Metropolitan Washington Airports Authority spokeswoman Courtney Mickalonis says the power went out at about 12:30 p.m and came back on at 1:30 p.m.
Flights were grounded during that period, but the Transportation Security Administration was able to quickly resume screening using a backup generator at two of four checkpoints.
Mickalonis says delays will likely persist throughout the afternoon, so people should check with their airline before heading to the airport to catch a flight.
