Possibilities of Biogas Production from Livestock Waste in Latvia

With the adoption of the Green Deal in the European Union (EU), the role of biodiversity, basic principles of the circular economy, climate change mitigation, forest protection and renewable energy increased. Since 2007, biogas production in Latvia has increased significantly, as it was possible to receive co-funding from the EU Funds for the construction of biogas plants. In 2021, inputs of agricultural origin are used by 40 biogas plants with an average installed capacity of 1 MW. The emergence of biogas plants on livestock farms is facilitated by the development of a circular economy producing waste from the production process – manure and feed waste. Anaerobic fermentation results in digestate – a nutrient-rich plant fertilizer that reduces the application of chemical fertilizers. Rational use of biogas can reduce the need for fossil fuels. Energy production from biogas should be encouraged, as waste is used efficiently, thereby generating energy and reducing the release of greenhouse gases into the atmosphere. In Latvia, livestock production is one of the key industries of the national economy, which produces manure and feed waste. The present research calculated the amounts of cattle, pig and poultry manure and feed waste in Latvia. The research analysed livestock farms by number of cattle, pigs and poultry, the potential amounts of manure and waste produced and theoretical biogas output. Theoretically, 309 farms analysed can produce 93.5 mln. m3 of biogas from agricultural waste and construct 269 new biogas plants. A policy for supporting the construction of new biogas plants would contribute to the country’s independence from fossil energy sources, as well as increase the proportion of renewable energy sources to 50-70 % in final energy consumption by 2030. Farmers on whose farms a biogas plant could be built need to carefully consider the uses of the biogas produced. The uses could be thermal energy generation for heat supply, cogeneration (thermal and electrical energy) or biomethane production.