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.
| 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.