MT-Energie built the projects and has also opened the largest biogas upgrading plant with gas injection into the German grid.
A group of farmers from the Champagne region, south of Paris, are behind the eight projects who decided to become energy entrepreneurs in 2013.
The projects feature a triple-tank facility that is designed to treat 250 Nm3 of gas, which is equivalent to an electrical capacity of about 500kW.
MT-Energie said the first plant overcame its mechanical and biological commissioning in less than one month.
All of the eight projects are scheduled to inject more than 10.5 M Nm3 per year of bio-methane into the French grid by the end of 2016.
MT-Energie bio-methane expert Timo Vaske said: "Opting for biogas upgrading to bio-methane can be a profitable alternative to traditional CHP concepts, producing only electricity.
"Some countries, such as Germany, France, the UK, Italy, are recognising the contribution of AD to gas self-sufficiency, by issuing favourable incentives.
"In some cases, for example in the eight French projects, the electrical grid connection was also not suitable for the power produced, while the connection to the gas grid was carried out without problems."
MT-Energie said the largest biogas plant with gas injection is also leading the way for German sugar producer SuedZucker.
The plant features four solid feeders, two secondary digesters, five residue storage tanks and a gas treatment facility with a capacity of 1,400 Nm3 per hour.
A total of about 12.2 million m3 of biogas per year will be produced in the new biogas plant, which will generate enough electricity for about 6,000 households and 2,000 households with heat.
