Is 1.6 to 2.0 days autonomy enough?

It does all come down to your loads and sun... Just to put some numbers out:
http://www.solarelectricityhandbook.com/solar-irradiance.html

Scottsdale
Average Solar Insolation figures

Measured in kWh/m2/day onto a solar panel set at a 56° angle from vertical:
(For best year-round performance)

Jan	Feb	Mar	Apr	May	Jun
4.95	5.44	6.48	7.11	7.03	6.77
Jul	Aug	Sep	Oct	Nov	Dec
6.21	6.01	6.40	6.03	5.36	4.79

So, 3 hours a day of sun sounds a bit low--Winter is obviously worse for most people. For the above example, lets use 4.79 hours of sun minimum (long term average) for December:

• 6 * 180 Watt panels * 0.52 typicall off grid AC system eff * 4.79 hours of sun (December average) = 2,690 WH per ave Dec day

Now, I try to separate between "base loads" (ones that you need all the time) and optional loads (watching TV, fan, etc.--Whatever is "optional" in a small RV) and run 50% or 65% of the daily predicted loads. Lets just use 65% for now:

• 2,690 WH per day * 0.65 base load fudge factor = 1,749 WH per day base load (you make up with genset if more power needed during bad weather)

Assume you are a hard working AT guy and need 12 hours per day of power (8-10 hours per day, on-call emergency, a little web browsing/reading):

• 1,749 WH per day "base" * 1/12 hours per day runtime = 146 Watt average load

A lap uses something like 30-60 Watts, leaves the rest for printer, networking, LED lighting, radio, or even 2nd laptop.

So, sounds doable even in winter (guessing your location via IP address). Of course, moving in an RV -- May not pick such sunny climates down the road.

But does show that running a large desktop computer + screen + networking + heavy printing usage with a laser printer--May be diffult to do (something like 300 Watts).

Setting up laptop for lower power, auto sleep when not used, etc. all are important.

Anyway--Just an example of the math and assumptions... Using a small/fuel efficient genset like a Honda eu900i (900 Watt genset, ~720 Watt recommended continuous load--80% of rated capacity). You will get, very roughly 3,000 to 3,500 WH per gallon of fuel of fuel (with reasonable electrical loads).

Another neat thing about the Honda eu1000i (and others in the eu family) is that you can get a replacement fuel cap and connect a fuel hose that can be dropped into a fuel jug or connected to an outboard tank. There is a small fuel pump in the Honda, and with full genset tank and hose, it can draw fuel directly from a larger fuel tank (extended runtime). Can make those genset days a lot less frustrating.

https://www.amazon.com/s?k=eu1000i+extended+run

I got the magnetic tipped oil plug... Worked great on my eu2000i gensets (now old, keep pickled for emergency power needs). I don't know if it will fit the eu1000i or not.

With a Honda eu2000i, you can run a 20 to 40 Amp @ 12 volt battery charge maximum (depends on the exact charger, also altitude of genset).

A lot of the food trucks in our area use a Honda eu3000i--But that is probably much bigger than you need or will want to pack around. The eu2200i should be a nice option too, if you need more power (but more fuel, larger/heavier genset, etc.).

Regarding the numbers above, they are pure guesses... And may or may not reflect your needs.

-Bill

Glad it was somewhat helpful for your needs (I really like to work with "real numbers" for a poster's needs, rather than just give the same canned answer or two. Saves lots of hand waving and going back and forth about things that "don't fit the situation".

Regarding the gensets... Inverter generators should be operating at something like a minimum of 25-50% of rated capacity for best fuel consumption.

Non-inverter generators (gasoline), more or less their minimum fuel flow is pretty much at 50% of rated power. When, for example running at 25% of rated load, those gensets tend to still draw 50% fuel flow.

Keep your loads and support equipment (like gensets) relatively small... Oversizing will simply just be a waste of money, space, and weight (and fuel).

-Bill