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this post was submitted on 17 Mar 2024
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Hundreds of years of innovation in water travel, and we come back to a sail. Granted, a metal one, but still a fucking sail.
Hard to beat the efficiency of just having energy delivered to you for free...
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!
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
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.
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.
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
0.006%
This is the correct calculation (although the 200k figure is wrong)
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%.
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