LPG for vehicles

ronaldj

Senior Chief Petty Officer
Joined
Apr 1, 2013
Messages
655
I think it really depends on where you live as to the price of propane
Propane is 110 octane, pump gas is 87 octane.
In the mid-atlantic area propane is a lot cheaper
Propane is even cheaper at a marina

They do make much lighter propane 20 lb tanks than the standard bbq grill tank
They come in 10, 20 and 25 pound sizes
http://www.litecylinder.com/Portals/litecylinder/Products/specs/LC_2-12_Revised_20_lb.pdf

The other part of the equation is TCA (total cost of ownership)
If you have to store your engine at all then it is no contest between propane and gas.
Propane wins by a huge margin.
Small gas engines do not like the ethanol fuel blend and have created a new industry just to keep them clean and unclogged.
For a gas engine you also have to add the cost of fuel stabilizer ,sea foam and whatever else you use to keep the engine from clogging up.

Also at least in the lower 48, all large cities use propane to power buses and fleet vehicles
They already did the math and propane was cheaper
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

I think it really depends on where you live as to the price of propane
More about when, not where. Propane is lower in Summer. In winter it spikes. Every year. With that said, I agree, geography matters as well.

Propane is 110 octane, pump gas is 87 octane.
OK, but how does this translate into anything tangible? What does that get a typical user of propane?

In the mid-atlantic area propane is a lot cheaper
Propane is even cheaper at a marina
Remember, you must multiply Propane per "gallon" cost by 1.4 to get your comparable cost to gasoline. If Propane is $3.00 a gallon, then the equivalent cost is $4.20. If you don't do this math you are not comparing properly.

They do make much lighter propane 20 lb tanks than the standard bbq grill tank
They come in 10, 20 and 25 pound sizes
http://www.litecylinder.com/Portals/litecylinder/Products/specs/LC_2-12_Revised_20_lb.pdf
Good link, and composites definitely help the weight equation. However, they make the initial investment higher. Both need to be factored.

The other part of the equation is TCA (total cost of ownership)
Agree. And all things need to be accounted for. Initial investment, fuel savings, maintenance +/-, even convenience as you note.

Small gas engines do not like the ethanol fuel blend and have created a new industry just to keep them clean and unclogged.
This is not really accurate. Ethanol has been known to cause some gasoline deposits to come loose in older fuel systems. There is no evidence of any issues when used in newer engines, small or large, and used consistently.

Also at least in the lower 48, all large cities use propane to power buses and fleet vehicles
They already did the math and propane was cheaper
This is seriously false. There are very few operations anywhere in the US with large vehicles using Propane. As far as engine availability is concerned there is nothing commonly available above 250 horsepower. There are no Heavy Duty engines operating on Propane almost anywhere in the world. And no manufacturers offer systems. There are a few small conversion companies, but no indications of any successful penetration. Again those comments are for heavy duty.

There ARE a few companies with Medium Duty trucks running on Propane. Schwans is probably the most visible. Most others are actually in the Propane business and it explains their motivation.

Propane at one time, was the most popular alternative fuel worldwide for light duty. I am not positive if this is still true. Interestingly enough the reason Propane has been limited to medium and light duty is Octane. It just can't survive in a compression ignition engine cycle (diesel). Knock limits max power output to around 60% of diesel in these engines. The opposite is true with Otto cycle engines (spark plugs). The compression ratio can be raised, or boost increased as compared to gasoline.
 

ronaldj

Senior Chief Petty Officer
Joined
Apr 1, 2013
Messages
655
Re: How many miles per $

Re: How many miles per $

I cant speak for the west coast but on the east coast all the major transit power there buses by propane.
The utilities vehicles run propane as well as some of the larger fleet vehicles.

The gas issue may also just be a east coast thing
This is a common problem for any engine that sits a long time

What I can tell you is that if all you need is 5hp and occasional use Propane wins.
That is as compared to my honda 5hp
The honda is about 10lbs heavier.
From my experience with my honda 2000's
The honda will probably last longer
(now we have another item for TCOA- Longevity
The current propane engines are only 2years old)

I have no experience with the 9.9hp engine yet.
 
Last edited:

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

I cant speak for the west coast but on the east coast all the major transit power there buses by propane.
The utilities vehicles run propane as well as some of the larger fleet vehicles.
You must be referring to CNG or LNG. There are currently no Heavy-Duty manufacturers delivering any LPG products in the US. Zero. No engines either. There just aren't. Again, there are some medium duty options, but still rare. No Heavy-Duty LP products. Never have been. You used to be able to buy a 190 hp 5.9 B series Cummins on LPG. That's about it for larger vehicles, and that doesn't get you into to Transit, Refuse and especially not heavy-duty truck.
 

ronaldj

Senior Chief Petty Officer
Joined
Apr 1, 2013
Messages
655
Re: How many miles per $

Re: How many miles per $

You must be referring to CNG or LNG. There are currently no Heavy-Duty manufacturers delivering any LPG products in the US. Zero. No engines either. There just aren't. Again, there are some medium duty options, but still rare. No Heavy-Duty LP products. Never have been. You used to be able to buy a 190 hp 5.9 B series Cummins on LPG. That's about it for larger vehicles, and that doesn't get you into to Transit, Refuse and especially not heavy-duty truck.

I believe its all the above and Propane also
The FED has given huge incentives to convert fleet vehicles
Here are examples of LP usage

Mass Transportation Authority - Flint, MI


2011 Blue Bird Propane Vision 71 Passenger School Bus (6400) | Florida Transportation Systems, Inc.

West Allegheny to use propane-fueled buses - Pittsburgh Post-Gazette

This comes straight from the Department of Energy
Alternative Fuels Data Center: Propane Vehicles

Roush Industries Sees Sharp Growth In Propane-Powered Trucks, Buses ? CBS Detroit

There are other examples but you get the point.

I am finding that the 5hp lehr works very well.
I just ordered a larger boat and I will see how it does with that
I will start a new thread next month on how it works with the larger boat.
I believe Fuel consumption is going to be determined by weight/load
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

Aware of those links. None Heavy-Duty, that was my point. The Roush stuff is all Ford and GM light duty. All good.
 

aerobat

Master Chief Petty Officer
Joined
Jun 1, 2011
Messages
843
Re: How many miles per $

Re: How many miles per $

we have to remember that lpg tends to produce higher exhaust gas temperatures than petrol. so assuming the base engine is identical to a petrol variant we can expect a little bit lower longevity of the engine, especially on the exhaust valves and valve seats.
 

DirtyOldBoat

Petty Officer 2nd Class
Joined
Jul 16, 2011
Messages
120
Re: How many miles per $

Re: How many miles per $

we have to remember that lpg tends to produce higher exhaust gas temperatures than petrol. so assuming the base engine is identical to a petrol variant we can expect a little bit lower longevity of the engine, especially on the exhaust valves and valve seats.

Not really. Yes, propane engines are harder on the valves...but overall, they will last a lot longer. I would assume the Lehr engines are completely designed to run on propane so they should have no issues with the valves...
 

phillnjack2

Ensign
Joined
Apr 30, 2011
Messages
918
Re: How many miles per $

Re: How many miles per $

As for large engines not running on lpg that is 100% wrong
in the uk we have huge engines running on lpg , the largest engines made by ctapillar run on lpg and are used as generating plants running 24/7 in a lot of large factorys.
I dont know if you have the company called finnings in the states where you are but in the uk they are a big supplier and engine repair maintainence base for these engines.
The royal mail have them near me and those engines you can almost get insed to clean out the sumps.

LPG is used on thousand and thousands of the heaviest trucks throughout europe and the uk.
its not just for petrol engines, any 4 stroke engine diesel and petrol can run on lpg even outboards.
As for valves getting burnt out faster that is a myth, if the timming was kept the same for petrol then maybe so, but when running purely on lpg or most of the time then the timming is set different.
Also the valve seats and stems are nowdays built a lot strongerthan back in the 1960's and 70's.
maybe if you talk of very old engines before the days of unleaded then yes valves would burn, and do exactly the same with unleaded fuel.
LPG is liquid petroleum gas, its petrol, just higher octane than what we now get,the octane is around the same we used to get back in the 1960's in uk and europe.
99% of water ski clubs use lpg in their mastercraft and shi nautique's, in europe its selling big time on the canals and rivers.
Throughout europe its on the forecourts now just like in the uk.
its not a new thing ,lpg was used during the second world war on lots of engines including fast patrol boats.

There are lots of myths about the lpg , and most put around by those who have never used it, and those who dont
want it promoted too much (oil company's).
there are many other types of gas including bnatural gas that are used by fleet vehicles, the main problem with these is getting the fuel to be as clean as lpg.
Their octane seems to be a bit more up and down in terms of sability, but still much much cheaper than the petrol/diesel fuels here.
Petrol v8 engines do not produce as much torque on pump gas as they do on lpg that is a fact.
When i ran my v8 range rover for 9 years on the stuff it coukld pull large boat trailers up hill in higher gears no problem.
we found the fuel consumption to be about 2% less when looking at a thousand miles.
considering its under half price of petrol the savings are fantastic.
the only downside for me was having another tank in the back as well as the normal 90 litre tank of petrol.
next time i will have just a very small petrol tank and big lpg tank in place .
but when people say no heavy engines or heavy trucks thats nonesense.the american heavy engines are used and used a lot on lpg in the big trucks, i am a truck driver so i think i know what fuel ive used.
Man diesels, scania diesels, volvo diesles, cummins diesle, perkins, detroit ,renault ,magirus deutz, mercedes etc all make big truck engines of over 400hp horsepower and do use lpg, the catarpillar engines at the post office i think are 37 litres i will find out, i know the engines used on a lot of refuse sites for powering electricty are now in the 40 litre range and use lpg and some cng

catapiller uk are up in derbyshire, they run the whole site on massive engines and use gas to power the engines
lots of big industrial sites are now having engines converted instead of paying power companies for electricity.
Plenty of real heavy haulage are using it as well in the uk and europe.
you need to dig deep and go check out the big stuff and stop thinking about small 190hp engines, theve been on it for decades.

phill
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

Phill,

My background is Caterpillar, and I understand the use of LPG in heavies very much. When I said "heavy-duty" I meant heavy duty vehicles. Also, my company has a small factory in Leyland. I also understand the UK truck market. I absolutely understand the stationary gas (LP and natural gas) engine market as well. This is what I do for a living. There are no Heavy Duty vehicles of significance on LPG, anywhere. Certainly not thousands on LP. Methane (Natural gas), yes, LP, no. As for large stationary engines there are more of those than heavy trucks, but very few compared to natural gas. LPG and Natural Gas are not the same thing. If you are lumping together, that may why you are confused. With all of that said there are some cheapo LPG systems that inject say 10% LPG into the intake of a diesel. I am not counting those. They don't meet emission standards and do not make an economic case. And there are very few of those worldwide as well. Check your sources and get back to us. I am not posting this out of any reason other than accuracy. Trust me, I know of what I speak. It's all that I do ;)

I also know of your ski clubs on LPG, and I have seen them on Windemere before the speed limit change. I have posted about those boats here :)

And yes, I know Finning. They are large Cat dealer and have facilities in Canada, South America, Alaska, and the UK. I have partnered with them in all of these places. The engines you speak of are Methane probably. Royal mail may use LP in the smaller delivery vehicles. I have visited them regarding large natural gas vehicles (methane). The problem with the heavy duty vehicle claims that you are making is that there are NO LPG engines available of the size and power you are mentioning. Stationary is different as I have said, but you are still confusing them with natural gas I believe.

Edit; I guess I should read your post before I respond. Cummins has no LPG engines for heavy duty vehicles. Volvo have no heavy duty engines for LPG, MAN have no LPG engines for heavy duty, Scania have no heavy-duty engines for LPG. I am a supplier to Volvo, I was in Cummins head office two years ago discussing this exact subject. None of the manufacturers of these vehicles make an LPG engine of over 400 horsepower. Zero. Stationary, yes, vehicle, no. Got to their website and get me some specs. There are NONE.
 

aerobat

Master Chief Petty Officer
Joined
Jun 1, 2011
Messages
843
Re: How many miles per $

Re: How many miles per $

phillnjack , some statements you made seem simply not valid to me, but since i,m not a fully pro in LPG i googled a little bit about that .

wikipedia says that LPG displaces oxygen and so physically the cylinder filling is worse and so power output lower. at least in naturally aspirated engines.

i checked VW germany webiste and indeed - the golf bi fuel 1.6 naturally aspirated has 102 horses on petrol and 98 on lpg, the torque is also a little bit lower on gas.

with turbocharged engines running on lpg a higher possible turbo boost due to higher octane can equalize the power loss so a turbocharged lpg engine can produce the same power like on petrol- and yes, the VW polo 1.4 TSI bi buel has exactly the same specs on petrol and lpg.


when it comes to wear let me quote you a sentence from wikipedia:

"Not all automobile engines are suitable for use with LPG as a fuel. LPG provides less upper cylinder lubrication than petrol or diesel, so LPG-fueled engines are more prone to valve wear if they are not suitably modified"

here is the whole article :

Liquefied petroleum gas - Wikipedia, the free encyclopedia

i looked also at MAN and mercedes website for truck and nope- not a single truck appears to be for for sale on lpg , at least here.

so ,do you have some sources for your statements ?

saying that , i,m not against lpg, it might be a good idea in some parts of the world, and exhaust emmisions seem to be really better than on petrol. that also may apply to the new outboards .

cheers !
 

phillnjack2

Ensign
Joined
Apr 30, 2011
Messages
918
Re: How many miles per $

Re: How many miles per $

wikipedia is not the brains of the internet, its often very very wrong and there is plenty of duff info on there.

Now go to ford uk site or any car manufacture and they will tell you lpg is slightly less power blah blah blah.
its because its now a law in europe and the uk that if someone wants a new car that duel fuel the company has to supply it due l fuel at no extra cost to the customer for eco resons. now being as car manufacutures have been involved with oil companies for over 100 years i see no reason for them to help them out now.
abaout damaging valve seats,yes if youve got the very old pre 1980 valve types in your car, all cars that run on unleaded petrol have the hardened valve seats nowdays, unless you happen to have an engine built in outer mongolia by tirbesmen thats made from wood.
just go look around and see how many engines are used in industry alone on lpg its in the millions not just a few. maybe in the states you are way behind us in europe and the uk due to you not having exspensive fuel prices like us.
We are paying ?6.40 per gallon, thats over $10 us dollars for fuel and it seems to be going up monthly, diesel is a touch more exspensive as well than petrol.
Now torque is higher on lpg and if anyone says no, then they do know what they are talking about,ive worked on cars trucks,vans heavy haulage trucks, believe me i know a fair bit about torque on engines, my own vehicles torque on lpg at low and mid range improved by around anextra 20 -25%, thats a fair amount i think. top end is not worth talking about as its marginaly less0.000002%.
on a small 4 cylinder 2 litre petrol engine lpg is very noticable,the smoother pull away and less engine noise for starters, then the less throttle to stay in higher gears is even noticable on auto boxes. now go upto the 4 cylinder diesel engine of around 4 to 7 litre, the engines are so much smoother and quiet and again more power in the low to mid and equal at the top due to rev and speed limiters in the uk.But when you get two artic units (semi tractors) side by side and then both hit the gas the lpg vehicle will hust stream away from the plain diesel and not leave a big black cloud of soot. go look up rpi engineering and they can give you some info.obviously some people will never use lpg as they will not be convinced of it being any good, the same with trying to explain the benefits of diesel to petrol heads,it iant gonna happen... i have told it how it is and now its upto you i have had enough of this topic as its now gone nuts with wikepedia being used as a bible.. when its that bad its time to go.
 

DirtyOldBoat

Petty Officer 2nd Class
Joined
Jul 16, 2011
Messages
120
Re: How many miles per $

Re: How many miles per $

wikipedia says that LPG displaces oxygen and so physically the cylinder filling is worse and so power output lower. at least in naturally aspirated engines.

i checked VW germany webiste and indeed - the golf bi fuel 1.6 naturally aspirated has 102 horses on petrol and 98 on lpg, the torque is also a little bit lower on gas.

That's for "dual fuel" engines, which the Lehr is not. If you want to run both gasoline and propane you have to make sacrifices and you won't get as much power from either fuel as you could in a dedicated engine. If an engine is designed to run on only propane then it will make every bit as much, or more power than the gas version. In order to run comparably low octane gasoline you have to keep the compression and timing low, which isn't great for propane.
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

I agree 100% with that post ^^^^ +1000

I will add one comment. Most of us in the alternative fuels industry call that "bi-fuel", although dual fuel is used as well. Generally when we say "dual-fuel" we mean a diesel engine with natural gas or propane injected into the intake and in effect we are burning two fuels simultaneously. The terms are interchanged most often by regulators, as the emissions certification documents themselves use them the other way around. Major pain.
 
Joined
Feb 17, 2012
Messages
2,906
Re: How many miles per $

Re: How many miles per $

if you install a diesel fuel injector with a built in inductive ignition system to allow the diesel to run on lg then is it still a diesel?
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: How many miles per $

Re: How many miles per $

Yes. Compression ignition = diesel cycle. Man invented the cycle, not the fuel. Most common fuel for the diesel engine shares his name. Interesting trivia point. One of very few words in the English language that is a person's name and not capitalized.
 
Joined
Feb 17, 2012
Messages
2,906
Re: How many miles per $

Re: How many miles per $

Yes. Compression ignition = diesel cycle. Man invented the cycle, not the fuel. Most common fuel for the diesel engine shares his name. Interesting trivia point. One of very few words in the English language that is a person's name and not capitalized.

i dont believe on 100% lg it is a Compression ignition as they have to use a spark to ignite the lg on the large semi-trucks
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
LPG for vehicles

If it has a spark plug it is an Otto cycle engine. Could be bi-fuel (either or), dual-fuel (compression ignition and two fuels simultaneously) or dedicated (one fuel). Large trucks (5 axles, 80,000 lbs), there are no LPG options available. CNG/LNG yes, LP no. Both Otto and Compression available for large trucks and CNG/LNG. Limited though.
 
Top