Measuring Carbon Dioxide Emissions From Liquefied Natural Gas (LNG) Terminals With Imaging Spectroscopy

The rapid growth of liquefied natural gas (LNG) exports underscores the importance of CO2 monitoring for LNG export terminals. We present a method for measuring LNG terminal CO2 emissions using remote sensing imaging spectroscopy. The method is first validated using 47 power plant emission events with in situ measured data, then applied to 22 emission events in Sabine Pass and Cameron. The power plant data set shows a robust correlation between our estimates and in situ data, with R2 0.9146 and the average error -2%. At Sabine Pass, eight point sources are identified with emission rates from 219.69 +/- 54.95 to 1,083.22 +/- 308.06 t/hr. At Cameron, three point sources are identified with emission rates from 91.64 +/- 25.81 to 265.61 +/- 67.80 t/hr. The liquefaction carbon intensity estimates also align with past study ranges. This illustrates that remote sensing can validate environmental reporting and CO2 inventories for industrial facilities. The natural gas (NG) system is an important source of carbon dioxide (CO2) emissions. Rising U.S. NG production and international energy demand led to a rapid growth of liquefied natural gas (LNG) exports. This makes it increasingly important to assess the CO2 emissions along the LNG supply chain, especially during gas liquefaction at LNG export terminals. However, existing inventories only provide annual/monthly data for some major LNG terminals from operators, which lack measurement-based in situ validation. Here we introduce a top-down CO2 measuring method using remote sensing imaging spectroscopy, which can provide an independent third-party data source above the detection threshold with uniform measuring technology across all infrastructure. Additionally, the independent measurements from this method would help evaluate the magnitude and variation of existing emission inventories. When combined with remote sensing methane detection, it can further monitor the carbon emissions more efficiently along the NG supply chain. This could be achieved by retrieving atmospheric CO2 and CH4 simultaneously from the same remote sensing campaign. This study also shows the mapping and quantification capability of imaging spectroscopy on the plumes with emission rate of 100-3,000 t CO2/hr, implying a broader application potential in CO2 top-down detection. Twenty-Two CO2 emission events from Sabine Pass and Cameron liquefied natural gas (LNG) terminals are found and quantified by airborne imaging spectrometersImaging spectrometers are capable of measuring power plant CO2 emissions with relatively high agreement with in situ measured dataCompared to power plant, LNG terminal CO2 plumes are smaller in spatial extent, with lower emission rates and more background noise