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

solar.lowtechmagazine.com

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

#81

Post by meristohm »

> 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?

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

#82

Post by noir_lord »

outworlder wrote: post #66
samatman wrote: post #45

> 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…

> 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 anoth…

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!"

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

#83

Post by evgen »

meristohm wrote: post #81

> 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,…

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.

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

#84

Post by citrin_ru »

socialdemocrat wrote: post #78
abfan1127 wrote: post #34

Earlier quoted context omitted.

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.

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.

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

#85

Post by kiliantics »

socialdemocrat wrote: post #75
faichai wrote: post #23

Earlier quoted context omitted.

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.

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.

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

#86

Post by andromeduck »

samatman wrote: post #45

> 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…

> 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.

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

#88

Post by sealeck »

meristohm wrote: post #81

> 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,…

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

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

#89

Post by sealeck »

edeion wrote: post #56

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.

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

#90

Post by edeion »

sealeck wrote: post #89
edeion wrote: post #56

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.
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