Propane versus gasoline generator

Really good content here, thanks.

What type of generator? Built in, or portable?

If built in, what type of RV? Class A/B/C, or towable?

How will you use the generator?

What I would suggest for a generator fuel source greatly depends on the answers to the above questions.

To cut to the chase, the only area I might prefer propane is in a towable. Portable generator I would definitely want gas. A RV with a motor, I would prefer the fuel source that the motor runs on.

Even with a towable, I am not sure that the propane is the way to go (and I have a built in propane powered Honda in my 5th wheel. For little stuff like charging batteries, using the microwave, hair dryer, toaster, etc. propane is fine. But when I go and boondock and need to run the air conditioning, it just uses too much fuel. I think it would be much easier to fill with a 5 gallon gas can than to switch out the propane bottles.

Might do just fine with more battery and inverter. Maybe a small 1000 or 2000 watt portable just in case. Portable may also help if you want to set up 100 yards away on a hill or something. Solar would work in the right conditions and charge your battery the next day.

I purchased the Champion "Dual Fuel" 3500 watt inverter/generator when I bought my 5'r last November. Having a choice of fuels takes away that "not able to find LPG issue.

My 5'r has 2 30lb tanks and I bought 2 spare 30 lb'rs to use for backup, genny, camp stove and fire pit. So far I've only run the genny on LPG and have camped up to 5 days/nights on 1 of the 30 lb tanks while tee'd to the outdoor camp stove.

My truck is diesel so having emergency for the TV is a NA for me.

Also in my case, LPG is cheap since I get a $0.90 per/gal discount from my home LPG provider.

So for me, LPG is my first choice, but I still have the option to buy gasoline if it was the only thing available.

For astrophotography needs, I would think that a battery/inverter/solar setup would be about ideal. You're likely to be camping in a place with clear, wide-open skies, and the energy usage of the telescope gear and laptops is comparatively modest.

I have not purchased my RV yet, but this propane versus gas question is part of the decision process.

One of the main reasons I camp is to do photography of the stars with telescopes, and we need power for that.

So my needs are fridge, ac, furnace, stove, oven, and (for the astrophotography) multiple laptops and less than 500watts of telescope gear.

Given what's been written already, is the energy density issue my main concern?

Thank you all for the great answers. I am grateful.

Gumming up the carb doesn't happen with propane.
I have a propane gen. and I like it. But, I don't use it that much. Mine starts every time I need it. The exhaust is fairly odorless and clean. I use far more propane for my furnace or water heater than anything else. I haven't had much trouble finding propane filling stations either. In fact a lot of the campgrounds I've stayed at have them.
If I were going to run the generator a lot, like all day for the AC or something, then gasoline would be easier to deal with as far as getting and transporting the fuel. For my occasional use for a few hours now and then it works out great.

Propane does burn cleaner. There are no carb or bad gas issues with lp.
Propane is generally less efficient. An lp genset will burn more fuel vs. a gasoline genset. There is more energy in a gallon of gasoline vs.a gallon of lp.
Transporting fuel will vary based on the RV type. Motorized RV's gas or diesel will always be easier based on the engine type of the RV.
Towable RV's present more of a challenge. A toy hauler generally has a built in gasoline tank which works well for a built in gasoline powered genset.
However a towable 5'er generally has no gasoline tank. Portable gas cans or portable LP tanks are your only method.
Most fiver's comes with LP tanks already installed on board making a LP genset and easier solution from a transportation and storage viewpoint.
My 5'er comes with 4-20# lp tanks from the factory. Making a lp genset a viable solution for power.
I am a convenience genset user and lp works great for me. However if I were a heavy genset user I might consider a different fuel source.
Camping style, usage,and RV types are all factors to consider when choosing a genset fuel type

A couple 30# bottles will run the fridge, furnace, stove, water for an extended period.
If you plan to run the air conditioner 24/7 you may want to increase your propane supply. But then if you are worried about carburetor gum you may not be using it that much.
And I suppose the furnace does burn some serious propane as temperatures dip well below freezing.