Publications

National accounts—which measure a country’s aggregate economic activity, including Gross Domestic Product (GDP)—largely ignore natural capital and ecosystem services. This omission occurs because national accounts heavily rely on market transactions to identify and value economic activity, whereas ecosystems’ contributions occur most commonly outside markets. This leads governments, businesses, and decisionmakers to ignore or misidentify some sources and uses of their income and wealth, skewing their decisionmaking. Recognizing these shortcomings, many countries, including the United States, are increasingly moving towards Natural Capital Accounting (NCA), a system of measuring natural capital and ecosystem services in a way that allows for their integration with national accounts. In this report, we provide an overview of NCA for non-economists.

In December 2023, EPA finalized updated values for the social cost of greenhouse gases (SC-GHG), following public comment and expert peer review. The agency derived these estimates using the best available science and economics, and the estimates represent a significant step forward in our ability to properly value climate effects. The brief is intended to introduce policymakers and practitioners to the SC-GHG, break down EPA's updated values, and explain why they represent a powerful tool that can streamline decisionmaking and policy analysis.

In May 2023, EPA proposed new limits for greenhouse gas (GHG) emissions from certain fossil-fuel-fired power plants under Section 111 of the Clean Air Act. Some critics have suggested that EPA’s new rule triggers the major questions doctrine. Under that doctrine, a court should look skeptically on the agency action in extraordinary cases involving unprecedented and transformative applications of agency authority. But the major questions doctrine is inapplicable to EPA’s use of CCS in its proposed regulations. Rather than propose a new approach that would transform its exercise of statutory authority, EPA has embraced one of its most traditional and well-established regulatory practices: setting emission limits based on pollution controls that cause a regulated source to operate more cleanly. This policy brief details why EPA’s latest proposal to limit GHG emissions from power plants fits neatly within the bounds of the legal authority left intact after West Virginia. It then explains how states and operators retain flexibility to use emission trading and averaging programs to implement EPA’s regulations.

In May 2023, the Environmental Protection Agency (EPA) proposed new limits for greenhouse gas (GHG) emissions from certain fossil-fuel-fired power plants under Section 111 of the Clean Air Act. Section 111 requires EPA to set limits reflecting the emission reductions achievable by applying what the agency determines to be the “best system of emission reduction” (BSER) that “has been adequately demonstrated,” and that meets certain other statutory factors. This policy brief summarizes the legal framework of Section 111 (including the legislative history and caselaw relevant to understanding its technology-forcing nature), walks through how courts have interpreted “adequately demonstrated,” reviews EPA’s past use of Section 111 to drive technology improvements, and explains why a potential Supreme Court decision that eliminates or curtails Chevron deference (a legal doctrine providing deference to reasonable agency interpretations of ambiguous statutory language) would not affect the longstanding interpretation of “adequately demonstrated.”

In May 2023, EPA proposed new limits for carbon dioxide emissions from fossil fuel-fired power plants. The proposed rule reflects a decade of careful development from EPA and embraces an approach consistent with the Supreme Court’s ruling in West Virginia v. EPA. In order to follow that approach, EPA based the limits for certain natural gas-fired turbines on the emission reductions achievable through hydrogen co-firing (i.e., burning a blend of natural gas and hydrogen). Unlike fossil fuels, hydrogen does not release CO2 when burned, but producing hydrogen can cause significant greenhouse gas (GHG) emissions depending on how its produced. Given these potential emissions, it is important to consider what type of hydrogen a power plant will co-fire with—otherwise this approach to reducing emissions could exacerbate climate change. This report explains the role of hydrogen co-firing in EPA’s proposed rule, discusses how EPA should design its final rules to achieve the specified GHG-reduction goals, and highlights additional actions that EPA and other regulators can take to further minimize the emissions (and the resulting climate harm) from hydrogen co-firing.