The problem with methane
Methane (CH4) is a naturally occurring gas found in the ground and ocean floor. As the main component of natural gas, it’s widely used across the globe to generate electricity, power industries and heat homes. The problem is that methane is perhaps a worse contributor to global warming than carbon dioxide.
This is because methane is much more efficient at trapping radiation. So, even though methane’s lifetime in the atmosphere is much shorter, its impact on global warming is around 28 times greater than carbon dioxide over a 100-year period.
According to the US Environment Protection Agency, the number one cause of methane emissions from human activities is from agriculture – mainly from the digestive process of domestic livestock, such as cattle and pigs. (Cattle flatulence may not sound like a human activity, but because these animals are raised for food and other products, the emissions are considered human-related.)
The number two cause of methane emissions is oil & gas production.
Today, oil & gas operations account for around 15% of total energy-related methane emissions globally, the equivalent of 5.1 billion tonnes of greenhouse gas. To put this into perspective, the two main fossil fuel fields in Turkmenistan leaked 4.4 million tonnes of methane in 2022, the equivalent of 336 million tonnes of CO2 and more than the entire carbon emissions of the UK combined.
Unsurprisingly, reducing scope 1 & 2 methane emissions from oil & gas production is now a top priority.
The International Energy Agency (IEA) has outlined a plan to halve greenhouse gas emissions by 2030. If the plan is to be realised, oil & gas producers must significantly reduce their scope 1 & 2 methane emissions by the end of this decade. Scope 1 covers direct emissions from owned or controlled sources, while Scope 2 covers indirect emissions from the generation of purchased energy.
Why is methane such an issue? And what can oil & gas producers do about it?
Tackling methane emissions
In the IEA’s Net Zero Emissions by 2050 Scenario, the emissions intensity of oil & gas operations must fall by 50% by the end of 2030. This may seem like a lot, but according to the IEA, tackling scope 1 & 2 emissions from oil & gas is one of the most viable and lowest cost options to reduce total greenhouse gas emissions – from any human activity – by 2030.
So, how does the IEA propose that this reduction is achieved?
The IEA outlines a series of ready-to-implement measures, with methane emissions at the top of the list. The IEA estimates that implementing these measures would require an investment of around USD 600 billion. However, this investment should have short payback period, as the saved methane can be stored and sold.
IEA measure to reduce greenhouse gas emissions in the oil & gas industry:
- Tackling methane emissions
- Eliminating all non-emergency flaring
- Electrifying upstream facilities using low-emissions electricity
- Equipping oil & gas processes with carbon capture, utilisation, and storage technologies
- Expanding the use of hydrogen from low-emissions electrolysis in refineries
Dealing with fugitive emissions.
Other areas to help reduce methane emissions is to deal with Fugitive emissions. These are small leaks emanating from valves or other equipment used in drilling and production.
In gate valves the major leak pathways are either from the stem packing or via the flange. If the stem packing is leaking, then a proven valve sealant could be used to stop this until corrective maintenance is performed.
It’s good to know that some things can be managed simply, quickly and at low cost!
In a gate valve, the main leak-to-atmosphere routes are via the stem packing, or the via the flange connections to other gate valves, the tree cross or wellhead.