A rapid build-out of energy-hungry data centers to support artificial-intelligence and cloud services is reshaping U.S. electricity markets. Forecasts from Apollo Global Management and the International Energy Agency show data-center power use is on track to double in the next five years, having already reached about 4.4% of national consumption in 2023. The U.S. Department of Energy estimates the share could climb to as much as 12% by 2028. The surge is rippling through utility costs. Market watchdog Monitoring Analytics attributes 70%, or $9.3 billion, of last year’s increase in electricity charges on the PJM Interconnection grid to higher data-center demand. Wood Mackenzie found that most of the 20 preferential data-center tariffs in 16 states do not cover the cost of the new gas-fired plants and transmission upgrades needed, effectively shifting expenses onto households and smaller businesses. State governments are moving to contain the fallout. Oregon in June ordered regulators to craft a dedicated—presumably higher—rate class for data centers, while New Jersey has commissioned a study into whether consumers face “unreasonable” hikes from interconnection costs. Five governors, led by Pennsylvania’s Josh Shapiro, have asked PJM to revise its pricing rules, and some regulators are floating requirements for data-center operators to secure their own generation. Pressure is building from consumers. Florida Power & Light has requested an increase that would add roughly $21 a month to residential bills, and New Jersey customers have reported their summer invoices tripling since last year. Consumer advocates also warn that recent federal policy changes reducing clean-energy subsidies could add more than $100 a year to typical household bills over the coming decade. The Data Center Coalition and leading operators such as Microsoft, Google, Amazon and Meta say they are prepared to shoulder their fair share of infrastructure costs. Regulators contend that without clearer cost allocation—and solutions for the water and gas needed to keep servers running—the pace of AI-driven expansion could strain grids and wallets alike.