Generator fuel consumption

[rmorey]

Just got a new 14kW Generac Guardian generator set to LP fuel. I haven't had an opportunity to run it yet. Just curious if anyone had the same and what kind of fuel consumption I can expect. The dealer says its either on or off, but the book lists consumption or 1.85 gal @ 50% and 3.07 gal @ 100%. He just shrugged. Figured I'd ask the real experts. :thumbsup:

 

[s219]

Usually the manufacturer specs are right on the money from what I've seen. They test them pretty thoroughly.

 

[BHD]

most likely it sounds about right, on LP it may take a little more fuel, as there is less BTU Per gallon it may take up to 10% more as LP is only about 90% in BTU's of gasoline,

but most is the loading of the generator on the fuel it will use. I would guess that it would take at least a gallon to a 1 1/2 gallon just to run even with out load,

 

[kenmac]

I would say that the figures in the manufacture's manual, will be very close. I will also add that, these specs are for a new well tuned generator. As it gets older , out of tune, etc, it probably will use more fuel. I would try to keep the engine properly tuned to keep fuel usage as close to the manufacture specs. as possible

 

[/pine]

It's no different than anything else that runs on energy...the more you use the more fuel you will burn...
It's great to have a system on LP or natural gas...good luck with it...

 

[90cummins]

If Propane is perhaps $3.25 a gallon at 50% load it would cost $144 to operate 24 hours!

90cummins

 

[MossRoad]

If Propane is perhaps $3.25 a gallon at 50% load it would cost $144 to operate 24 hours!

90cummins

That's correct. If you're out of power for 10 days it'll cost you $1500.00 if you run it continually. A lot of folks don't realize that when they buy it.

 

[rmorey]

That's correct. If you're out of power for 10 days it'll cost you $1500.00 if you run it continually. A lot of folks don't realize that when they buy it.

We're off grid (solar) so, we seem to need to run about 1.5 - 2 hours per day from Dec 1 to Feb 1. (about 6 hours, every 3 days) The fuel cost is kind of irrelevant. Power, we were told, is $150k due south of us so...

 

[MossRoad]

Your case is much different than most folks around here. I was just telling my kid that was worried about getting stuck in the car in a snowstorm that in Indiana, you are rarely, if ever, less than a mile from a house, building, business, etc... It seems most folks around here purchase large generators to run their entire house during power outages, storms, etc... just for convenience, and they don't plan for how much that convenience will cost them, then are shocked when it consumes a couple hundred dollars worth of fuel in a few days after a storm.

 

[rmorey]

Your case is much different than most folks around here. I was just telling my kid that was worried about getting stuck in the car in a snowstorm that in Indiana, you are rarely, if ever, less than a mile from a house, building, business, etc... It seems most folks around here purchase large generators to run their entire house during power outages, storms, etc... just for convenience, and they don't plan for how much that convenience will cost them, then are shocked when it consumes a couple hundred dollars worth of fuel in a few days after a storm.

That's like roaming charges on your cellphone. Go somewhere and make a few calls. Come home and get killed with the bill! :shocked:

 

[MossRoad]

Yep. That same kid spent a week in a south American country doing volunteer work during Christmas break. We were very careful with that cell phone. :laughing:

 

[Industrial Toys]

If the power was out for some time, maybe cost won't be an issue. Any Fuel deliveries may be out of the question! This has happened again and again. Places like hospitals or Senior facilities get any available fuel first!

 

[CobyRupert]

Energy out (electricity)= Energy in (fuel) x efficiency%.

Your fuel usage is going to depend on how loaded the generator is. Typically your load is going to be bouncing all over the place as pumps or heaters cycle on and off.

Note: (Rough math here): 1 gal/hr of propane has about 26.8 kW of power in it, so 3 gal/hr is 80.4kW, so your generator's efficiency is about 17% at full load (14kW). I think that's about right for an internal combustion engine.

Edit: From wiki: Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%. -Hey!

 

[Stimw]

I saw a discussion on TV the other night about Natural Gas.
They said the price is up 41% in the last 2 years! So much for Fracking saving us.

I ran a 5.6kw generator (11 hp Honda) 24 hours for 12 days about 7 years ago. It used just under 1/2 gal an hour. Of course that was GW's gas!
It would cost about $40. a day now!

 

[90cummins]

Most people don't think about the fuel consumption (cost) when they install a large whole house backup generator.
Another detail most don't think about is if it is a wide spread power outage how will you get fuel, the gas stations will be closed!!!
When the power goes out we should be thinking about minimizing our energy needs to just survive the outage not continue business as usual...
90cummins

 

[MossRoad]

That's one of the reasons a lot of folks are going with natural gas fired generators.... even in most power electrical outages, the natural gas still works. However, they are shocked when the gas bill arrives the next month after a week on that big old genny running the entire house.

 

[kenmac]

If you have a NG furnace, you are paying for gas to operate it ,in addition to the gas to run the generator . Now your gas consumption has just gone a little higher

 

[MossRoad]

A lot higher.

 

[RalphVa]

Our 12.5 kw Isuzu diesel generator used 2.5 gallons of diesel over 14.8 hours last year.

Ralph

 

[DarkBlack]

Energy out (electricity)= Energy in (fuel) x efficiency%.

Your fuel usage is going to depend on how loaded the generator is. Typically your load is going to be bouncing all over the place as pumps or heaters cycle on and off.

Note: (Rough math here): 1 gal/hr of propane has about 26.8 kW of power in it, so 3 gal/hr is 80.4kW, so your generator's efficiency is about 17% at full load (14kW). I think that's about right for an internal combustion engine.

Edit: From wiki: Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%. -Hey!

If you want your post to be correct you will need to change a couple of your kW's to kWh's. It's a totally different measurement.