How much gas does a generator use?

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ceemike

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Does anyone know how much gas a generator uses per hour?  I have an Onan 5.5kw & I would be running one or two roof air units.
 
That's kind of a broad question for that generator.  Are you using propane, diesel, or gas?  Using 2 A/C units will be using considerably more fuel than one, but I'm sure you already know that.  It also depends on what other electrical items you'll be running, and what load the generator will be running at.
 
It runs on gasoline & the only other appliance running would be the refrigerator.  I don't think it draws much current.  I'd like to get an idea because I plan to run the generator so I can use the front rooftop air unit while I'm driving.  I said I'd be using both because I figured that would be the worst case scenario.  I read somewhere that a typical 5kw gas generator uses about 1 gallon of fuel per hour.  That seems a little high to me.
 
ceemike said:
Does anyone know how much gas a generator uses per hour?  I have an Onan 5.5kw & I would be running one or two roof air units.

I run it mostly in the winter while dry camping - so the air is not involved. However, I do run everything in my office including a 3 station network that includes a desktop with quite a few peripherals. Whenever the genset is running, I am also charging my batteries with a 40A three stage charger, and most always will have cable news in the background w/no sound.

My gas usage runs around .6gal/hr with a 5.5Onan. Prior to this rig I had a Class C with the same usage and an Onan 4k micro lite genset -- and also got .6g/hr.
 
We use 1/3 to 1/2 gallon per hour but we seldom run the A/C (we prefer staying away from place that need A/C) and we leave the fridge on propane so it's mostly the electronic gizmos running.

Wendyd
 
Onan says your genset would use about 0.6 gal/hour at 50% load, meaning when producing a constant 2,750 watts (23 amps).  That's about what two a/c's would draw if running continuously.  One a/c is obviously less, about half that.  The fridge would be insignificant - maybe another 2 amp (240 watts) on average.

Your converter/charger also draws some power, but not much there either.
 
Our Onan 10kw diesel generator uses about .5-.6 gallon per hour.  Can't caculate exactly but that's close.  We run it frequently when driving because it's hot most of the places we go and we need the A/C to keep it relatively comfortable inside.  In January we spend a week boondocking at Quartzsite and diesel usage is negligible.  In addition to the diesel engine, diesel is used for the generator and our Aqua Hot water and heating system.

ArdraF
 

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