McDermott: net zero LNG is a realistic goal [LNG2023]
Q: Is net-zero LNG a realistically attainable goal and how should the industry best work towards it?
A: Net-zero LNG is a realistic goal but to ensure credibility, the LNG industry should address the complete value chain from upstream through to end user. Achieving net-zero across parts of the LNG value chain is attainable but is challenging across the entire value chain. The following points can be made for each element of the LNG value chain, noting that approximately 75% of the GHG emissions would result at the end user.
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Upstream: Achieving net-zero emissions on the upstream side is challenging and dependent on the source of the natural gas, whether onshore, offshore, through conventional drilling or fracking. There are multiple initiatives in place to reduce emissions, from electrification of production facilities using renewable energy through to detection of, and elimination of, fugitive emissions.
LNG Liquefaction: There are multiple ways to reduce emissions from LNG liquefaction facilities. The use of electrically driven compressors, taking power from renewable sources, has the largest impact, enabling an 80%-90% reduction in GHG emissions when compared to a traditional industrial gas turbine driver configuration utilised by most of the world’s LNG facilities. The majority of the remaining emissions can be mitigated through design features that limit flaring during trips/start-ups and sequestration of the CO2 that is removed from the feed gas. A small amount of difficult-to-eliminate emissions would need to be offset by carbon credits.
LNG Transport: There have been many advances in emission reduction from LNG carriers including efficiency improvements in ship design and engine technology as well as reductions in venting and fugitive emissions of methane. To achieve net-zero, offsets through carbon credits would be required.
LNG Regasification: LNG regasification facilities have a limited energy requirement. Use of heat from ambient sources, air, water, or utilization of waste heat from nearby industries, can bring the emissions to near zero with the final small, and often intermittent, emissions offset by carbon credits.
End User: This becomes industry and end user specific, but in general, to achieve a net-zero scenario will require carbon capture with sequestration plus an element of offset using carbon credits.
Q: What developments are we seeing in the area of addressing methane emissions at LNG facilities?
A: In general, methane emissions are very low on existing LNG facilities due to an increased use of welding of piping rather than the use of flanges. There is increasingly more focus on the source of methane emissions and implementation of schemes to reduce, and if possible eliminate, such emissions through implementing seal gas recovery systems and reduced emission valve glands into designs. There is also increased focus on reducing operational flaring, whether due to normal operation, shut down, start up, and non-routine emissions. For owners and operators there are opportunities on the operation and maintenance side of the LNG facility to implement increased frequency of leak detection and repair (LDAR) programs. More advanced detection systems such as infrared cameras and laser-based detectors are being deployed to make LDAR programs more efficient and effective.
Q: What are the main benefits of the modularization approach and are we seeing the industry adopt it more, and if so why?
A: The prime drivers to adopt a modularization approach are:
Labor Cost: This is a benefit if module fabrication facility labor costs are lower than field labor costs, especially when the infrastructure required to support crews in the field is considered.
Productivity: Module fabrication facilities have a stable workforce, well proven standards, procedures and assembly-line techniques that add to the overall efficiency of the fabrication process. The work in the fabrication facility is performed in a covered and/or environmentally controlled environment. This eliminates the loss of productivity due to wind, rain, flooding, lightning, etc.
Equipment: With proper work scheduling and sequencing, a modularization approach can allow for reduced on-site costs due to a reduced requirement of equipment in the field.
Safety : Shifting work into a controlled fabrication facility environment generally benefits the overall safety risks of a project.
Reduction of Peak Workloads: Modularisation reduces the amount of direct and indirect field labor. This can be an important factor in projects that are competing for resources with other projects or simply are limited in local resources. Cost can be saved due to reduction in size of temporary facilities, camps, transport of workers, food, water, housing, medical needs, and recreation facilities at the jobsite.
Schedule: On projects that are hampered by a lengthy permitting process, modularization can effectively allow construction to begin months earlier in the fabrication facility. Once the permit is acquired, modules can be set much quicker than the time required for onsite fabrication and assembly. The LNG industry is seeing an increasing focus on implementing a modular execution strategy, primarily as this provides greater certainty on project delivery, both on cost and schedule. This reduces the uncertainties that are not often under the total control of the EPC contractor, whether these are political, social, or climate influenced events.
Q: In what ways is this modularization approach evolving?
A: The early module concepts in the LNG industry were often based on stick built layouts which resulted in a missed opportunity of greater reduction for site based activities relating to hook up, installation and commissioning. Subsequent modular LNG designs were developed for the early Floating LNG projects. Again, these had specific constraints, whether due to marinization requirements or limits on available footprint with resulting safety/hazard implications.
In recent years the LNG industry is moving to modules in the 1000-10,000-te size range, based on an increased degree of standardisation and repeatability of the module design. It is also developing modules on a system basis thereby minimising site hook up and commissioning activities.
This interview was originally published in the LNG2023 Daily, produced by NGW during the LNG2023 conference in Vancouver July 10-13.