this post was submitted on 17 Mar 2024
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Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world.  About 1C of total warming.  Second chart:  about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability.  Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases.  About 0.5C of cooling with large error bars from SO2.

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[–] [email protected] 130 points 7 months ago (4 children)

Hundreds of years of innovation in water travel, and we come back to a sail. Granted, a metal one, but still a fucking sail.

[–] [email protected] 71 points 7 months ago (1 children)

Hard to beat the efficiency of just having energy delivered to you for free...

[–] [email protected] 40 points 7 months ago

Those damned sails stealing the earth's winds for free.

Global warming you know why it's happening? Because the sails are all stopping the global winds! No winds to blow the heat away and it all warms up! BAN SAILS TODAY to MAKE AMERICA GREAT AGAIN!

[–] [email protected] 56 points 7 months ago* (last edited 7 months ago)

The scale of a sail needed to propel a giant cargo ship is really quite a bit different from what you might imagine on an old frigate, aka a "pirate ship." Making a sail that large out of traditional materials is not feasible, and would require a ton of people to operate it. One of these monstrosities is staffed by probably less than 20 people, and labor is expensive, so this sort of computer operated sail can be both feasible and cost effective, whereas old school type sails were not

[–] [email protected] 37 points 7 months ago

What's old is new again. Time is a flat circle. But really, technology has a good habit of compounding gains. One new idea applied to a hundred old ones really gets innovation running hot.

[–] [email protected] 10 points 7 months ago (2 children)

There's a reason they quit, though. It's slow and doesn't let you go in every direction. The midline area of earth has winds that move mostly towards west, while the north and south portions blow mostly east.

For those curious, these sails save 12 tons per day. The average cargo ship uses around 200,000 tons per day, so around 6% better fuel economy.

[–] [email protected] 17 points 7 months ago* (last edited 7 months ago) (1 children)

Thanks for putting it into relation to daily use. 200,000 is not realistic though. Just had a google and found this source citing up to 400 metric Tons/day

https://maritimepage.com/fuel-consumption-how-much-fuel-cargo-ship-use/

12 is 0.6% of 200,000 btw

[–] [email protected] 9 points 7 months ago (1 children)
[–] [email protected] 4 points 7 months ago

This is the correct calculation (although the 200k figure is wrong)

[–] [email protected] 7 points 7 months ago (1 children)

The 12 tons are a best case and they represent 37% of this ship's fuel consumption, that would be ~32.5 tons a day, on average it saved 3.3 tons, ~10%.

[–] [email protected] -1 points 7 months ago

Which makes the break-even point for such wingsails, which cost one hell of alot more than a few tonnes of fuel did .. rather far-away/long-term, doesn't it?


There was also a system using huge parachute-kite things, on carbon-nanotube-ropes, fired up into the sky with rocket-assist, and the things could apparently pull the ship, quite effectively...

.. the service-subscription the ship was supposed to pay-for gave them the optimal route for fuel-savings vs time-to-get-there..

here, it was sorta like this, but the kite-sail looked different, and I'm pretty-sure they were saying something about nanotube cable for the kite, and it wasn't just a concept, it was actually-working...

https://marinersgalaxy.com/giant-kite-pulls-ship-across-atlantic/


I seem to remember that at the beginning of covid, some shipping companies just shortened the bulbs on their hulls, to optimize for a slower cruising-speed, and saved money that way..

again, where's the break-even on it

[–] [email protected] 68 points 7 months ago

saved an average of 3.3 tons of fuel each day. And in optimal weather conditions... reduced fuel consumption by over 12 tons a day. According to Cargill’s math, that’s an average of 14 percent less greenhouse gas emissions from the ship. On its best days, Pyxis Ocean could cut that down by 37 percent.

[–] [email protected] 39 points 7 months ago (1 children)

This is fascinating. I got questions.

What's the ROI? Is it a no-brainer to install these things for the cost savings? If not, and if they prove out, governments should look at making them mandatory and providing partial subsidies. Or, maybe an easy loan to jump start adoption?

This video answered some more questions. They do indeed fold down for rough weather and clearance and appear to rotate 360°.

I'm assuming they're computer controlled for max efficiency?

https://www.youtube.com/watch?v=AB7cLkSVmJA

Not seeing any downsides here.

[–] [email protected] 11 points 7 months ago (2 children)

The biggest downside I could see is the sails getting in the way of cranes.

[–] [email protected] 16 points 7 months ago (1 children)

According to that video, they fold out of the way. I'm not sure if they currently fold on the real ones. The article mentions:

the 125-feet of height added by WindWings could potentially complicate docking in many locations. According to Jan Dieleman, president of Cargill’s Ocean Transportation business, they’re already working to address such issues.

Which seems to imply they don't. Their solution of modifying ports to accommodate the sails might mean the folding aspect wasn't viable?

[–] [email protected] 6 points 7 months ago

Not sure about this one example but working in the industry and following the development of wing sails the ones I've seen will fold one way or the other. This example in the article is probably a prototype or even experimental implementation to test the efficency.

Examples of folding sails in development: https://www.theoceanbird.com/oceanbird-wing-560/

https://terntank.com/2023/02/sail-into-the-future/

[–] [email protected] 2 points 7 months ago

You wouldn't need them in port so make them easy to disconnect or compact into a smaller space.

[–] [email protected] 13 points 7 months ago (1 children)

Looks like this only works for bulk haulage and wouldn’t be compatible with intermodal freight (shipping containers)

[–] [email protected] 11 points 7 months ago (1 children)

Why wouldn't it? Those sails are 37m tall. I found stacked containes to be at max stacked up to 25m.

[–] [email protected] 2 points 7 months ago

At a guess, because the 25m of containers only leave you with 12m of sail sticking out of the top.

You can’t make the sail higher, as you’d just end up rolling the ship.

[–] [email protected] -3 points 7 months ago (3 children)

seems like they could make that a solar panel and a flat battery at the same time as being a sail

[–] [email protected] 19 points 7 months ago

Making it a battery would likely add a lot of weight while taking away structural integrity.

[–] [email protected] 5 points 7 months ago (1 children)

Solar yes battery would be a problem from a weight stand point. That much weight that far out could cause acrwy things.

In the other hand hard say of the solar would be that useful for the cost to install since there is no guarantee it would be facing the sun correctly. Creating a deck cover of solar though could be useful.

[–] [email protected] 2 points 7 months ago

I think these new fangled bendable solar panels might work. The bog thing to know is that cargo ships already are diesel-electric, so you can just immediately consume any generated electricity (reducing load on the engine and saving fuel).

[–] [email protected] 3 points 7 months ago

You want low weight for stability on a ship and batteries are heavy