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Voluntary Reporting of Greenhouse Gases Program

What are Greenhouse Gases?

Many chemical compounds found in the Earth’s atmosphere act as “greenhouse gases.” These gases allow sunlight to enter the atmosphere freely. When sunlight strikes the Earth’s surface, some of it is reflected back towards space as infrared radiation (heat). Greenhouse gases absorb this infrared radiation and trap the heat in the atmosphere.

Many gases exhibit these “greenhouse” properties. Some of them occur in nature (water vapor, carbon dioxide, methane, and nitrous oxide), while others are exclusively human-made (like industrial fluorinated gases such as hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride).

The Greenhouse Effect

Concentrations of several important greenhouse gases have increased by about 33 percent since large-scale industrialization began around 150 years ago. Currently, about 75 percent of human-made carbon dioxide emissions are from burning fossil fuels.

This rapid increase in greenhouse gas concentrations within the lower levels of the atmosphere traps infrared radiation that would otherwise escape into space, and subsequent re-radiation of some of the energy back to the Earth maintains higher surface temperatures than would occur if the gases were absent.

Climate Change

Assessments generally suggest that the Earth’s climate has warmed over the past century and that human activity affecting the atmosphere is very likely an important driving factor. The global average surface temperature has risen by about 1.0 to 1.7 degrees Fahrenheit over the past century. Rising temperatures may produce changes in weather, sea levels, and land use patterns, commonly referred to as “climate change.”

Gases Covered By the Voluntary Reporting Program

The General Guidelines prescribe that reporting entities may report their emissions of the following gases:

  • Carbon Dioxide (CO2)
  • Methane (CH4)
  • Nitrous Oxide (N2O)
  • Sulfur Hexafluoride (SF6)
  • Perfluorocarbons (PFCs)
  • Hydrofluorocarbons (HFCs)
  • Chlorofluorocarbons (CFCs) and other gases (for reporting but not registering)

PFCs, HFCs, and CFCs are not individual gases, but groups of gases. For reporting purposes, Program participants should report emissions of PFCs and HFCs from this list. CFCs and other gases include gases and particles that have been demonstrated to have significant, quantifiable climate forcing effects when released to the atmosphere in significant quantities and for which DOE has established or approved methods for estimating emissions and reductions. Reductions of CFCs and other gases may be reported but not registered to the 1605(b) Program.

Review the Technical Guidelines for more detailed information about the gases covered by the Voluntary Reporting of Greenhouse Gases Program.

Additional Information

For more information about greenhouse gases and climate change, please see the pamphlet Greenhouse Gases, Climate Change, and Energy.




Voluntary Reporting of Greenhouse Gases.  Need help, contact the National Energy Information Center at 202-586-8800.

the 1605(b) Program