Halfway through a US summer of punishing heat domes and record-high temperatures, air conditioners are churning and energy bills are soaring.

But a closer look at how such costs play out reveals vast disparities among states and demographic groups — suggesting a complex American energy reality that goes beyond partisan talking points and shows the challenges utilities face in a warming world, industry experts said.

Between 2018 and 2023, average US household electricity prices rose 21.9%, data from S&P Global Commodity Insights showed. Within that average were increases as high as 65.6% in Maine and 51.3% in New Hampshire, while New Mexico and North Dakota saw only a 6.6% rise. Wyoming and Kansas residential power prices were slightly lower in 2023 than in 2018, while Florida's jumped 36%.

Economywide cumulative inflation was 22.2% during the same six-year period, according to the Federal Reserve Bank of Minneapolis.

US power retail costs are inconsistent because bills now include charges that may have nothing to do with the costs that utilities incur when generating and distributing electricity, said Severin Borenstein, director of the University of California, Berkeley's Energy Institute at Haas and board member of the California ISO.

"I think the common theme here is we pay for a lot of stuff through price per kilowatt hour that is not a cost per kilowatt hour," Borenstein said in an interview. "Wholesale power prices have been very moderate over the last year, but we're still seeing retail prices grow."

In California, for example, costs associated with wildfire mitigation and liabilities accounted for nearly 13% of the average monthly bill that Pacific Gas and Electric Co.'s residential customers paid in 2023, according to the state's Public Utilities Commission. Wildfires that have devastated parts of California in recent years have been attributed to climate change.

Maine had the highest power cost increase of any state between 2018 and 2023, per Commodity Insights data. The hike was driven mainly by deferred costs of imported natural gas but also reflects deferred storm costs and stranded assets from a net metering program, a spokesperson for the Maine Public Utilities Commission said in an email.

Behind the rhetoric

Rising energy prices have become a political football during this election year, as critics of the Biden administration's climate policies and state clean energy mandates have argued that American families are caught in the middle.

"Doubling down on policies to restrict oil and gas, to retire baseload power generation and to promote widespread unaffordable, unreliable electrification is not how we secure our energy future," Rep. Cathy McMorris Rodgers (R-Wash.), chair of the US House Energy and Commerce Committee, said during a May 1 congressional hearing. "Unfortunately, it's Americans that are feeling the impacts of this rush-to-green agenda."

Brendan Pierpont, director of electricity modeling at the think tank Energy Innovation, decided to dig into the data to try to understand why utilities in recent years began to ask regulators for large rate increases. Those requests coincided with the narrative arguing that clean energy investments drove such cost increases, he said.

"What we found was, first, that there's not really a systematic relationship between states that have increased renewable energy shares and those that saw large rate increases," Pierpont said in an interview. "And then when you zoom into some of the states that had rate increases that exceeded inflation, like California, you see costs associated with mitigating wildfire risk just ballooning."

Such costs continue to climb. California regulators in 2023 approved a $2.6 billion multiyear rate increase for Pacific Gas and Electric Co. that went into effect in January. More than 85% of the revenue will be used to reduce risks in the utility's electric and natural gas operations, primarily from wildfires.

New England and some Appalachian and Midwestern states also experienced rapid increases in electricity costs in recent years, and all for unique reasons, Pierpont concluded in a study published July 9.

Volatile wholesale gas prices caused power bills to spike in recent years in Massachusetts and several other New England states that are heavily dependent on imported natural gas, Pierpont said. The Energy Innovation analysis covered increases going back to 2010.

Appalachian states such as West Virginia have sought to delay the retirement of coal plants, necessitating expensive environmental upgrades whose costs are passed on to consumers. West Virginia household power rates rose 26% between 2018 and 2023, the Commodity Insights data showed.

Households feel the squeeze

At the receiving end of rising power rates are millions of residential customers.

Nearly 24% of US households said they were unable to pay at least one monthly energy bill in the past year, according to a July 16 report from the National Energy Assistance Directors Association and the Center for Energy Poverty and Climate. That number rose to 32% for households of color and to 37% for low- and moderate-income households, according to the study based on US Census data.

"We don't have an entitlement program for energy bills like we have for foods or Medicaid," Mark Wolfe, executive director of the National Energy Assistance Directors Association, said in an interview. "With energy assistance as a discretionary grant program, when the money runs out, it's over."

The federal Low Income Home Energy Assistance Program, which helps struggling households with their energy bills, received about $4 billion from Congress for fiscal year 2024, down from over $6 billion in fiscal year 2023. Wolfe said the reduced funding adds more pressure on the states. Until a few years ago, he noted, 80% of the funding went to home heating in the winter and 20% to cooling, but with summer heat waves lasting longer, the ratios are changing.

Whose affordability problem?

Some utilities in high-cost states have responded by rolling out programs to try to mitigate rising energy costs and address the needs of households whose cooling needs are growing in tandem with global temperatures. Without help, people can die, Wolfe said.

In 2023, Eversource Energy said it would offer up to a 50% discount on bills for New England customers facing financial hardship. The states the utility serves — Massachusetts, Connecticut and New Hampshire — were among the top five for residential power rate increases between 2018 and 2023.

"The affordability problem falls heaviest on utilities," Wolfe said. "They have to collect when people run behind on their bills and have to run shut-off programs and you talk to any utility, they don't like shutting people off from power. But utilities are not social service organizations. They're set up to make sure the power plant runs and the wires are up."

In states with high power rates, such as California, energy assistance programs provide some help without solving the underlying problem, Borenstein said.

"Which is why I'm a bigger fan of taking a lot of these costs off the bills and instead put them on the state budget," the business professor said. "We're paying for seawalls, flood protection, wildfire protection, because politicians like to have somebody else pay for things."