WASHINGTON—The overall US electricity sector has gotten much cleaner over the last decade, and that trend is being driven in large measure by the eastern United States. In the East, emissions of harmful air pollutants such as sulfur dioxide and nitrogen oxides are about a third of what they were a decade ago. Over the same time period, carbon emissions in the East fell by about 15 percent. Today, a new blog posted by Resources for the Future (RFF) takes a look at these trends, examining “The Sources of Decreasing US Electricity Sector Emissions.”
In the new post, RFF Senior Fellow Joshua Linn and Research Assistant Kristen McCormack state that understanding the cause of the reductions is vital. On one hand, those that support relaxing current clean air regulations point to high costs for the benefits produced. On the other hand, supporters of stronger regulations argue that the technological advances to meet regulatory requirements lead to greater energy efficiency and cleaner power production—including through cheaper natural gas and the growing use of renewable energy such as wind and solar power.
To identify the reasons behind the decline in electricity sector emissions that has been observed over the last decade, the authors define three broad factors: The first isolates the scale, or total amount, of fossil fuel–fired generation. The second factor represents the share of total generation that comes from each emitting unit. The third factor represents the emissions rate of each generating unit.
The authors note that, “Overall, changes in emissions rates explain most of the overall decline in sulfur dioxide and nitrogen oxides emissions. Because regulations are the primary driver of changes in emissions rates, this decomposition suggests that regulation, rather than changes in market forces such as the price of natural gas and cost of renewables, explains most of the emissions reductions over this period.”
However, the authors caution that this doesn’t mean that the costs of regulation have necessarily outweighed the benefits. They’ll return to this point in future blog posts.
Read the full blog post: The Sources of Decreasing US Electricity Sector Emissions.