The Grid: A Journey Through the Heart of Our Electrified World by Phillip F. Schewe. Joseph Henry Press, $27.95, 320 pages.

The Plain Dealer

April 1, 2007


Physicist's electrifying look into American grid reliance

By PHILLIP MANNING

Electricity, says Phillip Schewe, is good for us. Life expectancy and literacy increase as usage rises.
In "The Grid: A Journey Through the Heart of Our Electrified World," physicist and playwright Schewe delivers a comprehensive history of electrical systems around the world. Much "of what we call modernity," he writes, "is fundamentally electrical in nature."
In North America, the electrical grid comprises more than 10,000 power plants and millions of consumers, all connected by hundreds of thousands of miles of wires. Most of our light bulbs, air conditioners, furnaces, television sets and computers suck power from the grid.
Despite the obvious advantages, Schewe frequently harks back to simpler times. The grid may be an inevitability of modern life, but it also means "not quite clear skies, no more Milky Way, and less self-made musical entertainment."
So why have the complicated interconnections of a grid at all? Why doesn't each municipality or even each neighborhood have its own generators? The answer lies in the peculiar nature of electric power. Alternating current electricity cannot be stored. Bigger grids make an imbalance between generated power and demand less likely. It's a matter of averages: If there are only two light bulbs on a circuit, one off and one on, and you turn the second light on, the utility must quickly deliver twice as much electricity. On the other hand, if there are a million light bulbs in the circuit, turning on one more will have no effect.
Unfortunately, the flexibility that the interconnectivity provides comes with a huge downside: A single problem can crash the entire grid. That is exactly what happened Aug. 14, 2003, when millions of homes and offices, from Cleveland to New York City, suddenly lost power. Schewe does a superb job in leading the reader to the source of the problem.
Hot weather coaxed many Ohioans to switch on air conditioners that August day. The added current heated the transmission wires, causing them to expand and sag. A drooping wire encountered a tree limb and short-circuited. The short circuit in Ohio, compounded by operator errors, stranded passengers in elevators in New York and deprived most of the Northeast of refrigeration, rail service and, of course, air conditioning. It was a stunning reminder of how dependent we are on the grid. And just how vulnerable it is to minor disturbances.
Despite occasional blackouts, though, the American grid hums along as a remarkable success. It runs at an efficiency called "three nines," which means that it performs perfectly 99.9 percent of the time. And, as Schewe writes, that "sounds pretty good for any human-built system."
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