https://www.theguardian.com/environment/2017/mar/14/spinning-sail-reboot-cut-fuel-make-ocean-tankers-greener

So it has become commercially viable to start using (partially) wind powered trading ships again. The steam punks were right all along!

I couldn’t get my head around those rotor sails but this video helped a lot

[video]https://m.youtube.com/watch?v=8kVuKAqy_2k[/video]

Powered by dropping basketballs off a dam. Or something.

Prefer the Skysails approach tbh- the tow kites- but these are cool too.

Various systems have been tried over the last 30 years and none of them have been successful.

I remember this being shown on TV technology shows decades ago. It was tried but it didn’t work very well.

Wiki says: “Despite having completed trouble free crossings of the North Sea and Atlantic the power consumed by spinning 15m tall drums was vastly disproportionate to the propulsive effect when compared with conventional screws (propellers)”

See: https://en.wikipedia.org/wiki/Rotor_ship

Someone using he magnus effect to achieve lift on a model aeroplane

[video]https://www.youtube.com/watch?v=acXvl-8xrBM[/video]

Wiki says: “Despite having completed trouble free crossings of the North Sea and Atlantic the power consumed by spinning 15m tall drums was vastly disproportionate to the propulsive effect when compared with conventional screws (propellers)”

Good point, I saw that, the impression I got was that the new ship is making it work by using the rotor sails to supplement a propeller, rather than replace it..

I’m old enough to remember Walker Wing Sail 😳

globalti – Member

I remember this being shown on TV technology shows decades ago. It was tried but it didn’t work very well.

Sure, but history is full of ideas that were tried, didn’t work very well, then were tried again with newer tech and processes or better understanding of the principles.

Sure, but history is full of ideas that were tried, didn’t work very well, then were tried again with newer tech and processes or better understanding of the principles.

The shipping industry is ruthless. The margins are tiny, particularly at the moment. It’s incredibly cheap to ship a container from China to Europe.

This system is designed to assist the main engines and reduce overall fuel consumption.

There will be a small reduction in cargo capacity, it will have maintenance and training costs and a significant installation cost. If the numbers don’t add up in the favour of the ship then the trial will be dropped. Margins and revenues are so low, that even giants like Maersk can’t afford to have any fat.

A German wind turbine company have a ship that uses this technology to save fuel, seen it in a port somewhere, I seem to remember it’s called the E ship 1 owned by Enercon?

Scotsman here you go E Ship 1

^^ that looks upside down 😀

Can someone explain how that works better than sails which need no power (other than winches)?

Surely if it works efficiently, then aeroplanes would use it rather than wings (sails).

And surely those things would be a massive drag going upwind?

Apparently even the old attempts could sail at up to 30 degrees into the wind, these might have pushed that further (and there’ll be a further area even further into the wind where they produce power, just not enough to sail the ship, which would offset or cancel wind drag). Skysails (kites) can only sail with the wind and traditional masted sails can only sail obliquely into the wind

(I hadn’t noticed that Skysails went bankrupt, wonder if anything’s going to survive from that… It seemed like a sound idea that, pretty low investment/negative impact on the ship.)

thisisnotaspoon – Member

Surely if it works efficiently, then aeroplanes would use it rather than wings (sails).

Efficient doesn’t mean effective, a plane needs to produce enough lift to fly- there’s no point in something that produces insufficient lift, very efficiently.