A brief power outage darkened large parts of New York City on Wednesday, knocking out traffic lights, cutting subway service and forcing the evacuation of the Metropolitan Museum of Art on one of the hottest days of the year. Power was restored within about an hour, but not before traffics lights up and down the east side of Manhattan and the Bronx went out, and subway and train service was snarled all over the city, which consumes more power on a hot summer day than the entire nation of Chile Consolidated Edison spokesman Chris Olert said the outage began at 3:42 p.m. (1942 GMT) and all power was restored by 4:30 p.m. (2030 GMT). The cause was under investigation, with lightning a possibility, Olert said. The Con Edison utility said the blackout affected 136,700 customers, or more than 500,000 people. A customer can consist of a single-family home or an entire apartment building, so one customer often translates into four people.