Seems the retro fad continues - sail power

[Soup]

True, but for every "Doldrums" there is a "Roaring forties".

[Soup]

Yeah but early steam engines were 'pants' (shit has been used too often, to my mind, in this thread already). But even rubbishy steam engines were 'better' than pure sailing ships which is why, as far as I am concerned, dual drive systems will come to the fore . Engines when docking, in "The Doldrums" or facing a wind. sail (or rather a suitable variation) wence running with the wind .

[SteveW]

Indeed. Long distance racing yachts use weather routing, going out of their way and increasing the distance they have to travel, in exchange for more speed and so arriving sooner.

[Rod Speed]

Nowhere to fold them down to with a container ship and nowhere to have the masts when the wind is useful either.

Even that cruise ship that does have extra sails doesnt in fact use them much at all because the sails arent useful very often. There is a doco on it in the ship doco series.

[Rod Speed]

The trouble is that the roaring fourtys arent on the trade routes anymore.

[Rod Speed]

Not a chance now that the vast bulk of freight moves in containers now and sail just wont work on a container vessel.

Too slow to be useful now.

[Rod Speed]

Just not feasible for container ships and tankers. The roaring fourtys are much too far away from the trade routes now due to the modern canals and even when the suez is too risky to use, its f****ng long way with f*ck all wind in the right direction even when Good Hope has to be used.

[alan_m]

A necessity when they had no other means of propulsion but best avoided for calmer waters when there is an alternative.

[alan_m]

It's more of a marketing gimmick on a cruise ship with sails.

[alan_m]

So ships with early rubbish engines were better (for trade) than the sailing ships that they made obsolete so why would sailing ships now replace the modern cargo ship with much better engines? Hybrid ships of

150 years ago with both sails and (rubbish) engines also disappeared and this wouldn't have happened if there was some major benefit in keeping the sails.

[Chris Hogg]

Quite, but the objective today isn't necessarily economy, but the (misguided) objective of reducing CO2 output at almost any cost.

It'll be oars next!

[The Natural Philosopher]

the only slight reason for return to auxiliary sails is that modern electronic controls mean you don't need the huge crew numbers, and modern weather satellites and computers mean you could take advantage of what winds there actually are.

But like most 'let's go back 200 years and try again' ideas the game probably ain't worth the candle.

Non engineers always think that somehow they can make sailing ships, airships, windmills and the like function in the modern world despite the fact that (most of) the reasons they were superseded are still there.

The classic example of evolution that *does* work is the trend in airliners for larger and larger turbofans, to get more low speed thrust and reduce fuel burn at subsonic speeds, and the use of even wider wingspans with tapering wing tips to reduce tip drag - even if they have to turn the tips up to fit the airports. And the use of new materials like carbon fibre and honeycomb strictures to reduce weight without compromising strength. This all pays for itself in terms of lower fuel per tonne mile.

But in ships, the huge quantum leap would be to go nuclear. The fuel is so cheap it wouldn't feature in cost calculations at all. Probably the most profitable way to run a nuclear ship is flat out all the time. More tonne miles per year to offset the interest on the build cost.

[alan_m]

I do wonder about the reporting by the companies promoting these ideas.

In this case are the savings in fuel use (reduction in CO2) only for the limited time when the sails can be used or are they for the whole of a typical round trip journey?

It's much like the output from wind generators. The figures usually quoted the are peak output under ideal operating conditions whereas real world data over a long period tells us that 30% of this figures may be achievable, ignoring for shorter periods the figure may fall to 0%.

[RJH]

CO2 is often a proxy and abbreviation for anthropogenic climate change. CO2 isn't the only climatic consequence of fossil fuels, but it is the one that is most often mentioned. And it's often used a pejorative - as you've done here - to somehow state that there's no link between CO2 and climate.

That's that, and while you obviously believe what you write, it'd be clearer I think if you simply state that fossil fuel consumption has no impact on climate. If you do it's more refutable - but more 'honest'.

And consuming fossil fuels have other, not directly climate-related, problems

- air/land/sea pollution, extraction, waste, unequal accumulation of wealth. And the whole geopolitics of the stuff. All good reasons to think about scaling back, and not making pithy remarks.

[The Natural Philosopher]

No. The objective today isn't necessarily economy, but the (cynical) objective of *pretending* to reduce CO2 output at almost *no* cost.

People who can do sums are well aware that most people cannot, so a

*story* about 'saving carbon' works just as well as real carbon savings, and at far lower cost.

And even people who can do sums cant necessarily *think*.

Year ago our buyer spent weeks negotiating 10% off the price of all resistors used in our product. The product cost fell by 5p!

In the middle of the unit was a huge f*ck off toroidal transformer costing £25!! one percent off that would have made *far* more difference.

No: people are lazy, innumerate, and not especially bright, but they still all think that their propaganda derived opinions are as good as anyone elses, because Blair told them they were.

The ArtStudents™ are in charge. Almost any idiocy is possible.

[Chris Hogg]

The 'Savannah' was expensive ($46.9 million in the late 1950's, including a $28.3 million nuclear reactor and fuel core, according to Wiki), but would the build cost be that expensive today? With nuclear powered marine engines in submarines, and RR supposedly developing land-based SMR's, the cost of equipping bulk carriers and large container ships with nuclear engines shouldn't be excessive.

The biggest problem would be acceptance. IIRC 'Savannah' was banned by many maritime countries from entering their ports.

[Tim Streater]

I always laugh when I see this, being the contradiction in terms that it is.

[Jethro_uk]

The roaring forties was a parrot owned my my aunt who I live with.

[Jethro_uk]

[Colin Bignell]

I wonder how many university projects make it into the real world.