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I was wondering what it would take to replace a current container ship by a sail boat, like a clipper. Apparently, each container ship has more or less a 100 ti

by seren 7y ago

I was wondering what it would take to replace a current container ship by a sail boat, like a clipper. Apparently, each container ship has more or less a 100 times the tonnage of a clipper. Independently of the speed of the ships, the cost of the crews would probably kill the idea, except for goods with a very high margin, but there must a fuel price (including carbon tax) where this should become economically viable again.

willvarfar 7y ago
There are lots of experiments and even production ships with sails these days. Google for "sails on container ships" for lots of nice pictures and articles. The sails don't look like historic sails - they are often rotors that look like cylinders. Maersk's Pelican, for example, is supposed to get 10% from its rotor sails. Tangent: why do wind turbines look so conventional, with their propellers? There is a lot online about vertical axis wind turbines etc, but I've never seen one.
- joaomacp 7y ago
  Article from 2015: https://www.wired.com/2015/05/future-wind-turbines-no-blades https://www.wired.com/2015/05/future-wind-turbines-no-blades I guess they're still not feasible for some reason.
- TaylorAlexander 7y ago
  I forget the details but vertical axis wind turbines are always less efficient than horizontal axis turbines. Off the top of my head I can't recall if the reason is that vertical axis turbines always have half of the rotor turning against the wind, but there is a basic reason I believe can be found on wikipedia.
  - willvarfar 7y ago
    https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine says > research at Caltech has also shown that a carefully designed wind farm using VAWTs can have an output power ten times that of a HAWT wind farm of the same size etc The cups on the normal wind speed sensor have less drag into the wind. It would be easy to imagine a VAWT where a computer knew the wind direction and feathered the blades on the back sweep etc?
    - TaylorAlexander 7y ago
      Interesting. I think I was wrong that the disadvantages I had seen before were easily found on Wikipedia. But I do see this quora post with bad things to say about VAWTs: https://www.quora.com/What-are-the-pros-and-cons-of-vertical-axis-wind-turbines https://www.quora.com/What-are-the-pros-and-cons-of-vertical...
- bilbo0s 7y ago
  The problem is exhaust and the waste pollutants in it. If you switch to sails for a 10% improvement, wouldn't that mean you are still producing 90% of the waste pollutants and pumping it into the environment?
- r00fus 7y ago
  > Tangent: why do wind turbines look so conventional, with their propellers? There is a lot online about vertical axis wind turbines etc, but I've never seen one. Not sure if they still exist but east of SF on 580 (Altamonte pass?) I think there are still some.
  - scrumbledober 7y ago
    I don't think there are any left that are visible from the freeway. I remember them being touted as a newer more efficient design, I wonder why they have been replaced by more traditional designs?
pnako 7y ago
But maybe you don't need crews, and ships that big. Perhaps it would be viable to operate a semi-autonomous fleet of dozens or hundreds of medium-sized wind-powered ships; it's possible that wind turbines + battery + electric engine would be better than sail. A trimaran could accommodate wind turbines and a certain number of standard containers that would also act as ballast. COLREGs probably prevent unmanned ships, but regulations can evolve if you can convince that there is an actual safety improvement (the ships could be coupled with satellites and flying drones to increase visibility/radar/tracking awareness).
- Gwypaas 7y ago
  The biggest question in regards to windpowered vessels is always "how do you deliver on time?". With logistics turning more to just in time deliveries to reduce warehousing a ship turning up a day late is not acceptable, which creates knock off issues with slot times in harbours not aligning and you either pay higher prices for later scheduling or having to pay for an unused slot. This is not even taking into consideration the power requirements of chilled containers. I'm all for making ships more efficient using wind, every percent is a win but the shipping industry is never going back to it as the main propulsion method. The electric side is really interesting, it is viable in some cases today. I've done some napkin math about outfitting a traditional sailing ship I volunteer on with batteries from Corvus mentioned in another comment and it's completely viable today. Unless going for huge system needing a complete overhaul of the inside layout we would still need a generator for range above about 5-6 hours but that could run on carbon neutral HVO diesel.
  - MayeulC 7y ago
    Is there any resources regarding wind turbines as electricity generators for propulsion? I imagine this could work pretty well, maybe even with headwind (?), owning to the different densities (and inertia) of water and air, as well as their relative velocities. Yet everyone I've told this to called me nuts, likening this to perpetual motion, etc. I'd likely go with hydrogen storage for boats, especially if the system is reversible (though I've read it can be quite difficult to filter input water).
jonasvp 7y ago
Check out https://fairtransport.eu/ https://fairtransport.eu/, they've been doing that for over 10 years. The story of Captain Gustaf Erikson is also instructive in that regard: https://postcarbonlogistics.org/2019/06/28/captain-eriksons-equation/ https://postcarbonlogistics.org/2019/06/28/captain-eriksons-...

by seren 7y ago

willvarfar 7y ago

There are lots of experiments and even production ships with sails these days. Google for "sails on container ships" for lots of nice pictures and articles. The sails don't look like historic sails - they are often rotors that look like cylinders. Maersk's Pelican, for example, is supposed to get 10% from its rotor sails. Tangent: why do wind turbines look so conventional, with their propellers? There is a lot online about vertical axis wind turbines etc, but I've never seen one.

joaomacp 7y ago
Article from 2015: https://www.wired.com/2015/05/future-wind-turbines-no-blades https://www.wired.com/2015/05/future-wind-turbines-no-blades I guess they're still not feasible for some reason.
TaylorAlexander 7y ago
I forget the details but vertical axis wind turbines are always less efficient than horizontal axis turbines. Off the top of my head I can't recall if the reason is that vertical axis turbines always have half of the rotor turning against the wind, but there is a basic reason I believe can be found on wikipedia.
- willvarfar 7y ago
  https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine says > research at Caltech has also shown that a carefully designed wind farm using VAWTs can have an output power ten times that of a HAWT wind farm of the same size etc The cups on the normal wind speed sensor have less drag into the wind. It would be easy to imagine a VAWT where a computer knew the wind direction and feathered the blades on the back sweep etc?
  - TaylorAlexander 7y ago
    Interesting. I think I was wrong that the disadvantages I had seen before were easily found on Wikipedia. But I do see this quora post with bad things to say about VAWTs: https://www.quora.com/What-are-the-pros-and-cons-of-vertical-axis-wind-turbines https://www.quora.com/What-are-the-pros-and-cons-of-vertical...
bilbo0s 7y ago
The problem is exhaust and the waste pollutants in it. If you switch to sails for a 10% improvement, wouldn't that mean you are still producing 90% of the waste pollutants and pumping it into the environment?
r00fus 7y ago
> Tangent: why do wind turbines look so conventional, with their propellers? There is a lot online about vertical axis wind turbines etc, but I've never seen one. Not sure if they still exist but east of SF on 580 (Altamonte pass?) I think there are still some.
- scrumbledober 7y ago
  I don't think there are any left that are visible from the freeway. I remember them being touted as a newer more efficient design, I wonder why they have been replaced by more traditional designs?

pnako 7y ago

But maybe you don't need crews, and ships that big. Perhaps it would be viable to operate a semi-autonomous fleet of dozens or hundreds of medium-sized wind-powered ships; it's possible that wind turbines + battery + electric engine would be better than sail. A trimaran could accommodate wind turbines and a certain number of standard containers that would also act as ballast. COLREGs probably prevent unmanned ships, but regulations can evolve if you can convince that there is an actual safety improvement (the ships could be coupled with satellites and flying drones to increase visibility/radar/tracking awareness).

Gwypaas 7y ago
The biggest question in regards to windpowered vessels is always "how do you deliver on time?". With logistics turning more to just in time deliveries to reduce warehousing a ship turning up a day late is not acceptable, which creates knock off issues with slot times in harbours not aligning and you either pay higher prices for later scheduling or having to pay for an unused slot. This is not even taking into consideration the power requirements of chilled containers. I'm all for making ships more efficient using wind, every percent is a win but the shipping industry is never going back to it as the main propulsion method. The electric side is really interesting, it is viable in some cases today. I've done some napkin math about outfitting a traditional sailing ship I volunteer on with batteries from Corvus mentioned in another comment and it's completely viable today. Unless going for huge system needing a complete overhaul of the inside layout we would still need a generator for range above about 5-6 hours but that could run on carbon neutral HVO diesel.
- MayeulC 7y ago
  Is there any resources regarding wind turbines as electricity generators for propulsion? I imagine this could work pretty well, maybe even with headwind (?), owning to the different densities (and inertia) of water and air, as well as their relative velocities. Yet everyone I've told this to called me nuts, likening this to perpetual motion, etc. I'd likely go with hydrogen storage for boats, especially if the system is reversible (though I've read it can be quite difficult to filter input water).

jonasvp 7y ago

Check out https://fairtransport.eu/ https://fairtransport.eu/, they've been doing that for over 10 years. The story of Captain Gustaf Erikson is also instructive in that regard: https://postcarbonlogistics.org/2019/06/28/captain-eriksons-equation/ https://postcarbonlogistics.org/2019/06/28/captain-eriksons-...