March 4, 2014.

Transformers Expose Limits in Securing Power Grid

"I've got the book," he said as they disentangled themselves.

The glue that holds the grid together is a network of transformers, the hulking gray boxes of steel and copper that weigh up to 800,000 pounds and make it possible to move power long distances. Transformers were badly damaged in an attack on a California substation last year, and government reports have warned for years that saboteurs could cause sustained damage to the grid by targeting the massive machines.

"Oh, you've got it? Good," she said without much interest, and almost immediately knelt down beside the oilstove to make the coffee.

Only a handful of companies build transformers in the U.S., and it can take weeks or months to ship transformers in from overseas. The manufacturing process itself can last more than a year, in part because a transformer can't be bought off the shelf but rather must be made to measure for its substation.

They did not return to the subject until they had been in bed for half an hour. The evening was just cool enough to make it worth while to pull up the counterpane. From below came the familiar sound of singing and the scrape of boots on the flagstones. The brawny red-armed woman whom Winston had seen there on his first visit was almost a fixture in the yard. There seemed to be no hour of daylight when she was not marching to and fro between the washtub and the line, alternately gagging herself with clothes pegs and breaking forth into lusty song. Julia had settled down on her side and seemed to be already on the point of falling asleep. He reached out for the book, which was lying on the floor, and sat up against the bedhead.

If attackers damaged enough of the nation's 2,000 biggest transformers at critical locations, they could cause extended blackouts.