Finnish shipping company Wasaline announced it has started operating with certified biogas one day a week from October 13, in preparation for the EU emissions trading system that will come into force next year.The company, which operates the route connecting Vaasa, Finland and Umeå, Sweden, said it will use certified biogas aboard its ro-pax vessel Aurora Botnia for all Friday departures through December 22 as part of its “Green Fridays” pilot project.Biogas is more expensive than liquefied natural gas (LNG)…