Manure fermentation is a development within the agricultural and other sectors which offers a great deal of potential and addresses the desire for the availability of locally produced, renewable energy sources as a replacement for fossil fuels. Manure fermentation results in a reduction of greenhouse gas emissions, as shown in a study by Wageningen UR (University & Research centre), commissioned by the province of Gelderland and the Eastern Office of the Directorate of Regional Affairs of the former Dutch Ministry of Agriculture, Nature and Food Quality.
It must be remembered that fermentation is not a perfect integrated solution to the range of problems which includes manure surpluses, the need for green energy, the need to limit ammonia emissions, and odour nuisance. However, it does help improve the situation. Given current technology and sales channels, fermentation is not yet financially profitable and therefore it requires subsidising. Manure fermenters often also face social objections. They may be helping the environment, but no one wants them in their back yard. Follow-up research would do well to closely examine the experiences in this regard in Germany.
Small-scale fermenters
Agriculture in the province of Gelderland has an important role in the production of raw materials for food and animal feed. Two major challenges for the sector are the transition to more sustainable agriculture and the transition to a biobased economy. In the opinion of the province of Gelderland and the Eastern Office of the Directorate of Regional Affairs, there is potential for agriculture to contribute to sustainable energy production.
Research indicates that there is more manure than biomass available in Gelderland. The amount of biomass in Gelderland is limited by massive increases to the scale of animal manure fermentation in combination with co-substrates, in proportions dictated by current legislation (50% manure/50% co-substrate). Small-scale fermenters which only use animal manure are a new development. There are a number of advantages to this: maximum avoidance of greenhouse gas emissions, the fact that input from substrates is unnecessary, and minimum disturbance to the manure market and manure production. It is also minimally labour-intensive. The energy produced can largely be used on the farm where it is produced. Wageningen UR’s Sterksel pig innovation centre has just such a small-scale fermenter.
Download
Report 505, Opportunities and threats for manure fermentation and green gas production in the Gelderland agriculture: a primary investigation, by G. Migchels et al. can be downloaded here for free.