The projects include conversion of the Biowatt biogas plant in Brittany into a biomethane upgrading facility and construction of the new Valoverte biomethane plant in south-west France.
Biowatt conversion
The Biowatt facility, originally commissioned in 2010, represents EnviTec's first French biogas project. Operating initially on pig slurry, agricultural waste and fats at 526 kW electrical capacity, the plant has evolved through iterative expansion to 889 kW following integration of additional agricultural and agri-food residues, pasteurisation infrastructure and expanded digestate storage.
A 2025 partnership agreement initiated conversion to biomethane production. EnviTec will install an EnviThan gas upgrading unit with 250 normal cubic metres per hour biomethane capacity, manufactured at EnviTec's Saerbeck site, with delivery and commissioning scheduled for end-2026.
Concurrent works include mixer replacement, conversion of existing storage into additional digester capacity, digester roof renewal and biogas boiler integration.
The biomethane will be injected into the grid of French operator NaTran via a dedicated 13-kilometre shared pipeline to Loudéac for local heat supply in the tertiary sector. Digestate remains in regional agricultural circulation as biofertiliser.
Valoverte project
The second project, commissioned by recycling company Cler Verts, represents EnviTec's second facility for this operator. The first, Cler ENR (commissioned 2015, 637 kW), has informed the new Valoverte design. The new plant features an EnviThan unit with 280 Nm³/h biomethane capacity targeting approximately 25 GWh annual biomethane production.
Feedstocks comprise agricultural residues and food industry by-products. Depackaging and hygienisation occur at a separate facility before substrate introduction. Earthworks are underway, with tank installation scheduled for September 2026, followed by piping, assembly and EnviThan delivery. Injection into the GRDF network is scheduled from July 2027 onwards for local heat generation.
Market context
EnviTec has realised 48 plant projects in France since 2007. France's February 2026 multi-year energy plan reaffirmed ambitions for 62 TWh biomethane production by 2035. Current support relies on regulated feed-in tariffs, with transition toward biogas production certificates (CPB). The final CPB mechanism design is expected within months.
Christian Ernst, EnviTec's Southern Europe Sales Manager, characterised France as a strategic growth market and one of Europe's most dynamic biogas sectors.
