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Old 06 August 2004, 14:45   #21
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Erm...

Rupert Bear,

I didn't say that they were unwelcome. I just thought that the marketing 'spin' was funny!! And illustrating the point about the size of them.

Mind you, if you ever find yourself on the prom in Blackpool, looking out to sea is most definately the best view...(even with the turbines when they arrive...)

Dylan...
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Old 06 August 2004, 16:10   #22
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to the point

We are drifting off the point here, we need next generation fuels for outboards, and inboards, diesel/petrol

we need to be running these prototypes now to see what works, what needs changing etc etc
Electrical generation with alternative sources wont help us, unless the fuel is saved for cars/boats petrol/diesel motors
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Old 06 August 2004, 17:01   #23
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Quote:
Originally Posted by gavin
We are drifting off the point here, we need next generation fuels for outboards, and inboards, diesel/petrol

we need to be running these prototypes now to see what works, what needs changing etc etc
Electrical generation with alternative sources wont help us, unless the fuel is saved for cars/boats petrol/diesel motors

Yes already available - hydrogen - why ditch 100yrs of ic engine design mucking around with fuel cells etc?
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Old 06 August 2004, 20:49   #24
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I would be very wary about Hydrogen as a gas. When mixed with oxygen at concentrations above 4% it is highly explosive.
I would need a LOT of convincing before going out with what is basically a mobile bomb
It is far more dangerous than petrol!
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Old 06 August 2004, 21:27   #25
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Quote:
Originally Posted by Rupert Bear
I would be very wary about Hydrogen as a gas. When mixed with oxygen at concentrations above 4% it is highly explosive.
I would need a LOT of convincing before going out with what is basically a mobile bomb
It is far more dangerous than petrol!

Is it really? Have you seen the results of a fuel/air bomb? They use petrol!

How is it any worse than LPG as used in numerous vehicles?

Or the butane they now use as a propellant in aerosols?
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Old 06 August 2004, 21:40   #26
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Experiments were carried out in the 70's using Hydrogen as a breathing gas by Comex. They found that if Hydrogen was mixed with oygen at a percentage above 4% the risk of a spontaneous explosion even without an ignition source was extremely high. The outcome of these experiments was the adoption of helium instead despite the scarcity and cost of it.
Petrol is only flammable in vapour form and is pretty safe even at 21% oxygen concentration unless ignited. It does have a low point of igntion but won't spontaneously explode! The experiments found that there was even a significant risk of a diver breathing hydox spontaneously exploding and if a gas can be ignited inside a wet human then I am not keen in carting it around in a fuel tank beside a battery and a warm outboard

AFAIK fuel/air bombs are "fueled" by a variety of methods-kerosene, ethylene oxide or explosive slurry, not petrol.
Anybody know for sure?
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Old 06 August 2004, 21:41   #27
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I'm with codfish on this fer sure. And so are Ford.
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Old 06 August 2004, 22:19   #28
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Quote:
Originally Posted by Rupert Bear

AFAIK fuel/air bombs are "fueled" by a variety of methods-kerosene, ethylene oxide or explosive slurry, not petrol.
Anybody know for sure?
Almost any hydrocarbon fuel can be used - even flower could be used if needed - or sawdust etc. it is way too complex a subject to discuss here!

Obviously some things are more effective than others - Kerosene is preffered because it is safer to handle than petrol and more widely used as a military fuel.

FAE bombs aren't really that reliable becuase they need ideal conditions - a high wind speed can seriously disrupt their performance.
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Old 06 August 2004, 22:26   #29
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Quote:
Originally Posted by Rupert Bear
Experiments were carried out in the 70's using Hydrogen as a breathing gas by Comex. They found that if Hydrogen was mixed with oygen at a percentage above 4% the risk of a spontaneous explosion even without an ignition source was extremely high. The outcome of these experiments was the adoption of helium instead despite the scarcity and cost of it.
Petrol is only flammable in vapour form and is pretty safe even at 21% oxygen concentration unless ignited. It does have a low point of igntion but won't spontaneously explode! The experiments found that there was even a significant risk of a diver breathing hydox spontaneously exploding and if a gas can be ignited inside a wet human then I am not keen in carting it around in a fuel tank beside a battery and a warm outboard
Butane has a Lower Flammable (Explosive) Limit (LFL/LEL) of 1.8% Propane 2.1% Hydrogen as you quite rightly stated - 4%

Guess what petrol is - 1.2%!!!!

http://www.delphian.com/chc.htm

Many people use propane and butane daily
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Old 06 August 2004, 23:53   #30
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I think my point was taken the wrong way.
Hydrogen when mixed with oxygen concentrations above 4% is highly explosive not 4% hydrogen mixed with oxygen. (Although this is also fairly flammable)
Most flammable gases and most particles in small enough sizes when mixed with atmospheric oxygen are extremely explosive, flour has been known to be a particular hazard in mills for yonks.
How did this argument start anyway? Hydrogen isn't even a particularly good fuel, it may be "clean" but its calorific value is considerably less than petrol and it isn't a very practical fuel for carting about in boats. If I had to take a guess on what would be used in the future it would still be internal combustion but with fuels derived from agricultural methods and refined. ie rapeseed and sunflower and suchlike.
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Old 07 August 2004, 01:39   #31
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Agree there - RAPE may be the answer!!!
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Old 07 August 2004, 12:55   #32
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I am sure sexually molesting an outboard must but be against the law?
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Old 09 August 2004, 07:28   #33
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We have outboards at Barrus that run on LPG, and a multi fuel engine that runs on Diesel/Petrol and Avcat (Helicopter fuel)!.
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Old 09 August 2004, 07:54   #34
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Quote:
Originally Posted by Rupert Bear
However there are now plans to set up windfarms of 200-400 huge turbines on some exposed areas.
Forgive my ignorance but don't wind farms need to be located in exposed areas - so they get some wind?!!

Andy Beach
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Old 09 August 2004, 08:05   #35
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Quote:
Originally Posted by codprawn
Yes already available - hydrogen - why ditch 100yrs of ic engine design mucking around with fuel cells etc?
The current generation of IC engines are only about 25% efficient - that is to say they only convert about 1/4 of the stored energy in the fuel into useable power - the rest is lost mainly as heat. Now that's OK when you've got an energy rich fuel source such as petroleum, but any other form of fuel has much less energy, hence the poor efficiency becomes more of an an issue.



Quote:
Originally Posted by Andy Stevens
Also they have developed cars that run on water yet the oil companies spend millions on buying the patents to keep oil in demand!
Fuel Cell vehicles (which run on hydrogen, not water – water is the by-product of the process) are at least 10 years away from a production-feasible vehicle. Those that are running today are still very much research-oriented, as there remain many technical issues to solve to ensure they will be reliable for your average consumer on a mass-production basis to make them reasonably priced. GM is rumoured to have spent $1billion to get their current fleet of (I think four) fuel cell vehicles on the road.

And that is to say nothing of the huge investment in infrastructure that will be necessary to put a hydrogen filling station on every corner - that is if people will accept this once the scaremongerers amongst us start ranting about the prospect of a 'H'-Bomb type explosion in a residential neighbourhood!! Hydrogen is very hard to contain (being a very small molecule) and, unlike petrol vapour or LPG/CNG, it is lighter than air and disperses very quickly. Yes - it is possible to generate an explosive mix but very difficult to maintain this for any significant length of time (especially on a boat!).


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Old 09 August 2004, 09:30   #36
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Quote:
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Forgive my ignorance but don't wind farms need to be located in exposed areas - so they get some wind?!!

Andy Beach
(Birmingham-based Scottish Power Consumer!)
One of the best if not the best areas for constant windspeeds AND wave generated power is NW Scotland. The main objection locally is that folk don't want huge windfarms despoiling the very reason that they live here in the first place.
There would be more of an argument if Scotland wasn't already a net exporter of power in the first place. There are enough glens flooded for hydro station here without chucking up hundreds of wind turbines as well.
Wind turbines are not even a particularly good way of generating power anyway, fairly inefficient and only being built in numbers now because of tax breaks etc.
If folk are serious about getting clean sources of power then they have to be based on water technologies to get the density for proper power generation and availability. The only real alternative is Fusion and the jury is still out on whether that will ever be practicable.
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Old 09 August 2004, 09:35   #37
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Isn't there an experimental offshore sub-sea water turbine somewhere off the UK coastline?
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Old 09 August 2004, 10:03   #38
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There is a shore based wave generator on Islay, there have also been failed experiments with surface moorings off Cape Wrath. Not aware of subsurface ones as yet but they have been talked about for a long time.
The main reasons against them at the moment is the horrendous maintenance costs and the fact that the grid would need to be extended out to sea.
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Old 09 August 2004, 10:18   #39
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I was out in Malaysia a few years ago doing some research with Uni. We spent a few days at the National Palm Oil Institute where they had a Merc C class running on a mixture of palm oil and diesel. It was about a 20 bhp drop in performance and the car stank like KFC all the time. It was mixed at about a 50% ratio and actually increased the durability of the engine cause of the lubrication properties of the stuff! I think a lower mixture rate removes the smell to below noticable levels.

A lot of people don't realise that in europe most diesel sold at PFS has a minimum of 5% bio derived products included in it so the UK is lagging behind.

Just before I sign off, please realise that an offshore wind farm is;
a) not very efficient,
b) a risk to shipping,
c) difficult to maintain,
d) requires foundations up to ten times more substantial than shore based plants. (Damage to seabed)
e) over 200 would be needed to provide the same Mw output as a nuclear fission power station.

Fission is the way forward but unfortunately it is expensive to build, maintain and run. Mind you is the better kit on your boat the cheapest in the shops?

You get what you pay for!

They do have inherent dangers but most things in this world have risks! The storage of the waste remains an issue but the amount produced in comparison to the amount that escapes up chimineys is minute.

Chris
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Old 09 August 2004, 11:45   #40
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Wate is not minute from a nuclear power station.
The popular conception of waste is the high level stuff. This is relativley small beer compared to the low level and medium level waste that is generated, this runs to tons and tons per station per year.
Nuclear power (and the bombs set off in the past) are gradually raising background radiation levels locally and globally meaning more cancers and other problems.
One point which is argued about is safe levels. There is no such thing as a "safe" dose of radiation. Every increase over background raises the risks for all sorts of health problems. the difference between most risks and radiation is that you have no choice, whether you take the risk is being decided for you by others.
The waste repository that is going to be needed eventually is going to cause all sorts of problems. I am waiting to see just where they try and put it.
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