Seems the retro fad continues - sail power

[alan_m]

Many pension funds rely on this - the shareholders being the general UK population.

[TimW]

[snipped]

Actually wrong in almost every respect, not to be argumentative but things aren't always how you think they are.

Sailing vessels continued to carry cargoes in great numbers and profitably, were being made new and the designs improved right up until the first world war. The thing which finished the age of sail was literally the war, and the U-Boat because they were so vulnerable to enemy action and were sunk in their hundreds.

In fact they ran for free, no fuel rerquired with a notoriously low paid crew, they could be repaired in any port in the world and there were reliable routes and times. There was plenty of low value, high volume, non-urgent cargo to be carried.

TW

[Andrew]

An amazing number of container ships come to grief every decade. The thought of these contaminating the oceans and making salvage ops *very* expensive is the reason why nuclear powered commercial shipping is a non-starter.

[Soup]

So those that are time sensitive move by air? So what is the point of worrying (over much) about the speed of ships?

[The Natural Philosopher]

No. Not if you are in business to make money.

It is perfectly possible to look at prevailing winds on sea routes and do calculations and am sure people have.

As someone else pointed out the way sailing ships sailed are not the same as today's sea lanes

A modern sailing ship would do far better to mount a wind turbine on top than sails. That would work with a wind in any direction including straight into the wind.

But *at best* a huge fuckoff wind turbine might produce 2-3MW if it didn't capsize the ship. and a big container ship needs at least 60MW.

And the wind even at sea is not always there.

In practice you would be carrying around something that mostly was simply dead weight and needless capital expense for at best a couple of percent fuel saving, and you simply *cannot* do better than that. There is a formula relating sail area and wind speed to power output that is derived not from constructional ingenuity, or from vivid imagination, but from *physical laws*.

When I attended an engineering meeting may years ago at the Prodrive rally team, on behalf of a client trying to sell them an infinitely variable gearbox design, the question was asked by the MD, Dave Richards, of his engineering director 'how much time, do we lose in gear changes, and how much time by sub-optimal gear ratios 'and the engineering guy said 'well each gear change is 60ms and we do around 500 per stage under acceleration so that 30 seconds spent coasting instead of at full power. and that would be around...0.5 seconds per stage.

And that was it, Dave Richards thanked us and said 'for what you want me to pay for that gearbox I can spend a week tyre testing and guarantee myself 2 seconds a stage'.

And that is how you win world WRC championships. Not by doing qualitative analysis, but by being brutally hard nosed about things. A top F1 racing driver might cost you 8 million and only net you 0.5 seconds a lap, but a top aero guy might only cost you 150,000 and net you the same advantage

That formula relating wind speed and sail area I don't have to hand, but it exists, its real, and even if you could get closer top it than the Betz limits, in the end the numbers don't add up to a significant increase in performance. You can get more by drag reduction making the ship a bit longer or adding a nose on it..

[The Natural Philosopher]

Owners of commercial companies do. If they don't, they go out of business

That would imply that they think there passengers give a flying f*ck about the environment. If they did they would be on a cruse liner.

[The Natural Philosopher]

Yes, that's the latest boondoggle. Instead of subsidised windfarms, subsidised umbrellas.

All 100 times more costly than just dealing with a modest rise in temperature, which (a) May not in fact happen and (b) even if it does, may be nothing to do with CO2

The ArtStudents™ are in control . No one is thinking this through in the dash for green cash.

[alan_m]

Fuel is not the only cost running a ship. There may be savings in fuel costs to be made with slower speeds but increased costs associated with running and financing the ship.

[The Natural Philosopher]

No, I dont. As I have tried to explains o many times, there is a huge metaphysical divide between those who deal with the RealWorld™ and ArtStudents™, who deal exclusively with *what people think* (or can be

*induced to believe*) is the real world.

In ArtStuident™ world, there is an infinite supply of fossil fuel which we have to stop using because it is going to set the planet on fire. I kid you not.

In the real world there is a very limited supply of *accessible* fossil fuel and we have already burned more than half of it, especially oil and gas, and most of the oil and gas does not lie under the control of Western democracies. Excluding the USA and Norway, you are buying it off religious fanatics or Vladimir Putin,

Ukraine coming to a town near you.

Or nuclear power. Your choice

[The Natural Philosopher]

Number still dont add up

Best output from biomass is about 0.2W/sq meter

You cannot support today's global populations without energy not derived from 'today's' sunlight.

And any attempt to do it will result in far far more climate change than burning last years billion years of sunlight, as fossil fuels.

Get yourself a thermal camera and look at the temperature of a solar farm a city, a field full of wheat and a forest and see which ones heat the planets surface the most...

[The Natural Philosopher]

Precisely. This Left Wing 'myth that 'they' these mystical shareholders are not in fact YOU with a pension ...

[The Natural Philosopher]

That is predicated on the false simple minded ArtStudent™assumption that 'green' technology results in less fossil fuel burned. The CO2 levels at Mauna Loa utterly refute that.

Actually petrochemical feedstocks is not a big issue. We cant grow enough carbon organic compounds for energy but we sure can to make synthetic hydrocarbons for e.g. plastic and synthetic rubbers.

No. The problem is not even energy. There is more uranium floating around than we could possibly ever need for thousands of years. The problem is in fact transport fuel.

The likelihood is that synthetic hydrocarbon fuel will be so expensive that it will completely change the transport dynamics of today. Working from home will be the norm.

Last 5 mile electric trucks from the railway hub will deliver your online goods. If you want to go to Australia an electric short range taxi will take you to an electric train station which will take you to Southampton docks where a nuclear powered ship will take a week to get to Sydney.

The world will de globalise and devolve from an international elite to smaller fiefdoms.

And anyone with the fossil fuel to run a mechanised war will invade their neighbours.

[Colin Bignell]

That seems to epitomise most of the university projects I know about, innovative solutions to a problem that turn out either not to be commercially viable or are impractical in the field.

The drone that prompted my query is definitely innovative, but I can't see it being anything other than, at best, a niche market. The stealth aspect might appeal for military aircraft, but I don't see it being adopted by civil aviation, if only because of the cost of having the technology certified for use by the aviation authorities. The war in Ukraine shows that the need is for cheap drones that can be manufactured in bulk, which that does not appear to be.

[The Natural Philosopher]

Why would they contaminate the oceans any more than they are already?

Reactors are sealed. The sea has 4billion tonnes of uranium in it already, of which at least 2% is U235.

And oceans are f****ng big places.

By the time the pressure vessels had rotted through, what was inside would be harmless and low radioactivity and anyway sitting at the bottom of the biggest spent fuel tank you can imagine.

[The Natural Philosopher]

That is what I said, if you look at the cost accounting of freight transport, there is a sweet spot where your asset is moving enough freight annually to repay the interest on the loan, but not enough to overly increase fuel costs.

ArtStudents never think about money, because they live their whole lives being paid by grants from taxpayers.

[RJH]

Good for you - most didn't have that luxury.

Sometimes, sometimes, you would do well to think beyond the market. TEQs:

[RJH]

And many are coming round to divesting from fossil fuels.

Investing in and benefitting from something isn't intrinsically right. IOW - do the ends justify the means?

[Tim Lamb]

How about nuclear powered tugs? Cut the towline if the cargo bursts into flames.

[TimW]

Not so. The wind in the ocean is remarkably dependable. TW

[TimW]

The doldrums actually a particular lattitude between a belt of relaibly East wind and a belt of reliably West wind which are prone to calm and need to be crossed in a North - South passage, illustrating how constant and dependable ocean weather is. TW