DON'T get your hopes up for electrically-powered vessels to replace fuel oil guzzling mega ships that carry the world's trade today, says New York's IEEE Spectrum, the official journal of the Institute of Electrical and Electronics Engineers.
What exists in that line today is the Yara Birkeland in Norway, the world's first electric-powered, zero-emissions containership, as well as the first autonomous commercial vessel.
Before thinking this is the future, consider that the best the Yara Birkeland can do is carry 120 TEU at six knots for 30 nautical miles?between Heroya and Larvik in Norway with batteries that can deliver seven to nine megawatt hours, says the IEEE Spectrum article.
To do what a conventional containership does routinely that is carry 18,000 TEU from Hong Kong to Hamburg at a fuel-saving 16 knots 31 days, the electric ships would use 40 per cent their cargo space to house the batteries, 'an economically ruinous proposition, never mind the difficulties involved in charging and operating the ship,' said article.
'And even if we push batteries to an energy density of 500 Wh/kg sooner than might be expected, an 18,000-TEU vessel would still need nearly 60,000 tonnes of them for a long intercontinental voyage at a relatively slow speed.
'The conclusion is obvious. To have an electric ship whose batteries and motors weighed no more than the fuel (about 5,000 tonnes) and the diesel engine (about 2,000 tonnes) in today's large container vessels, we would need batteries with an energy density more than 10 times as high as today's best lithium-ion units,' it said.
'Load the ship with today's best commercial Li-ion batteries (300 Wh/kg) and still it would have to carry about 100,000 tonnes of them to go non-stop from Asia to Europe in 31 days,' it said.
WORLD SHIPPING
What exists in that line today is the Yara Birkeland in Norway, the world's first electric-powered, zero-emissions containership, as well as the first autonomous commercial vessel.
Before thinking this is the future, consider that the best the Yara Birkeland can do is carry 120 TEU at six knots for 30 nautical miles?between Heroya and Larvik in Norway with batteries that can deliver seven to nine megawatt hours, says the IEEE Spectrum article.
To do what a conventional containership does routinely that is carry 18,000 TEU from Hong Kong to Hamburg at a fuel-saving 16 knots 31 days, the electric ships would use 40 per cent their cargo space to house the batteries, 'an economically ruinous proposition, never mind the difficulties involved in charging and operating the ship,' said article.
'And even if we push batteries to an energy density of 500 Wh/kg sooner than might be expected, an 18,000-TEU vessel would still need nearly 60,000 tonnes of them for a long intercontinental voyage at a relatively slow speed.
'The conclusion is obvious. To have an electric ship whose batteries and motors weighed no more than the fuel (about 5,000 tonnes) and the diesel engine (about 2,000 tonnes) in today's large container vessels, we would need batteries with an energy density more than 10 times as high as today's best lithium-ion units,' it said.
'Load the ship with today's best commercial Li-ion batteries (300 Wh/kg) and still it would have to carry about 100,000 tonnes of them to go non-stop from Asia to Europe in 31 days,' it said.
WORLD SHIPPING