Summer is, of course, already the most expensive time of the year for power bills in most of the country, particularly as climate change sends temperatures higher. And the amount of the increase will vary from region to region, but some consumers could be facing bills that are as much as 45% higher.

Pennsylvania regulators issued a warning earlier this month that customers will see increases of 6% to 45% effective June 1. Eversource, which serves New Hampshire, Massachusetts, and Connecticut, said at the start of the year that customers could see between a 23% and 25% increase through at least June 30. And South Carolinians are facing jumps of 5% to 19%.

Inflation is playing a role in the energy price hikes, but the real culprits are natural gas prices and geopolitical events.

Natural gas is used to power turbines at just under half of America’s energy companies, which generate the electricity that’s delivered to homes. Russia’s invasion of Ukraine has driven up the cost of that resource, which energy companies are passing along to consumers.

Also, as European nations reduce their dependence on Russian exports, including natural gas, they’re relying on the U.S. for assistance, which reduces domestic supplies.

Overall, according to the U.S. Energy Information Administration, the average American home saw its electric bill jump 4% in February compared to a year ago. (Those are the most recent figures.) Florida, Hawaii, Illinois, and New York saw the biggest increases, going up about 15%.

Don’t expect the price of electricity to drop anytime soon, either. Power companies are preparing to upgrade and repair their grids to better protect against natural disasters like last year’s winter storm in Texas. Those costs will be passed along to the consumer as well.