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Environmental policy

Environmental policy

Affordable Clean Energy rule ‘worse than doing nothing’

29 Jul 2019
Capitol Building, Washington DC
(Image courtesy: Shutterstock/orhan-cam)

You’d think that making coal-fired power stations more efficient would benefit the planet. But the policy currently proposed by the US Environmental Protection Agency will likely drive up greenhouse gas emissions, according to a study in Environmental Research Letters (ERL).

In June 2017 president Donald Trump announced that the US would cease all participation in the 2015 Paris Agreement on climate change mitigation. But this move didn’t completely negate the US obligation to regulate greenhouse gas emissions. Back in 2007 the US Supreme Court ruled that the Environmental Protection Agency has a legal obligation to regulate greenhouse gas emissions from existing power plants because it has been proven that greenhouse gas emissions endanger public health and welfare.

To meet these obligations the Environmental Protection Agency produced a Clean Power Plan, which established state-based emissions goals for fossil fired power plants. At the time it was finalized in 2015, it was estimated that the Clean Power Plan would decrease carbon dioxide emissions by 19% below business-as-usual level by 2030. However, Trump’s arrival in the White House forced a shake-up of many environmental plans, including the Clean Power Plan. Last August the Environmental Protection Agency released its proposed replacement for the Clean Power Plan: the Affordable Clean Energy rule.

Amelia Keyes from Resources for the Future, an independent non-profit research institution in Washington DC, and colleagues investigated the difference in impact that the Affordable Clean Energy rule will bring. Using the Environmental Protection Agency’s policy scenario modelling, along with projections of fuel generation and emissions datasets for all the different states, the team estimated carbon dioxide emissions up to the year 2030 under three scenarios: with the Clean Power Plan in place, with the Affordable Clean Energy rule in place and with no plan in place.

The researchers show that because the Affordable Clean Energy rule reduces the emissions intensity of individual power plants, it is likely to make coal-power a more popular choice.

“It may also extend the lifetime of some coal plants and allow them to retire later, thus causing a greater number of coal plants to remain in operation,” says Keyes. This counterintuitive impact is known as the emissions rebound effect.

Currently the US produces around 27% of its electricity from coal. With the Affordable Clean Energy rule in place, Keyes and colleagues estimate that the US will produce 22.3% of its electricity from coal by 2030. With no policy in place that would fall to 21.4%, and with the Clean Power Plan in place coal power would make up 19.7% by 2030. In other words, the Affordable Clean Energy rule is not just less effective than the Clean Power Plan, but is actively worse than doing nothing, acting to slow the progress of weaning the US off fossil fuels.

It isn’t just carbon dioxide emissions that are a problem. Air quality will also take a hit, with emissions of sulphur dioxide projected to increase by up to 148% in 19 states and nitrogen oxide estimated to increase by up to 9% in 20 states plus DC by 2030 under the Affordable Clean Energy rule, compared to no policy.

“Our results demonstrate the importance of considering the emissions rebound effect…in evaluating the Affordable Clean Energy rule and similar policies targeting heat rate improvements,” the authors write in ERL.

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