Could France achieve a 100 percent transition to domestically produced renewable gas? It could by 2050 according to a new joint study on the technical and economic feasibility of 100 percent renewable gas published by the French Agency for Environment and Energy Management (ADEME), Gaz Réseau Distribution France (GRDF), a wholly owned subsidiary of France-headed energy major Engie and Europe's largest developer, owner and operator of gas grids and GRTgaz, a gas grid owner and operator.
Officially launched January 30 at the Assises européennes de la transition énergétique, Bruno Lechevin, President of ADEME, together with Édouard Sauvage, CEO of GRDF and Thierry Trouvé, CEO of GRTgaz, presented the key findings of the exploratory study entitled “La France indépendante en gaz en 2050: Un mix de gaz 100 % renouvelable en 2050?”
Using different assumptions about how each of the production sectors may develop as its starting point and as part of an ongoing process to improve energy efficiency and gain greater control over energy consumption, the study presents four scenarios, three of which envisage a 100 percent renewable gas mix.
According to the study, the theoretical potential for “injectable renewable gas” in France is estimated to be 460 TWh per annum. This would be sufficient to cover the country’s entire projected gas demand 2050 in all four scenarios studied.
Three technology pathways
Three main production pathways for renewable gas are highlighted in the study: methanisation could account for up to 30 percent of the renewable gas production whereas emerging technologies pyrogasification and power-to-gas (PtG) could account for up to 40 percent and 30 percent respectively.
The technical potentials in the study are based on available feedstock resources which do not compete with food use and raw materials. To ensure that these technical potentials are fully accessible to 2050, the study identifies several legislative, logistical and technical issues that need to be addressed:
- obstacles to agricultural methanisation need to be removed,
- the growing of cover crops – intermediary crops which protect the soil between two saleable crops – needs to become a widespread practice
- more unused agricultural and forestry resources need to be harnessed
- technologies with strong potential but which are not yet commercially mature such as pyrogasification and gasification of algae need development
The study also suggests that a gas demand of between 276 and 361 TWh in 2050 can be satisfied by renewable gas for an overall cost of between EUR 116 and EUR 153 per MWh. This includes the cost of production, storage, use and adaptation of the gas networks. The investment cost needed to adapt the networks is described as “reasonable”.
The mass production of renewable gas will involve more decentralised management of the gas grid network and the use of still significant underground storage of gas. The study also shows that it is possible to collect most of the resources by planning adaptations to the gas networks to enable reverse-flow facilities.
A 100 percent renewable gas mix would avoid direct emissions of about 63 million tonnes of carbon dioxide (CO2) per annum, which at a carbon tax level of EUR 200 per tonne, would incur EUR 12.6 billion annually in carbon tax alone. Furthermore, with a 100 percent renewable gas mix, the country’s trade balance would be improved and its energy independence strengthened.
Interaction of gas and power grids
The study emphasises the complementary nature of the electricity and gas grids and stresses that with a high level of renewable energy production, natural gas and electricity grid systems will interact strongly and jointly evolve.
Power-to-gas (PtG) will be used to ensure that surplus production of renewable electricity is not wasted by providing inter-seasonal storage capacity in the gas network. Renewable gas will also contribute to balancing the electricity system with thermal power plants by using renewable gas to provide energy during peak periods.