Methane emissions are rightly associated with global warming and the climate crisis in general. A recent report by the UN and CCAC suggested that reducing methane emissions by 45% by 2030 is critical for limiting global warming to 1.5°C.
This report gained significant media attention from the Guardian, Sky News, and the Financial Times, among other notable major news outlets.
Methane
But while the link between methane and global warming is clear to see, methane can indeed be repurposed and put to good use. Organizations that own the correct technology can generate power from methane emissions.
Not only will this help them use fewer fossil fuels, but they can also gain genuine environmental benefits from their apparently ‘harmful’ emissions.
Challenges
IEA has called flared gas a “wasted economic opportunity” releasing carbon and methane emissions
IEA has called flared gas a “wasted economic opportunity” releasing carbon and methane emissions into the atmosphere while wasting energy that could otherwise be put to good use.
Let’s explore why methane emissions are so problematic currently before explaining how companies can unlock methane’s hidden potential.
The problem as things stand
Methane emissions have never been higher. But where exactly are they coming from? Alongside ruminant animal and agriculture; oil and gas (O&G) operations and municipal solid waste (aka landfill sites) are the two other major sources of methane-related emissions.
145 billion cubic meters of gas per year are flared in O&G operations, in other words, the methane, released as part of oil extraction, is burned for safety reasons and converted into CO2. While the process emits CO2 rather than methane itself, this is just as harmful to the environment (as CO2 has a longer-lasting impact).
Finding a way to lower emissions
With private O&G companies flaring at almost six times the level of intensity of publicly listed companies, it’s crucial that organizations can find a means of lowering their methane emissions in a cost-effective, commercially viable manner.
Meanwhile, landfill sites and wastewater account for approximately 20% of all methane emissions. According to the EPA, the methane emissions from landfills in 2019 were approximately equivalent to the greenhouse gas emissions from more than 21.6 million passenger vehicles driven for one year—or the CO2 emissions from nearly 12 million homes.
Unburned methane
The release of unburned methane is a contributor to global methane emissions, though it is far less common
It’s also worth noting that venting, the release of unburned methane is another contributor to global methane emissions, though it is far less common than flaring. However, it has been proven to be more harmful to the environment. Flaring one metric ton of methane produces approximately 2.7 metric tons of carbon dioxide.
If that same quantity of methane is vented, on the other hand, then it would have the same global warming potential (GWP) as 86 metric tons of carbon dioxide over a 20-year horizon.
But why is methane so harmful?
The main problem is that methane’s ability to trap heat in the atmosphere, its Global Warming Potential, is 28 - 34 times greater than CO2’s.
Methane emissions from flaring and landfill sites, therefore, pose a significant danger to the planet meaning they must be lowered as soon as possible.
What’s the solution?
A recent UNEP report suggests covering up landfill sites to trap potential methane emissions.
These trapped gases can then be fed back into biogas plants, though there are certain challenges associated with making sure the gas quality is suitable for the generators.
1.2MW gas generators
Aggreko's generators were used to power 40,000 homes throughout the region
But with the appropriate technical know-how, these challenges can indeed be overcome. For instance, Aggreko implemented eight 1.2MW gas generators at two sites in Brazil, Latin America’s largest landfill to provide a total of 10MW of renewable energy.
This was used to power 40,000 homes throughout the region, saving more than 100,000 tonnes of carbon emissions over the contract’s lifecycle and 24,440,400 Nm3 worth of methane emissions annually.
Resource efficiency benefits
When it comes to flaring, innovative solutions have been created that enable companies to capture flare gas. They can then use this to power their operations going forward, or they could potentially export this power back to the grid.
This means that organizations can significantly reduce their methane emissions. They can also benefit from increased resource efficiency, cut fuel costs, and even create a new revenue stream.
Methane index
This process is highly technical and requires specialist expertise. For instance, the gas quality must be just right.
If the H2S levels (i.e. the sulfur content) are too high then this will negatively impact the generators. What’s more, the methane index, the percentage of methane that needs to be removed from the gas before being fed into the generator needs to be just right.
Consistent gas volumes
Because flared gas is typically APG, with oil, the gas volume and pressure can often be inconsistent
And then there’s the issue of having sufficient and consistent gas volumes. Because flared gas is typically ‘associated petroleum gas’ (aka ‘APG’), with the main product being oil, the gas volume and pressure can often be inconsistent.
The pressure may therefore not be sufficient to provide a steady stream to feed into the generators. Or, if it’s too high, then it will become unsafe.
Flaring gas
Finally, organizations face another major challenge when they try to connect their flare gas-generated power to the market (ie. the grid). They need to first build infrastructure from the field and there may not always be an economic case to justify such investments.
This could be one of the reasons why the gas is flared in the first place, the gas producer may believe that volumes, distances, and economics don’t stack up to justify building a pipeline to connect it to the market. However, these problems can indeed be overcome.
Cost-effective, reliable power
This was the case in Kurdistan. A Middle East Operator’s oil production capacity was limited to 30,000 barrels of oil per day (bopd), otherwise, the gas would be depleted too quickly and they would have to flare above the emissions limits. Aggreko implemented a customized solution to instead convert this gas into power.
As a result, the company managed to save 840 tonnes of CO2 emissions per day. Not only this, but Aggreko implemented a 6.5km pipeline and an upgraded 33km power line to stabilize the national grid providing cost-effective, reliable power to the entire region.
Power generation units
The new power generation units that Aggreko introduced helped the company to reduce diesel consumption
Another example is Pharos Energy, a UK-based independent oil company, which worked with Aggreko to reduce gas flaring, and diesel consumption, and provide cooking gas to communities in Egypt’s Western Desert.
The new power generation units that Aggreko introduced helped the company to reduce diesel consumption by 730,000 liters per year, leading to additional emission savings of 2,000 tonnes of CO2 per year. These two projects just go to show that with the right technical expertise, flared gas can indeed successfully and economically be put to good use at scale.
Where Aggreko comes in
Aggreko has significant expertise and years of experience helping companies capture their landfill-emitted or O&G flare gas and put it to good use. Its innovative range of solutions can be rolled out at scale, providing significant environmental and economic benefits.
If all flared gas was turned into power-generating fuel, it could provide approximately 750 billion kWh of electricity. To put this into perspective, that’s more electricity than Africa’s current annual consumption. Aggreko's solutions have powered projects throughout the world, contributing more than 1GW of installed power capacity through flare gas. This is enough to power more than one million homes every hour.
Unlocking methane’s hidden potential
The link between methane emissions and global warming has been well documented. However, with the right technology in place, and by working with specialist experts, organizations can generate reliable and cost-effective power from their otherwise wasted methane emissions.
This allows them to cut costs, open up new revenue streams, and more importantly, reduce emissions. Generating power from landfill and/or flare gas reduces the need to generate equivalent quantities of electricity with fossil fuels like coal or diesel, especially in circumstances wherever renewables are not yet an option.
