Greenhouse Gas, Energy and Water Conservation

The Department’s Greenhouse Gas, Energy and Water Conservation Program ensures that natural resources are utilized efficiently when designing, constructing, and maintaining its facilities. These Programs are established to meet the requirements of the Energy Policy Act of 1992 (EPAct 1992) and Executive Order (EO) 13693 with a goal to reduce energy by upgrading existing heating, ventilation, and air conditioning (HVAC) systems; incorporating energy-efficient and renewable energy technologies; incorporating water-efficient systems, and is pursuing aggressive energy efficiency projects financed through energy savings performance contracts.  The Department also recognizes the importance of efficiently managing water usage to achieve conservation measures.

Greenhouse Gas Emissions

The primary six greenhoues gases (GHGs) of concern are: carbon dioxide, methane, nitrous oxide, hydrofluoro-carbons, perfluorocarbons, and sulfur hexafluoride. The main sources of these gases due to human activity are as follows:

  • Carbon Dioxide (CO2): burning of fossil fuels and deforestation;
  • Methane (CH4): livestock enteric fermentation (i.e. cows) and manure management, paddy rice farming, land use and wetland changes, pipeline losses, and covered vented landfill emissions;
  • Hydrofluorocarbons (HFCs): these items are of concern from the standpoint of global warming and the Kyoto Protocol;
  • Perfluorocarbons (PFCs): these are being used in refrigerating units as replacements for CFCs;
  • Nitrous Oxide (N2O): this is used for its anesthetic and analgesic effects as well as being used as an oxidizer in rocketry and in motor racing to increase the power output of engines;
  • Sulfur Hexafluoride (SF6): used in the electrical industry as a gaseous dielectric medium for high-voltage (35 kV and above) circuit breakers, switchgear, and other electrical equipment, often referred to as SF6. SF6 is also employed as a contrast agent for ultrasound imaging. See the DOE Safety Bulletin for more information on SF6.

Energy Efficiency

With more rigorous energy reduction requirements included in the Energy Independence and Security Act of 2007 (EISA) and Executive Order (EO) 13693, the Department has incorporated strategies to reduce energy use at its facilities, including comprehensive operations and maintenance (O&M) assessments.

Renewable Energy

In the United States, electricity is generated primarily from the combustion of a limited supply of fossil fuels, or with large hydroelectric dams, or with nuclear power plants. Each of these traditional approaches presents unique environmental concerns. Renewable energy dramatically lowers pollution emissions, reduces environmental health risks, and slows the depletion of finite natural resources.

Renewable energy is derived from sun, wind, water, or the Earth's core. It also can be derived from biomass—or plant matter—which is grown, harvested, and transferred into energy by one of a number of processes. Renewable technologies are designed to capture and store this energy.

They include:

  • Photovoltaic solar panels convert sunlight directly into electricity.
  • Wind turbines capture wind to turn rotors, which turns a generator and creates electricity.
  • Transpired solar collectors use sunlight to preheat air for heating purposes.
  • Solar hot water heaters use the sun to heat water for domestic applications.
  • Small-scale hydroelectric power plants flow water over turbines, which turn a generator and create electricity.
  • Fuel cells combine hydrogen and oxygen to produce electricity and heat.
  • Ground source heat pumps transfer heat to the ground in summer and extract heat from the ground in winter.
  • Green power is electricity generated from renewable sources such as wind, geothermal, biomass, and landfill gas.

Alternative Financing

The federal government spends billions of dollars on energy costs each year, and financing large-scale projects can be prohibitively expensive for a federal agency. There are several approved ways to finance such large projects:

  • Energy Savings Performance Contracts (ESPCs)
  • Utility Energy Service Contracts (UESCs)
  • Power Purchase Agreements
  • Energy Incentive Programs

Energy Savings Performance Contracts —Congress authorized ESPCs to encourage federal agencies to become more energy-efficient and to reduce their energy costs. ESPCs enable agencies to improve energy efficiency—reducing energy use and costs—through private investments. An ESPC is an agreement between a federal facility and an Energy Services Company (ESCO). The ESCO designs a project to increase the energy efficiency at a facility. The ESCO then purchases and installs the necessary equipment, such as new energy-efficient windows, automated controls, and updated heating, ventilation, and air conditioning equipment. In exchange for not having to pay for the equipment, the federal agency promises to pay the company a share of the savings resulting from the energy efficiency improvements. The ESCO is responsible for maintaining the equipment, as well as measuring the energy consumption and savings.

Utility Energy Service Contracts —UESCs offer Federal agencies an effective means to implement energy efficiency, renewable energy, and water efficiency projects. In a UESC, a utility arranges funding to cover the capital costs of the project, which are repaid over the contract term from cost savings generated by the energy efficiency measures. With this arrangement, agencies can implement energy improvements with no initial capital investment. The net cost to the Federal agency is minimal, and the agency saves time and resources by using the one-stop shopping provided by the utility.

Power Purchase Agreements—PPAs allow Federal agencies to fund on-site renewable energy projects with no up-front capital costs incurred. With a PPA, a developer installs a renewable energy system on agency property under an agreement that the agency will purchase the power generated by the system. The agency pays for the system through these power payments over the life of the contract. After installation, the developer owns, operates, and maintains the system for the life of the contract.

Energy Incentive Programs—Most states have energy incentive programs that help offset energy costs while promoting energy efficiency and renewable energy technologies. Federal Energy Management Program (FEMP) researches these programs on a state-by-state basis to help Federal agencies meet their energy management goals.
More information on alternative financing can be found on the FEMP Project Funding website.

Water Management

With the U.S. population doubling over the past 50 years, our thirst for water tripling, and at least 36 states facing water shortages by 2013, the need to conserve water is becoming more and more critical.  In recognition of these factors, the Department is committed to responsibly managing water resources by integrating water management best practices at its facilities.  

The Department’s approach to water conservation is driven by federal water efficiency requirements. To meet its requirements, the Department has developed strategies, which guide the water conservation-related actions the Department takes. These actions lead to projects that reduce water use and intensity at the Agency's facilities. Review the sections outlined below for more information.

Federal Requirements and Best Management Practices. Examine the federal laws and regulations that require federal agencies to reduce water use and improve water efficiency, as well as explore federal water efficiency best management practices.

Office of Facilities and Environmental Quality
Office of the Chief Financial Officer and Assistant Secretary for Administration
U.S. Department of Commerce

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Page last updated:November 1, 2016