Smoke from wildfires in Canada traveled to New England, significantly lowering production from solar resources in the region compared to what ISO New England would expect absent the smoke, the grid operator said on June 8.
Meanwhile, the New York ISO also said that smoke cover caused by the wildfires curtailed solar energy production, while the PJM Interconnection said that smoky conditions throughout the regional transmission organization caused a reduction in visibility, reducing solar, and keeping temperatures several degrees lower than usual.
Most solar resources in New England are connected to the distribution system and reduce demand on the regional grid when they are producing electricity. Decreased production from these resources has the effect of increasing demand on the regional grid, ISO-NE said.
“ISO New England forecasters have worked to adjust consumer demand forecasts to account for these differences, as modeling software, which relies on weather forecasts, is anticipating greater production than what ISO operators are observing in real time,” it noted.
The smoke also lowered actual temperatures in New England compared to what weather models were forecasting. This leads to lower demand on the regional grid, as there is less need for things like air conditioning, it said.
These two factors -- decreased production from solar resources and decreased consumer demand due to lower temperatures -- has made forecasting demand for grid electricity challenging.
“It’s difficult to determine the exact impact of each of these factors, given that there are many variables affecting consumer demand for electricity at any given moment,” it said.
In forecasting real-time and future demand for electricity, ISO New England relies on historical data from similar days, adjusting for changing system conditions. “Because these smoky conditions are unprecedented in the region, there is little, if any, historical information to rely on, creating further complications in generating accurate forecasts.”
Despite these complications in forecasting, ISO New England said it continued to manage the regional grid under normal operating conditions, and did not anticipate this changing. The ISO has long-established procedures in place to maintain system reliability, should they be needed, it said.
As for NYISO, based on data compiled by NYISO forecasters, wildfire smoke cover significantly reduced incoming solar irradiance across the state on June 6 and 7, NYISO spokesperson Andrew Gregory said.
As a result, total peak solar energy production (behind the meter and front of meter) over the two days was 1,466 fewer megawatts than forecasted.
“While the haze caused by the ongoing Canadian wildfires had a significant impact on solar energy production, the two-day total peak production still reached 4,405 MW. The NYISO will continue to monitor this situation as it develops,” said Gregory.
With respect to the PJM Interconnection, the grid operator for the Mid-Atlantic region said that smoky conditions throughout the RTO caused a reduction in visibility, reducing solar, and keeping temperatures several degrees lower than usual.
PJM spokesperson Dan Lockwood on June 9 said it is difficult to single out the effect of smoke alone, “especially when PJM has not seen an expansive plume like this.”
However, the cooler temperatures and decreased visibility “are similar to what we experienced during the period of July 19-21, 2021, when the RTO was covered with smoke from wildfires in the western U.S.”
PJM “is closely watching the smoke maps and taking these factors into consideration as it forecasts load for its zones,” he said.
