Methane emission affects advocacy of natural gas as a low-carbon fuel because it has a global warming potential 25 times greater than CO2. Managing methane emissions across the gas value chain is critical for an oil and gas company for natural gas to be qualified as a cleaner fuel in the energy transition. Methane emission usually is quantified from key intended emission sources such as venting, flaring, and combustion. This monitoring of the greenhouse-gas emissions enables gradual reduction of large intended methane sources. Unintended fugitive methane emission, however, as well as those from other small intended sources such as compressor seals, are usually not quantified and reported.
To support the energy transition, a need exists to increase accurate quantification and reduction of methane emissions and determine long-term reduction targets to drive the competitiveness of natural gas as a low-carbon fuel. To this end, an initiative was taken to measure baseline data for methane emission for gas-processing facilities and gas-transmission and regasification unit by using accurate measurement tools and methods for detection and quantification.
A methane-quantification tool was developed in-house by Petronas Group Technical Solutions Process Simulation, with the two Petronas business units as users. Methane emission is quantified on the basis of applicable methane sources listed in guidelines produced by the Oil and Gas Climate Initiative. The quantification covers the following methane emission sources based on the applicability to the sample plants:
- Unintended release
- Fugitive leaks
- Loss of primary containment
- Intended release
- Venting of hydrocarbon
- Flaring of hydrocarbon
- Stationary combustion
- Compressor seals
- Pneumatic controls and pumps
The volume of methane emission from fugitive leaks, compressor seals, and pneumatic devices had not been quantified accurately in Petronas until the methane quantification tool by was established.