How much does it cost to run an Onan 24/7

[cimplexsound]

I'm not your usual dry camper. I like to take my electricity with me wherever I go. Not used my Emerald Genset very much even though it runs good because I keep it maintained, but this time of year in the Southwest when air conditioning is generally not required I'd think running a generator would cost less. So I'm curious for anyone who has had experience boon docking with an Onan Emerald genset. If you want to keep it running 24/7 how much can I expect to pay in gas to keep the motor running continuously??? My generator has less than 600 hours on it and I put in new spark plugs, oil/oil filter a while back. Any educated guess is helpful as we might be boon docking during the winter months.

[winniman]

If you don't require air conditioning, you would only have to run the genny about four hours a day to keep your batteries up. We would normally do that for a few hours at breakfast, and a few hours at supper. If you had a smaller inverter type portable, the fuel consumption would be very little. I believe the genset would burn about 1/4 of a gallon per hour. It would depend on the size of the genny, and how much load was on it. I have a 1200 watt suitcase generator I carry for just keeping up with the batteries if boondocking. If I require more power, or don't want to get out the little guy, the big genny is always ready at the push of a button. My rv will run the furnace off batteries for one night, but wont complete the second night without charging. I have two deep cycle six volt house batteries.

[pasdad1]

What is your oil change interval ? 100 hours ? Or less ?

Probably better to let your inverter and batteries supply power 24 hours a day, and let generator charge up batteries. An auto generator start module can do this automatically if you want.

[theroc]

I'll take stab at a guess ...probably not too much less than $35 per day --probably a little more, however. It will be substantially over $1,000 per month. I personally would not want to spend that much just for power every month.

There are a lot of variables as to how much a gas generator will consume per hour. From what I've heard, it's anywhere from about .5 gallon per hour to 1.0 gallon per hour.

Let's use .5 gallons per hour and let's assume gas is $3.00/ gallon. .5 x 24 x 3.10 = $36 per 24 hours (at the very least, or so I'd assume). And this doesn't take into account the added maintenance costs for running it 24/7 ...this is just for fuel.

But as others have said, why would you want to run it continually 24 hours a day? Most things can be run on the batteries/inverter. Run the generator when needed to charge the batteries, to run a/c, microwave, washer/dryer, etc. And/or as said in the post above, install an AGS. I'm scratching my head as to why the generator would have to be run continuously 24/7 unless you're doing something intensive during the day and night ...such as running a business where you are consuming high loads or things that have demand for that type of power profile during most hours.

[twinboat]

Here is a fuel burn chart from Onan 4000.

Now you need to figure out how much power your using.

2000 watts ( 1/2 load ) is 16 amps.

[LETMGROW]

You are talking over 700 hours a month on your generator. 350 plus gallons of gas. I don't know how big your gas tank is but you will be breaking camp and going to a filling station often which will use even more gas to get there and back. Depending on your maintenance schedule you will be doing a few oil and filter changes monthly.
If running a generator constantly was such a good idea you'd see everyone else doing it.
Why do you feel the need to run the generator 24/7 anyway?
Lynn

[marjoa]

Originally Posted by cimplexsound

but this time of year in the Southwest when air conditioning is generally not required I'd think running a generator would cost less.

As others have pointed out this is not a good or cost effective plan.

Since you stated yourself that—air conditioning is generally not required—then there's really no reason to be running the genset. Get a portable suitcase solar panel to keep your batt's topped off to run what you need and everything will be good. Turn the genset on intermittently for the big stuff when needed.

[dons2346]

Take the chart twinboat gave you for fuel usage and then factor in the cost of fuel where you will be staying.
At full load .71 gph times 24 hours equals 17.04 gallons. Using a price of 3 bucks a gallon it would cost you $51.12 per 24 hours.
Now times that by 30 equals $1533.60 a month.
This does no include the cost of oil/filter changes.



Might want to rethink your plan

[RunningHard]

My 8k Onan uses about 1/2 gallon/hour. We dry camp 90% of time so I always make sure I am full of diesel before I stop. I run it when driving in hot climate all the time. I just change fluids and filters each year when I service the coach.

[Gary RVRoamer]

As you can see from the fuel consumption charts, it depends on the load on the genset. Get the manual for your model of genset and it will have the chart specific to it.


With near-zero load, most Onans are around 0.25 gal/hour. Even a light load, 200-400 watts, isn't going to be that much more. However, 24/7 adds up. At 0.3 gal/hour, it's still over 7 gallons/day, plus its noisy! Much smarter to use an inverter with a decent size battery bank and run the genset only to recharge batteries or for those times when you need more power, e.g. for a/c.

[cimplexsound]

Originally Posted by pasdad1

What is your oil change interval ? 100 hours ? Or less ?

Probably better to let your inverter and batteries supply power 24 hours a day, and let generator charge up batteries. An auto generator start module can do this automatically if you want.

The manual for my generator says it takes ordinary 10 W 30 motor oil like a car. It suggests changing the oil every 50 hours of runtime.

[cimplexsound]

Sounds to me like solar or battery bank power is better and to only run the genny as needed. I should have known That cummins doesn't make the most economical to run generator on the planet. I usually run the generator twice a month for maintenance. It costs me a dollar just to run the thing for a half hour. Of course being 4000watts might have something to do with it. That with almost no load on it. My compact portable generator is far better. I can run it for almost a whole day on a gallon of gas.

[cimplexsound]

Traditionally I only use generators for power outages except running them twice a month for maintenance. That and when Im traveling and want 110 AC power during those overnight truck stop overs where you generally can't plug in and are parked between a bunch of noisy commercial trucks. I like camp grounds that offer hookups as an alternative to using your generator. But if you want to watch TV what then?? How about a 110 AC power bank that provides continuous supply without use of a generator. As with most RVs especially motorhomes your 110 does not work if you are not plug in or don't have the generator on. Most full timers use 110 AC continuously around the clock. Thus the generator seems to be the only viable solutions for constant 110 AC supply in an RV off the grid since gasoline doesn't have to be recharged if you get the idea.

[pasdad1]

Originally Posted by cimplexsound

Most full timers use 110 AC continuously around the clock. Thus the generator seems to be the only viable solutions for constant 110 AC supply in an RV off the grid since gasoline doesn't have to be recharged if you get the idea.

If that is what you want, you get a large solar installation, large 12 volt —> 110 volt inverter and lots of batteries (preferably lithium). Generator only needed if it rains for couple of days straight and no sunlight to produce power.