Is there a rule of thumb as to how much fuel is used per horse power with a generator in use.

For example: A 11 HP generator uses "X" gallons in 24 hours
Or a 8 HP uses "X" gallons per hour

 

I don't think it would be possible to say how much fuel would be used. It would depend on how hard it was working. My 11 HP Onan burns a little less than a gallon an hour running the basics in the house. Heat lights pump frig ect. There are probably more efficient units than this one out there. RW

 

It really depends on what the load is. I do Hardwood Floors and when we install a floor (using only 110v) on our 16hp Vanguard Briggs (10000 watts) 10 gallons of gas will get us 12+ hours of run time but if we are Sanding a floor (using a 220v 30A machine) We may only get 6-8 hours of run-time. We also have a 20hp Honda (13000 watts) that uses a little more than the briggs does. I dont know if that helps, but thats my experience.

 

Yes that does help guys
So ball park a gal per hour or a bit more if I have tools going.
Im not trying to be precise but just to have half an idea as to how much gas I will use if power is out for a day or two

 

8-10hp engines will use far less fuel than a 16-20hp engine, so bear that in mind.. On the excessive side you could say 1GPH.

 

I agree with everyone here. Amount of gas used will depend on the load. My snowblower is a 8 hp 1 gal. gas tank. 1ft of light snow I will use 3/4 gal. 6" heavy wet snow, I will use 1.5 gal.