In a significant move towards addressing climate change, the Biden administration has introduced a new rule aimed at curbing emissions from power plants. The rule requires both coal plants and new gas plants to install carbon capture technology to mitigate 90 percent of their emissions or find alternative ways to achieve equivalent climate protections. While this crackdown on planet-warming emissions is expected to accelerate the transition away from coal and towards renewable energy sources, experts predict that it may lead to the retirement of more coal plants and encourage power companies to invest in renewables.

Christopher Knittel, a professor of applied economics at MIT, highlighted that the decline in coal generation is already underway due to factors such as fracking, which has significantly lowered natural gas prices. However, with the new rule, Knittel expects the transition to be expedited. The Environmental Protection Agency's (EPA) analysis indicates that the rule could result in a nearly 25 percent increase in the amount of coal power plants retiring between 2028 and 2035. Without the rule, 84 gigawatts of coal power would have retired during that period, but the number is now estimated to jump to 104 gigawatts due to the rule.

Julia Attwood, an industrial decarbonization specialist, estimated that around 44 gigawatts of coal power was already slated to retire by the end of 2030, but the new rule would lead to an additional 30 to 40 gigawatts going offline in that timeframe. This would result in the closure of around 46 to 62 coal plants, considering the average coal plant generates about 0.65 gigawatts. Attwood explained that many coal plants will simply be pushed towards retirement due to the cost of implementing carbon capture technology.

Not surprisingly, the new rule has faced opposition from coal advocates, industry representatives, and Republicans. Cecil Roberts, president of the United Mine Workers of America union, expressed concerns about the impact on coal mining jobs and called the rule a "funeral date" for thermal coal mining in America. Roberts also criticized the administration's failure to create job opportunities in the energy transition for displaced coal miners.

Senator Shelley Moore Capito, a Republican from West Virginia, announced her intention to introduce legislation aimed at overturning the rule. Capito argued that the rule threatens affordable and reliable energy access for households and businesses across the country.

Aside from driving the country further away from coal, the rule is expected to accelerate the ongoing shift towards renewable energy. The EPA projects that by 2030, the rule will increase the share of power supplied by renewable energy sources by an additional 4 percent. However, this impact is expected to diminish over time, with just a 1 percent increase projected for 2040.

Experts believe that the rule will create opportunities for renewables, as it will free up capacity on the grid that can be filled by renewable energy sources. While renewables have intermittency challenges due to weather conditions, the exclusion of existing gas plants from the rule's requirements may keep some of them online, mitigating concerns about renewable energy's reliability.

Mark Thurber, associate director at Stanford University's Program on Energy and Sustainable Development, emphasized the intermittency of renewables and their inability to fully replace coal. However, Attwood pointed out that the rule's exclusion of existing gas plants may delay the closure of those plants, as it would be cheaper to maintain them rather than build new gas plants with carbon capture technology.

The Biden administration initially proposed restrictions on emissions from existing gas plants under this rule but dropped those provisions, signaling a possible intention to address them in a separate rule. However, the timeline for such a rule is uncertain, as it may depend on the outcome of the upcoming presidential election. If President Biden is not reelected, a return of former President Trump could result in less stringent climate regulations on power plants.

The implications of the new rule on power plant emissions remain a topic of discussion, particularly regarding existing gas plants. While it is uncertain how these plants will be regulated in the future, experts agree that the rule will facilitate the transition from coal to renewables and contribute to the reduction of greenhouse gas emissions from the power sector.