Methane is a potent greenhouse gas and over the last two centuries its concentration in the atmosphere has more than doubled. There are numerous emission sources, varying from fossil fuel production to wetlands. Understanding the characteristics of these sources is of paramount importance for reducing the impacts of global warming and climate change. Our research focusses on the natural gas supply chain. We aim to improve the state of knowledge on emissions, develop approaches to monitor emissions and develop cost-effective strategies to reduce emissions.
Why Natural Gas?
Natural gas is increasingly being used as a transition fuel, replacing more carbon intensive fuels, on the way to a zero-carbon economy. However, a great deal of research is still needed to understand methane emissions from the oil and gas industry. Improvements are required in the methods for detecting, measuring and reducing emissions. This is vital as emissions could negate the benefits of fuel switching.
In recent years, leading oil and gas companies have increased their focus on emission reductions and some have pledged to be net-zero by 2050. Independent academic research is essential for providing transparent and robust understanding of the issue, and for determining the mitigation potential for different supply chain stages across the world.
Methane and Environment Programme (MEP)
The MEP was officially launched in May 2018. The programme was set up following the launch of the first White Paper ‘Methane and CO2 emissions from the natural gas supply chain’ and is led by Dr Adam Hawkes.
The aims of MEP are to improve our understanding of the methane emissions and how to reduce them most effectively; understand the pathways and what the limitations are to reducing emissions; and understand the role of natural gas in future lower carbon energy systems.
- Quantify the variation and distribution of emissions across different regions, routes, natural gas resources and processes.
- Improve emissions estimation methodologies and reduce uncertainties associated with emissions reporting.
- Work with industry and policy makers to develop cost-effective routes to mitigate emissions.
- Assess the impact of methane emissions on the climate, human health and on ecosystems.
Our research topics
Below are some key issues being addressed through the MEP:
Methane and climate metrics
What is methane’s contribution to climate change and the environment? Methane is a very strong climate forcer, with a global warming potential far greater than carbon dioxide, but it is relatively short-lived in the atmosphere. A gas’s effect on climate change depends on its concentration, how long it stays in the atmosphere, how much heat it traps and how it interacts in the atmosphere.
There are numerous ways to examine the greenhouse impact of gasses and several different climate metrics are used. No climate metric is fundamentally 'correct' with each having a specific role to play. Representing the effect of methane requires the correct use of these metrics. In addition to climate change, methane affects the creation of ground-level ozone which effects both human health and ecosystems.
The Sustainable Gas Institute's MEP is conducting research into methane’s climate and environmental impact, as well as exploring which metrics and timescales are most appropriate.
Uncertainty in methane emissions estimates
There are numerous ways to estimate emissions from the natural gas supply chain, ranging from handheld methane detectors to aircraft with spectrometers. However, the magnitude of emissions from the oil and gas sector remains disputed, varying across regions and varying according to the different estimation methods and assumptions used. Estimates of methane venting and leaks from the natural gas supply chain have been the subject of much controversy, due to the uncertainties in methods, data quality and assumptions used.
Many studies have estimated how much methane is emitted, but a variety of methods and techniques have been used making it difficult to make direct comparisons.
We have been working with companies to help robustly assess different estimation methods and are using probabilistic techniques to quantify total uncertainties in estimates of fugitive emissions.
The aim is to assess what we currently know and establish what we can do to reduce both the uncertainties and the emissions.
Methane emissions can occur at all stages of the supply chain. Emissions can be via vents, leaks and incomplete combustion and consequently there are a vast series of abatement options.
The programme analyses different supply chains to identify key hotspots in emissions. These hotspots may be a specific equipment type or even a super-emitter. Super-emitters are a small number of equipment or facilities which cause disproportionately large emissions. Detecting and managing super-emitters is an undeveloped area of research and offers potential for major reductions.
The MEP studies the environmental benefits and cost-effectiveness of implementing different emissions-reducing options and identifying a set of best technological option (BTO) scenarios for different regions and supply chains.
Filling the knowledge gaps
While much work has been done to identify and reduce methane emissions across industry, governments and academia, there are still large gaps in our knowledge in different regions, supply chain routes and processes.
The programme identifies these gaps and strives to provide evidence to fill them, by identifying key measurement requirements, or quantifying reductions through technology, technique or policy change.
The key roles of natural gas in lower carbon systems
Natural gas is a key fuel and feedstock for many uses relating to electricity, heat, transport and chemical production. As a fossil fuel, its unabated combustion must eventually diminish in a low carbon world, but there are a variety of potential innovative routes where it could play an important role in decarbonising systems. For example, natural gas could play a key role in low carbon hydrogen production, or blending with biogas.
We are assessing potential end-uses, technologies and decarbonisation options to determine the most important and effective roles of natural gas in future low-carbon energy systems. It is extremely important to assess not just the level of carbon dioxide reductions, but also other environmental, economic and social impacts, so that we don’t replace one problem with an even larger one.
Our current projects
- Methane and net zero- the role of negative emission technologies
With many oil and gas companies striving to be net-zero, methane becomes even more important. While emissions cannot be directly removed from the atmosphere, negative emissions technologies (NETs) could offer a way of offsetting methane emissions. We examine the role of NETs with the aims of quantifying the amount of NETs needed for the industry to be net-zero, as well as identify which NETs are more favourable for methane offsetting.
- Methane emissions from global supply chains
Methane is emitted from every stage of the oil and gas supply chain. While previous studies have estimated emissions from production/distribution, it is uncertain how emissions vary with supply chain route and how reliable the underlying emission data are. We aim to quantify methane emission from gas supply chains, considering all stages in the supply chain as well as assessing the emission factor data used in inventory reporting.
- LDAR strategies
Leak detection and remediation (LDAR) campaigns are crucial for identifying leaks and compiling accurate emission inventories for facilities along the gas supply chain. However, the frequency in campaigns, technologies used, and inventory recording varies. We assess the various LDAR strategy guidelines to draw comparisons and identify key components of successful LDAR campaigns.
- Comparing satellite data with inventory estimates of methane emissions from natural gas.
Methane emissions from across the natural gas supply chain are notoriously hard to accurately quantify. However, many countries require an inventory of estimated emissions from every emitting site over a threshold. There are various methods used to compile these inventories, ranging from emission factors to point source measurements. Many studies have attempted to assess the accuracy of these inventories with varying results. An emerging development in the quantification of emissions from oil and gas activities is the use of satellites. Satellites have great potential to quantify emissions, but research is needed to optimise their use.
This project uses the Sentinel 5P satellite’s TROPOMI instrument to measure emissions and directly compares these to inventory estimates in the Montney basin region of Canada. Possible shortcomings in both the inventory and satellite estimates are assessed and improvements are considered for both.
- Calculating the minimum detection limits of methane measuring satellites in North America
Satellites are continuing to grow in popularity and use in the detection and quantification of methane emissions in oil and gas supply chains. Few studies have been carried out that look into the minimum detection limits (MDLs) of satellites and what can affect them. These MDLs will vary day to day, region to region and can be reduced. A misunderstanding of MDLs will cause emissions to either go undetected, or be incorrectly attributed. A thorough understanding of what MDLs are under different conditions, alongside real life examples using Sentinel 5P data is the goal of this project. Once this is achieved a comparison to emission inventories for North America will be undertaken. From this a compressive list of what, with the current crop of satellites, emissions can be detected across North America. This will facilitate the correct usage of satellites to quantify and detect emissions in North America.
Publications and Impact
The Sustainable Gas Institute's research and expertise about methane has been used to guide decisions on reducing emission and a number of publications have been produced.