Propane conversion

[Cap'n_Half-hitch]

Re: Propane conversion

Now I'm interested. How much do you calculate the whole conversion will cost you?

 

[madurodave]

Re: Propane conversion

and look into the 50cpg alternative fuel tax credit!

Done right and with training, you can install a 500 or 1000 gallon tank at your home/business/whatever, install a pump and fill your own tanks from this bulk tank.

 

[hungupthespikes]

Re: Propane conversion

Wouldn't a H2 system be a better option?

 

[QC]

Re: Propane conversion

NO! ^^^^^ Will discuss/debate anytime

Hydrogen, the fuel of the future, and it always will be.

 

[skargo]

Re: Propane conversion

So if it will always be the fuel of the future, we will never benefit from it?

 

[Aviator5]

Re: Propane conversion

So if it will always be the fuel of the future, we will never benefit from it?

Some people do benefit from it now. Those who sell drawings and ready made HHO generators on the web.

 

[45Auto]

Re: Propane conversion

NO! ^^^^^ Will discuss/debate anytime

Hydrogen, the fuel of the future, and it always will be.

Ok, I'll bite!

I work with hydrogen as a fuel every day! We've been using hydrogen as a primary fuel for over 50 years. The Saturn (Apollo moon rocket) rocket 2nd stage and the Space Shuttle both use hydrogen as fuel. Hard to get anything better when you're looking for maximum performance. Last cost estimate I heard was in the neighborhood of $50,000 per pound to get something into orbit. So paying a little more (ok, ok, a LOT more!) for maximum performance to avoid having to lift extra weight MAY be worth it depending upon what you're trying to achieve.

The gauge for rating the efficiency of rocket propellants is specific impulse, stated in seconds. Specific impulse indicates how many pounds of thrust are obtained by the consumption of one pound of propellant in one second. Every fuel/oxidizer combination (gas/air, etc) is simply a chemical reaction. The amount of energy you can obtain is limited by the amount of energy you can release by breaking chemical bonds. LH2 (liquid hydrogen) as a fuel with LOX (liquid oxygen) as an oxidizer has a specific impulse of 381 seconds. About the only thing higher is LH2 and liquid flourine at 400 seconds, but it's hypergolic (spontaneously combusts) and is some real nasty stuff. Every other combination of fuels and oxidizers is generally in the range of high 200's for specific impulse. So LH2/LOX is about 33% better in performance.

I don't think there's any question that hydrogen as a fuel is here to stay in the rocket industry (big $$$$$). Now if we want to get more specific and talk about the boating or automotive fields (which I knew you were talking about, QC ), I would agree that the cost/benefit ratio heads in the wrong direction!

As a side note, I was extremely disappointed with how quiet my big block was with the thru-hulls on it. You could barely hear it across the lake (Lake Pontchartrain, about 35 miles across at the narrowest) and it only disturbed people within a couple of hundred yards. So I installed a killer stereo system to play recordings of rocket motors, now I can bother people miles away!

Pic below is this year's high school robot team behind the Saturn 5 (moon rocket) lower stage on display at Michoud Assembly Facility in New Orleans, where I work. The kid in the middle is sitting on the edge of one of the nozzles. You can imagine what it costs to feed something like this!

 

[Fireman431]

Re: Propane conversion

Maybe someone that deals with fire fighting could chime in here but I always thought that the best course of action for a propane fire was to let it burn. And that trying to shut valvles could result in fire being drawn back into the tank. Is this true? How effective would someone be at controling a fire from a propane source on a boat with only a fire extinguisher?

The main reason expanding gases are let to burn is the possible detonation of the tanks that they are in. This is known as a BLEVE [blev-ee] (boiling liquid expanding vapor expolsion). This is a rapid and violent explosion of the tank that the LPG/CNG resides in. There is no warning of when it happens and usually nothing left after it does. There would be absolutely nothing a person with a fire extinguisher would do except put themselves in harms way. The positive point is that it will only burn to the waterline.

Shutting off the valve usually isn't done either mainly because that would allow the tank to continue to build pressure under the heat. Too much pressure = BLEVE. If there's so much pressure that the pressure relief valve activated (if it works), leaving the valve open is the best way to release pressure. When a valve is shut off, I really can see any possible way that a fire would be able to make it's way back into the tank. The offgassing simply wouldn't allow it.

BLEVE Video (Big Loud Explosion. Very Exciting)
http://www.youtube.com/watch?v=_Tr3iZz_ugA

 

[Aviator5]

Re: Propane conversion

You can imagine what it costs to feed something like this!

That is exactly why it will always be the fuel of the future

 

[QC]

Re: Propane conversion

Now if we want to get more specific and talk about the boating or automotive fields (which I knew you were talking about, QC ), I would agree that the cost/benefit ratio heads in the wrong direction!!

Nice, stealthy hijack sir . . .

As a side note, I was extremely disappointed with how quiet my big block was with the thru-hulls on it. You could barely hear it across the lake (Lake Pontchartrain, about 35 miles across at the narrowest) and it only disturbed people within a couple of hundred yards. So I installed a killer stereo system to play recordings of rocket motors, now I can bother people miles away!

Well you may not be on topic, but at least you're topical . . .

 

[smokeonthewater]

Re: Propane conversion

so far my propane torch has never exploded from releasing the trigger..... even if "the fire" somehow made it into the tank it would go out as there is no oxygen in there....


ya know there IS a reasonably cost effective fuel out there that is readily available and most boats run reasonably well on it......


gasoline.... real easy conversion too

 

[bhammer]

Re: Propane conversion

I think it has been said... LNG is not flamable. Dealing with the cryogenic temps in a boat would be difficult at best. LNG is methane which is lighter than air and if I remember, it has to be in a concentration of 5-15% to be flamable.

 

[kfouryou]

Re: Propane conversion

sorry to hyjack, has anyone ever considered natural gas?.

 

[Boatist]

Re: Propane conversion

My Dad's neighbor converted his tow vehicle to Propane about 15 years back.
He tows a 25 foor SkipJack. He took boat to the ocean where he comerical fishes Salmon and launched with no problem.

When it came time to retreive the boat he could not get enough power to pull the boat up the ramp.
He had to have help to get the boat up the ramp.
This was the same ramp he had used for years without problems.
So he took the truck back to the place that did the conversion and explained they need to give it more power.
They told him it will never have more than 80 percent of the power of Gasoline.
He had spent a lot of money to convert so he was not Happy.
Then he decided to sell the truck and found out can not sell in California so must be converted back.
He ended up junking the truck that was only about 5 years old.
The cost to convert back was more than the truck was worth.

 

[ltjag101]

Re: Propane conversion

dont see what everyone is all up in a hissy about i wonder what they cook with on cruise ships and dont cabin cruisers have alcy stoves what happens if there is a greese fire just saying if done right and all safety precautions taken is easy to fill on water and is cost efective for whom ever wants to do it do it and then tell who ever said it was either not possible or not worth it why it was after you do it

but like i said do it safe

 

[skargo]

Re: Propane conversion

My Dad's neighbor converted his tow vehicle to Propane about 15 years back.
He tows a 25 foor SkipJack. He took boat to the ocean where he comerical fishes Salmon and launched with no problem.

When it came time to retreive the boat he could not get enough power to pull the boat up the ramp.
He had to have help to get the boat up the ramp.
This was the same ramp he had used for years without problems.
So he took the truck back to the place that did the conversion and explained they need to give it more power.
They told him it will never have more than 80 percent of the power of Gasoline.
He had spent a lot of money to convert so he was not Happy.
Then he decided to sell the truck and found out can not sell in California so must be converted back.
He ended up junking the truck that was only about 5 years old.
The cost to convert back was more than the truck was worth.

His tow vehicle must have been either a POS or the conversion was screwed up.

 

[Boatist]

Re: Propane conversion

His tow vehicle must have been either a POS or the conversion was screwed up.

His truck was a nice ford long bed Pick up.
It ran great but just did no have as much power as before.
It runs great and clean but porpane just does not have as much power as gas.

it about 7 percent less power.

 

[QC]

Re: Propane conversion

sorry to hyjack, has anyone ever considered natural gas?.

Yeah, go back tho the beginning of the thread.

I sell LNG and CNG conversions for heavy trucks. Have been doing so worldwide for 15 years. I can categorically tell you that a CNG conversion for a pleasure craft is borderline ridiculous, and an LNG conversion even worse. There are so many factors to consider, and despite the fact that Methane (CNG & LNG) is safer than propane and definitely safer than gasoline, most of the other factors stack up against it. But let's talk about the biggest benefit of natural gas . . . the money.

The only reason to consider these things is economics. Being "green" is a very gray discussion which I would gladly get into if we can do it civilly, but I am guessing that most here consider these things for the economics. Imagine fuel savings of a dollar per equivalent gallon (that means to equalize the money for the same energy and we could spend a week discussing equivalent gallons too if anyone would like to ). And let's say that the CNG conversion was $10,000 (I can back this up). It would take 10,000 gallons to get your money back. OK, let's get half of that back from the Gov't (I know of no programs for pleasurecraft, but I am keeping an open mind), so that means you could get your dough back in 5,000 gallons . . . Anybody want to guess how long it takes for a typical pleasure boater to burn 5,000 gallons?

 

[skargo]

Re: Propane conversion

His truck was a nice ford long bed Pick up.
It ran great but just did no have as much power as before.
It runs great and clean but porpane just does not have as much power as gas.

it about 7 percent less power.

Your earlier post said he only had 80% max. That is NOT my findings at all, having converted a vehicle I owned and drove. He had something going on other than the propane conversion if he couldn't pull a boat up a ramp

 

[QC]

Re: Propane conversion

I would tend to agree with that ^^^^^ The only reason that propane or natural gas conversion systems drop max power in an Otto cycle engine (spark plugs and a throttle) is that the gaseous fuels are less dense than gasoline and displace air in the cylinder, which lowers the max amount of fuel that can be burnt which lowers power.

If you want to discuss Octane and the role it plays we can, but that does not change the fact that these fuels are less dense at ambient temps and pressures (intake manifold). If you want to discuss boosted air, whether a supercharger or a turbocharger, that is yet another discussion. Annnd, if we want to talk propane or nat gas injection into diesel engines, that is yet another discussion and happens to be the one I know the most about. When these technologies and fuels get mixed together it becomes a very messy, confusing and inaccurate discussion. Extremely complicated despite the fact that I also find it a lot of fun . . .