We have implemented a wide range of technologies and processes to increase the efficiency of our operations and manage our Scope 1 and 2 GHG emissions. Our LNG facilities are our largest source of energy consumption and Scope 1 GHG emissions, primarily due to the power used for refrigerant turbines and thermal oxidizers. We are also working to manage emissions from our pipelines and offices.

We also regularly assess the efficiency of our operations and effectiveness of emissions reduction efforts, including comparisons to industry best practices and peer practices and performance. While we compare favorably to our peers in these assessments, we continue to focus on improving our emissions management efforts.

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Managing emissions at our LNG facilities

To achieve maximum possible thermal efficiency and minimize thermal losses and emissions, we have implemented several processes and technologies, including the following:

Liquefaction efficiency: Highly efficient Optimized Cascade® process used at SPL and CCL LNG facilities.

High-efficiency gas turbines: Aeroderivative gas turbines are more efficient than industrial turbines.

Electric drive compressors: Electric drive compressors at the CCL facility expansion are expected to result in greater efficiency and emission reduction than traditional gas-powered turbines.

Waste-heat recovery: LNG trains are equipped to capture waste heat from exhaust of refrigeration gas turbines and thermal oxidizers. Recovered heat is reused in other facility processes.

Floating roof tanks: Floating roof tanks on condensate tanks prevent the release of surface hydrocarbons.

Boil-off and ship-vapor recovery: Boil-off gas generated during normal operations and ship loading is captured and reused, redirecting it for re-liquefaction rather than flaring.

Half rate trip controls: Automated controls enhance plant stability, maximize production and minimize thermal stress and losses across diverse operating scenarios.

Maintenance plan improvements: Turnaround intervals have been extended by leveraging internal expertise and collaborations with key equipment providers, minimizing losses associated with planned activities.

Production optimization: Numerous production optimization activities have increased flexibility of LNG trains to distribute load across different refrigeration compressors. This approach further improves LNG train efficiency and contributes to reduction in specific power required to produce a unit of LNG.

Fin fans: Increase efficiency, reliability and production capacity of trains through increased and better distribution of airflow over exchangers. 

Managing methane emissions

While methane constitutes a small portion of our overall GHG emissions, we are focused on reducing methane emissions from our operations because of methane’s heightened near-term impact compared to CO2 emissions. Methane emissions primarily stem from leaks and flaring, prompting us to implement measures to address and reduce these emissions. In conjunction with the pipeline emissions-reduction initiatives outlined below, our targeted measures to curb methane emissions include:

Closed-loop cooling process: Closed-loop cooling process captures volatilized methane during the cooling process and redirects it back into the liquefaction process, eliminating the need to vent it into the atmosphere.

Leak detection and repair: Routine audio, visual and olfactory inspections and other leak detection and repair activities at our terminals and compressor stations detect fugitive emissions, particularly methane. Leak detection surveys are conducted across our operations on a quarterly to annual basis using techniques such as optical gas imaging cameras and Environmental Protection Agency Method. Our QMRV program supplements these leak detection surveys. Pressure safety valves are monitored to maximize operational reliability and minimize overpressure events, reducing methane emissions.

Compressed air valve control: Compressed air, instead of natural gas, is used to control valves and other equipment, reducing fugitive emissions.

Low- or no-bleed devices: Use of these devices at meter stations and control valves lowers emissions.

Pipe flange management: Specialized pipe flanges, coupled with ongoing inspections and maintenance, reduce potential fugitive emissions.

Managing emissions from flaring

We tailor our flare emission-reduction efforts to each facility’s unique designs and processes.

Active flare management: Skilled operators finely tune air in our liquefaction facilities during flaring events to optimize flare efficiency. 

Flare tip redesign: Flare tips at both our SPL and CCL liquefaction facilities have been redesigned, doubling their operational life and reducing flaring during flare tip replacements by 50%.

Seal gas recovery systems: Seal gas recovery systems have been installed on all large-scale trains at the CCL liquefaction facility and all SPL liquefaction facility compressors, reducing volume of refrigerant lost to flaring. 

Thermal oxidizer: Emissions from acid gas removal unit at all large-scale trains at the CCL liquefaction facility and at the SPL liquefaction facility as directed to a thermal oxidizer, reducing volume of gas routed to flare.

Exchanger cleaning: New exchanger cleaning process reduces the need for operational defrosting and associated flaring by 50%.

Increased temperature specifications: Processes have been implemented to allow increased temperature specifications for LNG ship loading operations, reducing need to flare off LNG vessels.

Managing emissions from our pipelines

We have implemented several measures to manage emissions throughout our pipeline operations.

Compressed-air pneumatic controllers: Compressor stations employ zero-emission compressed-air pneumatic controllers, rather than high-bleed natural gas pneumatic devices, on valves and other equipment to eliminate methane emissions.

Reducing maintenance and ​“blowdown” emissions: Operational lifespan of critical equipment is extended through strategic partnerships with major equipment providers, reducing maintenance shutdowns and associated emissions. Pipeline blowdowns (essential releases of gas to reduce pressure for maintenance, testing or other activities) have been reduced by keeping compressors pressurized post-shutdown for up to several days.

Low-NOx compressor engines: State-of-the-art compressor engines are used to drive pipeline compressors, limiting NOx emissions.

Managing emissions at our offices

Our headquarters in Houston and our office in Washington, D.C., are located in certified Leadership in Energy and Environmental Design (LEED) buildings. We use a range of energy-saving strategies in all our office buildings, including energy-efficient lighting and building management systems that minimize heating, ventilation and air conditioning (HVAC) use when our offices are closed. We also encourage employees to reduce their footprint by reimbursing those who opt to commute to our U.S. corporate offices via public transportation.

Managing supply chain emissions

We are working to further enhance industry transparency and improve performance by encouraging collaboration across our supply chain. Since 2018, Cheniere has focused on reducing methane emissions across our supply chain, including by co-founding the Collaboratory to Advance Methane Science (CAMS). Today, we are using our LCA and QMRV work to support our and our partners’ understanding of methane emissions sources. For example, our LCA illustrates that methane is a primary contributor to LNG’s GHG footprint in the upstream and midstream sectors. Reducing methane emissions, for example, through leak detection and maintenance, offers a strategic and cost-effective opportunity for reducing overall supply chain emissions.

In addition, we host an annual supplier sustainability workshop to promote best practices of methane management, and we work with suppliers to assess the emissions profile of our supply chain.

Managing emissions from LNG shipping

Cheniere Marketing (CMI) contracts a long-term chartered fleet to deliver LNG to customers who choose Delivered at Place gas. We improve chartered ship fleet fuel economy by focusing on efficiency, emissions management and transparent communication with customers and partners. CMI charters vessels equipped with the most efficient propulsion and containment systems and onboard reliquefaction/​subcooler units whenever feasible. Ongoing engagement with ship owners and shipyards includes workshops, emergency drills and collaboration on optimizing operational efficiency and emissions management.

XDF/MEGI/MEGA propulsion: CMI’s fleet features XDF/MEGI/MEGA propulsion technologies, the most efficient vessels available on the market. The new-build ships can run on fuel or boil-off LNG — LNG that warms back into a gas as a routine part of the transportation process — which has a significantly lower CO2 emissions profile than typical marine fuels. In addition, many of these new vessels are fitted with new technologies such as reliquefication units, which can reliquefy excess boil-off gas and inject it back into the containment system, and an air lubrication system, which injects air under the ship to create a continuous layer of bubbles between the hull and the seawater, reducing drag and further improving fuel efficiency.

Engineering improvements: We also invested in extra valves and piping to reduce emissions from gas-ups prior to delivery, the first in our industry to do so. These cargo piping modifications are aimed at reducing methane emissions associated with gas trials and gas-up procedures.

Emissions measurement technology: As part of our LCA and QMRV efforts, we have installed continuous emissions monitoring systems (CEMs) on the majority of CMI’s long-term charters. We will use these monitors to continue to expand the measurement of shipping emissions and help identify strategic mitigation activities.

Transparency: We also issue CE Tags to all long-term customers for transparent emissions information per cargo. These CE Tags are provided voluntarily to our customers and reflect emissions profiles based on peer-reviewed methods. Note that our CE Tags are not a claim of a specific ​“differentiated” or ​“certified” or ​“responsible” LNG product, nor has Cheniere transacted in commercialization of such products.