A bill that would make it harder for Kentucky’s utility regulator to allow utilities to retire coal plants on the state’s electricity grid became law Friday without Gov. Andy Beshear’s signature.?

Senate Bill 4, primarily sponsored by Sen. Robby Mills, R-Henderson, would create a series of prerequisites on the Kentucky Public Service Commission before it could approve a regulated utility’s request to retire a fossil fuel-fired power plant.?

The Democratic governor did not veto the legislation during the ten day period he had to consider the bill after it passed the Kentucky legislature, instead allowing it to become law without his signature. The Republican-backed bill has an emergency declaration, meaning it goes into effect immediately.?

Republican supermajorities in the legislature pointed to concerns over the reliability of the electric grid as reasoning for SB 4 following rolling blackouts that some utilities implemented amid arctic temperatures last winter. Mills and other Republicans referenced past and planned retirements of coal-fired power plants that they say could hinder electricity reliability in the future.?

During a legislative hearing earlier this year about the rolling blackouts, utility leaders instead pointed to key components of a natural gas pipeline that froze as a cause behind the rolling blackouts.?

According to a recent report from the think tank Institute for Energy Economics and Financial Analysis, it was gas and coal power plants that largely failed to perform as expected during the arctic blast. PJM Interconnection, the regional electric grid operator that includes Kentucky, saw coal and gas power plants account for 87% of the PJM’s forced outages on Dec. 24 when energy demand was peaking.

The bill was opposed by almost all Democratic lawmakers, a handful of Republican lawmakers and Kentucky’s investor-owned utilities and manufacturers, saying that such legislation could increase electricity rates for consumers and businesses and could hinder utilities from being able to retire uneconomical, aging coal-fired power plants at the appropriate time.?

Only Democratic lawmakers mentioned the implications on climate change the bill could have as it moved through the legislature. Researchers with the United Nations issued a stark warning last week in its latest report on climate change, urging countries across the globe to slash two-thirds of its carbon dioxide emissions by 2035 to limit the catastrophic effects of rising global temperatures. United Nations Secretary-General Antonio Guterres said last week that humanity was on “thin ice” and that the world needed climate action “on all fronts.”

According to the Associated Press, Guterres specifically called on rich countries to stop using coal by 2030 and have zero-emission electricity generation in the developed world by 2035, including no gas-fired power plants.?

In Kentucky, Louisville Gas and Electric and Kentucky Utilities and the Tennessee Valley Authority are both retiring coal-fired power plants and replacing such electricity generation in part with gas-fired power plants.?

According to the International Energy Agency, coal is the largest global source of electricity generation and largest global source of carbon dioxide emissions that contribute to climate change.