The economic potential for production of upgraded biogas used as vehicle fuel in Sweden

Abstract

In various literatures, the technical potential of biogas in Sweden has been investigated, but less effort has been spent on investigating the economic potential. This study investigates the economic potential for upgraded biogas produced by anaerobic digestion with the purpose of using it as vehicle fuel. Costs that have been considered covers the investment cost for a large scale, central biogas plant, price or compensation for feedstocks used, transportation costs for the feedstocks and costs associated with hygienisation. Feedstocks included in the study are wastes from agriculture, food wastes from households, restaurants and shops, wastes from industry, sludge from sewage treatment works and energy crops. The result is divided into two scenarios; the first includes all current wastes and residues from society, while the second also includes energy crops grown on 10 percent of the Swedish arable land. The curves show that biosludge from paper and pulp industry and slaughterhouse sludge results in a negative production cost, thanks to the compensation for waste handling received by the biogas plant. Biogas produced from whey and waste milk and energy crops is the most expensive. If prices of petrol and biogas are assumed to remain constant at current levels, then upgraded biogas would have to be produced at a maximum cost of about 0.37 SEK/kWh in the best case. With such a constraint, the resulting biogas potential would correspond to a yearly production of 5.2 TWh. Since it reflects the best case scenario, the real biogas potential is probably lower, unless governmental financial support is given or regulations favouring biogas production are implemented.