Power Supply Is Expected to Be Tighter

U.S. electricity supplies this summer will be tighter than last summer as demand for power has grown more quickly than new generation, and parts of California and Connecticut will be at risk of blackouts under extreme conditions, an industry group said Monday.

Generating capacity in the U.S. and Canada will be 17% higher than overall peak demand, down from 17.5% during last year’s peak, according to the North American Electric Reliability Council.

Power supplies will have increased by 1.4% over last summer, with 11,800 megawatts of new capacity, mostly from natural-gas-fueled plants and wind turbines. Demand has grown an average of 1.4% annually in the last 10 years.

NERC said generating resources and transmission will be adequate this summer to serve power needs under normal weather conditions across the U.S., Canada and parts of Mexico. But it added that “extreme weather continues to present a significant reliability risk.”

“Although generating capacity resources will increase over last summer, peak demands are also increasing, and we are seeing a decline in capacity margins in most regions,” Rick Sergel, NERC chief executive, said in the statement.

Sections of Southern California and part of Connecticut may not have enough transmission capacity to prevent blackouts during the hottest weather, the group said. Power-plant failures combined with hotter-than-normal weather in those areas could force grid operators to cut off some customers.

Southern California relies on importing power from neighboring regions to meet demand, and transmission lines will operate close to capacity for much of the summer. Edison International’s Southern California Edison utility may need to cut supplies to some customers if transmission falters, the report said..