The White House gets its electric power from Pepco, the Potomac Electric Power Company. However Pepco generates its power, that's what the White House is getting.
IIRC, they've got coal-burning plants at Dickerson, Maryland; and Morgantown, Maryland, plus several other plants. The Dickerson plant is served by the Baltimore and Ohio Railroad (B&O), and the Morgantown plant gets its deliveries via a branch of the Pennsylvania Railroad (PRR) that comes down from Bowie, Maryland.
There used to be a power plant serving the Capitol near the Botanic Gardens, and another in Georgetown. The one in Georgetown got coal delivered over the Georgetown Branch of the B&O. The line came down through Montgomery County from Georgetown Junction, about a mile west of Silver Spring.
Here are the answers to whichWMATA week 134
PHOTOGRAPHY By Matt Johnson (Editorial Board Alum) December 13, 2018
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Image 3: Capitol South
The third image shows a simple uncovered Metro escalator shaft surrounded by rowhouses. Several Metro stations are placed in settings like this, but the lack of an escalator canopy, like at Eastern Market, narrows the field a bit. The real clue here is the pair of smokestacks visible in the distance. These serve the
Capitol Power Plant on E Street SE, a block and a half south of the station entrance. While the plant is called a power plant, it actually hasn't supplied electricity to the Capitol complex since 1952. It does provide steam and chilled water to the complex, which includes the Library of Congress, the Supreme Court, and the House and Senate Office Buildings.
There's a power plant at Benning. You almost go over it on the Orange Line to New Carrollton right after the split where the Blue and Silver lines take off in the direction of Largo.