For the third time in a month, Commonwealth Edison reached all-time record level demands for electricity in Northern Illinois.

On July 15, customer demand peaked at 16,211,000 kilowatts, a figure that Mario Fontana, Com Ed DeKalb district manager, said was not expected to be reached until 1990.

Com Ed sold 196,000 megawatt hours of electricity July 24, 164,000 of which came from nuclear sources.

Com Ed owns 12 nuclear plants in Illinois. “We have so many nuclear plants because we are looking ahead to the future,” Fontana said.

James Seidita, Citizens Utility Board research director, said Com Ed has built three new nuclear power plants in Illinois. However, he said he did not think they were necessary.

“Only a fraction of their overall potential is being used. They (Com Ed) close a lot of their nuclear plants in the summer for cleaning and maintenance,” Seidita said. “Just because the new plants are operating, they make the claim that all their plants are needed.”

Fontana said it takes 10 to 15 years to build a nuclear plant, and they began construction early so they would not be 10 years behind.

“We knew we’d have overcapacity for awhile, but we wanted to get them done to meet future demand,” Fontana said.

Seidita said these projections were made on the assumption that Illinois would have a normal growth rate and normal weather.

“This issue goes back to 1970,” Seidita said. “Com Ed pulled out a calculator and figured that the growth rate would be seven percent each year. But some years it grew one percent, and other years there was a negative growth rate (for electricity demand). Meanwhile, Com Ed was getting tax breaks for continuing construction of their plants.”

Fontana said as a whole, Com Ed had a growth rate of seven percent in 1988, and the DeKalb district had a 13 percent increase alone.

“The economy is doing well and so are we, and not just because of new customers,” he said. “Through the end of May, the rates for DeKalb are 14 percent below the levels of the comparable period in 1987.”

Seidita said, “You build a plant which will be useful for 30 years, but only use it for seven. It’s not like we’re getting a bargain.”

He said Com Ed claims to have a 15 percent reserve margin in case of high demands, but actually has a 40 percent margin. A reserve margin is the amount of electricity kept on reserve in case of high demand.

“We have more than a 15 percent margin without even using the three new plants,” Seidita said.

“On a peak day in Illinois, using all the electricity needed, Edison has enough extra idle capacity left over to power Los Angeles on their peak day,” Seidita said.