A winter storm continues to blow through the Washington, D.C. region tonight. Snowflakes dance through the air, temperatures plummet toward an expected low of eight degrees Fahrenheit tomorrow morning, and people expect that PEPCO and other regional utilities will keep providing electricity.
As of late afternoon, PEPCO, the utility that sells and delivers power to homes and businesses within D.C. and parts of nearby Montgomery and Prince George’s Counties, reported only 58 outages in its service territory, 22 of them in D.C. That number was down by early evening.
“We’re not out of the woods yet, but things are fairly normal right now,” said Robert Hainey, a PEPCO spokesperson.
“So far, we have not had to call any emergency procedures,” said Paula DuPont-Kidd, a PJM spokesperson.
The complexity of keeping electricity flowing to homes and businesses is as delicate a process as driving on the icy roads on this snowy evening.
Utilities and regional transmission organizations must match electric supply and customer demand, instantaneously, in real time. That means PJM and PEPCO must coordinate electric power supply with the thousands of changing demands for electricity throughout the day.
Utilities serve these many local demands with a variety of supply sources. Most of the electricity for PEPCO’s D.C. customers must travel long distances, most are generated by coal or natural gas.
But extremely cold weather can disrupt power supplies. Natural gas compressor stations, which help natural gas flow long distances through interstate pipelines, can stop working properly. Coal piles at generation plants can freeze. Wind turbines can cease to function.
These kinds of supply disruptions can cause electric prices to rise and stress the system. That’s exactly what happened two weeks ago, in early January, when frigid temperatures swept across the country.
The PJM area was particularly hard hit, according to a January 16, 2014 presentation by the staff of the Federal Energy Regulatory Commission, the agency that regulates wholesales and interstate transmission of electricity.
On January 6, PJM electric prices “rose to as high as $1,200 MWh during the evening peak….,” the agency's staff told the Commission.
On January 7, “natural gas prices [in the PJM area] averaged over $70/MMBtu along the I-95 corridor, between Richmond and New Jersey, with some intraday trades close to $100/MMBtu,” according to the staff presentation.
Today’s storm has caused “peak [electric power] loads to go up, but they are no-where near the record-breaking peaks of a couple weeks ago,” DuPont-Kidd said. “We’re not experiencing the same issues or risks we had a couple of weeks ago.”