Biogas plant manufacturer Weltec Biopower has teamed up with Domaix Energy in Alsace, in the northeast of France to start rolling out four agricultural biogas plant projects in France. Apart from agricultural substrates, the biogas plants, whose construction has already started, will use sludge and food leftovers. This is in line with a trend in French biogas plants to ferment industrial leftovers.
Since the introduction of the separation and utilization of kitchen waste from large catering establishments in France at the end of 2011, organic waste from schools and company cafeterias must be used for the production of energy.
To comply with this policy, Weltec will integrate hygienization units in order to make use of the substances of category 3 according to the EU directive. Another common feature concerns the use of the heat. In all four biogas plants, the residual heat will be used in a digestate dryer in order to reduce the amount of liquid manure and market the dried digestate.
The heat utilization concept boosts the efficiency at the four biogas plants by at least 70 percent, enabling the operators to benefit from the heat and power bonus, which is up to EUR 0.04/kWh in France.
One of the reasons why the four French investors opted for Weltec is that the plant engineering company from Lower Saxony, Germany, is renowned for its individualized implementation. Thus, the two 600-kW plants that are currently being built use similar substrates but differ in terms of the composition and concepts. For this reason, the plant in Charente, southwestern France, makes use of a 3,000-m³ stainless-steel digester, while the other 600-kW plant in Burgundy, central France, will have two digesters with a capacity of 2,000 m³ each.
The two other plants will have an electrical output of 190 kW and 255 kW, respectively. The smaller Weltec biogas plant in Lorraine, also in the northeast of France, comprises a 1,500-m³ stainless-steel digester and will be loaded with cattle manure from the operator’s farm as well as whole plant silage and food leftovers. Additionally, the 255-kW plant will use agro-industrial waste.
Two of the biogas plants currently being built are funded by the farmers. Domaix Energie from Gundershoffen, Alsace, and Methanor, a French biogas fund, are involved in the financing of the other two plants.