Will try to keep it real brief though I just ran some thru some detailed testing on my EU2000 with a 160 watt measured resistance (lamp) load. This is pretty much the same measured load as my Pocono running at ~40 % convection fan speed ( 2 fans) with combustion blower running and intermitted feed motor. No consideration given for the stoker motor inductance load.
On eco mode under a constant 160 watt load, the unit consumes 2.2 gallons a day (24 hrs)
Generator was fed with high test. The system set up permitted me to measure the fuel usage very closely. Ran it for 5 hrs using 58.5 oz fuel, you can do the math to get to the 2.194 gallons consumed in 24 hrs. Pure data, no "about this much" , temp outside 55 F .
This means that a 5 gallon external tank** hooked up to the EU you can easily get 2 days with the stated load. Obviously running the same genny with a ~ 400-500 watt load with consume more, though not as much as you may think especially on eco mode. That will be my next test..... to represent a refrigerator intermittently running with the stoker on 24/7.
** see Wise Sales in Google, can also make your own for a lot less money .
Hope this helps some of you to think about doing some fuel thrifty emergency provisions.....
Keep Warm, my Friend