Soil and methanization - Final report, June 2023

The development of renewable energies (RE) is one of the most important ways to get away from the use of fossil fuels, a major cause of climate change. The development of these energies also allows the implementation of energy production on the territory while the country suffers from a significant energy dependence on imports: oil, gas and uranium. France is committed to ensuring that 32% of the energy consumed in France and 40% of the electricity produced is of renewable origin by 2030, with the aim of achieving carbon neutrality by 2050. However, renewable energies have environmental impacts, particularly on the soil. Soil is one of the major planetary challenges, a limited resource on a global scale and non-renewable on a human life scale. It is essential for maintaining human activities, food security, achieving carbon neutrality, the health of populations, and the preservation of biodiversity and ecosystems. This study aims to evaluate the surface areas necessary for the development of biogas production by methanization. It proposes surface references to the energy produced, and evaluates the surface areas necessary to achieve t he objective of carbon neutrality in 2050 according to the scenarios proposed by ADEME in Transition(s) 2050 (ADEME, 2021). The analysis identified several issues for soils and their use with regard to the deployment of methanization for energy production in metropolitan France, including: The challenges of cover crops for energy purposes (CIVE) to both promote soil quality and limit competition with other agricultural productions, in light of the assumptions of strong development of this sector in the Transition(s) 2050 scenarios. The need to ensure the implementation of good practices, including the generalization of humic balances to support the design of crop systems to feed methanization plants, the consideration of competition for water resources, and good practices for the management and spreading of digestates. This document is completed by specific documents for other renewable energy sectors (onshore wind, offshore wind, solar photovoltaic, industrial and collective wood energy and biofuels) as well as a summary document entitled 'Soil and renewable energy'. (authors)