March 2013 saw Rolls Royce collect the Green Ship Technology Award at the Green Ship Technology Conference in Hamburg for its Environship concept, which has lean burn Bergen Engines gas power units at it core. The Environship combines a range of Rolls Royce technologies (Bergen Engines is a subsidiary business) in a cargo ship model that, set against comparable vessels using diesel power engines, offers CO2 reductions of up to 40% (alongside 92% reductions in NOx and 100% less SOx emissions).