Gas vs. Propane Generators

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ESPNRV

Member
Joined
Aug 17, 2009
Posts
5
Location
Chicago, IL
Can anyone point me in the direction where I can find a post on gas vs. propane generators for RV's?  We are looking at replacing our Onan 5.5 kw gas powered generator with a 6.5 kw propane powered generator (Not portable but built into the RV)that would be tapped into our existing propane tank.  Any 'Pros' and 'Cons' anybody can think of about these two options would be greatly appreciated.  I'd love to hear from people that have used both personally also.  We travel from very cold climates to very warm climates quite frequently if that matters also.  Thank you.

-Scott
 
You should get a bigger propane tank, propane generators are very thirsty and less efficient.  I would suggest you stay with the gas powered generator.
 
I have met RVers in filling stations that complained about LP generators, even to the point they were going to trade the rig in on a diesel.

Russ, WB3FQI/6
 
Here's a discussion about propane generators versus portable gasoline generators that might give you some information. I have an Onan propane that I'm happy with. Very reliable with little maintenance. The downside is that it uses a lot of propane. 
 
The 6.5LP model is available as both liquid and vapor LP feed models.  If you get the liquid model, you will have to add a fuel line to the propane tank itself, whereas the vapor model can tee off the existing vapor outlet (I think).

Onan says the 6.6LP uses about 3.5 lbs/hr at 50% load, which is only 27 amps. 5.3 lbs/hour at full load (54A).  That's a lot of propane if you need to run the a/c on a hot day
 
Had an Allegro Bay-loved it and had mixed feelings about the LP generator. If you boondock for any length of time forget it! We have a diesel now and the difference is like night and day. Its hard to tell the consumption when it runs. Very miserly and it seems to love being loaded.
 
For our events we will run a flat screen TV (exterior), exterior stereo system, internal lights and TV's (2), fridge, and possibly our AC (warm weather climates) for about 3-4 hours per event (about 30 events) and then for a couple of hours while on the road traveling to and from events.  It sounds like the propane should be able to handle all of these, the question is just how well will it do that for about 6 months?  Our gas 5.5k generator lasted us about 2 seasons and is just about completely shot but it never had a problem with the load.

-Scott
 
I do not think propane will make your generator last longer, I do not know what propane cost in most of the country but in NY it is expensive, and not all that available, obviously its easy to find gasoline and buy at the cheapest place you find, on the other hand propane does not go bad sitting in the tank when you are not using the rig, the exhaust fumes are safe but the exhaust system will most likely not  last as long as a gasoline generator, as a byproduct of burning propane is water.  Happy shopping! :D
 
There are a few different reasons for using one or the other fuel for a generator.  In the RV world you choose the fuel you have the most of as a general rule.

SO if it's a Class A with a motor and a big fuel tank to propell it down the road.. You use that fuel. Gas or Diesel, Why, cause I carry up to 70 gallons of it, that's why, I only carry about 25 of Propane.

If it's a trailer, you don't have a gasoline or diesel tank.. but you do have Propane tanks  So.. There you go.

Other considerations is proapne burns cleaner, mostly water out the exhaust, so you can use it indoors.

Propane also has a much, much, much, much, longer "Shelf Life" (Gas anythign over about three months you need to worry and six you shoudl toss it, Diesel.. I'm not sure but I've seen some very nasty diesel fuel too.  Propane basically never goes bad making it the ideal "Standby" fuel)

But for RV use you use the fuel you have the most of.  Your main engine fuel if it's a motor home.
 
Yikes!  Combustion from propane fueled engines may be cleaner than gasoline or diesel, but they still produce carbon monoxide and definitely should not ever be used indoors! ???  I'm sure you meant something else. Whew!

In my business, I use generators all the time, from 6KW & 9KW propane generators to 35 KW diesels. 24 hours of operation under 80% load with either the 6KW or 9KW propane unit, you can expect to use nearly all of a 100 lb tank of propane. There's more energy in the same amount of gasoline, therefore you'll burn less per hour for the same amount of kw used. Most RV's do not carry enough propane to provide you a continuous 24 hours of full load operation. Then what, detach your tanks or worse break down camp everyday to find the nearest propane station? Up to you.

The true benefit of propane or natural gas generators vs. gasoline or diesel ones would be for emergency standby generator attached to your home or business. Since the propane and natural gas can be stored indefinitely without degrading like gasoline or diesel can, it makes an ideal fuel choice for emergency generators. Additionally, in most natural disasters [like Hurricane Katrina, etc], most natural gas lines were still online,and propane was more readily available than gasoline or diesel. This was from my general overall experience with Hurricanes Andrew,Hugo, Charley, Francis, Jeane, Ivan, Katrina, Rita, Wilma and Ike. 

So being forced to pick a fuel for or RV boondocker generator. I'd stick with gasoline [they are the least expensive], unless you already have a diesel powered rig that you can tap into.

Hope that helps


 

John From Detroit said:
There are a few different reasons for using one or the other fuel for a generator.  In the RV world you choose the fuel you have the most of as a general rule.

SO if it's a Class A with a motor and a big fuel tank to propell it down the road.. You use that fuel. Gas or Diesel, Why, cause I carry up to 70 gallons of it, that's why, I only carry about 25 of Propane.

If it's a trailer, you don't have a gasoline or diesel tank.. but you do have Propane tanks  So.. There you go.

Other considerations is proapne burns cleaner, mostly water out the exhaust, so you can use it indoors.

Propane also has a much, much, much, much, longer "Shelf Life" (Gas anythign over about three months you need to worry and six you shoudl toss it, Diesel.. I'm not sure but I've seen some very nasty diesel fuel too.  Propane basically never goes bad making it the ideal "Standby" fuel)

But for RV use you use the fuel you have the most of.  Your main engine fuel if it's a motor home.
 
This is great everyone, thank you for your input.  For those of you that did or do currently use a propane generator have you found a constant national source to fill up at?  For example do all BP stations have a Propane fill station?  Or would I be looking for independent retailer everywhere I go?  Thanks again for the input.

 
You will be looking for a different independent in most places.  However, nearly all Flying J truck stops have propane, and there are regional chains of LP gas dealers you could use.
 
Based on your anticipated usage, I would recommend a gasoline engine GenSet. I have a propane genset, and am satisfied with it......the reason I have propane instead of diesel is because of the initial $4,500 cost difference. We seldom use the genset, and could not justify the price difference.

Having said that, for cold weather operation do NOT plan on a vapor LP genset.  Here's what a GenSet expert told me: "If you're never going to use a propane genset below about 45F, then a vapor withdrawl system works fine most of the time. On a cold enough day with the right (or wrong) amount of propane in the tank, there might NOT be enough propane vapor to run the genset under load - it can, singlehandedly, be your single biggest user of propane. If it's cold enough, running just the genset might be enough to use up all the vapor available. It takes heat to turn propane into vapor, and if you're running the furnace, the water heater is on, and you try running the genset to charge up the batteries that the furnace is running down.... and the genset starts, then starves out at the same time that the furnace and water heater have a 'flame failure' shutdownl...." That's the reason you would want an LP liquid genset instead of LP vapor.

 
FYI  cost of propane Vs gas.

In 2008, propane cost $42.67 per 1 million BTUs when used for heating.[25] This is equal to $4.86 per [gallon gasoline equivalent].
 
I have decided to go with the gas powered generator.  Thank you all for your input, it's much appreciated and it was a BIG help.
 
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