EPA released the final version of its 2018 Greenhouse Gas Inventory (GHGI) on Thursday, and the latest government data clearly show that methane emissions from U.S. oil and natural gas systems continue to decline even as production skyrockets. From the report:

“Methane emissions from natural gas systems and petroleum systems (combined here) decreased from 235.0 [million metric ton CO2 equivalent (MMT CO 2 Eq.)] in 1990 to 202.1 MMT CO 2 Eq. in 2016 (32.8 MMT CO 2 Eq. or 14.0 percent decrease from 1990 to 2016).”

The 32.8 mmt in oil and natural gas methane emission declines from 1990 to 2016 have come at the same time that natural gas and oil production increased 50 and 21 percent, respectively.

The latest EPA data also show that combined oil and natural gas system methane emissions have declined three percent since 2005. Oil and natural gas production has increased 71 and 48 percent, respectively, during that time period, thanks largely to advances in hydraulic fracturing and horizontal drilling technologies.

As the above EPA chart shows, natural gas system methane emissions have decreased both in the short term and long term — declining 1.7 percent from 2015 to 2016 and more than 16 percent since 1990. From the GHGI:

“Natural gas systems CH 4 emissions decreased by 31.6 MMT CO 2 Eq. (16.2 percent) since 1990, largely due to a decrease in emissions from distribution, transmission and storage, processing, and exploration…”

Notably, the EPA reports that petroleum system emissions have decreased since 1990 due largely to decreased venting and flaring.

“…Petroleum systems CH 4 emissions decreased by 1.2 MMT CO 2 Eq. (or 3.0 percent) since 1990. This decrease is due primarily to decreases in tank emissions and associated gas venting.”

EPA data show that emissions from associated gas venting and flaring decreased by 36 percent from 2015 to 2016. Notably, venting and flaring emissions have been revised downward dramatically across the board from what was reported in last year’s GHGI.


The EPA notes in its report that petroleum system methane emissions have been significantly downwardly revised for each year going back to 1990 “relative to the estimate provided in the previous Inventory” due “primarily” to the “recalculation of associated gas venting and flaring emissions using a basin-level approach.”

EID will take a deeper dive into this and other notable methodological revisions in the coming weeks.

The final 2018 GHGI also shows that overall greenhouse gas emissions and carbon dioxide emissions continue to decline in the United States. As the following chart shows, overall greenhouse gas emissions declined 2.5 percent from 2015 to 2016.

EPA partially credited these continued declines to increased natural gas use in the electricity generation sector:

“Recently, a decrease in the carbon intensity of the mix of fuels consumed to generate electricity has occurred due to a decrease in coal consumption, increased natural gas consumption, and increased reliance on non-fossil generation sources. Including all electricity generation modes, electric power sector generators used natural gas for approximately 34 percent of their total energy requirements in 2016.”

“[T]otal emissions from the electric power sector decreased by 4.7 percent from 2015 to 2016 due to changes in the consumption of coal and natural gas for electric power, which were driven by changes in their relative prices.”

Overall U.S. carbon emissions fell two percent from 2015 to 2016 and are down 13 percent since 2005, according to EPA data.

These continued declines are largely due to the fact that power sector carbon emissions (1,809.3 mmt) are at their lowest levels since the GHGI debuted in 1990. In fact, as EID has previously reported, power sector carbon emissions are at their lowest levels since 1988 and the Energy Information Administration has credited roughly two-thirds of power-sector carbon reductions since 2005 to fuel switching to natural gas.

The continued GHG reductions detailed in this EPA report have come at the same time domestic oil and natural gas production has surged toward record levels, providing further evidence that the United States can develop the incredible energy resources that have been unlocked by fracking in an environmentally friendly fashion.