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I'm looking to install a 22 kw Generac generator that will need to feed off propane. I'm also in the process of planning the propane tank installation and trying to estimate the size. Can anyone estimate the propane consumption of a unit assuming a nominal load? Any other considerations, warnings or recommendations would be welcome.
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Location: Regina Saskatchewan Canada
I can when I get home tonight. What is the coldest temps at your locale? Need that to size tanks. How long do you want to have fuel on hand for?
Blackhat
Bad experiences come from poor decisions. So do good stories.
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This will be of interest to me as well.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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Typically winter temperatures during the day are in the 30's and nights in the 20's. On very rare occasions it might get to zero at night for a couple of days with highs in the 20's. I'm in the Knoxville, TN area if that helps. I'd like to have fuel for at least 72 hours. The only other propane use is a fireplace that won't be used much anyway as they are so inefficient.
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You should be able to find that information on Generac's web site. Just look up the unit you're interested in.
If you still can't find it, Norwall Power Systems will have it.
For perspective, I have a Generac 15kw unit that burns about one gallon per hour at 1/2 load.
Hope this helps.
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Consumption will be about 3 gallon per hour at near max load. A 500 gallon tank will handle that load at your minimum temp and give you run time in excess of your stated. You can't just use tank capacity numbers, you need the tanks vaporization rate at the minimum temp expected. Up here with minus 40 temps, I would need 2 x 1000 gal tanks to make that rate but I would have quite a bit more run time. Numbers above are from Generacs sizing tables.
Blackhat
Bad experiences come from poor decisions. So do good stories.
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When I purchased my 22k NG unit I found that Onan-Cummins had better efficiency ratings than the Generac. YMMV
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I have an 8 kW Generac and it used about 100 gallons in 72 hours (near you, in Walland, TN). I pushed an LP furnace, well pump, several lights, freezer, fridge, microwave, 1700W commercial Bunn coffee machine, 65" TV, computer setup, etc. This was during the ice storm and zero degree temps 2 winters ago.
Do you really need a 22 kW? Also, listen to what blackhat said regarding usage. Allen Graham at Pioneer Heat and Air is very knowledgeable about the Generacs.
Fred
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Thanks everyone. Good info all around.
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The Generac guy told me to go 500 gallon for mine, we will have install done in a few weeks, same size as yours, two switches
Watch your fingers!!