S. 2261 — Clean Shipping Act of 2025

This section establishes a marine vessel fuel carbon intensity standard under the Clean Air Act, requiring the EPA Administrator to promulgate regulations for vessels of 400 gross tons or more on covered voyages (i.e., commercial passenger or cargo transport between U.S. ports or between a U.S. port and a foreign port) to use fuel with carbon intensity (i.e., lifecycle greenhouse gas emissions per megajoule) that is (1) at least 30% less than the 2027 baseline in 2030-2034, (2) 58% less in 2034-2039, (3) 83% less in 2040-2044, (4) 92% less in 2045-2049, and (5) 100% less in 2050 and thereafter. If a required reduction is not technologically or economically feasible, the Administrator must instead set the maximum feasible reduction; the Administrator may harmonize with equal or stricter International Maritime Organization standards, exempt vessels on covered voyages 30 days or fewer per year, allow averaging across commonly owned or controlled vessels, and credit overcompliance toward future standards (with initial regulations due by January 1, 2029, and others two years prior). The section further requires the Administrator to develop a list of consistent monitoring methods (aligned with EU and IMO schemes) and mandates annual reporting by vessel owners or operators on fuel carbon intensity, usage, and total greenhouse gas emissions (in carbon dioxide-equivalent) for covered voyages, with an annual EPA report due 180 days after each period.

This section establishes zero-emission standards under Clean Air Act §213(e) for greenhouse gases and criteria air pollutants (i.e., those for which air quality criteria have been issued under CAA §108) from vessels at anchorage or berth in the U.S. contiguous zone. The EPA Administrator must promulgate such standards (or maximum technologically and economically feasible reductions if zero-emission standards are infeasible) by January 1, 2029, with full compliance required by January 1, 2035, considering net emission reductions and impacts on public health, safety, the environment, air quality, water quality, and solid waste.