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What's New

Cogeneration at the Capitol Power Plant

View of the Capitol Power Plant from House parks.

At the Capitol Power Plant we are planning for the future. Through rigorous analysis of various energy technologies and broad consultation with leading experts, we have explored options for achieving future energy savings, reducing environmental impacts and maintaining a reliable source of chilled water and steam for the 23 facilities on Capitol Hill we serve, including the U.S. Capitol, the Library of Congress and the Supreme Court of the United States. We have identified cogeneration as the preferred solution for our energy future.

What is cogeneration?

Cogeneration, also known as combined heat and power, is a proven technology with more than 4,400 facilities throughout the United States. Using a single fuel source, cogeneration simultaneously produces electricity and heat. The Capitol Power Plant's cogeneration system will use natural gas in a combustion turbine to generate electricity and heat, increasing system reliability, improving efficiency and saving taxpayer dollars.

Why make a change now?

The Capitol Power Plant began operating in 1910 and nearly half of the installed steam capacity comes from old coal-fired boilers dating back to the 1950s. Well past their expected lifespan, the boilers experience frequent breakdowns and failures. CPP mechanics must salvage for spare parts wherever they can find them, as many of the original manufacturers are no longer in business, and the risks associated with trying to maintain this antiquated equipment continue to grow.

To ensure that the Capitol Power Plant is able to meet steam demand at its peak, and that it upholds its mission to provide heat to congressional buildings 365 days a year, 24 hours a day, the Architect of the Capitol will use cogeneration to address the serious and urgent need to replace the failing boilers.

What are the benefits of cogeneration?

Cogeneration technology is a reliable, cost-effective, energy-efficient and environmentally friendly solution. Since 2007, the Capitol Power Plant has steadily increased its reliance on natural gas as its primary fuel source. While coal usage has been reduced, it cannot cease completely until cogeneration is constructed.

By producing steam and electricity together, the cogeneration plant would reduce emissions of greenhouse gases by 6.5% and would reduce emissions of hazardous air pollutants by 18 percent. These benefits reach beyond the Capitol campus and will help improve the regional air quality in the District of Columbia.

Is cogeneration a proven technology?

A broad range of technical and operational options were considered and, with the assistance of the National Academy of Sciences, the Architect of the Capitol selected cogeneration as the best option for modernizing the Capitol campus. The project life cycle cost and business case were further validated using key industry best practices and independently reviewed by the Department of Energy, National Renewable Energy Laboratory (NREL).

Several government organizations and public entities, most notably the Department of Energy and the Environmental Protection Agency (EPA), recognize the benefits of cogeneration in providing reliable, clean and efficient energy. For many years, the EPA has worked with private and public organizations to promote cogeneration through their Combined Heat and Power Partnership program.

Cogeneration facilities in the District of Columbia region, include the General Services Administration, National Institutes of Health, Johns Hopkins University and the University of Maryland.

Capitol Power Plant
Capitol Power Plant
Energy Conservation
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