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Battery-Powered Ships Next Up in Battle to Tackle Emissions (bloomberg.com)
52 points by howard941 67 days ago | hide | past | web | favorite | 51 comments

It only operates in Tokyo bay to answer the first question that everybody is going to have.

Transatlantic and transpacific container shipping is still going to be among the last sectors of the economy to be electrified.

It's probably more practical to build modern sailing ships than to try to electrify bulk overseas cargo shipping. Or maybe a hybrid approach where the sails are also lightweight efficient hardy cheap solar cells that turn electric motors to add a few knots to the speed during the day.

But even then you need massive energy storage to make sure you have power to maneuver in a storm.

It's probably more practical to build modern sailing ships than to try to electrify bulk overseas cargo shipping

Back in the heyday of the battleship, replacing the engine was one of the things it wasn't worth doing. It's so hard to do, you might as well just build a new ship. I have no idea if this is still true, or not. Construction techniques have come a long way. Today, there are cruise liners that have all of their propellers in multiple swiveling pods containing electric motors. (They generally have generators run by diesel or steam turbine.)

The lifetime of a modern ship is only 25-30 years. I think when the parent comment mentioned electrifying bulk cargo shipping,they were referring to building new electric ships, not converting existing ones.

It is absolutely still true, most ship engines are not removable without breaking the hull above the engine. If you're going to do that, it's often easier to start fresh.

It is absolutely still true, most ship engines are not removable without breaking the hull above the engine.

Seems to me, especially with electric engine pods, ships can be designed to allow the replacement of the engine/generator.

They can be, but the ones that are currently afloat haven't been.

Shipping companies have had decades of success fighting against legally-mandated retrofits - double-hulled tankers, trivial safety features for passenger ferries... I don't think your idea of replaceable engines is going to get any traction.

Totally depends on the industry niche. As always the low margin guys will repair/modify and the high margin guys will buy new hardware.

Oh I don't know, Japan did it a few times with the Fuso and her sisters. Even the Italians did it with a line of battleships.

The debate back in the 30s was if diesel could take the place of steam turbines but they ended up weight prohibitive and some maintenance would be similar to the work required to just swap engine types

The depends on what you mean by "engine." Big diesels are relatively new in the maritime world.

On a steam ship, which had a much less monolithic power plant, replacing an engine or a boiler was feasible. Replacing reduction gears usually was not.

Re-engining a jetliner often means designing a whole new airplane, too.

The long term solution will be to run most large ships on synthetic liquid hydrocarbon fuel manufactured on shore using renewable power. Sails and onboard solar power can help a little but the gains will be marginal.

Solar could work on very big multihulls. Or perhaps unroll a solar tail.

Solar would work on existing ship designs like container ships.

Moving through the water is very efficient - if you go slowly enough. If ships travel slower than the hull displacement speed, they could travel on electric motors and solar power today.

The challenge is convincing global markets that slow shipping is worthwhile, when everything is moving in the opposite direction (faster and faster).

>If ships travel slower than the hull displacement speed, they could travel on electric motors and solar power today.

Check your math here... it doesn't work out. Most large ships DO travel at less than displacement speed, going faster would take more energy than their engines produce.

Even covering an entire ship's deck with present solar panel technology, the ship couldn't run on the panels... they would have to charge a battery bank, then when full the ship sails a certain distance, stops, recharges, and repeats.

The only practical means of powering modern ocean going vessels given their range and size are fossil fuels or nuclear reactors.

If you can get by with sails for some things, that's great, but unless someone starts building massive numbers of sailing vessels, there's not going to be enough of them to replace motorized shipping, and even then some routes and cargoes won't be able to ship that way. Some cargoes are perishable, for instance.

Any plan anyone comes up with for fighting climate change will fail if it requires a significant portion of humanity to change its behavior all at once.

Slow shipping is already a thing. For example, many companies will decide to send their cargo around the capes instead of paying the associated fees to go through the panama/suez canals.

Mærsk’s Triple E-class, some of the largest container ships in the world, do use the Suez Canal to transport goods between Europe and Asia, but are slower than previous classes, with a design speed of 19 knots.


Developments like air support hulls - https://www.youtube.com/watch?v=04KnXJTRRYk - are another possible way to go if you want efficiency and a bit of speed.

Do the math. Solar won't produce enough power to move the ship at a useful speed. Container freighters have minimal space to even install panels. And multihull designs are impractical for cargo handling.

Four air support hull container ships and a detachable square kilometer of panel, that can fold up and floats on pontoons, is where the maths is leading me currently. :)

I hope you're joking? That would never work in any kind of rough weather, or in a congested port.

>I hope you're joking?

Idly musing on what it level of nonsense it might actually take with current tech, would be the best description. The panel would have to fold up and detach from the container ships, becoming a separate vessel, for rough weather, ports and canals.

I did say a very big multihull.

edit - suspending a power rail underwater for electric container ships to link to, powered by a corridor of floating panels, is another potential approach.

That or fusion.

Or fission...

See also the NS Savannah, the first nuclear-powered merchant ship.


Fission isn't practical for merchant vessels. Several large ships sink every year due to severe weather, structural failure, cargo shifting, etc. And there's no way to protect those ships against terrorist attacks.

Use fission plants ashore to create synthetic liquid hydrocarbon fuel for ships.

Fusion (if it ever works) will be too large and complex to use in merchant vessels.

Fission hasn't been practical in the past using old reactor technology.

Climate change makes a big difference in the equation, though. Marine nuclear power is one of the best understood, safest areas of nuclear use that exists, even using the old technologies.

The idea of using "modern sailing vessels" for shipping in the amounts that are presently moved from continent to continent is just plain nuts. Unless most of the world is willing to go back a hundred years in technology, we're going to need to use motor vessels going forward.

About the only way to eliminate all carbon emissions from large ships is to make them reactor powered. Batteries will work for short trips, but if you combine the need for long range and high power in shipping of large cargoes, the only way to power ocean going vessels in any practical sense are internal combustion engines running on fossil fuels or steam generating reactors powering turbines.

That's why the navies of the world run on one or the other.

New fission reactor technology won't change anything. Only the US Navy has a good safety record with nuclear vessels; the Soviet / Russian Navy has had multiple serious accidents with sinkings and radiation releases. And the only way the US Navy succeeded was by using a huge amount of resources under tight top-down control. None of that is possible in the merchant fleet. Plus the Navy has built in armed security forces. Any modern nuclear merchant vessel would need armed, trusted security guards to protect against terrorist attacks (just like nuclear plants ashore).

In short, nuclear powered merchant ships are never going to happen regardless of the potential advantages.

Both navies have had incidents where nuclear powered submarines sank. That's the nature of the military, they tend to go places other ships don't.

> the only way the US Navy succeeded was by using a huge amount of resources under tight top-down control.

Everything in the military is done with tight top down control for the most part. That's not why it succeeded, though. The military is the only organization that did it since it's the only organization for which nuclear wasn't constrained by the need for profit.

There was a demonstration nuclear cargo vessel built that operated for four years, but they weren't mass produced and so weren't economically viable when oil was cheap.

However, if you combine the need for lowered emissions with the higher modern price of oil, larger scale production of nuclear civilian vessels begins to make some economic sense.

This is aided also by the fact that modern reactors could be designed to be lower cost to operate.

Security wise, nuclear powered vessels would be less vulnerable than oil powered vessels presently are because they'd be at least as fast and would need refueling less often.

They would not be a more attractive target for terrorists than other ships despite nuclear propulsion, because the reactors can be designed to be tamper proof, meaning the only thing a terrorist in possession of a nuclear ship can do is sink it with little resulting fear or hardship for the country they are trying to affect. Water blocks radiation very effectively, and ships with sunken nuclear reactors don't spread radiation around, they contain it.

The security risks are primarily in port, plus insider threats. Do you really think that most nations would ever allow nuclear powered merchant vessels crewed by random foreigners to enter their ports? Regardless of the potential benefits it's just completely unrealistic in the post 9/11 world.

Theoretically one of those hypothetical sealed thorium reactor designs might be suitable and safe enough for a merchant ship, but it's a hard thing to sell while oil is still cheap.

Having one of these ships sink is not as terrible as you might think. Water is an excellent moderator and these very heavy elements will tend to stay on the ocean floor. There's a reason we store nuclear waste in big swimming pools.

Cargo ships are currently using diesel engines that weight up to 2,300 tons and carry more than 15,000 tons of fuel.

The ITER core currently weighs about 5100 tons. I'd expect refined fusion systems to be able to come down in weight. Even if all the supporting infrastructure weighed more than the combination of bunker oil and diesel engine, it'd have to be a lot more to negate the advantages.

As far as too complex, that really depends on the commercialization potential of fusion and how complex final designs are.

> synthetic liquid hydrocarbon fuel manufactured on shore using renewable power.

Whether the liquid hydrocarbon fuel is synthetic from renewables or natural (dug out of the ground), burning it will still give off greenhouse gases.

Synthesis is only carbon-neutral if the synthesis method involves capturing those greenhouse gases again.

I think the point is that the carbon in the synthetic fuel came out of the air. So, yes, you're correct that burning it gives off greenhouse gasses, but the idea is that the net effect is much smaller than taking carbon out of the ground and burning it.

Yes, the problem with shipping is that batteries just don't hold enough energy for such a long trip. It might be that hydrogen fuel cells charged by renewable energy will be the long-term solution.

Yea, ships are one of the few areas where hydrogen is actually a very good fit. But, no need for fuel cells as straight up IC engines have similar efficiency at these scales.

Spot on

> Transatlantic and transpacific container shipping is still going to be among the last sectors of the economy to be electrified.

It probably boils down to energy density, plain and simple.

For ships? Weight of batteries shouldn't be a big issue with ships. They could be used as ballast, for example.

Weight of batteries is a big issue with ships. Vaclav Smil calculated diesel is 20x dense, turning 5000t diesel fuel for Asia-Europe trip to 100000t battery which is not economical.


I wonder if a hybrid can reduce that problem, i.e. a hybrid battery/sail, or even a hybrid battery/windmill system.

A windmill would help both push the ship and generate power to the batteries.

I recently saw this Fully Charged video about a short, but very frequent, ferry crossing that is now fully electric, with automated charging at both ends of the trip

The scale here is enormous, and just for a 4km journey


And the new Norwegian ferry Color Hybrid was recently delivered. Not quite twice as large (2k pax, 0.5k cars). Similarly-sized 5-ish MWh batteries, plug-in or diesel-electric. Electric operation around ports, to minimize pollution, and hybrid or diesel elsewhere.

Lots of ships run on bunker fuel, a cheap refining fraction nobody else can use. Those 3 story diesel engines are a different breed wherein "one massive container ship equals 50 million cars"


In terms of global warming potential, they are nowhere close to that. The "50 million cars" statistic is specific to the SOx output of the ships (sulfur oxides). These cause local impacts (breathing issues, view haze, damage to plants etc) and wide impacts (acid rain) [1]. Because of the strong local impacts, fuel grades for cars, trucks, etc had strong reductions to sulfur content, but ships did not (though often they are required to use more expensive, more refined fuel in port or 20km of shore or what have you).

All this to say, these ships do create super high emissions of Sulfur Oxides, but their CO2/equivalents emissions are quite low (the lowest per kg*km of any means of transport! [2] ). Worth addressing, but not nearly the equivalent of 50 million cars in the "emissions" that the common dialogue refers to.

[1] https://www.epa.gov/so2-pollution/sulfur-dioxide-basics

[2] https://www.theguardian.com/sustainable-business/2014/aug/01...

With bunker oil some fraction of a percent of generated power comes from burning the sulfur. Tells you much what you need to know about that.

And yes it's very interesting to look at transport modes by hp per ton. You find that ships, trains, and trucks requirements are modest compared to passenger cars.

Sounds like someone is going to have to build a network of depth chargers :-)

The world's largest hybrid ferry [1] has just been launched to run between Sandefjord (Norway, on the West coast of the outer Oslofjord) to Strömstad (Sweden, on the Eastern side of the Oslofjord) [2]

[1] https://www.ship-technology.com/projects/color-hybrid-ferry/

[2] https://www.colorline.com/sandefjord-stroemstad

Slightly further North the much shorter Horten to Moss route across the Oslofjord will be fully electric in 2021 [1]. Though with much smaller ferries.

[1] https://www.ferryshippingnews.com/enova-contributes-nok-31-m...

I wonder if it's practical to stick a couple of Space Shuttle external fuel tank-sized liquid hydrogen tanks on a typical container ship and then run it on hydrogen. One of the problems with liquid hydrogen (not the only one) is that it's impossible to keep it from slowly off gassing. However, if the tank is large enough it would off gas slower than your engines would be consuming the hydrogen.

These should come in handy in retrofits: https://www.nextbigfuture.com/2009/01/365-megawatt-supercond....

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