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Greenhouse Gas Reporting Program (GHGRP)

GHGRP 2018: Emissions by GHG

Carbon dioxide is the GHG emitted in the largest quantities. The 2.71 billion metric tons of CO2 reported for 2018 represent 90.9 percent of the GHGs reported in 2018a.  Methane emissions represent 7.6 percent of reported 2018 GHG emissions, N2O represents 1.0 percent, and fluorinated gases (HFCs, PFCs, SF6) represent 0.5 percent (Figure 1).

aThe Inventory of U.S. Greenhouse Gas Emissions And Sinks for 2018 is not yet available. In 2017, CO2 represented 82 percent of total U.S. GHG emissions.

Figure 1: Direct Emissions by GHG (2018)


The table below lists the primary sectors emitting each GHG.

Table 1: Largest Sources of GHG Emissions
Greenhouse Gas Source Categories Contributing Most to Emissions1 Sectors Contributing Most to Emissions
CO2 Electricity Generation (D), Stationary Combustion (C) Power Plants, Petroleum and Natural Gas Systems
CH4 Petroleum & Natural Gas Systems (W), Municipal Landfills (HH) Waste, Petroleum and Natural Gas Systems
N2O Adipic Acid Production (E), Nitric Acid Production (V), Electricity Generation (D) Chemicals, Power Plants
SF6 SF6 from Electrical Equipment (DD), Electronics Manufacturing (I) Other, Metals
NF3 Electronics Manufacturers (I), Fluorinated Gas Production (L) Other, Chemicals
HFCs HCFC–22 Production and HFC–23 Destruction (O), Fluorinated Gas Production (L) Chemicals, Other
PFCs Electronics Manufacturers (I), Fluorinated Gas Production (L) Other, Metals, Chemicals

1 These source categories account for 75 percent or more of the reported emissions of the corresponding GHG. The subpart under which the emissions were reported is shown in parentheses.