I think you need to spend some time with your battery monitor
and see what the devices you are using ACTUALLY consume. If my VHF took 48 amp hours I think I would switch to a hand held unit and buy AA batteries... Go use your boat for some time and see what you are actually consuming in a 24-48 hour period. My fridge set up is not so great but it takes about 60 amps in a 24hr period on the chesapeake in high 90* temps. We run cabins lights, stereo, inverter
for the coffee pot and bean grinder and computer, anchor light, electric
flush head(s), FW pump, radar
, and I normally wake up to about -80amp hours on the meter. Autopilot
depends a lot on what sort of seaway, calm chesapeake its 8-10amps when running, rough offshore
15-18amps when running. I have improved things some with Alpenglow cabin
lights, LED anchor light, only 1 pot of coffee. But I also dont leave the VHF on, I dont like hearing all that crap on the radio
all day. Autopilot will likely be a big draw but you wont be using it sitting on the hook in paradise. I dont mind running the engine
some to offset the AP, its nice to make hot water
and get a shower
We are setting our boat up for extended live aboard tropical cruising and I am hoping to afford (4) 135watt panels. With them I hope to make 180amps on a really good day. I am hoping can get my 24hr consumption
to stay within 100amps when on the hook and I am using an 800ah bank.
Anyway my point here is that the approach of reading the manuals
and estimating how much time you might use a device is not the best way. Far better to use the real world and gather some epirical data on YOUR usage before spending on a theoretical system.
Of course Gord is right too, put on as many of the damn things as you can afford...