The shift occurred as the cost of wind power and other renewable energy is rapidly declining and coal is being pushed out by natural gas.
Wind turbines generated more electricity than coal-burning power plants across the United States in March and April, outstripping the dirtiest fuel for two consecutive months for the first time, according to the Energy Information Administration.
The crossover in wind and coal generation is the latest milestone in the country’s energy transition as renewables rise and coal declines. In recent years, breakthroughs in technology have lowered the cost of building new wind turbines, solar panels and battery storage, helping renewable energy replace coal as the cheapest power source in many places.
Renewable energy has also gotten a boost from tax credits awarded under the Inflation Reduction Act, the climate law Congress passed in 2022. And states have passed regulations mandating that utilities transition away from fossil fuels, particularly coal. More than 20 states — including Minnesota, North Carolina and Nebraska — have enacted legislation that requires utilities to get all their electricity from clean, carbon-free sources by 2050 or before.
Those three factors — shifts in the economics of energy, federal tax credits and state mandates — have led to explosive growth in renewable energy in recent years, said Timothy Fox, a managing director at ClearView Energy Partners, a consulting firm.
“When project developers are considering which resources to deploy in the grid, they look 20, 30, 40 years down the line,” Mr. Fox said. “From that perspective, it’s hard to envision building a coal plant today.”
Environmentalists have also focused on the economics of coal-fired power plants in recent years, a strategy that contributed to the closing of all coal plants in New England. In Michigan and Louisiana, climate groups successfully persuaded state regulators to stop utilities from recouping their losses from burning coal by passing the costs to customers.