How to design a sailing ship for the 21st century? | Hacker News Reader

How to design a sailing ship for the 21st century?

solar.lowtechmagazine.com

115 pointssealeck88 comments

> Lithium-ion batteries are very compact, but they cannot be considered sustainable and bring safety risks

C'mon this is silly. The dominant safety risk of a small vessel (and all of these are small in modern terms) is capsizing in heavy weather, with the loss of all hands.

LiFePO batteries, built into a bank with really excellent waterproofing, would be quite adequate to the job. If lithium battery technology in general proves to be unsustainable, we may as well pack up and go home, because decarbonization isn't going to happen.

Taking the average specific energy of LiFePO from Wikipedia, we get 12.5kg per kWh, almost five times denser for a proven technology you can buy off the shelf. 4.4 tonnes for the larger battery, compared to 9 tonnes for the smaller saltwater battery sketched out in the draft, and 21 tonnes for the larger one. That's 16.6 tonnes of additional life support the ship can carry; stowing a ship is a classic knapsack problem, there's no such thing as an "acceptable" amount of tonnage and volume to leave out of the equation.

Using saltwater batteries here would be an ostentatious stunt. Arguably that's what this whole thing is: an ostentatious stunt. But it doesn't have to be, it's a good proving ground for much larger sail ships, and a thousand tonnes here, a thousand tonnes there, pretty soon you're talking about real cargo. Electricity requirements should be very much sublinear with cargo capacity as well.

I've never sailed in blue water, but I thought that modern weather and navigation infrastructure mean bad weather can be largely avoided. Either way fire on board is still something to be avoided.

Major storms can move faster than most sailboats can sail out of the way.

The electricity still must be distributed around the ship.

Proper weatherproofing can easily make the battery the least likely point of failure in the whole system.

Sure modern motorized merchant vessels generally route around major named storms (except for rare tragedies like the SS El Faro). But if you want to carry cargo reliably for paying customers then you're going to have to sail into bad weather occasionally. Winter weather in the North Atlantic is usually bad and can change quickly. There's no avoiding it.

Not a sailor nor a maritime expert by any means, but IIRC Japan now has submarines that uses lithium-ion batteries to power submerged movement. Granted it is mil-spec.

Yep. https://www.popularmechanics.com/military/navy-ships/a344285...

I think for ships of this size, fire is a bigger risk than capsizing.

> If lithium battery technology in general proves to be unsustainable, we may as well pack up and go home, because decarbonization isn't going to happen.

Exactly.

Lithium is not that uncommon. It's just that the reserves that we have found (so far) where nature helpfully decided to concentrate it for us are not very common. If we don't use those, then it's expensive to extract (both in money and energy). That's another argument for expanding renewables. Put them to work to extract lithium from salt water.

Oil had a very similar argument, but we keep finding reserves and devising ways to use previously uneconomical reserves.

Now, once extracted, we recover most of it when it comes time for recycling. I bet older marine batteries would have plenty of uses as second-life energy storage for stationary applications. It may take decades until we even have to recycle them.

> safety risks

As for the safety risks... One of the main ways to contain a battery fire is to spray water on it. Is ocean water is too salty(therefore, conductive) for this application?

Wonder if you could design the battery to be ejectable - you'd want some way to get them in and out anyway.

In the event of a fire just dump it overboard.

I guess the usual problems apply, you can't eject underwater without a pressurised system (now we have a torpedo launcher) and you can't eject over the waterline because you want the battery low for center of mass/center of bouyancy.

Kinda funny image though "Launch Ze Batteries!"

Most yachts are switching to LiFePO, because they perform so much better than any lead-based batteries. Haven't heard about safety issues.

I still remember someone demonstrating the relative safety of LiFePOs by driving a nail straight through one in front of me.

The LiPo immediately started smoking and within a few seconds erupted into flame, the LiFePo (an A123 cell) didn't really do much of anything at all, other than no longer functioning.

> If lithium battery technology in general proves to be unsustainable, we may as well pack up and go home, because decarbonization isn't going to happen.

Nuclear + Hydrogen would still be available.

> However, by definition, the sailing ship is not a carbon neutral technology. For most of history, sailing ships were built from wood, but back then whole forests were felled for ships, and those trees often did not grow back.

I do not understand this sentence. If I cut down a tree and do not burn it, isn't it a carbon neutral process? It did not release any carbon into atmosphere. By this logic is there any material to use to build something which is neutral?

The tree is no longer alive to photosynthesize co2.

It only takes up Co2 in its growth phase, not afterwards.

That seems intuitively true, but apparently it's still debated whether old- or new-growth forests are more carbon-negative.

It is really only a debate about when exactly trees stop growing and consuming CO2. Given enough time, sooner or later the tree isn’t consuming CO2. At that point there is no point in leaving the tree standing. Cut it down and let a new tree grow there.

Yes, but a tree that isn't growing isn't trapping much carbon dioxide either.

A tree cannot live forever. Once it is dead all (or almost all) accumulated carbon slowly released back into atmosphere as CO₂ by bacteria. So cutting trees and preserving them from decay is a carbon negative process in a long run.

how is it carbon negative? wouldn't it be neutral? unless the trees were sent underground to prevent release into the atmosphere? or became petrified?

Correct: to make a change we would have to bury millions of tons of valuable wood deep enough that the co2 stays trapped. In short, it would be the opposite of extracting and burning oil.

If I keep cutting down and re-growing trees on the same plot of land over and over again I will reduce the total CO2 in the atmosphere as long as the cut down trees are not burned or rot. You can avoid that by building houses for instance. Or boats.

That what I meant in my comment, but over long enough time frame it will be a carbon neutral process: a building will eventually fail into disrepair and will rot or will be destroyed by a fire. A ship will likely last even less.

Anyway I see no reasons to avoid using wood if it is harvested responsibly.

The thought could be that in "tree form", the material contributes to the net uptake of carbon from the atmosphere, so once it is harvested that negative flux on the balance sheet shifts equilibrium more towards lower or net negative uptake. It's relative.

That's not true though, the tree stop growing at a certain point and is really carbon neutral until it dies and decays into the ground and new ones replace it.

By removing trees and planting new ones, this process is sped up and more carbon is removed from atmosphere.

During the age of sail most of those forests were cut down and turned into farms or pasture-land. So there was a net increase in carbon emission just from the expansion in human activity.

If you were going to build a farm there anyway, then it’s better to build a ship out of that wood than to burn it down.

It will eventually rot and release its captured carbon.

All trees, even those which are not cut down for constructing a sailing ship, also eventually rot and release most of their captured carbon. Only those which are burned efficiently in a high-oxygen environment turn completely into CO2.

In a natural forest, it's true that a tiny fraction of this biomass derived from atmospheric CO2 rots incompletely on the forest floor and is turned into a small amount of carbon-rich soil, but this process is glacially slow. [1] suggests single-digit grams per square meter per year. Rotting on the seafloor may or may not be any better or worse.

Relatedly, carbon sequestration projects have biological carbon intake as one option. Instead of using industrial-scale chemical or electrical reactions to pull carbon from the atmosphere, use photosynthesis. Grow some trees, process them into ethanol and graphite, and bury the carbon-rich waste forever.

[1]: DOI:10.1007/978-3-540-92706-8_11 https://www.researchgate.net/publication/225314103_Soil_Carb...

Tree contains X Co2 => Tree gets cut down without replacement => ship gets made and rots => X Co2 releases into atmosphere. Net Co2 = +X

Tree contains X Co2 => Tree dies => New tree grows in opened up space. Net Co2 = 0

Why do you assume the tree would not be replaced, we plant more trees than we cut down nowadays for example. The only reason to not replant the tree is if the land was being used for something but then the tree would have been cut down anyway ship or not.

The original quote at the top of this thread says that ships were build from trees that were felled _and not replaced_. The discussion started from that assumption.

Anyone interested in a fair comparison should point out the error of that comparison. Using wood in a managed forest it’s not a bad thing. It’s greatly preferable to extracting coal and oil.

So what? That’s part of the natural CO2 cycle. The problem isn’t carbon dioxide. The problem is adding CO2 from fossil fuels. As long as there is a net growth forest there is no problem. Just make sure you replant trees cut down. It is more important that we start extracting coal and oil.

A human-managed forest and a naturally evolved forest are very different things. When we plant trees, it's basically another farm, rather than the rich ecosystem that was originally there and destroyed by us. They also have very different carbon dynamics. The only way to recapture that same level of carbon that the original forest had, is to "rewild" the land and allow a full, old-growth style forest to grow back, which takes a lot longer than just planting some fast-growing trees in straight lines.

Plus, it's my impression (it could be very effective marketing by the lumber industry) that lumber trees are quickly grown and chopped in farms and controlled logging. And the next tree is planted.

I'd guess that construction is probably a pretty good sequester for the wood/carbon in terms of length of service, and likelihood for controlled recycling or burial after its done.

The logging industry is likely incented to maximize the carbon sequestration rate: which is growing trees producing future lumber.

Yes, and it is not releasing fossil carbon.

"by definition" of what? Carbon neutral or sailing ship? Neither term is defined in the article, and neither interpretation makes any sense.

Finally, a proper look at the cost in most respects of the real cost of a 'sustainable' technology. We need more of these but no one will pay nor pay attention.

Unfortunately though, sail driven ships are kind of useless for the efficient movement of cargo. Masts are required and take away stowage space and, more importantly, make efficient cargo loading/unloading impossible. Read the book "The Box" to understand the changes brought about in cargo shipping over the last century.

Tanker boats could probably use sails without loading and unloading getting in the way. I would imagine it's just hoses and pumps to get the liquid out.

Exactly, and these are precisely the vessels that can most handle slower transfer speeds - as you just have more sailboats to make up for slower speeds/smaller sizes. All that matters is how many arrive each day, as the cargo is fungible.

In fact, doing such would provide a buffer that could help prevent supply shocks.

At what point does the additional resource of building a lot more ships (which have more crew, eating more food, producing more waste) result in a net negative?

Oceangoing ships have a relatively short useful life...salt water is rough on metal.

I suppose the upper limit would be when it’s possible to make an ocean-wide winch system and you can just hook barges to it and pull them across the ocean.

Just hook containers to it like cable-cars and move them across.

Instead of sails we could try other methods, like kites, or that weird turning-metal column effect. To name two serious proposals I've seen

I assume you’re referring to the Coanda effect.

I think rotor sails leverage the Magnus effect, not the Coandă effect.

Good news on the “weird turning-metal column effect” front: they just installed five tilting rotor sails on a newlybuilt bulk ore carrier.

https://gcaptain.com/newbuild-vale-vloc-revealed-as-bulk-car...

Why is this important? It shows that the ship owners has seen enough promise in the technology to overcome the potential risks. If it works out well for them we will very likely see wider adoption.

How does this work? The article assumes I should already know the mechanics of it, but googling only seems to turn up a bunch of the same sorts of articles.

I'm not an expert on it really. They rotate the giant cylinder and the wind is blowing by. The rotation forms a low pressure zone one side of the cylinder which acts as a lift force perpendicular both to the rotational axis of the cylinder and the wind.

It's the same effect which "turns" a soccer ball if you kick it with a spin. There is a really nice demonstration of the effect in this video: https://www.youtube.com/watch?v=2OSrvzNW9FE

This wikipedia page has a way better summary than my attempt above: https://en.wikipedia.org/wiki/Rotor_ship

From that article:

"If the pilot proves effective, it is estimated that at least 40% of the fleet will be able to use the technology, which would result in a reduction of almost 1.5% of Vale’s annual iron ore maritime transport emissions.”

Well, that's a step in the right direction so something to be applauded. But taken alone, an emissions reduction of "almost 1.5%" isn't going to save the planet.

> Two rowing machines could provide roughly 400 watts of power. If they are operated around the clock in shifts, they could supply the ship with an extra 9.6 kWh of energy per day (ignoring energy losses) – one fifth of the total maximum electricity use.

Any suggestions for an infinite climbing rope for extra electricity at home?

> Even a crew of 12 taking a daily hot shower would require 25.2 kWh of energy per day, half of what the hydrogenerators produce at a sailing speed of 7.5 knots.

Well, don’t take hot showers? Get warm with exercise and breathing, then use a little cold water and a soapy rag to get cleaner, then rinse in cold water. I wish I’d been doing this my whole life, for the mental, physical, and ecological benefits. What might a person suffer from that necessitates heated water for washing?

Solar water heaters are among the easiest renewable technologies available. It is literally as simple as a container for the water that is painted black. For something done professionally it is trivial to have a hot loop that keeps a well-insulated storage tank at temp. With a bit of effort you can even reclaim some of the heat from the shower waste water.

You might want to take a look at low tech magazine's post on shower technology ;)

I struggle with this whole article. It implies keeping a sailing ship labor intensive just with a few electric winches. Wing Sails seem like a better approach and I assume they are much less labor intensive.

You're spot on. I've followed this topic area for some years out of curiosity. Saildrone style wingsails only require a very small electric actuator to move a control surface. The control surface sets the overall net angle of attack of the assembly. The wing tracks the wind, only needing the control surface changed as the bow crosses the wind.

A system like this can be entirely labor free.

Tall ships on the other hand... I don't care how many electric winches you have, they'll always require massive numbers of people for sail handling.

Yup. OceanWings by VPLP https://www.hellenicshippingnews.com/vplp-design-signs-its-f...

Hundredrabbits are traveling on a sailor ship while working on OSS and many projects, they are also providing many informations about their 1982 boat and about sailing and how they are providing electricity from solar power etc..

https://100r.co/site/sailing.html

I sailed cape to cape on the Bark Europa in 2018, and while we did need to use the engines at times, there was a strong preference to sail under wind power unless absolutely necessary. Everyone in the crew was very much environmentally focused. On the point about warm showers... It's pretty cold down there around Antarctica!

I loved travelling with nothing but the wind powering us, and I'd prefer to sail over flying, preventing a lot of emissions. Unfortunately the world moves too fast now and we can't afford to spend months at sea.

https://www.youtube.com/watch?v=yP1f3Df6SXE

Maybe this kind of lifestyle appeals to enthusiasts, but I can't see modern unions allowing some of the dangerous work out on the sails.

aargh - this is a step in the expansion of humanity on a planet divided by vast oceans, a way of life, adventure and the actual elements of air, water and sun..

a union rule book is .. what? boring!

It's a nice case of how anything can be 'just a job' to the people doing it, at which point the people doing the work really want safety at work, even if to outsiders it looks like an adventure.

I see no reason why most of the sail work couldn't be automated and motorized.

Rigid wingsails make more sense than tall ships, unless you are looking for nostalgia.

Thanks for sharing this interview. I've seen about 10 minutes so far and I'm hooked. I just love learning about lives that are/were so different to mine.

Discussed few days ago: https://news.ycombinator.com/item?id=27128257

One of the comments there ( https://news.ycombinator.com/item?id=27138310 ) pointed out this video: https://www.youtube.com/watch?v=i2WKJtbm8yM about a project to build a cargo ship:

> This is a summary of our story so far, from building the shipyard to shipbuilding. The film follows the progress made by SAILCARGO INC. a young organisation emerging from the mangroves of Costa Rica, with the bold aim to change how the world goes about international shipping.

https://www.sailcargo.org

> Building Ceiba: 45m Square-Topsail Cargo Schooner

> We are a group of shipwrights, carpenters, business professionals and sailors. Ceiba is our effort to inspire change in the industry to which we have devoted our lives. Ceiba is a sustainably-constructed vessel that will carry cargo, 100% emission-free. When operational in 2022 she will be the world’s largest, active, clean ocean-going cargo vessel. She will elevate the existing sail cargo movement to a new level while bringing attention to the harmful and pollutive practices of the global shipping industry.

(I have no idea if it's practical, but it's wonderfully romantic and I love it!)

There are types of sails or wind power that have been investigated to reduce carbon output / efficiency of tankers but they never seem to have been deployed at scale in any sense. Basically a kite-surfing tanker.

It seems like until we get tiny compact fusion energy we'll always end up running off the cheapest oil products, as they make the most sense economically. Without any actual incentive to switch, not a single shipping company will.

LFTR: it's almost everything you want from fusion but can do now.

Scales down for the size No meltdown/overload No proliferation risk

But... artificial fuels are probably the (at least) carbon neutral path forward for shipping and aviation.

If you are interested in an account of how it was to sail tall ships I can recommend “Around Cape Horn” [0]

If you are curious about sailing tall ships. And have the means. Apply to one of these ships [1]. I have gone sailing a couple of times and it’s one of the most rewarding experiences I have had so far.

[0] https://m.youtube.com/watch?v=9tuTKhqWZso [1] https://sailtraininginternational.org/sailtraining/

German documentaries about the "Peking"s journey home to Germany from NYC [0] and then the restoration process itself [1] in Germany. Unfortunately for international viewers there are only auto-generated subtitles (and translations from those) which from a quick look are just horrendous.

[0] https://www.youtube.com/watch?v=n11HVFKO0jA

[1] https://www.youtube.com/watch?v=So609NxlTcw

You would probably enjoy the book Two Years Before the Mast by Richard Henry Dana - an account of working on a tall ship in the 1820's (Boston - Cape Horn - California). It's a personal favorite.

Here's some alternative answers:

https://en.wikipedia.org/wiki/Rotor_ship

https://en.wikipedia.org/wiki/Turbosail

https://en.wikipedia.org/wiki/Windmill_ship

It is surprisingly difficult to build a carbon neutral sailing ship …if you somehow rule out using wood, because “some of the trees might not grow back”. Utter bullshit!

The most popular class of bulk carriers (some 70%) are the mid-sized Handymax and Supramax with ~50 000 deadweight tons capacity, while employing a similar-sized crew of ~15. I honestly don't know what this clipper would need to carry to be profitable.

https://maritime-connector.com/bulk-carrier/

Ecotourists, and premium goods which advertise their cutting-edge sustainability.

Imagine the irony if a tanker ship had sails.

"Oceanbird's huge 80-meter sails reduce cargo shipping emissions by 90%"

https://newatlas.com/marine/oceanbird-wallenius-wing-sail-ca...

Hypothetically. They've not built such a beast.

It's a bit tangential, but I enjoy Moxie's (of Signal) stories relating to sailing. https://moxie.org/stories/together-two/

Tangent: thank you for the link, the whole website looks very promising! That's a tremendous collection of articles on low energy footprint. I've only skimmed through some of them but it's a joy!

You're most welcome. This one is not necessarily as good as some of the other ones.

Please let me know what websites you're thinking of! What I like with this one is the historical view and the attempt at devising new ways with simple tech.

If there can be a tax on luxury cars that are transported by ship or planes powered by fossil fuels that is reduced by wind powered shipping, I’d gather there would be innovation in this industry.

Maybe we could revisit what SkySails started https://en.wikipedia.org/wiki/SkySails

Recently: https://news.ycombinator.com/item?id=27128257

The website has a battery that indicated something was at ~83%. Apparently it is the solar-powered battery that is running the server. Cool.

Reply on news.ycombinator.com