Averting methane emissions in the fossil fuel industry.
Methane and flaring is a climate issue. The scope of it is dramatic: Put simply, the methane emissions from the fossil industry would alone warm earth by .3 °C from now to 2045 if not addressed. Methane emissions are way more potent to global warming than carbon dioxide, especially in a short period of time. The anthropogenic methane emissions are mostly due to agriculture (41.7%; IEA, 2021) and fossil fuels are in a close second (34.2%; ibid.). Here, leaks emit natural gas, associated gas of oil and coal production is not used and not cared about or the operator does not want to invest in a burner to flare.
In 2020, the fossil fuel industry emitted 135 million tons (Mt) of methane, with an additional 139 billion cubic meters (bcm) of natural gas flared in 2022. The amount of gas flared is greater than the combined consumption of Germany and Turkey, and is equivalent to 1,450 terawatt-hours (TWh) and 500 million tons (Mt) of CO2 emissions. This is slightly less than Canada's emissions and slightly more than Brazil's emissions that year. And all the gas and energy went to waste while extra fuel was burned to create heat.
Why does methane leak and flaring occur?
When drilling for oil, natural gas often comes up as a byproduct. This is because natural gas pockets are often located in the same reservoirs as petroleum. This gas is sometimes re-injected into the oil field, but too often it is simply vented or flared. “Of an estimated 935 bcm of gas that was extracted in association with oil in 2019, we find that only around 75% ended up being used on-site by the operator, or re-injected into the well, or marketed to consumers. Of the remaining 25%, we estimate that around 55 bcm was released as methane to the atmosphere, and the remaining 150bcm flared.” (IEA, 2019)
Use of associated gas, Data Source IEA, 2019.
Flaring often occurs for economic reasons. Oil fields are usually far from other infrastructure, leading to higher costs for processing of associated gas than for the amount produced in natural gas fields. Additionally, producers would rather avoid the expense of re-injection. From a technical standpoint, the processing or re-injection of associated gas can be impossible if natural gas is a byproduct in a large, dispersed oil field with many mini-leaks.
Sometimes regulations limit the production of natural gas, especially when oil extraction rights are restricted. In addition, fines for flaring may not be high enough to justify the cost of building the infrastructure needed to process, use, re-inject, or sell the gas.
And then there is the small but vital case of safety: “Flaring may be required for safety reasons. Extracting and processing oil and gas involves dealing with exceptionally high, and changeable, pressures. [...] Gas flaring allows operators to de-pressurize their equipment and manage unpredictable and large pressure variations by burning any excess gas.” (World Bank , 2022) The Net-Zero plan aims to lower flaring by limiting it to safety flaring, which will prevent 95% of the gas from being flared. However, optimizing safety flaring is still necessary.
Solutions for associated gas
Leaks in equipment can be repaired and sealed like it appears to be the solution for this example from a couple days ago. On sites with associated gas that have no infrastructure to deal with gas however need feasible solutions.
- On large sites, the gas can be used to generate power with traditional power equipment.
- Fueling onsite engines or boilers
- Gas-to-liquids (GTL) can work modular and on a small scale to produce syngas of methanol
- Small-scale LNG solutions
While flaring is questionable for non-safety reasons due to emissions, it is a simpler solution than the above. And burning natural gas is better than letting it escape as methane into the atmosphere. However, after flaring or burning, the energy should be used rather than wasted to avoid additional fuel. Typically, associated gas, and therefore flaring, is neither constant nor regular. This means it is better utilized with a high-temperature storage.
This allows the heat to be shifted to match the energy supply for the onsite steam or heat generation. Kraftblock's modularity and flexible scale allows it to handle different amounts of flaring at different locations. And if the energy needs to be moved, Kraftblock's system can also be mobile. Since we test flare gases in the steel industry at 1,100C to 1,300C, most of the energy of the flared gas in the oil and gas industry can be stored in the storage.
Summary
It is critical for humanity to stop methane leaks and venting. This can be achieved through various solutions if oil and gas is not yet phased out, such as repair, better sealed equipment, power generation, or commercialization with gas-to-liquids plants.
We need to reduce flaring as much as possible. If there are flares, we have to use the energy. The heat has a high value and can be used in processes, for steam generation or other heating purposes on or off site with heat storage.
Additional statistics: Who flares gas?
This World Bank chart shows the trend and amount of flaring by the top 10 flaring countries. Russia, Iraq, and Iran are burning the most gas into the atmosphere, followed by Algeria, Venezuela, and the United States with somewhat smaller amounts. While Nigeria is reducing the amount of gas it flares, there seems to be a trend for Mexico, Libya and China to increase flaring.
Source: World Bank, 2022
Regarding leaks and venting, in addition to the chart of the Use of associated gas, you can read about methane super-emitting events, especially from Turkmenistan, India, the U.S. and Russia in this piece by The Guardian.