Borås Energi & Miljö operates a joint facility consisting of the Sobacken municipal waste handling facility, which produces biogas by the anaerobic digestion of organic waste. The biogas generated here is piped 7 km to the Gässlösa site where the municipal WWTW is located. The biogas generated from the digestion of sewage sludge is combined with that which has been piped from the Sobacken site and upgraded via a chemical absorption process. Some of the upgraded gas is returned to Sobacken for use by the refuse vehicles and the remainder is piped to the nearby biomethane refuelling station.
Ramboll was involved in the installation of a new compressor building, gas storage and gas filling station for buses. The plant is designed to compress 600 Nm3 of biomethane per hour to 250 bar (g). The gas storage contains 10 000 Nm3 of vehicle gas, also compressed to 250 bar(g). There are 43 parking places for buses, each equipped with a gas filling nozzle. The busses are slowly filled with gas for 5 hours during the night. The plant was designed, procured and built by Processkontroll, Sweden.
Aiming to make Borås a fossil fuel free city
This project has taken Borås Energi & Miljö a step closer to realising its aim, which is to make Borås a fossil fuel free city by introducing further infrastructure required to make this a reality. Borås has become a model for other cities as it was the first city in Sweden to invest in a biogas plant. Running the city’s buses on biogas reduces both emissions and noise within the city centre.