PJM grid facts
Millions of people served: 61
Miles of transmission lines: 62,556
2012 generation capacity: 183,604 megawatts
Square miles of territory: 243,417
Extreme heat Tuesday prompted the electricity grid operator for Ohio and 12 other states to tell utilities to temporarily cut power to customers to prevent an uncontrolled blackout.
PJM Interconnection said Wednesday that a new record for September peak power use occurred Tuesday with demand for 144,370 megawatts of power. By comparison, PJM said, the 2012 September peak demand was 130,000 megawatts. A megawatt equals 1 million watts.
Tuesday’s extreme heat combined with local equipment problems created emergency conditions in Indiana, Michigan, Ohio and Pennsylvania, PJM said, forcing it “to direct local utilities in those areas to immediately and temporarily cut electricity to some customers to avoid the possibility of an uncontrolled blackout over a larger area that would have affected many more people.”
No cutbacks were called for in the Dayton area. Most of the Ohio issues were in the northern portion of the state in an area covered by utility First Energy, parent company of Ohio Edison, which covers Springfield, said Ray Dotter, spokesman for PJM. But Springfield was spared.
“Extreme heat in the western region of PJM resulted in record demand for September at a time when many power plants and some transmission lines were off for seasonal maintenance,” said Terry Boston, PJM’s CEO. “Our only option to prevent a potential equipment overload and failures that would cause a much bigger interruption was to call for emergency relief in the form of controlled outages. We sincerely regret that conditions on the grid yesterday required us to call for emergency reductions in consumer demand.”
PJM serves 61 million people in all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and the District of Columbia.
This week’s hot weather forced several area schools to let students out early, with one closing. Temperatures inside a classroom at the St. Luke School in Beavercreek reached 93 degrees on Tuesday, said principal Leslie Von Drell. She decided to close the school on Wednesday after seeing the forecast.
“Parents were very appreciative,” Von Drell said. At least four other Miami Valley school districts dismissed students early on Wednesday as a precautionary measure.
“There’s definitely not going to be any learning done in this heat,” said Fairborn City Schools Superintendent Dave Scarberry. He made the call on Sunday to let students at Fairborn’s non-air conditioned buildings leave two hours early on Tuesday and Wednesday.
Scarberry said even with three fans operating, temperatures in one classroom reached 90 degrees on Tuesday.
WHIO-TV Chief Meteorologist Jamie Simpson declared it a heat wave with three days in a row of temperatures 90 degrees or higher. Monday it hit 93, Tuesday 96, and as of 3 p.m. Wednesday, 90. A cold front should break the heat wave today.
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