ALEX KOLKER, PhD

Alexander S. Kolker, PhD

What else do we know about Louisiana’s greenhouse gases, where they come from, and how they are changing over time? Recently, this blog pointed out that many of the state’s largest greenhouse gas emitters come from just a few areas- a corridor along the Mississippi River, the Lake Charles region, and a mixture of spots along the Red River.

There is more to learn about how emissions have changed over the past decade. As Louisiana develops plans to reduce greenhouse gas emissions, it helps to have a deeper understanding of the sources of these emissions, and the trends that are driven changes in the state’s emissions patterns.

One useful source is the US Environmental Protection Agency’s (EPA) database of emissions from large facilities. EPA refers to this database as, “FLIGHT”, which come from its’ name as the Facility Level Greenhouse Gas Emissions Tool. You can find that database here. https://ghgdata.epa.gov/ghgp/main.do. This source contains data on greenhouse gas emissions that companies report to EPA, expressed in terms of the tons of carbon-dioxide emitted, or the equivalent heat trapping power of other greenhouse gases like methane or nitrous oxide. This value is typically written as CO₂e. 

Since facilities account for over 50% of Louisiana’s emissions, the FLIGHT database is a good guide to statewide trends and patterns. The FLIGHT database does not provide every source, and emissions from cars, homes, some small business, and the agricultural sector are not here. The FLIGHT database is also self reported data- if the company misses a leak, or misreports data, that error would be reflected in the data. Short story, the FLIGHT database provides an useful, but not fully complete picture of Louisiana’s greenhouse gas emissions. 

Statewide, there is something of bow shaped pattern in quantity of emissions from large facilities. Louisiana-based facilities emitted about 144.6 million metric tons of CO2e in 2011. (This number include about 5 million metric tons of CO₂e  from the open Gulf of Mexico). These  emissions reached a low value 137 million metric tons of CO₂e in 2013, and then increased to  146.3 million metric tons of CO₂e in 2019- the most recent year for which data is available. 

This pattern reflects at least two contrasting trends. On one hand, there has been a shift away from coal and towards natural gas in the power sector, which results in reduced greenhouse emissions. At the same time, there has been an increase in industrial activities, and gas export facilities that contributed to increased greenhouse gas emissions. These contrasting trends are related: hydraulic fracturing (i.e. fracking), led to an increase in domestic supplies of oil gas, facilitating the shift from coal to gas. Fracking also increased domestic oil and gas supplies, which contributed increased industrialization, and allowed for the United States’ development as an oil and gas exporter. 

Many of these facilities are located in Louisiana- there is an extensive network of energy facilities here, and the Mississippi River and other waterways offer port access for ships that carry oil and gas. However, as others have pointed out more eloquently than this author- many of this facilities are located near communities of color, and poor communities.

We can see evidence of Louisiana hydrocarbon transitions by looking at trends from specific economic sectors. During the period from 2011 to 2019, emissions from power plants decreased from 53.4 million metric tons of CO₂e to 40.1 million metric tons of CO2e, reflecting a shift in fuels. At the same time, emissions from petroleum and natural gas systems increased from 16.2 to 22.8 million metric tons a year of CO₂e, while emissions from the chemical sector increased from 36.3 to 43.2 million metric tons CO₂e per year. These emissions from the chemical sector are large, they make up 23% of the 186 million metric tons of CO₂e that were emitted nationally by chemical sector in 2019. Interestingly, the refining sector stayed roughly flat during this period- it emitted 31.2 million metric tons of CO₂e in 2011; in 2019 that number was 31.6 million tons of CO₂e. 

We can see some examples of changes in the power sector by looking closely at greenhouse gas emissions from specific facilities. The Big Cajun 2 power plant in Pointe Coupee Parish decreased from 12.5 million metric tons of CO₂e in 2010 to 2.9 million metric tons in 2019. The Michoud Plant dropped from 1.2 million metric tons of CO₂e in 2010 to zero emission when it was shut down in 2016. However, as others have pointed out, the power from plant was made up for by an expansion of the Nine Mile power plant in Westwego. That plant saw its emissions increase from 2.8 million metric tons of CO₂e in 2010 to 4.6 million metric tons in 2019. One facility that experienced less overall change was Brame Energy Center in Red River parish. This coal fired plants has remained one of the state’s largest emitters- fluctuating between about 5.4 and 7.6 million metric tons CO2e between 2010 and  2019. 

We can also look at parish by parish patterns. Cameron parish experienced one of the most significant changes over the 2011 to 2019 time frame. This parish accounted for 364 thousand metric tons of CO₂e in 2011; by 2019 that value was 6.1 million metric tons of CO₂e. The vast majority of these releases came from one facility, the Sabine Pass LNG facility, which exports natural gas made available by the fracking boom. With more export facilities coming online or planned, other coastal parishes could experience substantial increases in the future too. 

Southwest Louisiana also had one of the state’s largest emitting parishes, Calcasieu- which is home to Lake Charles’ large industrial facilities. This parish emitted 20.7 million metric tons of CO₂e in 2019, amounting to about 14% of the state’s total emissions from large facilities. Calcasieu parish also exhibit’s Louisiana’s bow shaped pattern of facility emissions, the parish emitted 21.3 million metric tons in 2011, reached a low of 18.4 million metric tons in 2016, and before increased to 20. 7 in 2020. Powerplants decrease from 8.5 million metric tons of CO₂e in 2011 to 5.6 million metric tons in 2019, while chemicals increased from 5.7 to 7.5 million metric tons.

Figure 2. Greenhouse gas emissions from facilities in St. Charles Parish. Source: https://ghgdata.epa.gov/ghgp/main.do

Some of the river parishes also experienced increases during the 2010’s. Emissions in St Charles Parish increased from 13.7 to 18.3 million metric tons of CO₂e, mostly from  increases in the power and chemical sectors. Ascension Parish also experienced an increase in emission – from 11.8 to 16.8 million metric tons of CO₂e between 2011 and 2019. Almost all of this parish’s increase came from the chemical sector. This river corridor also has parishes like St. James Parish. Here the overall trend was relatively flat, but that trend includes decreases from some facilities and increases in others- like the NUCOR steel plant.

There are of course more detailed trends that we can observe from the FLIGHT database, and it is a good thing that these data are available for the public to see. It does not address every question that people will want to know. For example, the database says nothing about other air quality hazards that might be emitted from these facilities. Understanding that question will take more research. But, in order to reduce Louisiana’s emissions to net zero by 2050, we need to understand where they come from, and this tool provides some free, publicly available insight to that question.  

-Alexander S. Kolker PhD

 I should also point that I am on the science advisory panel for the state’s climate initiative, and and I ams tasked with reviewing the state’s greenhouse gas inventory. As part of my review, I have spoken with Dr. Davis Dismukes who is the lead author of that report, and his knowledge of Louisiana’s emission has helped me better understand the information presented here. I would also like that Southwings for the opportunity take aerial photo that is the cover image for this piece. Any mistakes I have made here are my own.