On January 11, 2012, EPA launched a new online data publication tool that provides the public with information on reported greenhouse gas (GHG) emissions in 2010.   The database currently covers nine industry groups, including 29 source categories, that directly emit large quantities of GHGs, as well as suppliers of certain fossil fuels and high global–warming-potential gases.  Power plants, petroleum refineries, and chemical plants were the largest sources of emissions required to report. As mandatory GHG reporting expands to more sources, the data from these will be made available in the online tool.

The original Mandatory Greenhouse Gas Reporting Rule was finalized on October 30, 2009, pursuant to authority under the FY2008 Consolidated Appropriations Act.  On November 19, 2011, EPA finalized a revised version of the rule, delaying reporting of 2010 GHG emissions data for several source categories from March 31, 2012, to September 28, 2012, in line with the reporting deadline for 2011 emissions data.