Carbon Positive: A new energy-efficient container ship design promises a 35 per cent reduction in CO2 emissions, its creator, Mitsubishi Heavy Industries (MHI), claims. The Japanese manufacturer says the key features in the new design are a dual propulsion system and a proprietary air lubrication system for the hull that reduces friction as the vessel moves through the water. An electronically-controlled diesel engine and waste-heat recovery unit also add greater fuel efficiency, while a scrubbing …