Ireland-based B9 Shipping has started work on a full-scale demonstration vessel as part of its goal to design the modern world’s first 100 percent fossil fuel-free cargo sailing ships. Unlike most conventional large cargo vessels, which are powered by bunker fuel, B9 Shipping’s cargo ship would employ a Dyna-rig sail propulsion system combined with an off-the-shelf Rolls-Royce engine powered by liquid biomethane derived from municipal waste.