The Gaec Bon Vent has launched the first methanization unit of its kind located in the agglomeration of La Roche-sur-Yon, in Chaillé-sous-les-Ormeaux. The farm produces four times more energy than it consumes.
"Strive for autonomy, respecting the environment and exploiting all the resources of the farm". This is the credo of Gaec Bon Vent, created just thirty years ago, in Chaillé-sous-les-Ormeaux.
This exploitation
atypical, led by six members of the same family, is based around a breeding of 200 suckler cows and 150 sows, on 450 ha half dedicated to crops and grass areas for the rest.
The ecological fiber is passed down from generation to generation, and on all the "floors" of the farm. In 2004, the family clan had already innovated, creating a food factory on site, which covers 85% of livestock needs.
Installed from 2009, 1,500 m² of solar panels today provide more than 200,000 kilowatt-hours per year, almost all of which are sold out. A new course was reached in February, with the creation of an anaerobic digestion unit. The first of its kind located in the agglomeration of yonne.
A "virtuous circle"
An investment of 2.4 million euros, launched after careful consideration. "In 2006, we had already thought about it. But profitability was not at the rendezvous. Since then, the purchase price of electricity from anaerobic digestion has been simplified and enhanced, " says Xavier Grelier.
A new deal, which prompted the Gaec to take the plunge. "Anaerobic digestion is a virtuous circle that transforms waste into deposits. Today, all of our effluents are used in this unit " . These 3,000 tons of manure and 4,000 tons of manure constitute 65% of the "deposit" , the organic matter needed to produce biogas.
Energy crops (oats, straw), dedicated crops (corn silage) and products purchased from a trading company provide the remaining 35%.
"The unit includes two large 1,000 and 3,000 m3 tanks, the digester and the post-digester, and a 350-kilowatt motor. The production of biogas is enhanced by a process of cogeneration, " says Xavier Grelier.
The equivalent of 550 homes
Nine months after the launch, the balance sheet is more than positive. The unit produces 2,800 megawatt hours, the equivalent of the average consumption of 550 homes.
All of this electricity is sold to EDF, which has contracted to take it back, for a price of 20 cents per kilowatt hour, over a period of 15 to 20 years.
Part of the heat produced is used to heat the building dedicated to piglets. The digestate, a black liquid resulting from the "digestion" of the machine, is used to fertilize the soil, making it possible to complete the loop. "In the end, thanks to anaerobic digestion, we produce four times more energy than we consume," says Xavier Grelier.
Green and renewable energy, which reduces both the carbon footprint of 400 tonnes of CO2 per year, the smells associated with land application and the use of inputs.
A showcase for the company and a source of satisfaction for the six partners. "Farmers are often labeled polluters. Today, we prove that profitability and ecology can go hand in hand . "