PJM Interconnection expects peak electricity demand this summer to exceed last year’s levels as the weather is expected to be hotter than usual, which could give a boost to local natural gas demand.

Based on a National Weather Service forecast calling for above-normal temperatures in its service territory, PJM expects electricity use to peak at around 151,000 MW this summer. Last year, peak demand across the nation’s largest grid hit 150,830 MW. PJM’s all-time highest power use was 165,563 MW in the summer of 2006.

“Summer is when we see our highest electricity use,” CEO Andrew Ott said. PJM has 183,454 MW of installed generating capacity available. While it’s also required to have a reserve of 16% of the forecasted demand level, the grid operator said it expects to have a reserve margin this summer of more than 28%, or around 40,000 MW.

At the end of last year, about 40% of its installed capacity was natural gas, according to the independent market monitor, which said earlier this year that gas-fired electricity output exceeded coal-fired generation for the first time in its history in 2018.

Gas-fired plants have proliferated in the region due to abundant supplies from the Appalachian Basin and low costs. The facilities have run more often in recent years too. The increase in PJM’s capacity factors, an indication of how often a generator is run, for gas-fired facilities is the largest of any regional transmission organization in the country over the last five years, the Energy Information Administration said late last year.

PJM serves 65 million people in 13 states and the District of Columbia. Its footprint stretches from the Mid-Atlantic states to parts of the South and the Midwest.