2022 Maine power outages quantified

Maine electricity customers experienced more frequent and longer power outages on average in 2022, compared to the national average, according to recently released federal data.

According to the U.S. Energy Information Administration, U.S. electricity consumers in 2022 experienced one or two outages, averaging about 5.5 total hours of power outage. According to EIA, major incidents like storms are most likely to cause outages with extended durations, while heavily forested states are most likely to experience a higher frequency of outages.

EIA tracks reliability and outages through two key metrics: SAIFI (which measures the frequency of service interruptions) and SAIDI (which measures duration). Some states are outliers with respect to both these metrics of electric grid reliability. The chart below, prepared by EIA, shows how various states' utilities performed in 2022 with respect to SAIDI and SAIFI. 

The average customer in Maine experienced three outages totaling over 15 hours without power in 2022. Only Alaska and Tennessee experienced more frequent outages than Maine, and only Florida and West Virginia experienced greater total durations of outages than Maine. Maine's outage duration in 2022 was roughly the same as in 2021; both were down compared to 2017, when the average Maine customer went without power for about 42 hours. According to EIA, "Power interruptions resulting from falling tree branches are common, especially because of winter ice and snowstorms that weigh down tree limbs and power lines."

Meanwhile, the District of Columbia had both the lowest frequency of service interruption and the lowest total outage duration, with an average of just 34 minutes without power in 2022. Delaware, Rhode Island, Nebraska, and Iowa also had top rankings for low outage duration.

ISO-NE 2022 generation portfolio emissions report

New England's electric power generation fleet emitting slightly less carbon dioxide in 2022 relative to 2021, according to the grid operator's 2022 ISO New England Electric Generator Air Emissions Report.

ISO New England operates the regional transmission grid and the wholesale market for electricity. In support of this role, ISO-NE tracks the portfolio of generation resources used in the region, as well as the resources' emission characteristics.

According to ISO-NE, New England generation emitted 33,382 kilotons of carbon dioxide in 2022, a decline of two-tenths of a percent relative to 2021. The grid operator reports an average 2022 emission rate of 643 pounds of CO2 per megawatt-hour of New England generation. 

Over longer time scales, air emissions from New England's power plants have decreased significantly. "From 2001 through 2022, CO2 emissions fell by 37%, NOx emissions fell by 79%, and SO2 emissions fell by 98%."

While carbon dioxide emissions decreased slightly again this year, sulfur dioxide (SO2) emissions increased to 3.38 kilotons, climbing over 60 percent relative to 2021. The grid operator attributes the sulfur emissions to increased reliance on fuel oil for electric generation:

More electricity came from oil-fired generators in 2022 than in the previous four years combined. At 1,845 GWh, production from these resources in 2022 was eight times higher than in 2021. Oil has a high sulfur content, so SO2 emissions rise when these resources produce more power.

The chart below shows the region's generation portfolio on a monthly basis for 2022; the red and black bars at the top of each month's column represent oil and coal use. The largest blue bars represent natural gas, while the largest orange bars represent nuclear power.

ISO-NE attributes increased use of oil for power generation to "record high natural gas prices associated with the Russia-Ukraine conflict, and thus an increase in regional reliance on oil versus natural gas." The grid operator also says that decreases in coal generation largely offset the increased oil use for purposes of CO2 and NOX emissions.