The electrical equipment manufacturers and use sector emits sulfur hexafluoride (SF6) and perfluorocarbons (PFCs) from the manufacture, refurbishment, and use of electric transmission and distribution equipment. SF6 and PFCs are used as electrical insulators and interrupters in electricity transmission and distribution equipment. The reported emissions from this sector decreased from 4.3 MMT CO2e in 2011 to 2.6 MMT CO2e in 2019, a decrease of 40 percent. The emissions have varied from a high of 4.3 MMT CO2e in 2011 to a low of 2.5 MMT CO2e in 2018. However, the largest decreases in emissions occurred in 2012 and 2015 when emissions dropped by 21 percent and 24 percent, respectively. The 2019 emissions increased about 0.1 MMT CO2e (4 percent) over those reported in 2018.
Most of the emissions for this sector come from the use of electric transmission and distribution equipment, rather than from equipment manufacturing and refurbishment. The CO2e emissions from the use of electric transmission and distribution equipment account for over 90 percent of the total annual emissions for this sector. The emissions originate from fugitive equipment leaks; equipment installation, servicing, decommissioning and disposal; and storage cylinders. Although PFCs and other fluorinated F-GHGs may also be used, SF6 is emitted in the highest volumes.
The decrease in emissions observed for this sector between 2011 and 2019 is likely driven by electric utilities replacing leaking equipment. [1]
[1] Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2018. U.S. Environmental Protection Agency. April 12, 2018, page 4-135. EPA 430-R-20-002. Available at: https://www.epa.gov/sites/production/files/2020-04/documents/us-ghg-inventory-2020-main-text.pdf.