Three Transformers to Bring New Power to Ground Zero

Three electrical transformers were lowered by crane into cavernous vaults beneath what will once again become 7 World Trade Center. The transformers, each nearly 85 tons and 20 feet tall, are the first of 10 transformers that will be placed beneath 7 World Trade Center in the next few years, said Michael Clendenin, a spokesman for Con Edison.

Transformers take electricity from high-voltage power lines and reduce its potency in order to route it safely to residential and commercial buildings, Mr. Clendenin said. The transformers are not expected to go into full use until next summer, he explained, as utility workers connect them to local power wires and cables.

Many residents and businesses in Lower Manhattan lost electrical power for more than a week after the terrorist attack as emergency workers sought to dig out the substations from the rubble of 7 World Trade Center. To bring power to the neighborhood, Con Edison laid nearly 36 miles of cables to connect the area to working substations, a process that Mr. Clendenin compared to using "one big extension cord."

At first, these cables were above ground, he said. Eventually, they were buried. The new transformers, which are the working heart of an electrical substation, will replace this jury-rigged system, Mr. Clendenin said.

Perhaps more important, he said, the transformers will supply the power needed for the vast reconstruction of ground zero. "As the buildings of the trade center start to rise," Mr. Clendenin said, "these substations will power that."

He said the rebuilt substations would also be able to provide electricity if demand for it grew in other parts of Lower Manhattan.

The transformers had been stored for some time inside a warehouse in Astoria, Queens. On Friday night, they were loaded onto barges and shipped down the East River around the southern tip of Manhattan to a West Side pier. There, the transformers were loaded onto tractor-trailers, each 100 feet long, and trucked to the construction site.

They were placed into the underground vaults by enormous cranes, Mr. Clendenin said. "You're talking about big, big units."