[V.Narayan]

e-CARGO LINERS

Ships lend themselves to battery, wind and solar powered solutions better than cars for three reasons. First there is a lot of wind while at sea and often, depending on the latitude a lot of sun. Second a ship by laws of physics requires much less energy to haul a given weight at a given speed especially if that speed required is a low speed. Roughly speaking a ship weighing 30,000 tonnes cruising at 9 knots requires only ~2800 shp for propulsion. The exact figure would vary by ship design but this is a directionally correct figure. Third a ship can carry a larger proportion of its total weight (called displacement, remember Uncle Archimedes) as battery weight than a car. The need to move to renewable energy sources is great amongst the shipping industry given that all ships together across the world cause more pollution than all the cars together.

The shipping industry is under pressure to reduce emissions of CO2 and other greenhouse gases. Shipping accounted for 2.9% of global manmade greenhouse gas emissions in 2018, according to the International Maritime Organization (IMO), the UN body that regulates global shipping. In the same year, the IMO introduced a mandatory 50% reduction of total annual greenhouse gas emissions by 2050 — with the ambition to reach zero emissions "as soon as possible in this century."

Given this background we are beginning to see two prototypes being built/designed for commissioning in the short term. Not surprisingly these are by two of the most technologically advanced engineering nations – Sweden and Japan. We examine these two below.

Modern Sailing ship

Oceanbird might look like a ship of the future, but it harks back to ancient maritime history -- because it's powered by the wind.
The transatlantic car carrier is being designed by Wallenius Marine, a Swedish shipbuilder, with support from the Swedish government and several research institutions.

With capacity for 7,000 vehicles, the 650 foot-long vessel is a similar size to conventional car carriers, but it will look radically different. The ship's hull is topped by five telescopic "wing sails," each 260 feet tall. Capable of rotating 360 degrees without touching each other, the sails can be retracted to 195 feet in order to clear bridges or withstand rough weather. The sails, which will be made of steel and composite materials, need to be this size to generate enough propulsive power for the 35,000-ton ship.

Large, conventional Roll On Roll Off car carriers use an average of 40 tons of fuel per day, generating 120 tons of CO2 -- equivalent to driving a car 270,000 miles.



All Electric ship prototype

Similarly a Japanese consortium is designing a prototype of an all electric oil carrier ship powered by a 3500 Kwh battery. This ship, smaller than a typical cargo liner, would be 62-metres in length and have a payload of 1300 cubic metres of oil. This would serve as a proof of concept prototype before Japan embarks on full sized oil tankers



There are several other hybrid and experimental projects underway or already on test but the two above are the most dramatic of the lot so far. Watch this space. Significant changes are afoot. In a decade the first true cargo liners powered by renewable energy are likely to be sailing on commercial routes if these prototypes succeed. The changes that are afoot are as exciting and fundamental as the change that took us from wind powered to coal fired steam ships. We live in exciting times to be witnessing these changes unfold.

I shall be updating this thread as the months and years go by. Right now threads on electric modes of transport - aircrafts and ships and green topics like renewable energy or climate change do not attract attention by our readers. I suspect that will change significantly over the decade ahead.

[Aditya]

Thread moved out from the Assembly Line. Thanks for sharing!

[landcruiser123]

Thanks for sharing V.Narayan. I'm not confident about battery powered ships being commercially viable due to the law of diminishing returns. In general, BEVs will only be a small blip in the technological evolution we're going to see in the coming decades.

Hydrogen is the future of fuel for trucks, rail, and ships. https://www.lifepr.de/pressemitteilu...0/boxid/835448

Originally Posted by V.Narayan

Right now threads on electric modes of transport - cars and ships and green topics like renewable energy or climate change do not attract attention by our readers.

I think the projects showcased in the EV sub-forum are amazing. I'm actually more excited about the affordable EVs offerings in the pipeline for India compared super advanced gadgets Tesla makes. I have no doubt that Chinese, Koreans, and Tata/Mahindra will have some amazing vehicles ready.

Example:https://www.team-bhp.com/news/conver...e-electric-car

[V.Narayan]

Originally Posted by landcruiser123

Thanks for sharing V.Narayan. I'm not confident about battery powered ships being commercially viable due to the law of diminishing returns. In general, BEVs will only be a small blip in the technological evolution we're going to see in the coming decades.

Hydrogen is the future of fuel for trucks, rail, and ships. https://www.lifepr.de/pressemitteilu...0/boxid/835448

Dear @landcruiser123, thank you for reading and sharing your link to hydrogen as a fuel. Certainly hydrogen is very promising where transportation of cars, ships and aircrafts go. Right now a lot of options are up in the air and only time will tell which works out to be the optimum balance between economics, green and convenience. I wonder, and I don't know, what will be the impact of vast amounts of water vapour being pushed into the atmosphere - more rain? any other climate challenges? For ships per se' I like wind. It is as clean as it comes. A BEV ship I am not in favour of. I dread to fathom how many tonnes of batteries of Lithium each ship will need and then the after end of life disposal challenge. Regardless of a green source being the prime mover large ships will still need some IC engine for maneuvering in port and confined waters - at least for the forseeable future. A lot of moving parts here.

Cross posting from an earlier post of mine with the photos.

Turanor PlanetSolar is the largest solar-powered boat in the world. In May 2012, it became the first solar electric vehicle (of any kind) ever to circumnavigate the globe. The 31-metre boat is covered by 537 sq metres of solar panels run two electric motors, one in each hull. There are 8.5 tons of lithium-ion batteries in the ship's two hulls. The boat's twin hull ie catamaran hull gives it a top speed of 14 knots (26 km/h) and a cruise speed of 10 knots (18 kmph). In 2013 she crosed the Atlantic back and forth. All this on solar power only.

Displacement: 85 tonnes
Length: 31 metres (35 with panels opened out)
Beam (or width): 15 metres (or 23 with panels opened out)
Top speed: 26 kmph (or 14 knots)
Engines: Electric Motors -2 x 60 kw for speed and 2 x 10kw for cruising
Fuel: Solar energy
Range: limited by crew endurance and food supply!!

The panels open up at sea as shown in the first photo and close up when coming into port and berthing alongside. Think of Karl Benz in 1885 or the Wright flyer in 1903 or the first flight on jet engine power in 1939 by the Heinkel He-178. These are all signals of great change over the coming 30 years.

[Jeroen]

thanks for putting up this thread. It will be interesting to see how the propulsion of ships evolves over time.

The idea of these wind turbines as sails/propulsion has been around for quite some time. I believe there are a number of these vessels around, although I don’t think I have ever come across one yet in real life. There are also a few vessels that use massive kites, to assist with classic propulsion. (sort of marine hybrid propulsion)

I agree that at least in theory ships have a lot going for them when it comes to electric propulsion. Further development of battery technology is likely to make it more feasible and more economically.

Maybe as an additional thought here; e-yachting! Here in Europe there are a number of commercial yacht builders that produce e- motor yachts. In particular the sort of recreational types that are used on small lakes and canals. In the Netherlands alone there are tens of thousands of motor yachts under 15m length.

https://www.greenlinehybrid.com/en?g...4aAudFEALw_wcB

Here in the Netherlands, we have a few areas where boats with IC engine are completely forbidden. You need to go electric!



Have a look here: https://www.boatrental-giethoorn.eu

And of course, we already have many electrical “pontjes” (small ferries crossing canals/rivers).

We live next to Gorinchem, a small provincial town on the river Waal/ Merwede. We have a number of regular ferry rides across the river and the ferry company has commissioned two fully electrical ferries to be commissioned later this year:



https://www.ad.nl/rivierenland/zicht...eer~a516988cb/

Not sure how big a problem it is in India, but in many coastal towns that receive cruise ships, the ship generators tend to be some of the biggest polluters!!

https://www.transportenvironment.org...s-cars-–-study

And again, electrical solution are already being provided; Hook of Holland is home to StenaLine Ferries. A few years ago they installed shore power for all their docked vessels. Massive reduction in emission! Cruise ships tend to draw even more power than these Ferries (and these happen to be the largest RoRo vessels in the world). The problem is not so much the technology. These cruise ships often dock close to city centres (E.g. Rotterdam, Amsterdam, Venice)

It is very complex and hugely expensive to put a shore power connection in place. Bad enough on an industrial estate, but inside a City peripheral a real pain. These things draw huge amounts of power and will require additional substations, cables and even additional capacity on the grid!

Jeroen

[srini1785]

Engines: Electric Motors -2 x 60 kw for speed and 2 x 10kw for cruising

A bit surprised by the specifications. For comparison, Ather 450x has a motor that has a peak power of 6kW (rated 3.3kW) for a scooter that weighs 108Kgs.

I have no knowledge of naval propulsion systems.

[condor]

Originally Posted by V.Narayan

Oceanbird might look like a ship of the future, but it harks back to ancient maritime history -- because it's powered by the wind..

I think those "sails" will be collapsible ? Else I dont see how will the ship remain stable during storms. And in such times, it would need to be powered by battery ?

[V.Narayan]

Originally Posted by srini1785

A bit surprised by the specifications. For comparison, Ather 450x has a motor that has a peak power of 6kW (rated 3.3kW) for a scooter that weighs 108Kgs.

I have no knowledge of naval propulsion systems.

Sounds right. Two factors about propulsion in water - (i) the weight of the ship is borne by the water entirely. So you are pulling not a 20,000 tonne ship {as we would understand it on a land vehicle} but the hull resistance largely; and (ii) as speed increases power needed increases by a cube function. So 8 knots needs 27 times the power that 1 knot needs.

For example INS Viraat the recently decommisioned Indian Navy carrier would need 10 horsepower {you read that correct} to be propelled at a little less than 2 knots {~5 kmph}. It displaced 28,000 tonnes. Diesel Electric submarines typically carry a cruise electric motor rated in a few tens of kW's that typically move these 1500 to 3000 tonne vessels underwater at 2 or 3 knots.

[Kosfactor]

Water and electricity - who would have thought!!

Cargo ships are very efficient as is - a propeller direct drive from the diesel engine`s crankshaft, spins slowly and carries huge amounts of cargo. It makes everything accessible around the world for cheap.

I thought why not increase the efficiency of this prime mover further by going for a turbine engine and then it occurred to me that Boeing and Airbus already have those in the sky.

Why bother those good old massive ships, let them be.

[V.Narayan]

Originally Posted by condor

I think those "sails" will be collapsible ? Else I dont see how will the ship remain stable during storms. And in such times, it would need to be powered by battery ?

Yes the sails are designed to fold in within themselves (telescopic) to pass under bridges or in stormy conditions.

Originally Posted by Kosfactor

I thought why not increase the efficiency of this prime mover further by going for a turbine engine and then it occurred to me that Boeing and Airbus already have those in the sky.

Specific fuel consumption wise a MTU diesel would be about 50% better than a marine gas turbine fitted on a ship. Marine diesels rock :-)

[Jeroen]

Originally Posted by V.Narayan

Y. Specific fuel consumption wise a MTU diesel would be about 50% better than a marine gas turbine fitted on a ship. Marine diesels rock :-)

Yes they do.

Where the marine gas turbine comes into its own is in power to size/weight ratio. So it can pack a really big punch in a very small and relative light weight package.

The other advantage is the gas turbine do not require much warm up time. You start and almost immediately can go to full power. Try and do that on a big Medium Speed Diesel and you are going to crack the cilinder liners or worse for sure.

Both aspects means they are often seen in military/navy type of applications. I have sailed with them on Anchor Handling Tugs where they drove the water cannons for fire fighting on oil rigs.

Jeroen

[rrsteer]

Was involved in a piece of work for a EU shipping major on future fuel trends for the shipping sector. Fuel here included everything. The broad conclusion was that LNG and biofuels will be most prevalent for the next 10 -15 years, as alternate fuels. After 2035, some bio-LNG and Hydrogen/ electro fuels was expected.

[dragracer567]

Thank you for this interesting thread! Already electric ferries have become mainstream with the Norwegians taking the lead (I think we already have a thread on that). I offcourse am not an engineer but anything that pertains to renewable energy and sustainability interests me greatly.

The electric car revolution is inevitable while cities like Shenzhen have shown that it’s possible to change your entire public transport fleet to electric vehicles. So, the next great frontier would be indeed in the field of cargo ships and planes. A friend of mine who is in the merchant navy described the shipping industry as relatively conservative and resistant to change as compared to other industries which in the end of the day could be a bigger barrier than the viability of the technology itself.

[Jeroen]

Originally Posted by srini1785

A bit surprised by the specifications. For comparison, Ather 450x has a motor that has a peak power of 6kW (rated 3.3kW) for a scooter that weighs 108Kgs.

See V. Narayan comments earlier. On boats to double the speed you need to triple the amount of horsepower. That applies for what is known full displacement ships. So boats/yachts that don’t plane (like a speedboat)

But there is also a maximum hull speed. Adding more horsepower will not make the boat go faster. The maximum hull speed is heavily depended on the shape and ratios of the hull (length, width, depth, shape etc)

But on a full displacement boat you will often find that they cruise happily around 25% of the max HP. And going to 100% (so four times as much) only just doubles the speed.

It works out different for planing hulls

Jeroen

[RadixLecti]

Originally Posted by Kosfactor

Water and electricity - who would have thought!!

Cargo ships are very efficient as is - a propeller direct drive from the diesel engine`s crankshaft, spins slowly and carries huge amounts of cargo. It makes everything accessible around the world for cheap.

I thought why not increase the efficiency of this prime mover further by going for a turbine engine

In a way, the vessels I sail on do exactly that, though not in the way you might imagine. And not by using a turbine with a dedicated combustor.

We have two relatively large two-stroke low-speed diesels, and what is known as a turbo-compound generator powered by the exhaust gas (both directly into a power turbine, and indirectly, by using steam generated from the heat in the exhaust gases in a separate steam turbine - the two being coupled by a clutch and gearbox) which produces a significant amount of electricity. When the amount of electricity available exceeds the amount required for the ship's systems and cargo, the excess is fed to the propellers via large electric motors which are mounted on the propeller shafts.

While this greatly increases the complexity of the machinery plant, overall plant efficiency can reach 60% in optimal conditions, and the vessel's diesel generators only run in port, at low speed, and when they are needed to provide additional boost to help the main engines via the aforementioned electric motors.

As for battery power, I think it will be some time before the penalty in weight and space (compared to the energy density of fuel oil) make it worthwhile for large vessels such as mine.

My employer is however currently testing a large battery pack to use in a sort of hybrid configuration, where the battery can assist the generators during large and rapid load changes, such as when using thrusters.

On the main engine front, here are basically two manufacturers of large engines for these ships, and one of them is pushing both ammonia and methanol generated from renewable energy as a route to carbon neutral shipping.

https://www.man-es.com/discover/two-...ammonia-engine

I know for a fact that ammonia is one of several options under active consideration by my employer.

Batteries, ammonia or methanol, I hope I am still sailing when the next big change in marine propulsion comes, so I can experience the new equipment first-hand.