CS - Economic Analysis Of Anaerobic Digestion (AD) - A Case Study Of Green Power Biogas Plant In The Netherlands

One of the key concerns of biogas plants is the disposal of comparatively large amounts of digestates in an economically and environmentally sustainable manner. This paper analyses the economic performance of anaerobic digestion of a given biogas plant. A scenario analysis is carried out based on a linear programming model to identify feedstocks that optimize electricity production and to determine the optimal application of digestate. The economic analysis is also based on NPV and IRR concepts, to assess the cost-effectiveness of the biogas system. In addition to a default scenario, management and policy scenarios were investigated. Our findings show that treating RO as green fertilizer as opposed to manure (default scenario) is not only lucrative for the plant but also lessens the environmental burden of long distance transportation of concentrates. This paper also concludes that given the uncertainty of regulations concerning RO and the currently low values of digestate and heat, high investment and operating costs limit the feasibility of anaerobic digestion of wastes of farm origin and other co-substrates unless subsidies are provided.

Key words: Anaerobic digestion, biogas plant, methane yield, reverse osmosis (RO), linear programming (LP) model