On board 5th wheel generator

Regardless of the efficiency of fuel, the end result is consumption, and there is just not that drastic of a difference when comparing on the same model generator, at least not worth bickering about. The pros and cons of the convenience of obtaining fuel, fuel cost, and maintenance would be better things to consider when making a decision:

i.e Onan 6500 (note - fuel consumption at full load is identical between fuels)

No load
Gas - 0.4 Gal/h (1.6 L/h)
LP - 0.5 Gal/h (2.2 lb/h) 1.0 kg/h

Half load
Gas - 0.7 Gal/h (2.8 L/h)
LP - 0.8 Gal/h (3.5 lb/h) 1.8 kg/h

Full load
Gas - 1.2 Gal/h (4.6 L/h)
LP - 1.2 Gal/h (5.3 lb/h) 2.4 kg/h

Maximum output
Gas - 58.3 Amps
LP - 54.2 Amps

and you will run out of gas too.. how fast depends on how big an extra tank you bring with you.

broark01 wrote:
Propane has fewer BTUs of energy than does gas or diesel hence the reason it takes more, its a fact pure and simple.

1 gallon of diesel has 113% of the energy of one gallon of gasoline.
1 gallon of propane has 73% of the energy of one gallon of gasoline

Agreed but had the LP filled at the stick house last week, $2 per gallon, gas was $3.25 and diesel was $3.89 :B
Use cost per hour, not gallon per hour :W

Propane has fewer BTUs of energy than does gas or diesel hence the reason it takes more, its a fact pure and simple.

1 gallon of diesel has 113% of the energy of one gallon of gasoline.
1 gallon of propane has 73% of the energy of one gallon of gasoline

Aridon wrote:
My issue with the on board propane models is they really don't last long. When we boondock we stay for 6-10 hours with the genset running more or less the entire time. That would get me about a day on the miniscule propane tanks most rigs (even larger ones) come with. Sorry but I'm not filling my tanks every day or even every other day. If you boon dock so little that isn't an issue then you likely don't need to drop 5k+ on a built in to begin with.

We are getting ready to order a DRV and we are skipping gensets this time. Going to go the Honda route, bolt them down and run them from the trucks tank. Seems an inexpensive option and more flexible to boot.

I agree lp gensets are less efficient than gas.
My rig has a 80 lbs propane capacity. On board is all about convenience. 80lbs will last on most of my 3-4 day boondocking adventures.
On board will always be more expensive and more convenient than portables. No gas cans, no set up, no additional cables or wiring. Just push a button and you have full 50 amp electric.
There are no security issues. The genset is with the fiver at all times.
If the truck goes into town the genset can remain with the fiver without security worries.

I don't boondock for long periods but I like the convenience of push button power. My rig can be totally self contained when necessary.
When we stop for lunch we have A/C and microwave available. If we overnight during the summer we have A/C available. Nothing to set up breakdown or fill.
I had a set up similar to the one I posted above. I had a Subaru 4300is inverter genset mounted on a rear platform on my prior TT.
The 4300is set up was a nice compromise between true on board and portable,however that setup was not inexpensive nor was it quite as convenient as a true onboard
There are lots of camping styles,genset options,budget, and expectations. In the end there is no one size fits all solution.

My issue with the on board propane models is they really don't last long. When we boondock we stay for 6-10 hours with the genset running more or less the entire time. That would get me about a day on the miniscule propane tanks most rigs (even larger ones) come with. Sorry but I'm not filling my tanks every day or even every other day. If you boon dock so little that isn't an issue then you likely don't need to drop 5k+ on a built in to begin with.

We are getting ready to order a DRV and we are skipping gensets this time. Going to go the Honda route, bolt them down and run them from the trucks tank. Seems an inexpensive option and more flexible to boot.

352 wrote:
Make real sure you have a good working carbon monoxide detector. It is a matter of life or death.

A good method to mitigate against CO if you have an on board genny is to purchase and install a Genturi. You should test your CO detector too. Leaving your truck run while parked or hooked up to the fiver could cause problems.

Almsot every toyhauler comes standard with onboard generators. Not sure why they're not as popular on fifth wheels. I couldn't imagine not having a built in genny. It's nice to wake up never have to leave the RV push the switch & start it up to make coffee, warm the fiver up w/the fireplace, etc. wouldn't own another one without it. As for size. I wouldn't go less than 5500. It's nice to be able to run multiple ACs on those hot days if for no other reason cool it down faster.

Lantley wrote:

Atom Ant wrote:

Lantley wrote:
Hopefully photos are now viewable

Yep, they work now. Wow that is a lot of dock plate work, even the bumper. It looks great.

Is that something the fella could do himself, or did he have to go somewhere to have it made? I assume drilling holes etc is not a big deal, but the bends all look professional.

Actually it's relatively simple. The boxes were purchased and just bolted to the bumper with u clamps. Although I am concerned about the strength of the bumper. The bumper comes from the factory with the diamond plate I believe.
Once the boxes were bolted on, the gensets are just placed in the boxes and wired up.
The set up does not use a transfer switch,the RV cord simply plugs into the generators.

Sure makes a nice install!

Atom Ant wrote:

Lantley wrote:
Hopefully photos are now viewable

Yep, they work now. Wow that is a lot of dock plate work, even the bumper. It looks great.

Is that something the fella could do himself, or did he have to go somewhere to have it made? I assume drilling holes etc is not a big deal, but the bends all look professional.

Actually it's relatively simple. The boxes were purchased and just bolted to the bumper with u clamps. Although I am concerned about the strength of the bumper. The bumper comes from the factory with the diamond plate I believe.
Once the boxes were bolted on, the gensets are just placed in the boxes and wired up.
The set up does not use a transfer switch,the RV cord simply plugs into the generators.

The Onan is the way to go, very dependable and LP burns clean and you don't have to deal with gas cans. The extra cost is worth it when camping because it is much less hassle.