I have retroed a Westy and in the process of Full Solar for my 2001 SMB
I have done quite a bit of homework
IMHO:
Ya need to know:
-Figure out your needed watts or amp hours per day
-For this you need to know the amps for each appliance run
-There is some magic conversion for all this
-I use
http://www.affordable-solar.com
-How many average hours of sunlight
-How many amp hours can be stored in your batteries
-THEN you can determine panel size/watts
For instance:
-I calculated
-4cf fridge
-led lights 4 hours per night
-dvd player/tv 3 hours per nite
-fans 6 hours per day
-charge cell phone
-laptop 3 hours per day
-sterio hooked to iPhone 3 hours
-gas/lp/smoke alarms
-water pump
I am at @ 1200 watts per day
My two 180 watt panels will just about make that
I have 420 amp hours of battery storrage
I figure i can run indefinatley with no shore power
my story and i am sticking to it
if ya all want specifics, will post my calculations and equipment specs
FYI
all my parts, two panels, controler, remote display, isolator, fuses, batt temp
etc shipped to Southern Cal was $2,300
bw