Gas ( LPG ) powered boat ?

[oldboot]

All the issues with gas on boats must have been dealt with in QLD because all the brisbane ferry fleet run on gas CNG admitredly but still gas.
This includes all the cross river ferries and the city cats.
OH these are all diesel motors too.

I dont think it is an unreasonable expectation at all

as for the venting....that has to be delt with in vehicles that have tanks inside like 90% of taxis...... so I don't think it is an issue

gas on a ststionary type motor I don't see as a problem at all....well tried.

gas on an outboard would be another thing all together......all the fuel systems are different from cars so injection platesor carbies and stuff would have to be spec made.

then you have to get heat from somewhere to do the liquid to gass conversion..... thats not easy with an outboard
then there is the issue of flexible hoses to the motor..... where do you put the exchannger....... very messy.

also when the talk about cars running cold in the cooling system that is still way hotter than a typical outboard cooing system.

and if it is a two stroke......what do you do with the oil

yeh stationary motor........ a doddle.......outboard....hard very hard

cheers

[tin can marlin]

I think we will see it our life time maybe 25 years away.

[TimiBoy]

With long tanks under the floor, how much flex in the hull are you expecting? You'd need to be very wary of that not translating to flex in the tanks.

You probably thought of that, but I thought I'd mention it...

Fascinating thread!

Tim

[marco]

Phil,

the LPG in the cyl effectively burns off and no harm is done to anyone -

miko1 , i think you have forgotten about the " bleve " effect which makes your statement rather dangerous .

google bleve for some cool youtube stuff

boiling liquid expanding vapour explosion

http://en.wikipedia.org/wiki/BLEVE

http://www.youtube.com/watch?v=8FdXTq9LXOY

[dogsbody]

Should have no problems with LPG power boat if regulations in the relevant states allow it.

Been happening in the UK for quite some time.

http://marinegasconversions.com/conopt.aspx


Dave.

[marco]

another consideration for the long term economics of the project would be the corrosion aspect and in particular the storage tanks . replacement of these every 2 or 3 years may put a dent in the budget .

i think oldboots comment about the comparison with moving outboards to stationary inboards is valid as well , there are flexible hoses on the market that could do the job but i would think would require hose testing every year or so which adds more exspense .

[BM]

I have been considering putting LPG on my 175 Suzuki. I was going to give Jon Eadie a ring on it. Maybe Suzuki would like to help as well. Tuning the set up might be difficult. How do we dyno the outboard? Does anyone have thoughts on this or info to share. Russ

Presently, LPG setups are being tested in China for Suzuki outboards. A mate of mine is over there. He is not involved in whats occuring but he is a boating enthusiast hence him knowing about it.

Outboard dyno's are available.

[BM]

Sydney has water taxis that have been running LPG for some years now. Several other countries do also.

Chers

[Bonus]

I was going to have 2 above floor tanks. My boat has plenty of room, so it should carry 2- 45Kg bottles. These hold 90 litres each,so 180 litres all up. This gives a range of 150 nautical miles approx. It would be good for the environment and the wallet. I wonder if the government would give us the $2000 rebate? HaHa no chance. Lets be positive with these ideas as it would very benificial.

[mik01]

miko1 , i think you have forgotten about the " bleve " effect which makes your statement rather dangerous .

google bleve for some cool youtube stuff

boiling liquid expanding vapour explosion

http://en.wikipedia.org/wiki/BLEVE

Marco, this is precisely what the valve is designed to prevent - it 'vents' and releases the pressure in the vessel (cyl) - the gas shoots out and burns off.

of course, a bleve can occur where the air surrounding the cyl is so hot that the pressure in the cyl rises too quickly that even the venting cannot release sufficient pressure.

which is why my suggestion was to don your jacket and jump overboard rather than attempt a fire fight. let it burn out, and if it does and the boat still floats then you're safe

ps - you've taken my comments totally out of perspective. I have seen a few lpg cylinders on fire and personally turned the valves off (controlled tests) - a bleve is a major rupture caused by excessive heat - usually a fire that cannot be controlled.

respect LPG and it is a very safe fuel - I reckon it gets a bad rap due to general 'ignorance' - doesn't help when blokes blow themselves up through dodgy practices

[mik01]

Should have no problems with LPG power boat if regulations in the relevant states allow it.

Been happening in the UK for quite some time.

http://marinegasconversions.com/conopt.aspx


Dave.

yep - however this is vastly different a setup to what Phil was seeking.
this is an externally mounted cyl of a limited capacity (i guess about 60-80 litres)

long range tanks underfloor is what Phil was enquiring about - vastly different scenario.

I don't know what the setup is on the ferries, however once again, different scenario to the one Phil seeks.

any LPG setup on a 6m rig would have limited range (perhaps max 80 litres) - the cost benefits vs cost to setup, maintain and loss of range are probably all reasons why its not a more mainstream fuel solution today

[marco]

Marco, this is precisely what the valve is designed to prevent - it 'vents' and releases the pressure in the vessel (cyl) - the gas shoots out and burns off.

of course, a bleve can occur where the air surrounding the cyl is so hot that the pressure in the cyl rises too quickly that even the venting cannot release sufficient pressure.

which is why my suggestion was to don your jacket and jump overboard rather than attempt a fire fight. let it burn out, and if it does and the boat still floats then you're safe

ps - you've taken my comments totally out of perspective. I have seen a few lpg cylinders on fire and personally turned the valves off (controlled tests) - a bleve is a major rupture caused by excessive heat - usually a fire that cannot be controlled.

respect LPG and it is a very safe fuel - I reckon it gets a bad rap due to general 'ignorance' - doesn't help when blokes blow themselves up through dodgy practices

hi mik ,
with all due respect i havent taken your comments out of perpective at all , your comment was open to interpretation and i needed to point the danger out .
i have had numerous years dealing with lpg in bulk quanities and i have had all the required training and the one thing you do in the case of fire is run like all f%^$ . that comes from the fire trainers and i have seen a molten mess that was once a bulk road tanker .

you are correct about the vent off valve but if it is at the point where it is ignited then it is too late to hang around with any certanity that the tank will not rupture therefore i disagree with your staement about no danger .
i also agree with having respect for the stuff but dont be fooled , it is much mre dangerous than petrol .

[oldboot]

I don't think it is reasonable to say that LPG is much more dangerous than petrol.

Dangerous in a different way, possibly.

More dangerous in some ways, or more dangerous in some situations most probably.

It's like discussion what is more dangerous a bus or a train.



Any sort of established fuel fire on board a small boat makes a swimm look to be a good proposition.

The packaging and installation practices for gas certainly address most of the associated risks, and it could be argued that the risks for gass are better managed than the risks for petrol in many typical installtions.

Anyway.............what sort of event aboard a small boat is going to cause a gas container to be " a significant danger"? I would argue that the event that would cause a gass container to vent would present sufficient danger to abandon ship on its own. That same or similar event applied to a typical petrol tank would also present a large and overwhelming danger.

The single most probable danger from both gass and liquid fuels abboard a boat is leakage, with the associated risk of explosion and fire.

gass will redily disipate in open air where liquid fuels will sit in puddles and run where it wants, soaking soft materials. Thus a liquid fuel provides gaseous fumes for reddy ignition a a resovour of fuel for continued combustion.

It could therefore argue that all liquid fuels are more dangerous than gasses on open boats.

What realy matters is that approprite consideration is given to the installtion of whatever fuel systemis employed. Because gass fitting is a licenced and regulated occupation it is reasonable to expect that a gas instaltion could easily be safer than a liquid fuel one.

how many underfloor petrol tanks are incorrectly vented, how many people have tried to fill their fuel tanks thru their rod holders, how many petroll tanks are inspected regularly by a qualified and licenced person.

I think the use of LPG and CNG on rectreational boats is overdue, and the dangers compared to liquid fuels are similar.

cheers

[mik01]

hi mik ,
with all due respect i havent taken your comments out of perpective at all , your comment was open to interpretation and i needed to point the danger out .
i have had numerous years dealing with lpg in bulk quanities and i have had all the required training and the one thing you do in the case of fire is run like all f%^$ . that comes from the fire trainers and i have seen a molten mess that was once a bulk road tanker .

you are correct about the vent off valve but if it is at the point where it is ignited then it is too late to hang around with any certanity that the tank will not rupture therefore i disagree with your staement about no danger .
i also agree with having respect for the stuff but dont be fooled , it is much mre dangerous than petrol .

Marco - without getting into a measuring contest, I am very knowledgeable in relation to gases, particularly LPG.

we are arguing apples and oranges here...
your point relates to bulk installations, where we are discussing portable cylinders possibly only around 200L max.

of course, in the situation of a bulk (multi tonne) cyl being engulfed in flames - you run. there is simply no way to cool the cylinder down, or 'drown' the fire with a water deluge.

having said that, the Bleve effect is not immediate - any suggestion of this is a simplistic stereotype.

a rupture of any kind is caused by heat weakening the metal of the cyl vs the pressure of the contents inside. the science of it is that it takes time for the heat to build to a sufficient level for a rupture to occur - dependent of course on the ferocity of the fire surrounding it (ie bushfire). in this case you would not be hanging around at all (as Oldboot says)

i strongly disagree with your comment that once ignited, it is 'too late' - as if rupture is immediate. the science does not support that theory.

I have personally seen lpg cylinders next to a (timber) house survive the whole house burning down - the valves vented and the gas burnt off. also, I have personally turned off 9kg cyls that were on fire.
The Fireys at Lytton regularly use ignited lpg cylinders in old cars as training for the real thing - interesting to hear from them on how many rupture.

I am not advocating there is 'no danger', as that would be irresponsible. in the scenario we are discussing, as I have stated in every post, jump overboard and swim away is the only thing you can do.

Having said all of this, I would not have lpg on my boat in an underfloor solution.
Even though I do still support my comment that it is safer than petrol - if it was so volatile and dangerous that simply igniting a leak causes a rupture we would not have access to it in the public domain.

[marco]

well e will have to agree to disagree , i have seen the end result of even 4.5kg bottles rupturing in the rear of a car .

the danger with lpg is more to do with it being a compressed gas and mik , your comments about the firies at lytton are great but they are trained about this stuff . most of the public are not .
remember you said "the LPG in the cyl effectively burns off and no harm is done to anyone"

that comment is dangerous to someone who is not trained about lpg .

and we havent even got onto the subject of cold burns .