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Largest cargo sailboat completes first Atlantic crossing

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Re: Largest cargo sailboat completes first Atlantic crossing

#191
post #89

Earlier quoted context omitted.

I crossed the atlantic twice, each time for 650 euros the 13 days… add 250/300 euros for internet

Have long been interested in something like this. From where to where? How did you arrange the trip?

The easiest way to do it is on a repositioning cruise where at the end of the season the cruise lines take their ships from one market to another. The positives are a cheap cruise, the negatives are that you're right at the end and beginning of ideal seasons so your experience at each end might not be great. Also you'll have a lot more sea days and fewer port days which could be in either column.

Weather at sea can be considerably worse than coastal weather. Cruise ships are pretty stable and it's unlikely to be awful, but plenty of people do get seasick. I used to be a professional sailor and so obviously can't see what the fuss is about, but probably half the passengers I spoke to felt ill on at least one of the days, and a few people spent the entire ocean transit in bed. If you're prone to motion sickness take some medication with you.

The atmosphere is different to regular cruises. Typically less of a party and the clientele skew towards older and more independent travellers.

To answer your actual question - go to cruisemapper and seascanner and you'll find them easily enough. They're all over the world.

Re: Largest cargo sailboat completes first Atlantic crossing

#192

Napkin calculation: The Neoliner Origin cruises at 11 kts (20Km/h). "Straight line" on Google Earth from Saint-Nazaire to NY is about 5300 Km, so it crosses the Atlantic in 18 days. The Emma Maersk (which I am aware plies a different route, but just for comparison's sake) cruises at 25kts (46Km/h) and therefore takes about 5 days.

For comparison, I calculated the J/(kgm) for both the Emma Maersk (at the numbers I could find in the Germany Wikipedia article; they seem to be for higher power levels with less efficient hydrodynamics) and a generic battery electric truck like a Mercedes E-Actros ("1kWh/km"; realistic net payload on/in trailer: ~20t): Emma: 0.0406 J/(kgm) E-Actros: 0.18 J/(kgm)

If we'd only carry modern LiFePO4 at 150 Wh/kg, their range (at zero remaining payload) would be: Emma: 13300 km E-Actros: 3000 km

Thus while a substantial payload mass fraction, the heavy engine could be mostly avoided (the Emma's main engine has a specific power of about 34 W/kg; contemporary power-dense electric motors/generators around even just 1 MW are slightly above 10kW/kg; a factor of 300).

IMO rather look at whether the approach to battery packs of Form Energy allows for this level of specific energy, and if so, how to hook container crane swapped battery packs to the ship's electrics. If that's too heavy, see how such a ship could be plugged in while in port with 1000 contemporary E-Actros worth of charging power (400 MW instead of 400 kW; gives 1 day recharge after 5 days at sea). By the time that's solved, batteries have gottwn cheaper. Those 5 days of battery capacity would cost in the high triple digit million USD today; for comparison, the Emma build cost inflation-adjusted around 233 million USD today.

A container train on flat track in Europe seems to be rated to 0.15 J/(kgm) while being grid powered, over twice as fast as the Emma (also faster then the truck), though that consumption is what the traction system needs to be rated to to reliably make the train schedule; fleet efficiency should be much better.

Sadly there's oceans either side of north America unless you want to take a great circle through Alaska and Siberia or through Greenland and Norway.

Re: Largest cargo sailboat completes first Atlantic crossing

#194
post #140

In the meantime, China is constructing nuclear cargo ships ([1], [2]) that will be able to transport 14,000 containers at full throttle (200MW) without a need to refuel for years. Obviously, it's still not done, and yet to prove to be profitable, but their reactor design does suggest that they have a chance to make it work and replace a lot of CO2 emissions. 1. Original article, but paywall: https://www.scmp.com/news…

How ironic, a huge "EMBRACING NET-ZERO FUTURE" logo on the behemoth filled with cheap plastic crap that will chill out in landfills for generations to come.

Re: Largest cargo sailboat completes first Atlantic crossing

#195
post #190

Just wondering if there is any potential for coasting with these smaller ships? Replacing lorries for port to port travel say in med or along Atlantic coast of Europe. Coasting ships were the main cargo transport before trains and for some time after in the UK. Even as late as 1950s a fair percentage of cargo came in and out of London on relatively small ships from UK ports and Europe mainland. Before containerisatio…

The problem is always multi-modality.

Switching modes of transport increases cost and complexity.

The volumes also needs to be very large for it to be worth it.

Switching from just point to point trucking to truck -> ship -> truck needs to have extremely large efficiency gains in the ship portion to be worth it.

Re: Largest cargo sailboat completes first Atlantic crossing

#196
post #49

Earlier quoted context omitted.

You're really missing the point. The volume of cargo carried by sailing vessels in the old days was orders of magnitude lower. Not even remotely comparable to the current global trading system. Customers care about total cost, not just fuel. There is also crew wages, maintenance, insurance, capital depreciation, etc. Sailing vessels that carry useful amounts of cargo are much slower than equivalent motor vessels so a…

> The volume of cargo carried by sailing vessels in the old days was orders of magnitude lower. Surprisingly, no, it wasn't. I'll slightly fudge the numbers and talk in terms of proportion of world trade that was carried by ocean-going vessels (because if you double the population then it's reasonable to talk about doubling the number of ships). The world economy was very globalised in 1913. That level of globalisati…

Show your work. Without numbers, those are all just assertions. And the assertion that the world's economies were more globalized before WW1 than after the Cold War is particularly dubious.

Re: Largest cargo sailboat completes first Atlantic crossing

#197
post #121
post #51

Earlier quoted context omitted.

How much sail area would it take to move a 20000 TEU ship at, let's say, even 12 kts? How tall would the masts have to be? Would they fit under bridges? You guys are talking about total fantasies here.

> Would they fit under bridges? You do realize that none of those ships could get into any port, right? We've made modifications to accommodate that. I tend to agree with you that putting a fixed sail on top of a container vessel won't fly. Maybe ships would need to be smaller. I think the size of ships was mostly increased because it makes it more efficient. But if fuel is free, you could have smaller ships take dir…

> I tend to agree with you that putting a fixed sail on top of a container vessel won't fly.

Of course it won't, it's not an airplane.

Re: Largest cargo sailboat completes first Atlantic crossing

#198
post #31
post #20

Earlier quoted context omitted.

There’s more than enough energy in the wind, and modern sailing technology has come a long ways. Some modern recreational sailboats can cross an ocean as fast as a cargo ship on just wind power, and speed isn’t even much of a factor for a lot of shipping. With the right tech I think fuel free shipping can disrupt fossil fuel shipping just by being cheaper. Back when engines first replaced sailing fuel was nearly free…

Bullshit. We're not talking about recreational yachts here. There is not enough energy in wind alone to move huge merchant vessels at economically viable speeds across oceans.

It is much harder to get consistent high speeds on a smaller sailboat than a larger one. Back in the “golden age of sail” the highest cargo capacity sailboats were also the fastest. It will absolutely require new boat designs and engineering to create massive modern shipping boats, but the fact that recreational boats can sustain high speeds across oceans at small scales proves it is possible at larger scales needed for shipping. There absolutely is a lot more energy in the wind than you need for this.

Even with old sail tech it was already closer than you might expect to modern container ships. Look up the Preussen, launched 1901. It could do over 20 knots and carry 8,000 tons of cargo. Although small by modern standards, there are economical viable smaller container ships operating today in that speed and cargo capacity range.

Even if you still had an old low tech boat like the Preussen nowadays, modern sail technology and hardware, plus better weather routing data would make it substantially faster, and require a tiny fraction of the crew that was initially required.

Re: Largest cargo sailboat completes first Atlantic crossing

#199
post #140

In the meantime, China is constructing nuclear cargo ships ([1], [2]) that will be able to transport 14,000 containers at full throttle (200MW) without a need to refuel for years. Obviously, it's still not done, and yet to prove to be profitable, but their reactor design does suggest that they have a chance to make it work and replace a lot of CO2 emissions. 1. Original article, but paywall: https://www.scmp.com/news…

How ironic, a huge "EMBRACING NET-ZERO FUTURE" logo on the behemoth filled with cheap plastic crap that will chill out in landfills for generations to come.

How ridiculous they're solving one part of the problem when other parts aren't solved.

Re: Largest cargo sailboat completes first Atlantic crossing

#200
post #78

This ship carries 5300 tonnes of cargo. The average transoceanic container ship carries around 150,000 to 250,000 tonnes.

Does anyone know how well this scales? I assume it just doesn’t make sense to actually make one of that size when they are testing out the concept.

I did some searching around for this (not a subject matter expert).

Basically the sail area grows with length squared, but ship mass and resistance grows roughly with length cubed. So propulsion gets weaker with size.

To move a full sized freighter, you would need a mast the size of a skyscraper and we don’t currently have materials that can support that.

If we did have a material that supported sails that large, it would still be a problem because you are functionally making the ship top heavy (when wind is applied) increasing how likely it is that the freighter rolls over.

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