Nothing quite spoils a cruise on the ocean like the noise of diesel engines down below. It’s not just about the racket though – the marine industry is conscious of environmental issues such as emissions, and is looking at ways it can change through new technology.

A report by research group IDTechEx says every container ship emits the same amount of CO2 as 75,000 cars. But it’s not just commercial vessels – the luxury yachting industry is also having to transform itself.

Some builders are developing hybrid setups that use a combination of a petrol or diesel engine and an electric motor. They provide distance as well as the ability to cruise silently in the harbour in electric mode. Electric also means you can switch off the polluting side of the engine when you are in an environmentally sensitive area such as a coral reef...