A TSO proactive approach to cut down methane emissions

If Natural Gas is considered to be the fossil fuel with the lowest specific carbon dioxide emissions (CO2) for the same quantity of power generated1, methane (the main component of the Naturel Gas) has a far more important effect on global warming than CO2 (GWP100 of 28). 

Therefore, to support the major role Natural Gas has to play in the Energy Transition, the natural gas industry has to proactively deal with methane emissions in the atmosphere all along the gas chain, from gas production to the final customer. 

As a gas transporter, GRTgaz is concerned by this issue. GRTgaz is the main gas TSO (Transmission System Operator) in France, managing 32 456 pipeline kilometres from 16 bar to 95 bar, 9943 stations (delivery, regulating and sectioning) and 28 compressor stations (616 MW in total). 

Methane emission mitigation is not new for GRTgaz which has always been concerned by its environmental impact. The best available technologies have always been followed up at GRTgaz, and have been implemented when they are proved compatible. For instance, High speed integrated compressors have been installed in GRTgaz compressor stations and GRTgaz regularly uses mobile gas compressors to transfer large quantities of gas from pipeline to pipeline, instead of venting them before maintenance works or repairs. As a consequence, the amount of saved gas is continuously increasing. 

In 2016, GRTgaz was certified ISO 50 001 (Energy Efficiency) including its gas emissions reduction program in the certification perimeter and then decided to aim for an ambitious goal regarding gas emissions which are to be divided by 3 by 2020. 

In this paper, the authors will provide the GRTgaz strategy to reduce its methane- emission-related greenhouse gas impact. 

In the first part of the paper, an overview of the GRTgaz emissions data is provided. 
In the second part, the methodologies of evaluation which have been tested and, when relevant, implemented, are given, explaining the final choices. Some decisions have caused internal debates which are decrypted in this paper. In particular, the communication around fugitive leaks has been a cultural revolution. 
In the third part, current actions are described. 
In the last part, current studies and experiences using new methodologies and technologies - which might be implemented in the next few years - are presented.