POWER PLANT:
100 years of continuous service
Stephen T. Ayers, AIA, LEED AP, Architect of the Capitol; Mark D. Weiss, PE, Director, U.S. Capitol Power Plant
Through Prohibition, two world wars, the civil rights movement, “Snowmageddon,” even an earthquake – as Congress debated
the issues of the day – the U.S. Capitol Power
Plant in Washington, D.C., has continued to
provide congressional facilities with thermal
energy for more than 100 years.
In 1904, the United States Congress authorized the construction
of a heating, lighting and power plant to provide services to the few
congressional facilities on Capitol Hill: the U.S. Capitol Building, the
Library of Congress and a new office building being constructed for
the House of Representatives. By 1910, the Capitol Power Plant was
providing steam and electricity to its customers.
News reports at the time of the plant’s commissioning in March 1910
noted that “the plant itself is an unimpressive-looking light brick and stone
building,” but what that anonymous reporter wrote next still stands true
today: “An important item is the enormous savings it would effect in the
items of heating and lighting the big buildings on Capitol Hill.”
Elliott Woods, superintendent of the Capitol (1902-23), was respon-
sible for constructing the facility, and if he were to see the Capitol Power
The Capitol Power Plant was built near railroad
tracks for convenience. (Note the Capitol dome
in the background.)
From 1936 to 1938, the Capitol Power Plant
constructed the refrigeration plant to provide
congressional office buildings with chilled water.
Courtesy Architect of the Capitol.
The Capitol Power Plant, as it appeared when it
was commissioned in 1910. Described then as
an “unimpressive-looking light brick and stone
building,” it is recognized as a modern, efficient
source of steam and chilled water for Congress.
Courtesy Architect of the Capitol.
Courtesy Architect of the Capitol.
