Solar, efficiency drive declining peak load in ISO New England
- The grid operator for most of New England reports it expects to see declining energy use and peak load over the next decade, largely due to efficiency and behind-the-meter solar.
- Before factoring in efficiency and distributed resources, ISO New England predicted overall electricity use would grow 0.9% annually over the next 10 years. However, once those load modifying resources are considered, the operator concluded both overall energy use and peak demand will decline.
- Efficiency is expected to save the region 2,059 GWh annually, on average. Solar PV is expected to produce 2,162 GWh of total annual energy savings in 2018, rising to almost 4,800 GWh in 2027.
Gas and nuclear make up the bulk of New England's generation, but efficiency measures and solar being installed behind the meter are reversing what otherwise would be steady demand growth. A similar trend is occurring in New York.
The grid operator has published its 2018-2027 Forecast Report of Capacity, Energy, Loads, and Transmission, which supplies the assumptions used for system planning.
The system's gross forecast, not including solar and efficiency, shows expected demand growth of 0.9% annually over a 10-year period, from 142,488 GWh this year to 154,364 GWh in 2027. However, once behind-the-meter efforts are factored in, overall use is projected to decline by 0.9% annually, from 124,252 GWh this year to 114,980 GWh in 2027.
Peak demand under normal summer weather conditions would grow 0.8% annually, but efficiency and solar will turn that into a decrease of 0.4% annually.
New England's assessment mirrors the dynamics in the New York ISO, where the operator recently issued a report predicting a declining load for the next decade — mostly due to distributed solar, and to a lesser extent, energy efficiency.
New England has been rapidly growing its rooftop solar, and those new resources are showing up in changing load shapes. One day last month, consumers in the region had a higher nighttime peak than during the day.
Officials said the milestone had been expected, due to the proliferation of distributed resources. On April 21, the New England ISO estimates distributed solar was producing about 2,309 MW at 1:30 p.m —an extremely high percentage of the grid's 2.4 GW of nameplate capacity.
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