Transparency and Honesty in Energy Regulations Act of 2024

This bill prohibits federal agencies from using the "social cost of carbon" and related metrics (estimating climate damage costs from methane or nitrous oxide) when developing environmental regulations, guidance, or cost-benefit analyses. It directly affects agencies like the EPA that create rules on emissions, power plants, and air quality. The law requires agencies to stop relying on these specific climate cost estimates in all regulatory decisions starting upon enactment. Agencies must also report to Congress on past uses of these metrics within 120 days of the bill becoming law.