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

solar.lowtechmagazine.com

71–80 of 90 posts

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

#71

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!)

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

#72
post #69

> 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 gen…

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.

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

#73
post #36
post #18

Earlier quoted context omitted.

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.

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

#74

Earlier quoted context omitted.

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.

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

#75
post #23
post #17

> 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 materia…

It will eventually rot and release its captured carbon.

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.

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

#76
post #63

Earlier quoted context omitted.

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.

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

#77
post #26
post #22

Earlier quoted context omitted.

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.

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

#78

Earlier quoted context omitted.

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?

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.

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

#79
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.

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

#80
post #59

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/

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.
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