water consumption and related expenses without sacrificing water quality, occupant needs, or building performance. Building water use includes both indoor water use, such as plumbing fixtures and large building mechanical equipment such as evaporative cooling towers, as well as outdoor water use, such as irrigation systems. The Environmental Protection Agency’s “WaterSense at Work” publications compile many best management practices for saving water and money in government, commercial, and institutional buildings. Saving water has many benefits: Minimizing water and sewer costs (and saving taxpayer dollars, in the case of government buildings) Reducing energy needed to treat, pump, heat, and/or cool water in buildings Reducing costs and stress on sewer and water treatment infrastructure Reducing the impacts of drought and water scarcity, while freeing up more water for other users, including American farmers, homes, streams, and wetland ecosystems. Paying close attention to water usage patterns and trends may reveal infrastructure problems such as faulty equipment Water Data Results Water use for each building is represented as water use intensity (WUI), calculated as the total gallons consumed per gross square foot of space. These results demonstrate that GSA’s high-performance buildings are more water efficient than both GSA’s legacy stock buildings and average commercial office buildings. Specifically, results show that over a two-year average: High-performance buildings’ WUI was 29% lower than GSA’s legacy stock buildings High-performance buildings’ WUI was 38% lower than the ENERGY STAR® Portfolio Manager 2023 (Portfolio Manager) office building median GSA’s legacy stock buildings’ WUI was 13% lower than the Portfolio Manager median High-performance buildings used 3.4 fewer gallons per gross square foot per year than legacy stock buildings Based on these findings, if a hypothetical average-sized legacy stock building were as water-efficient as GSA’s high-performance buildings, one building alone would save 620,000 gallons annually compared to a legacy stock baseline — almost enough to fill an olympic-size swimming pool. Water cost savings opportunities could exceed $3 million per year if all legacy stock buildings included in this study were to match the WUI of GSA’s high-performance buildings.

Key strategies for reducing energy use and cost related to lighting are:

• Only light what you need to light, when necessary, at the lowest necessary lighting intensity.
• Maximize the use of daylight for basic ambient light levels while providing occupants with additional lighting options to meet their needs.
• Consider circadian light and lighting impacts on human health. Install dimmable lights to allow for reduced lighting levels when sufficient daylight is available.
• Ensure that lighting operating schedules and lighting control systems are set to turn lights off when space is unoccupied.
• Perform a basic lighting study to see if fixtures or lamps can be reduced.
• LED lighting technology offers high-quality light with the highest efficiency of any light-source technology. When upgrading lighting systems, ensure the most efficient LEDs are used while also considering light distribution and light temperature.

Learn more about lighting strategies and other efficiency measures you can implement by reviewing Better Building Initiative’s efficient technologies.

Plug loads refer to energy used by equipment that is plugged into an outlet. In an office, key plug loads include computers and monitors, printers, and copiers. Plug loads can average approximately 30% of electricity use in office settings, much of which can be attributed to parasitic loads (or the power draw of a plug-load that is not performing useful work). Plug loads as a share of overall building energy use is higher in energy efficient buildings. In minimally code-compliant office buildings, plug loads may account for up to 25% of total energy consumption. But in high efficiency buildings, plug loads may account for more than 50% of the total energy consumption. Strategies for reducing energy consumption from plug loads include:

• Specify ENERGY STAR certified appliances and Electronic Product Environmental Assessment Tool or EPEAT-registered equipment.
• Ensure that power management features on computers, monitors, printers, copiers, and conference room technology are enabled.
• Encourage occupants to power down equipment when not in use.