The share of renewables in energy consumption has grown sharply over the past 10 years, but the inmittence of solar and wind production systems is a problem. In this context, the HYCAUNAIS project proposes to develop an energy storage solution to alternate between periods of production and consumption. Power-to-Gas (P2G) is based on a water electrolysis process that generates green hydrogen, which, combined with carbon dioxide, produces synthetic methane similar to natural gas and compatible with transmission, distribution and consumption facilities. The project brings together a consortium of 5 private partners including 1 SME (STORENGY, AREVA H2Gen, ENGIE GREEN, Electrochaea, ENGIE Lab Crigen) and three regional public partners (SDEY, SEM Yonne Energie, and Université de Franche-Comté). It presents three economic ambitions: —Demonstrate the feasibility of operating a flexible P2G system adapted to its territorial context. Improve biological methanation technology. —Reply the technological and commercial model developed. Thus, the project promotes the development of NRTs in CFB by providing a territorial and national solution to intermittency management. The success of the project will lead to a replication of P2G units, with a turnover over the period 2024-2034 which could amount to approximately EUR 300 million and 25 to 45 associated jobs for Storengy.