Man checking home fuse box by candlelight during power outage. According to NERC, this summer is likely to bring reliability challenges to the electric grid, which threaten power failures throughout many regions of the U.S. Credit: iStock/aquaArts studio
Last week, the non-profit North American Electric Reliability Corporation (NERC) released its 2023 Summer Reliability Assessment, giving a dire warning that, should summer temperatures spike above normal averages, “the U.S. West, Midwest, Texas and Southeast, New England and Ontario, may experience resource shortfalls.” NERC convenes regional electric grid operators, sets standards and is recognized as one of the foremost authorities on reliability in the electric grid.
While the assessment found that power supplies are probably sufficient for an average or below-average summer, it also noted that weather officials are expecting El Niño conditions and above-normal temperatures for much of the United States, creating exactly the kind of high-demand situation experts are concerned about.
This assessment echoed previous assessments from NERC warning that renewables are not yet ready to fully replace fossil fuels, even as coal and gas plants continue to retire at unprecedented rates as a result of policy choices. Natural gas supply and infrastructure continues to be “vitally important to electric grid reliability, even as renewable generation satisfied more of our energy needs,” according to the report.
The report singled out several regions like the Western Interconnection and Midcontinent Independent System Operator (MISO) that are already highly dependent on intermittent renewable power sources like wind and solar whose generation is weather dependent. That makes it especially critical to have sufficient supplies of dispatchable resources like coal, gas or nuclear on hand at all times to make up the difference if weather conditions change.
In the Western Interconnection region, demand for power tends to rise just as the sun and solar energy generation decline, challenging the grid’s ability to meet demand. This situation played out last September in California, when a heat wave hit most of the state and resulted in 10 days of Flex Alerts, warning of rolling blackouts if customers did not immediately curb usage. California was able to maintain power thanks largely to natural gas, with it making up 60 percent of the power mix during the hot summer week.
MISO and SERC-Central also face challenges should demand rise this summer. SERC-Central, which includes parts of Tennessee, Kentucky, Arkansas and Missouri, will have a demand increase of over 950 megawatts when compared to last year. However, growth in power resources has been flat, creating a serious challenge.
In New England, anticipated resources are expected to be lower than in 2022 because of retirements, with NERC predicting that the region will depend on neighboring areas to supply power in many conditions—risking blackouts if they do not have spare capacity available. However, the region is already no stranger to shortages of energy, having struggled with a severe natural gas shortage this past winter due to a scarcity of natural gas pipelines and infrastructure.
The assessment also described additional reliability risks for U.S. power systems, noting that wind and solar resources continue to face “tripping” issues, underscoring the need for dispatchable resource supplies to kick in when these resources go down.
Low inventories of replacement distribution transformers, labor shortages and trouble securing equipment are other reliability risks for the grid, according to the report. “Difficulties in obtaining sufficient labor, material and equipment as a result of broad economic factors has affected preseason maintenance of transmission and generation facilities in North America.” In the case of severe storms or hurricanes, a low supply of replacement distribution transformers could also slow restoration efforts. “A survey of the American Public Power Association revealed that many utilities have low levels of emergency stocks that are used for responding to natural disasters and catastrophic events.”
Supply chain challenges have also led to delays or cancellations of maintenance activities to ensure facilities are ready for summer conditions, further threatening reliability. Interconnections of new generation in the U.S. Southeast and Western Interconnection are facing delays, further impeding the region’s ability to meet peak summer demand.
Power losses and shortages due to insufficient supply have become commonplace during winter and summer months in the United States, as retirements continue to accelerate while renewables face their own supply chain issues that have delayed many projects. Since renewables like wind and solar are intermittent, they are also far from a one-for-one replacement for a given MW of coal or gas.
EPA’s recent “Good Neighbor” power plant ruling may create even more headaches for grid operators. “Coal and natural-gas-fired generators in states affected by the Good Neighbor Plan will likely meet tighter emissions restrictions primarily by limiting hours of operation in this first year of implementation rather than through adding emissions control equipment.” This new policy, though intended to reduce emissions, may further threaten reliability, NERC warns.
NERC’s reliability assessments continue to sound the alarm, yet policy is largely moving in the other direction—hastening retirements without ready replacements.
These issues will only get worse as the economy moves toward electrification. Cars, kitchen appliances, indoor heating and trucking will eventually depend on our power grid. America must prioritize an energy expansion, not just a transition, if we are to meet this demand. The grid will need more of everything- more renewables, yes, but also more dispatchable resources like gas to back it up. The power grid will need more power from more sources to meet demand and preserve reliability. If planning does not adequately prioritize reliability, we risk a full shut down of the economy on a hot summer day.
A strong energy mix of intermittent sources and dispatchable resources is crucial to our power grid and meeting climate goals. The power grids in each region of the country must reflect that balance. As the report noted, several systems will be relying on neighboring regions for energy imports during demand spikes, but as retirements spread, it becomes increasingly likely that there will not be enough spare capacity anywhere.
Addressing that threat should be top of mind for policymakers and regulators this summer.