7 ms·

Wind-powered ships are making a comeback

92 points by Osiris30 8y ago

mattlondon 8y ago
Some more info on the actual tech: https://www.norsepower.com/technology https://www.norsepower.com/technology and https://www.norsepower.com/rotor-sail-solution https://www.norsepower.com/rotor-sail-solution Obligatory wikipedia entry: https://en.wikipedia.org/wiki/Rotor_ship https://en.wikipedia.org/wiki/Rotor_ship
tzs 8y ago
Good demonstration of the Magnus effect: https://www.youtube.com/watch?v=QtP_bh2lMXc https://www.youtube.com/watch?v=QtP_bh2lMXc
- cgag 8y ago
  This is the video they reference at the end that elaborates and shows off the use in ships, as well as some planes that have spinning cylinders instead of wings: https://www.youtube.com/watch?v=2OSrvzNW9FE https://www.youtube.com/watch?v=2OSrvzNW9FE
Apocryphon 8y ago
It seems prudent to invest in some low-tech solutions, just in case resource-intensive high-tech solutions fail us in the long run.
- masklinn 8y ago
  Rotor sails aren't really low-tech though, the original pre-WWII attempts failed because the sails were too heavy and the engines (to rotate the "sails") not efficient enough, so the rotor sails were a net energy loss (aka using the engines to power regular screws was more efficient even in best-case scenarios). The new attempts (since the mid-augths) use advanced modern material science to build the sails, no way you can replicate that in a low-tech non-industrial context. It's way more complex than an ICE (and in fact requires one to power the rotors themselves).
newnewpdro 8y ago
These green-washed headlines are getting absurd. Wind-powered suggests there's no fossil fuel based propulsion, when these rotors are driven by the same propulsion system as the ship's propellors: diesel.
- masklinn 8y ago
  Wind-powered suggests that motile power is provided by the wind, which is the case here. Surely a sailboat with electrically controlled surfaces is still wind-powered?
  - dwighttk 8y ago
    There is still a diesel engine in the loop, which if turned off makes the ship not move. These are like electric hybrid cars which are sometimes thought* of more valuable than increased efficiency of burning gas (which is all they boil down to) *at least I used to think that. Maybe I'm the only one.
    - masklinn 8y ago
      > There is still a diesel engine in the loop, which if turned off makes the ship not move. So it is with my sailboat example? > These are like electric hybrid cars which are sometimes thought* of more valuable than increased efficiency of burning gas (which is all they boil down to) Most hybrid cars are plug-in, you can charge the battery directly and use mixed-electric mode or even exclusively electric mode for short distances.
      - dwighttk 8y ago
        Most sailboats operate fine if the engine is off. It may be that plugin hybrids are more numerous now, but for a very long time most hybrids did not have the plug in option.
    - deleted 8y ago
      [deleted]
  - 8y ago
escherplex 8y ago
This idea was already broached at HN in Maersk installed 100-foot-tall rotating sails on one of its tankers https://news.ycombinator.com/item?id=17885284 https://news.ycombinator.com/item?id=17885284 But a question arises as to practicality of this configuration in extreme weather at sea. That's a lot of wind swept area aloft abovedeck. In extreme weather conditions with rolling seas, an elongated cargo vessel such as a tanker will be subject to sagging (central portion suspended in space between two wave crests). Given strong head or tail wind force imposed on tall rotor shafts it would seem that extra torque would be imparted on the central section increasing the liklihood of hull failure under full cargo load.
- strainer 8y ago
  I would guess that the bending and twisting pressures of swelling and crashing water, rather dwarfs the potential forces the cylinders can drag through air in a storm, especially while they are not spinning. And I'd guess they would be engineered to break off, before harming the hull if that could be a threat.
- gehsty 8y ago
  Fairly sure this is an naval architecture problem a company of Maersk scale would be able to solve. There may be additional strengthening installed whilst the sails are installed. Seems like a ‘use more steel’ type problem.
  - escherplex 8y ago
    Yeah, presumably so. But most articles of this sort tend to be more like one-sided sales pitches. Personally, I'd fall over if I saw an article which adopted a Kantian 'thesis' 'antithesis' ergo suggested 'synthesis' approach.
    - pasabagi 8y ago
      Hegelian, you mean. Kantian argument would be pretty boring, as it's typically exhaustive.
mrfusion 8y ago
Would wind turbines make more sense? It seems like they’d be catching a larger cross section of wind.
- strainer 8y ago
  I believe its possible, with stability being the big problem. Self stabilized, floating, tethered and large scale wind turbines are already being built[1] - so its something to look out for in the future. [1]https://www.equinor.com/en/news/hywindscotland.html https://www.equinor.com/en/news/hywindscotland.html
mrfusion 8y ago
On the flip side could these replace conventional wind turbines to generate electricity?
- gpm 8y ago
  Hard to imagine how. They use wind to generate a linear force. We like to have rotational forces to feed generators.
  - mrfusion 8y ago
    We have lots of ways to turn linear force into rotational. My car engine would like to have a word with you. Off the top of my head. Hook it up to a crankshaft. On the push stroke turn the motor on and capture the wind. On the pull stroke turn off the spinning and let it return to vertical.
- carapace 8y ago
  Magenn Power, Inc. (now defunct maybe?) was building tethered aerial generators. Just search for "Magenn" with two 'n's.
bcl 8y ago
Current location and some before and after pictures - https://www.marinetraffic.com/en/ais/details/ships/shipid:730851/mmsi:565686000/vessel:MAERSK%20PELICAN https://www.marinetraffic.com/en/ais/details/ships/shipid:73...
tibu 8y ago
And again, they try to be cheaper by manufacturing in China. When do we realize that this is a trap we created for ourselves...?
- kvartz 8y ago
  Why wouldnt we want to manufacture everything for less?
  - dredmorbius 8y ago
    Supply-chain control. Technical knowledge. Innovation capacity.
slycke 8y ago
A different but interesting concept: https://www.skysails.info/skysails-marine/skysails-antrieb-fuer-frachtschiffe/vorteile/ https://www.skysails.info/skysails-marine/skysails-antrieb-f...
WalterBright 8y ago
I recall back in the 80's someone made a freighter with a computer controlled sail on it. It was written up in Popular Science (?) as the future of freighters and tankers. Never heard about it again.
- jandrese 8y ago
  IIRC it turned out to be impractical and was shelved after the test runs.
qume 8y ago
I really want this to be a thing, but my rough calculations given the total cross section area of the sail and the average wind conditions on shipping routes come out to as close to nil as makes any difference for ships these size. I posted a very rough calculation on the last HN post about this and got downvoted for some reason. I guess everyone else wants this to be a thing so much they are happy to set aside physics through sheer force of will. HN people and the investors / instigators of this project. This is one time I'm desperately wanting to find out I'm completely wrong. My last post in a nutshell - these things are order of magnitude the same size as the sail on my own sail boat. Forget about the type of sail. Even if 100% of that wind energy was converted to forward motion it's going to do essentially nothing in the context of a big ship.
- danielvf 8y ago
  Do you have numbers to share? Link to your previous post? It looks like it's being installed on the Maersk Pelican - a "small" tanker. https://www.marinetraffic.com/en/ais/details/ships/shipid:730851/mmsi:565686000/imo:9319686/vessel:MAERSK_PELICAN https://www.marinetraffic.com/en/ais/details/ships/shipid:73... I think I've heard that in, general, wind gets quite stronger the higher the sail is. Is this in your calculations?
  - qume 8y ago
    No I don't, my calculations at this stage are as follows: Sail area - same as my 10 ton boat. Gets me to 7kts in a good strong wind. Boat they intend to install it on: 110000 tons! My point is that for this to have any impact at all, a massive amount of energy has to be extracted from the wind. An amount of energy that just doesn't exist in the volume of moving air they are talking about. I'm still baffled by this.
    - deleted 8y ago
      [deleted]
    - llukas 8y ago
      This is more complicated - you ignore hull speed for one. Amount of force needed to move ship through waves is non linear: https://en.wikipedia.org/wiki/Hull_speed https://en.wikipedia.org/wiki/Hull_speed
cies 8y ago
If petrol for ships was taxed like petrol for cars, this would have already been common place. Hell if petrol for planes was taxed like car-petrol they bring back zeppelins!
- dwighttk 8y ago
  oh the humanity
agumonkey 8y ago
What about populating building tops with these ?
- ansible 8y ago
  Are your buildings moving around and eating each other like that recent dystopian SF work, a la Mortal Engines?
  - agumonkey 8y ago
    It would require quite long devices to move.
danielvf 8y ago
For some actual numbers from a real freighter with four Magnus effect columns on it, check out this pdf https://www.ship-efficiency.org/onTEAM/pdf/06-STG_Ship_Efficiency_2013_100913_Paper.pdf https://www.ship-efficiency.org/onTEAM/pdf/06-STG_Ship_Effic...
your-nanny 8y ago
why use the amp link? Firefox on Android won't open
lokedhs 8y ago
The Magnus effect is pretty cool. I firs came across it when watching this video which shows how effective it is by dropping a ball from a height while spinning it. https://youtu.be/QtP_bh2lMXc https://youtu.be/QtP_bh2lMXc
yskchu 8y ago
This article is a bit lacking in the visual imagery department (that picture in the article is super old) - here's a youtube link from Norsepower (the article says they're the manufacturer): https://www.youtube.com/watch?v=FUCShEXkpL8 https://www.youtube.com/watch?v=FUCShEXkpL8
Pietertje 8y ago
Interestingly the problem tends to be economical rather than technological. A 5 years ROI would normally be sufficient to get traction. Apparently the current system of charterers is holding it back.
walrus01 8y ago
I question whether the cost of doing this in new novel naval architecture isn't excessive. You can have a green ship without installing Magnus effect rotor sails: A) install a massive ground mount photovoltaic system Or massive wind farm on land. B) use the kWh from it to crack water into pressurized tanks of hydrogen C) transport the hydrogen to the ship, store it onboard, and run it through fuel cells to drive electric azipods. This require the engineering resources for on board hydrogen tank system, fueling system and fuel cells. Less mechanically complex than massive rotor sails, and something that all of the subcomponents exist for "off the shelf". This lets you use otherwise useless, non arable land for the energy generation. Even if the electricity to hydrogen process is extremely inefficient. At a certain point if you plot the ongoing price drops for massive grid scale PV, when PV panels hit $0.20/watt, it will be economical.
- gumby 8y ago
  Hydrogen plumbing is not really a solved problem so I challenge the "less mechanically complex". Those hydrogen atoms are really small! The margin on shipping is low enough that I suspect they looked at everything they could get off the shelf before settling on this one, which I agree is complex. It will be interesting to see the long time life of these sails.
- vosper 8y ago
  > I question whether the cost of doing this in new novel naval architecture isn't excessive. You can have a green ship without installing Magnus effect rotor sails: > A) install a massive ground mount photovoltaic system > Or massive wind farm on land. > B) use the kWh from it to crack water into pressurized tanks of hydrogen Or, though it's in a different sense of "green ship": provide the power generated by the solar array / wind farm very cheaply or at-cost to offset the emissions generated by the ship. It doesn't make the ship emissions go away, but it could make something that's grid-connected become carbon neutral.
secretaryiwsa 8y ago
Very pleased to see such a debate going on over wind propulsion in commerial shipping. I am the secretary of the International windship Association (IWSA), www.wind-ship.org, we are a not-for-profit that represents over 50 technology and project members developing these systems, and Norsepower, the manufacturer of these rotorsails is one of those. There are currently 6 commercial vessels in operation using variants of the flettner rotor, E-ship 1, a new build vessel that was launch in 2009 and has operated around the world, The M/V Estraden in operation since 2014 on a regular ferry route from Rotterdam to Hull, and then 4 new vessel installations this year, the MV Afros, 64,000dwt bulker with 4 rotors, the Maersk Pelican tanker with 2, the MV Fehn Pollux and the Viking Grace ferry/crusie with single rotors. If you are interested to engage with the sector, please visit the website, join our linkedin group or request a newsletter - we will have a large number of announcments coming from the 5 wind propulsion technology solutions in the coming months too. All the best Gavin Allwright, IWSA Secretary www.wind-ship.org

92 points by Osiris30 8y ago

Some more info on the actual tech: https://www.norsepower.com/technology https://www.norsepower.com/technology and https://www.norsepower.com/rotor-sail-solution https://www.norsepower.com/rotor-sail-solution Obligatory wikipedia entry: https://en.wikipedia.org/wiki/Rotor_ship https://en.wikipedia.org/wiki/Rotor_ship

tzs 8y ago

Good demonstration of the Magnus effect: https://www.youtube.com/watch?v=QtP_bh2lMXc https://www.youtube.com/watch?v=QtP_bh2lMXc

cgag 8y ago
This is the video they reference at the end that elaborates and shows off the use in ships, as well as some planes that have spinning cylinders instead of wings: https://www.youtube.com/watch?v=2OSrvzNW9FE https://www.youtube.com/watch?v=2OSrvzNW9FE

Apocryphon 8y ago

It seems prudent to invest in some low-tech solutions, just in case resource-intensive high-tech solutions fail us in the long run.

masklinn 8y ago
Rotor sails aren't really low-tech though, the original pre-WWII attempts failed because the sails were too heavy and the engines (to rotate the "sails") not efficient enough, so the rotor sails were a net energy loss (aka using the engines to power regular screws was more efficient even in best-case scenarios). The new attempts (since the mid-augths) use advanced modern material science to build the sails, no way you can replicate that in a low-tech non-industrial context. It's way more complex than an ICE (and in fact requires one to power the rotors themselves).

newnewpdro 8y ago

These green-washed headlines are getting absurd. Wind-powered suggests there's no fossil fuel based propulsion, when these rotors are driven by the same propulsion system as the ship's propellors: diesel.

masklinn 8y ago
Wind-powered suggests that motile power is provided by the wind, which is the case here. Surely a sailboat with electrically controlled surfaces is still wind-powered?
- dwighttk 8y ago
  There is still a diesel engine in the loop, which if turned off makes the ship not move. These are like electric hybrid cars which are sometimes thought* of more valuable than increased efficiency of burning gas (which is all they boil down to) *at least I used to think that. Maybe I'm the only one.
  - masklinn 8y ago
    > There is still a diesel engine in the loop, which if turned off makes the ship not move. So it is with my sailboat example? > These are like electric hybrid cars which are sometimes thought* of more valuable than increased efficiency of burning gas (which is all they boil down to) Most hybrid cars are plug-in, you can charge the battery directly and use mixed-electric mode or even exclusively electric mode for short distances.
    - dwighttk 8y ago
      Most sailboats operate fine if the engine is off. It may be that plugin hybrids are more numerous now, but for a very long time most hybrids did not have the plug in option.
  - deleted 8y ago
    [deleted]
- 8y ago

escherplex 8y ago

This idea was already broached at HN in Maersk installed 100-foot-tall rotating sails on one of its tankers https://news.ycombinator.com/item?id=17885284 https://news.ycombinator.com/item?id=17885284 But a question arises as to practicality of this configuration in extreme weather at sea. That's a lot of wind swept area aloft abovedeck. In extreme weather conditions with rolling seas, an elongated cargo vessel such as a tanker will be subject to sagging (central portion suspended in space between two wave crests). Given strong head or tail wind force imposed on tall rotor shafts it would seem that extra torque would be imparted on the central section increasing the liklihood of hull failure under full cargo load.

strainer 8y ago
I would guess that the bending and twisting pressures of swelling and crashing water, rather dwarfs the potential forces the cylinders can drag through air in a storm, especially while they are not spinning. And I'd guess they would be engineered to break off, before harming the hull if that could be a threat.
gehsty 8y ago
Fairly sure this is an naval architecture problem a company of Maersk scale would be able to solve. There may be additional strengthening installed whilst the sails are installed. Seems like a ‘use more steel’ type problem.
- escherplex 8y ago
  Yeah, presumably so. But most articles of this sort tend to be more like one-sided sales pitches. Personally, I'd fall over if I saw an article which adopted a Kantian 'thesis' 'antithesis' ergo suggested 'synthesis' approach.
  - pasabagi 8y ago
    Hegelian, you mean. Kantian argument would be pretty boring, as it's typically exhaustive.

mrfusion 8y ago

Would wind turbines make more sense? It seems like they’d be catching a larger cross section of wind.

strainer 8y ago
I believe its possible, with stability being the big problem. Self stabilized, floating, tethered and large scale wind turbines are already being built[1] - so its something to look out for in the future. [1]https://www.equinor.com/en/news/hywindscotland.html https://www.equinor.com/en/news/hywindscotland.html

mrfusion 8y ago

On the flip side could these replace conventional wind turbines to generate electricity?

gpm 8y ago
Hard to imagine how. They use wind to generate a linear force. We like to have rotational forces to feed generators.
- mrfusion 8y ago
  We have lots of ways to turn linear force into rotational. My car engine would like to have a word with you. Off the top of my head. Hook it up to a crankshaft. On the push stroke turn the motor on and capture the wind. On the pull stroke turn off the spinning and let it return to vertical.
carapace 8y ago
Magenn Power, Inc. (now defunct maybe?) was building tethered aerial generators. Just search for "Magenn" with two 'n's.

bcl 8y ago

Current location and some before and after pictures - https://www.marinetraffic.com/en/ais/details/ships/shipid:730851/mmsi:565686000/vessel:MAERSK%20PELICAN https://www.marinetraffic.com/en/ais/details/ships/shipid:73...

tibu 8y ago

And again, they try to be cheaper by manufacturing in China. When do we realize that this is a trap we created for ourselves...?

kvartz 8y ago
Why wouldnt we want to manufacture everything for less?
- dredmorbius 8y ago
  Supply-chain control. Technical knowledge. Innovation capacity.

slycke 8y ago

A different but interesting concept: https://www.skysails.info/skysails-marine/skysails-antrieb-fuer-frachtschiffe/vorteile/ https://www.skysails.info/skysails-marine/skysails-antrieb-f...

WalterBright 8y ago

I recall back in the 80's someone made a freighter with a computer controlled sail on it. It was written up in Popular Science (?) as the future of freighters and tankers. Never heard about it again.

jandrese 8y ago
IIRC it turned out to be impractical and was shelved after the test runs.

qume 8y ago

I really want this to be a thing, but my rough calculations given the total cross section area of the sail and the average wind conditions on shipping routes come out to as close to nil as makes any difference for ships these size. I posted a very rough calculation on the last HN post about this and got downvoted for some reason. I guess everyone else wants this to be a thing so much they are happy to set aside physics through sheer force of will. HN people and the investors / instigators of this project. This is one time I'm desperately wanting to find out I'm completely wrong. My last post in a nutshell - these things are order of magnitude the same size as the sail on my own sail boat. Forget about the type of sail. Even if 100% of that wind energy was converted to forward motion it's going to do essentially nothing in the context of a big ship.

danielvf 8y ago
Do you have numbers to share? Link to your previous post? It looks like it's being installed on the Maersk Pelican - a "small" tanker. https://www.marinetraffic.com/en/ais/details/ships/shipid:730851/mmsi:565686000/imo:9319686/vessel:MAERSK_PELICAN https://www.marinetraffic.com/en/ais/details/ships/shipid:73... I think I've heard that in, general, wind gets quite stronger the higher the sail is. Is this in your calculations?
- qume 8y ago
  No I don't, my calculations at this stage are as follows: Sail area - same as my 10 ton boat. Gets me to 7kts in a good strong wind. Boat they intend to install it on: 110000 tons! My point is that for this to have any impact at all, a massive amount of energy has to be extracted from the wind. An amount of energy that just doesn't exist in the volume of moving air they are talking about. I'm still baffled by this.
  - deleted 8y ago
    [deleted]
  - llukas 8y ago
    This is more complicated - you ignore hull speed for one. Amount of force needed to move ship through waves is non linear: https://en.wikipedia.org/wiki/Hull_speed https://en.wikipedia.org/wiki/Hull_speed

cies 8y ago

If petrol for ships was taxed like petrol for cars, this would have already been common place. Hell if petrol for planes was taxed like car-petrol they bring back zeppelins!

dwighttk 8y ago
oh the humanity

agumonkey 8y ago

What about populating building tops with these ?

ansible 8y ago
Are your buildings moving around and eating each other like that recent dystopian SF work, a la Mortal Engines?
- agumonkey 8y ago
  It would require quite long devices to move.

danielvf 8y ago

For some actual numbers from a real freighter with four Magnus effect columns on it, check out this pdf https://www.ship-efficiency.org/onTEAM/pdf/06-STG_Ship_Efficiency_2013_100913_Paper.pdf https://www.ship-efficiency.org/onTEAM/pdf/06-STG_Ship_Effic...

your-nanny 8y ago

why use the amp link? Firefox on Android won't open

lokedhs 8y ago

The Magnus effect is pretty cool. I firs came across it when watching this video which shows how effective it is by dropping a ball from a height while spinning it. https://youtu.be/QtP_bh2lMXc https://youtu.be/QtP_bh2lMXc

yskchu 8y ago

This article is a bit lacking in the visual imagery department (that picture in the article is super old) - here's a youtube link from Norsepower (the article says they're the manufacturer): https://www.youtube.com/watch?v=FUCShEXkpL8 https://www.youtube.com/watch?v=FUCShEXkpL8

Pietertje 8y ago

Interestingly the problem tends to be economical rather than technological. A 5 years ROI would normally be sufficient to get traction. Apparently the current system of charterers is holding it back.

walrus01 8y ago

I question whether the cost of doing this in new novel naval architecture isn't excessive. You can have a green ship without installing Magnus effect rotor sails: A) install a massive ground mount photovoltaic system Or massive wind farm on land. B) use the kWh from it to crack water into pressurized tanks of hydrogen C) transport the hydrogen to the ship, store it onboard, and run it through fuel cells to drive electric azipods. This require the engineering resources for on board hydrogen tank system, fueling system and fuel cells. Less mechanically complex than massive rotor sails, and something that all of the subcomponents exist for "off the shelf". This lets you use otherwise useless, non arable land for the energy generation. Even if the electricity to hydrogen process is extremely inefficient. At a certain point if you plot the ongoing price drops for massive grid scale PV, when PV panels hit $0.20/watt, it will be economical.

gumby 8y ago
Hydrogen plumbing is not really a solved problem so I challenge the "less mechanically complex". Those hydrogen atoms are really small! The margin on shipping is low enough that I suspect they looked at everything they could get off the shelf before settling on this one, which I agree is complex. It will be interesting to see the long time life of these sails.
vosper 8y ago
> I question whether the cost of doing this in new novel naval architecture isn't excessive. You can have a green ship without installing Magnus effect rotor sails: > A) install a massive ground mount photovoltaic system > Or massive wind farm on land. > B) use the kWh from it to crack water into pressurized tanks of hydrogen Or, though it's in a different sense of "green ship": provide the power generated by the solar array / wind farm very cheaply or at-cost to offset the emissions generated by the ship. It doesn't make the ship emissions go away, but it could make something that's grid-connected become carbon neutral.

secretaryiwsa 8y ago

Very pleased to see such a debate going on over wind propulsion in commerial shipping. I am the secretary of the International windship Association (IWSA), www.wind-ship.org, we are a not-for-profit that represents over 50 technology and project members developing these systems, and Norsepower, the manufacturer of these rotorsails is one of those. There are currently 6 commercial vessels in operation using variants of the flettner rotor, E-ship 1, a new build vessel that was launch in 2009 and has operated around the world, The M/V Estraden in operation since 2014 on a regular ferry route from Rotterdam to Hull, and then 4 new vessel installations this year, the MV Afros, 64,000dwt bulker with 4 rotors, the Maersk Pelican tanker with 2, the MV Fehn Pollux and the Viking Grace ferry/crusie with single rotors. If you are interested to engage with the sector, please visit the website, join our linkedin group or request a newsletter - we will have a large number of announcments coming from the 5 wind propulsion technology solutions in the coming months too. All the best Gavin Allwright, IWSA Secretary www.wind-ship.org