CO2-neutral dairy farming thanks to circular biogas production

Most sustainable village

The Noord-Deurningen Energy Neutral Foundation won a competition in 2010 with the plan to make Noord-Deurningen the most sustainable village in Overijssel. Dairy farmer Martin Veldscholten formed part of that foundation’s board. The top prize was a working budget, which they used to conduct research into the best options for renewable energy. One of the options was biogas and that was certainly quite appealing to Martin as a livestock farmer and entrepreneur. “Extracting gas from cow manure offered opportunities for sustainability and an additional source of income for dairy farms. But there was still a great deal of unawareness about fermentation, which meant a great deal of pioneering work needed to be done.”

Smooth permit process

Martin found six fellow dairy farmers who were willing to go on this adventure with him. Together they applied for and received a subsidy for the investments from the province of Overijssel. Making sure they had the right permits in place on time was the next challenge. For this they enlisted the help of business development specialist Han Gelevert from FarmConsult. “Han provided us with fantastic assistance”, Martin says. “The municipality hadn’t yet acquired any experience with fermentation. Han subsequently entered into discussions with the officials, alderman and province and organised a neighbourhood meeting one evening to explain the plan in detail.” This open and honest communication during the preliminary phase meant there wasn’t a single objection during the eventual permit procedure.

Local customers

A fermenter is now continuously running at all six dairy farms. Together they produce the equivalent of 1 million cubic metres of natural gas every year; roughly what’s consumed by 900 households. The gas then goes to two local customers: a grower and a producer of additives. “There are only very limited storage options for biogas, which means it needs to be used immediately”, Martin explains. “The grower didn’t need to use any natural gas, with the exception of three days, throughout the last winter, a fantastic result. He has now invested in a large boiler for storing the heat. That’s the next step in the efficient use of biogas.”

Environmental gain

However, the fermenter will result in even more benefits. This includes the fact that the digestate which remains after fermentation is an ideal fertiliser. “We are now fertilising our crops with the digestate for the third consecutive year. This fertiliser is qualitatively better than slurry and the nitrogen utilisation is much higher. This means we hardly need any artificial fertiliser. The crop yield and the quality of the roughage has actually increased. The contractor has calculated that my crop yield is 20% higher than with other farmers and that the protein quality is far above average. An instant benefit for my cows’ rations. And as the fresh manure goes directly into the fermenter, our ammonia and methane emissions in the stable have decreased enormously. So another environmental gain. I now produce completely CO₂-neutral”, the entrepreneur proudly states.