New England's power grid operator expects the region to have sufficient supplies to meet peak consumer demand for electricity during the upcoming summer under both typical and extreme weather conditions. And the region's bulk power system is ready to meet that demand despite the upcoming May 31 retirement of one of New England's three nuclear power plants, according to the ISO New England.
The ISO-NE in a May 15 press release announced that its 2019 summer peak demand is forecast to be 25,323 MW under typical weather conditions. If the six-state region in the northeast U.S. experiences extreme weather conditions, including an extended heatwave, ISO-NE said demand could increase to 27,212 MW. The ISO-NE said the region has more than 32,000 MW of capacity expected to be available to meet that demand, which is driven largely by the use of air conditioning.
The seasonal forecast takes into account contributions from all generation resources, including those with and without a capacity supply obligation, unplanned generator outages, electricity imports from neighboring regions, and new and retiring generation resources. This year's summer forecast factored in about 2,900 MW of demand-reducing energy efficiency measures, which have increased incrementally by 200 MW since 2018.
The ISO-NE also expects behind-the-meter solar photovoltaic installations to reduce demand by more than 700 MW during the peak hour. This is an additional 100 MW reduction compared to 2018. While New England has more than 3,000 MW of solar PV installed, the grid operator explained that those systems produce their highest output in the early afternoon hours.
The growing widespread use of solar power in New England has effectively pushed the region's peak hour of demand later in the day, when the sun is lower in the sky and less solar generation is produced, the ISO-NE said. Rather than peaking during the mid-afternoon, as was the summer norm once, demand for grid power now peaks in the early evening hours, the grid operator added.
In the summer of 2018, New England demand for electricity peaked on Aug. 29 at 25,899 MW, which was the region's highest peak in five years. ISO-NE's all-time record peak demand was set on Aug. 2, 2006, when demand reached 28,130 MW as a result of a prolonged heat wave.
Notably, summer 2019 effectively kicks off with the planned May 31 retirement of Entergy Corp.'s 680-MW Pilgrim facility in Plymouth, Mass. As Pilgrim shuts down, the ISO-NE said, 1,185 MW of capacity from new resources is coming online. Those new resources include three dual-fuel plants that can burn either natural gas or oil to generate electricity. In addition, five new grid-scale solar facilities are expected to add a nameplate capacity of about 87 MW, while a new wind farm will add about 44 MW of nameplate capacity, the ISO-NE noted.
However, ISO-NE President and CEO Gordon van Welie recently acknowledged that New England's fuel security problem will only worsen with the loss of Pilgrim, as the region continues to move away from conventional generation toward a generation mix of intermittent renewable and interruptible gas-supplied resources.
Entergy announced Pilgrim's retirement in October 2015 and, at the time, cited low wholesale electricity prices — fueled by an influx of cheap natural gas — as the "key driver" behind the decision.
The Northeast Power Coordinating Council, or NPCC, recently released its annual reliability assessment for an area that includes the ISO-NE region, New York, Ontario, Quebec and Canada's Maritime provinces. The regional reliability organization said that its larger, combined Northeast U.S.-Eastern Canada region is forecast to have peak summer demand of 103,548 MW, or about 600 MW lower than the 2018 summer forecast.