New research from The University of Texas at Austin finds industrial buildout in oil, gas and petrochemical sectors in the U.S. Gulf Coast and Southwest regions could generate more than half a billion tons of additional greenhouse gas emissions per year by 2030. That figure is equivalent to 8% of total current annual U.S. emissions. These emissions are driven by the regions’ oil and gas boom, and a substantial fraction comes from large industrial facilities such as new petrochemical plants, liquefied natural gas export terminals and refineries. The vast majority of these emissions will come from Texas and Louisiana.

The paper detailing the study, “Emissions in the Stream: Estimating the Greenhouse Gas Impacts of an Oil and Gas Boom,” was published this week in Environmental Research Letters.

This study comes on the heels of a new report from the Environmental Integrity Project (EIP), which finds that industry buildout in addition to drilling could release up to 227 million tons of greenhouse gas emissions by 2025. Although the EIP report’s findings are based on permitted emissions, UT researchers accounted for future permitted and nonpermitted emissions through 2030.

“We wanted to understand if the industrial buildout we were reading about was a greenhouse gas mountain or a molehill,” said Andrew Waxman, assistant professor of economics and public policy at the LBJ School of Public Affairs at UT Austin and a co-author of the study. “Emissions from oil and gas production are well known, but our analysis finds over two-thirds of future emissions will come from midstream and downstream sources, including petrochemicals, liquefied natural gas export facilities and refineries. These sources are a pretty big mountain that policymakers and climate modelers don’t seem to be currently accounting for.”

By 2030, the study finds that 541 million tons of additional CO2e* could be emitted each year from the industrial facilities and infrastructure projects that have been recently constructed, are under construction, are permitted to be constructed or are nonpermitted facilities in the Gulf region. These emissions are just from on-site combustion and do not include tailpipe or other end-use emissions.

*CO2e is a measure used to compare the global warming potential of various greenhouse gases by converting amounts of other gases to the equivalent amount of carbon dioxide.

These emissions represent more than 8% of total current annual U.S. greenhouse gas emissions and are about equal to the emissions from 131 coal-fired power plants.

“If these projects move forward without mechanisms to reduce their GHG emissions, reducing U.S. emissions may become even more difficult,” Waxman explained.

Petrochemical facilities (40%) are the largest source of the new emissions. Emissions from liquified natural gas (LNG) represent about 20%, and 22% of the projected emissions will come from facilities that are already built or under construction.

“Our methodology was a simple analysis based on publicly available data, and we were surprised by the large amount of emissions from these industrial sources that don’t get a lot of attention, such as ethane crackers and LNG terminals,” said Benjamin Leibowicz, a professor at UT Austin and a co-author of the study. “These facilities may operate for decades, so it’s critical that we understand the long-term impact they will have on the country’s greenhouse gas emissions, and that’s why a second phase of this work will address solutions to reduce these emissions.”

Several papers and media stories during the past decade have examined the rate and quantity of emissions from oil and gas production facilities, known as upstream emissions. Midstream and downstream emissions, however, including those from petrochemical facilities, liquefied natural gas terminals and refineries, are less understood. Based on data from permits, emissions factors, and facility capacities, the authors calculated likely emissions from midstream and downstream sources along the Gulf Coast that will be built as a result of increased oil and gas production in the region.

Construction projects in other regions where oil and gas production has increased in recent years – in the Appalachia and Great Plains areas, for example – were not included in this analysis.

The study was funded by the Cynthia and George Mitchell Foundation. A second phase of research will examine policy and technical solutions that could reduce these projected emissions.