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The world's first hybrid self-charging cargo ship has paid a visit to Plymouth.
The Aasfjell, a 394-foot Norwegian vessel, is equipped with a battery which will help it reduce fuel consumption by around 400 tons per year.
Sea freight is already one of the most sustainable ways of transporting goods - but Plymouth's harbourmaster Richard Allan says there is still more to do.
"Three per cent of the world's greenhouse gases comes from the maritime and shipping industry, which is quite small relatively, considering 95 per cent of the world's trade moves by the sea," he said.
"But we must do better.
"Our aim is to maintain the good condition of what we've got in Plymouth Sound, and improve the less favourable conditions."
Steve Marshall, general manager at Victoria Wharf, says everybody in the city's port is doing their bit to cut emissions.
"The investment isn't cheap, and the fossil fuels are readily available, but we do have a responsibility to look after the planet and to work towards net zero by 2050."