New England’s electric grid operator issued a rare energy emergency last week when power generation unexpectedly dropped off during a heat wave.
ISO New England said it had to call in reserve power resources for a few hours on August 1 to meet surging electricity demand as the region sweltered in temperatures over 90 degrees.
The grid operator said that increased energy use in the early evening surpassed morning forecasts. And there were unplanned power plant outages including the loss of a 350 megawatt resource.
That created a capacity deficiency that prompted a power caution alert signaling the grid was under stress and tapping reserve power, said ISO New England spokesperson Matt Kakley.
"It doesn't mean that we are turning people's power off or calling for any sort of controlled outages, but things are a little tighter on the system than we normally would like," Kakley said.
"This is just really, you know, us using some of our tools that we have available to balance that supply and demand for a short period on a given day when something unexpected happens," Kakley added.
The power shortage started at 4:45 p.m. and ended five hours later as energy demand eased, according to ISO New England.
Power generators that failed to meet their supply obligations during the event will be fined by the grid operator under its pay-for-performance rule. Generators that produced more than they had to, however, will be rewarded, according to ISO New England.
The August 1 event was the second time this summer the grid operator declared a power caution during a heat wave. A similar shortage that prompted a need for reserve resources occurred on June 18.
Power supply shortages, called capacity deficiencies, have happened in New England only five times since 2016.
