The heat is on electric suppliers

In many areas of the eastern United States, including Central Pennsylvania, the demand for electricity in the summer is dangerously close to outstripping supply.

The strains are most evident on hot days when air conditioners across the region are cranked to maximum cool.

A taste of what's

Some large generators were out of service and undergoing routine maintenance at the time. But surnmerlike heat also played a role, as actual summer heat did last year.

The problem is relatively new for Central Pennsylvania. PPL Corp., Allentown, which serves much of the region, has traditionally seen demand go higher in winter than in summer.

But, noted spokesman John Drexler, "Those two peaks are starting to even out."

A thin cushion

Central Pennsylvania boasts nearly 58,000 megawatts of capacity. Last summer on July 6, the grid carried a load of 51,600 megawatts, a record peak that was not expected until 2002.

A July heat storm was largely to blame.

"The weather was much hotter than anyone expected," said Melissa Josef, a spokeswoman for the PJM Interconnection, Norristown. A nonprofit that oversees the grid, the PIM is owned by its 170 members, a group that includes utilities, energy marketers and others.

The PJM had projected the peak last summer would be 49,807 megawatts.

This summer, the grid is bracing for a peak of 51,161 megawatts. The weather is again the main variable, Josef said.

But economic growth and the increasing dependence on computers have also fueled the demand for power.

While a cushion exists between the need for electricity and total supply, it's not very comfortable.

Central Pennsylvania didn't suffer the heat-related outages that hit the Delmarva Peninsula and New York City last summer.

But as it did on May 9 and 10, the region came perilously close on two days last year, July 6 and July 19, according to a report from the U.S. Department of Energy.

On both days, the power grid serving Central Pennsylvania "experienced sudden and steep voltage declines," said the DOE report, which reviewed last year's difficulties.

The declines resulted from stress on power lines caused by the heavy and unexpected demand for power. The voltage drops have forced utilities here to ask customers to voluntarily curtail power use or take other emergency measures to lower demand.

The PJM has acknowledged the need for more supply, and is working to bring more power on-line.

Similar efforts are under way at PPL Corp.

Citing forecasts for a cooler summer, Drexler said there should be no problems this year.

And for the future, he pointed out, PPL is building a 500megawatt natural gas-fired plant in Northampton County, north of Easton. It's expected to begin operating in 2002.

But much of the new, large power plants will arrive too late for this summer.

"I don't know that there's that much additional that's been built" since last summer's emergencies, said Howard Faibus, a former DOE official who is now doing research for Electrotek Concepts Inc., an industry consulting firm based in Arlington, Va.

That's why experts are looking at smaller producers, like the backup generators. at Sight & Sound Theatres in Strasburg.

Tapping the thousands of similar generators in the PJM could have helped to ease last summer's crunch and could forestall difficulties this summer, Faibus said, And the generators' proximity to electricity customers, he added, puts less strain on the wires.

Still, Faibus predicted no short-term respite from the recent stresses on the power system. "There's no question that these kinds of problems will be continuing," he said.