The National Archives and Records Administration’s (NARA) combined heat and power (CHP), or cogeneration, system has achieved an operating efficiency of 72%.
Conventional production of electricity and thermal energy can be less than 50% efficient.
The highly efficient system increases the reliability of the D.C. facility’s electricity supply while also reducing carbon pollution, an effort that the EPA has recognized with an ENERGY STAR Combined Heat and Power Award.
Put Wasted Heat to Use
NARA operates a 150 kW CHP system at its National Archives Building, which houses historical documents including the U.S. Constitution, the Bill of Rights, and the Declaration of Independence. By recovering otherwise wasted heat, the system produces all hot water needed by the facility.
Excess hot water helps supply the building’s dehumidification system, which is crucial for protecting the archive’s sensitive documents.
NARA’s CHP system was developed under an energy savings performance contract in which an energy service company (ESCO) pays all costs associated with the installation of energy efficient equipment.
A portion of the annual savings goes to the ESCO during the agreed upon contract term. At the end of the term, all equipment and savings belong to the customer.
Renewable Landfill Gas
The Marine Corps Logistics Base, located in Albany, GA, was also a recipient of the award.
The base is saving $1.3 million annually in energy costs compared to what it had been spending before the installation of its CHP system, which utilizes renewable landfill gas from the nearby Dougherty County Landfill.
In the event of a disruption in the landfill gas supply, the 1.9 mW system can switch to natural gas. According to the EPA, approximately 450 U.S. landfills are candidates for energy production.
An additional benefit is protection against power outages. If the grid goes down, the system is capable of operating independently.