The Capitol Power Plant is a fossil-fuel burning power plant which provides

steam Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is inv ...

and

chilled water Chilled water is a commodity often used to cool a building's air and equipment, especially in situations where many individual rooms must be controlled separately, such as a hotel. The chilled water can be supplied by a vendor, such as a public u ...

for the

United States Capitol The United States Capitol, often called the Capitol or the Capitol Building, is the Seat of government, seat of the United States Congress, the United States Congress, legislative branch of the Federal government of the United States, federal g ...

, the

Supreme Court In most legal jurisdictions, a supreme court, also known as a court of last resort, apex court, high (or final) court of appeal, and court of final appeal, is the highest court within the hierarchy of courts. Broadly speaking, the decisions of ...

, the

Library of Congress The Library of Congress (LOC) is a research library in Washington, D.C., serving as the library and research service for the United States Congress and the ''de facto'' national library of the United States. It also administers Copyright law o ...

and 19 other buildings in the Capitol Complex. Located at 25 E St SE in southeast Washington, D.C., the CPP was the only coal-burning power plant in the District of Columbia, and it now mostly uses natural gas. The plant has been serving the Capitol since 1910, and is under the administration of the

Architect of the Capitol The Architect of the Capitol is the Federal government of the United States, federal Government agency, agency responsible for the maintenance, operation, development, and preservation of the United States Capitol Complex. It is an agency of t ...

(see ). According to the

U.S. Department of Energy The United States Department of Energy (DOE) is an executive department of the U.S. federal government that oversees U.S. national energy policy and energy production, the research and development of nuclear power, the military's nuclear we ...

, the facility released 118,851 tons of

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

in 2007. In 2009, it switched to using natural gas, unless coal was needed for backup capacity. Though it was originally built to supply the Capitol complex with

electricity Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

as well, the plant stopped generating electricity in 1951. In 2013, it was announced that the Capitol Power Plant would add a cogeneration plant that will use natural gas in a combustion turbine to efficiently generate both electricity and heat for steam, thus further reducing emissions. A 7.5 megawatt

cogeneration Cogeneration or combined heat and power (CHP) is the use of a heat engine or power station to generate electricity and useful heat at the same time. Cogeneration is a more efficient use of fuel or heat, because otherwise- wasted heat from elec ...

facility was completed at the CPP in 2018. In 2021 it produced 32,000 tons of carbon dioxide.

History

The power plant was constructed under the terms of an

act of Congress An act of Congress is a statute enacted by the United States Congress. Acts may apply only to individual entities (called Public and private bills, private laws), or to the general public (Public and private bills, public laws). For a Bill (law) ...

passed on April 28, 1904, and authorized in order to support two new office buildings that were then being planned. Now known as the

Cannon House Office Building The Cannon House Office Building, often called the "Old House Office Building", completed in 1908, is the oldest office building of the United States Congress in Washington, D.C. A significant example of the Beaux-Arts style of architecture, it ...

and the

Russell Senate Office Building The Russell Senate Office Building is the oldest of the United States Senate office buildings. Designed in the Beaux-Arts architectural style, it was built from 1903 to 1908 and opened in 1909. It was named for former Senator Richard Russel ...

, these new offices required a substantial increase in energy supplied to Capitol Hill. In addition, the U.S. Capitol and the

would also receive power from the new plant, along with all future buildings to be constructed on the Capitol campus. Originally called the "Heating, Lighting, and Power Plant," the Capitol Power Plant was one of the earliest 25 Hz alternating current electric-generating facilities in the United States. The original steam boilers were replaced in 1923. In 1950 the steam boilers were modernized and replaced with coal-fired steam generators; at the same time, the plant's electricity generating capacity had reached its limit, and the decision was made to abandon electricity production in favor of the local electrical utility. The expansion of the plant to support additional new construction was authorized in 1958, 1970, and in the early 21st century to support the opening of the

Capitol Visitor Center The United States Capitol Visitor Center (CVC) is a large underground addition to the United States Capitol complex which serves as a gathering point for up to 4,000 tourists and an expansion space for the U.S. Congress. Senators from coal mining states blocked a proposal in 2000 to use cleaner fuel for the plant. Senators

Mitch McConnell Addison Mitchell McConnell III (; born February 20, 1942) is an American politician and attorney serving as the senior United States senator from Kentucky, a seat he has held since 1985. McConnell is in his seventh Senate term and is the long ...

( Republican of

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

) and

Robert Byrd Robert Carlyle Byrd (born Cornelius Calvin Sale Jr.; November 20, 1917 – June 28, 2010) was an American politician who served as a United States senator from West Virginia for over 51 years, from 1959 until his death in 2010. A Democratic Pa ...

( Democrat of

West Virginia West Virginia is a mountainous U.S. state, state in the Southern United States, Southern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States.The United States Census Bureau, Census Bureau and the Association of American ...

), both from

coal mining Coal mining is the process of resource extraction, extracting coal from the ground or from a mine. Coal is valued for its Energy value of coal, energy content and since the 1880s has been widely used to Electricity generation, generate electr ...

states, used their influence as two of the Senate's most senior members to block this proposal. In May 2007, CNN reported that two companies, International Resources Inc. and the Kanawha Eagle mine, have a contract to supply a combined 40,000 tons of coal to the plant over the next two years. The companies gave a combined $26,300 to the McConnell and Byrd campaigns for the 2006 election. In June 2007,

Speaker of the House The speaker of a deliberative assembly, especially a legislative body, is its presiding officer, or the chair. The title was first used in 1377 in England. Usage The title was first recorded in 1377 to describe the role of Thomas de Hung ...

Nancy Pelosi Nancy Patricia Pelosi ( ; ; born March 26, 1940) is an American politician who was the List of Speakers of the United States House of Representatives, 52nd speaker of the United States House of Representatives, serving from 2007 to 2011 an ...

announced the "Greening the Capitol" initiative. The initiative's goal is to make the Capitol

carbon neutral Global net-zero emissions is reached when greenhouse gas emissions and Greenhouse gas removal, removals due to human activities are in balance. It is often called simply net zero. ''Emissions'' can refer to all greenhouse gases or only carbon diox ...

, and the power plant is a major obstacle to achieving this objective. In November 2007, Daniel Beard, the House's Chief Administrative Officer, announced that he would purchase $89,000 worth of

carbon offset Carbon offsetting is a carbon trading mechanism that enables entities to compensate for offset greenhouse gas emissions by investing in projects that reduce, avoid, or remove emissions elsewhere. When an entity invests in a carbon offsetting ...

s for 30,000 tons of carbon emissions. Beard made the purchase from the Chicago Climate Exchange. On February 28, 2009, Pelosi and

Senate Majority Leader The positions of majority leader and minority leader are held by two United States senators and people of the party leadership of the United States Senate. They serve as chief spokespersons for their respective political parties, holding the ...

Harry Reid Harry Mason Reid Jr. (; December 2, 1939 – December 28, 2021) was an American lawyer and politician who served as a United States Senate, United States senator from Nevada from 1987 to 2017. He led the Senate Democratic Caucus from 2005 to 2 ...

sent a letter to the Architect of the Capitol asking him to create a plan to switch the power plant entirely to natural gas by the end of 2009. This letter came just three days before a March 2009 scheduled protest (which happened despite the change). In response to the letter from Pelosi and Reid, the Architect of the Capitol replied on May 1, 2009 that the plant had been transitioning to natural gas and was prepared to switch completely to that fuel, using coal only as a backup source. In 2008, the plant had operated on about 65% natural gas and 35% coal, compared to 58% coal in 2005. By 2011, coal use at the CPP was down to 5%. In 2013, the Architect of the Capitol announced that it had "identified the construction of a cogeneration plant as the most environmentally and economically beneficial way to meet its goal to use natural gas 100% of the time." The new cogeneration unit would use 100 percent natural gas to provide power for the 23 buildings of the Capitol complex, which includes the Capitol Building, the House and Senate office buildings, the Supreme Court, the U.S. Botanic Garden and the Library of Congress buildings, among others. Not only will it reduce the use of coal on-site for the chillers and boilers, but it would provide 93% of the facility's electricity. This would allow it to replace inefficient, 45% coal-generated electricity bought from the grid with more efficiently generated, on-site electricity that uses no coal. They completed the permitting process for this facility in June 2013.

Emissions

Table 1: Summary of Point Source Emissions: District of Columbia in 2002 (Tons)Base Year 2002 Emissions Inventory Document for Washington, DC-MD-VA Annual PM2.5 NAA_12.14.07, Attachment A1, page 2, "Summary of Point Source Emissions: District of Columbia,"
Metropolitan Washington Council of Governments, Air Quality Files Table 2: Summary of Pollution Reduction at the Capitol Power Plant Following Transition to Natural Gas (Tons)

Particulates

For a plant its size (roughly 1/100 the size of the typical 500 MW power plant), the Capitol Power Plant used to produce a remarkably high quantity of the type of particulate matter (PM2.5) most closely associated with human health effects. As shown in Table 1, in 2002, the plant emitted a full 65 percent of the PM2.5 emitted in the District of Columbia by fixed sources (excluding automobiles, buses, trucks, trains and shipping). With the two other large power plants in the District of Columbia closed, and the CPP transition to cleaner energy, all of the emissions have been significantly reduced. Particle pollution, also called particulate matter or PM, is one of six criteria pollutants (PM, lead, mercury, sulfur dioxide, nitrogen oxide, and ozone) regulated by the

Environmental Protection Agency Environmental Protection Agency may refer to the following government organizations: * Environmental Protection Agency (Queensland), Australia * Environmental Protection Agency (Ghana) * Environmental Protection Agency (Ireland) * Environmenta ...

. PM is a complex mixture of extremely small particles and liquid droplets in the air. When inhaled, these particles can reach the deepest regions of the lungs. Exposure to particle pollution is linked to a variety of significant health problems, ranging from aggravated asthma to premature death in people with heart and lung disease. Particle pollution also is the main cause of visibility impairment in the nation's cities and national parks."PM Standards Revision - 2006,"
U.S. Environmental Protection Agency. Fine particles (PM2.5) are 2.5 micrometers in diameter and smaller; and inhalable coarse particles (PM10) are smaller than 10 micrometers and larger than 2.5 micrometers. In 2006, EPA tightened the 24-hour fine particle standard from 65 micrograms per cubic meter to 35 micrograms per cubic meter, while leaving the annual fine particle unchanged. EPA retained the annual fine particle standard at 15 micrograms per cubic meter. EPA retained the pre-existing 24-hour PM10 standard of 150 micrograms per cubic meter. Due to a lack of evidence linking health problems to long-term exposure to coarse particle pollution, the agency revoked the annual PM10 standard.

References

External links

Capitol Complex Overview

* , Statute for the Capitol Power Plant via the

Cornell Law School Cornell Law School is the law school of Cornell University, a private university, private, Ivy League university in Ithaca, New York. One of the five Ivy League law schools, Cornell Law School offers four degree programs (Juris Doctor, JD, Maste ...

{{CapitolComplex Energy infrastructure completed in 1910 Coal-fired power stations in Washington, D.C.

Power Plant A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the electricity generation, generation of electric power. Power stations are generally connected to an electr ...

Former coal-fired power stations in the United States District heating in the United States District cooling