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the power of the wind

For millennia mankind has found ways to harness the wind to help move goods and people around the waters of the world. There are lots of opinions as to who started this but it seems to have been such a good idea that lots of cultures developed it independently to suit their local circumstances, available technology and weather.

Junk rigs in the East Asia, lateen rigs in the Indian Ocean and northern Africa, square rigs in northern Europe are each a direct response to the circumstances. If the wind is nearly always from one direction as is common in the tropics you need to be able to sail well to windward and may compromise down wind efficiency, hence the triangular sail with a rigid luff. If the wind varies in direction as in northern Europe you can carry a simpler square rig, good from reach to run but pretty rubbish when sailing to windward.


The technology of rope and fabrics also had a significant impact. The junk rig has lots of lines and small panels suitable for lower strength fabrics. The European square rig has large panels and high load corners needing lower stretch stronger fabrics and ropes.


Changing sail area to respond to the varying strengths of the wind was also critical factor. In areas with consistent wind strengths and for short voyages this can be done before departing but with highly variable winds and longer passages this needs to be done 'on the run'.

Reefing can be difficult if not impossible once the building wind has filled the large un-furled sail so larger vessels evolved with multiple sails that could be furled one by one, by hand!

Gradually the high labour costs and unpredictability of wind powered vessels lost out to the efficiencies and improved reliability of motor powered shipping. Sail powered vessels became limited, mostly to leisure use. The recent development of very high strength lightweight polymers has allowed the evolution of large, very high efficiency rigs on modern yachts. With the addition of powered sail handling this allows short handed sailing and vessels that can accommodate a wide range of wind speeds and directions.


Contemporary pressures to reduce carbon emissions are leading to a re-evaluation of wind power as the most fruitful was to decarbonise shipping. We know a lot more about how wind can be harnessed and have multiple options available. Each has its advocates, some arguing from short term economic or pragmatic positions, some seem more driven by idealistic nostalgia for a bygone era, and yet others seem to be upscaling their small scale hobby sailing to solve a large scale commercial problem.


To be fair all new developments start with a broad divergence and gradually converge on the optimum solution. This convergence has historically been slow allowing supply chains, operator skills and infrastructure to keep pace. We do not have the luxury of time so it's everyone for themselves. Let's hope the solutions have the desired effect of reducing CO2 emissions.














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