A research team from Queen Mary University of London is the first to demonstrate the possibility of measuring total GHG emissions from LNG carriers.
Furthering the scientific understanding of GHG emission profiles
The results released today – 14 June 2022 – from this groundbreaking study quantify greenhouse gas (GHG) emissions from liquefied natural gas (LNG) carriers, thus providing actionable data for the LNG shipping industry on methane emissions. The study, led by Queen Mary University of London (QMUL), furthers a scientific understanding of GHG emission profiles of LNG carriers to meet national and international climate targets and corporate climate strategies.
In 2021, a team of scientists from QMUL and SLR Consultants took direct measurements onboard the Cheniere-chartered GasLog Galveston for a roundtrip voyage from Cheniere’s Corpus Christi liquefaction facility to a discharge port in Europe. Researchers were sure to consider all sources of methane and CO2 emissions, including engine exhausts, venting, and fugitive emissions. Additionally, this research also demonstrates the best methods to directly measure methane emissions from LNG carriers for future studies or retrofitting on-board continuous emissions monitors.
The results and recommendations were published today following peer-review in the journal Environmental Science and Technology (American Chemical Society) and include:
- CO2 emissions were lower than what other studies have assumed while venting, and fugitive emissions of methane were also extremely low;
- Uncombusted methane emissions from the engine exhaust were in line with manufacturers’ test data, but higher than other studies due to higher methane slip from the generator (non-propulsion) engines;
- These engine methane slip emissions can be reduced drastically (as much as by half) by operating the engines at higher loads. The study noted that this was the Galveston’s second voyage, multiple engines were utilised at lower loads for operational reasons, and carriers often utilise engines at higher loads; and
- The study recommends the installation of methane emissions monitors on engine exhausts to observe and report more accurate methane emissions estimates and to support methane mitigation operational practices.
“This study helps to fill a big data gap when it comes to methane emissions from LNG shipping. It is vital that we understand what their emissions profile is at a time when LNG imports are likely to grow substantially to reduce Europe’s reliance on Russian gas,” explained Dr Paul Balcombe, the Principal Investigator and lecturer in Chemical Engineering and Renewable Energy at QMUL.
“This study is the first-of-a-kind to measure total methane emissions from engines aboard LNG carriers, including venting and fugitive emissions, but we need to do much more to get a representative sample of the approximately 600-strong LNG fleet. As well as these academic measurement studies, increased monitoring of emissions from engines, vents and fugitives would allow us to identify and implement effective reduction measures as hotspots are found.”
Supporting climate action and guiding mitigation strategies
“This study provides actionable recommendations to monitor and reduce LNG shipping emissions to further strengthen the climate benefits of LNG. Following the recommendations of the study, Cheniere is expanding our emissions monitoring on the majority of our chartered carriers to further put this science into action. We appreciate the work done by CAMS, QMUL, and GasLog to help deliver data-driven transparency that can guide mitigation strategies,” added Fiji George, Cheniere’s Senior Director for Climate and Sustainability.
“Gaslog is committed to supporting climate action and is investing in partnerships, research, and development to achieve this. GHG and air emissions reduction is a priority for us, as reflected in our ESG focus areas; we therefore enthusiastically joined this initiative aiming to better understand and monitor methane emissions from LNG carriers,” concluded Kostas Karathanos, Gaslog’s COO.
“The industry needs similar studies to gather concrete data and establish confidence in the operational emissions. This is essential in determining impactful mitigating measures and pursuing realistic reduction targets.”
The study was funded by Enagas SA and CAMS (Collaboratory to Advance Methane Science), a research collaboration on methane science directed by some of the world’s top leaders in energy development and administered by GTI Energy, a leading research, development, and training organisation.
