National Contact Point for Renewable Energy Sources

Agricultural Biogas Systems

Biogas systems are installations that produce energy from biogas obtained primarily through the fermentation of plant biomass, animal manure, organic waste (e.g., from the food industry), municipal waste, slaughterhouse waste, or biological sludge from wastewater.

Energy obtained from biogas is classified as originating from renewable energy sources within the meaning of the RES Act. The detailed course of the biogas production process depends on the type of biogas system. In most cases, the biogas produced is used to generate electricity and heat in cogeneration. Other biogas systems process and purify biogas into biomethane and inject it into the gas network or subject it to liquefaction or compression processes, transporting the gaseous fuel by means other than gas networks. As a by-product of biogas system operations, digestate (fermentation residue) is obtained, commonly referred to as digestate. Its use depends on the composition of the biomass used for biogas production, but digestate is most often used in agriculture:

a) As a fertilizer or a plant growth aid, based on the provisions of the Act on Fertilizers and Fertilization, after meeting the requirements for obtaining a permit for placing on the market (pursuant to Article 4 of the said Act);

b) As part of waste processing in recovery procedure R10, under the provisions of the Waste Act, after obtaining a permit for waste processing in procedure R10, as referred to in Article 42(2) of the said Act.

The operation of biogas systems is particularly linked to agricultural activities, primarily due to access to raw materials. Unlike most types of RES installations, the operation of biogas systems does not depend on weather conditions but on a constant supply of biomass. It is assumed that agricultural biogas systems can produce energy for up to 8,000 hours per year (90% of the time), compared to other RES installations, whose annual availability ranges from 10% to 40%.

For this reason, biogas systems constitute a valuable component of the renewable energy system, which still has significant development potential. Current estimates indicate the possibility of obtaining up to approximately 8 billion m³ of agricultural biogas annually in Poland.

An agricultural biogas system is a RES installation used to produce agricultural biogas within the meaning of Article 2(2) of the RES Act, i.e., gas obtained through methane fermentation of:

a) Agricultural products and agricultural by-products, including animal manure;

b) Products from the processing of agricultural-origin products and by-products, waste, or residues from such processing, including food processing and production, originating from industrial plants, as well as from industrial wastewater treatment plants in the agri-food sector, where industrial wastewater is separated from other types of sludge and wastewater;

c) Expired or unfit-for-consumption food products;

d) Fats and oil-water separation mixtures containing only edible oils and fats;

e) Plant biomass collected from areas other than those registered as agricultural land;

f) Animal manure obtained from non-agricultural activities;

- excluding biogas obtained from municipal waste, landfills, and substrates originating from wastewater treatment plants other than those listed in point b.

Agricultural biogas systems are the most common type of biogas systems in Poland. The investment process for agricultural biogas systems may differ from standard procedures due to the need to accelerate the implementation of investments using this technology.