The basic question here is how long can I sit in one spot and still run the basic electrical equipment in my camper?
To answer this question, start with the battery. Solar panels aren't vary useful without a battery.
Calculate your maximum daily current load by multiplying the current draw of each item by the time in hours that it will be used. Somewhere on the WtW site is a list typical current loads for FWC/ATM equipment, but I'll be damned if I can find it with new search engine. I'm sure you know that if the equipment is rated in watts, simply divide by 12 to get the current draw. Figure about 4 Amps for heater and roof fan each and 5 Amps for a laptop computer. The big kicker in your list is the refrigerator. If you have a propane-AC-DC Norcold/Dometic, don't even think about running on DC unless you install a low-voltage cut out. Running down you battery to 0V is a sure way to kill it if you forget to turn off you fridge. I don't want to admit how I know this, but trust me, it's an expensive mistake. If you have an Engle style compressor fridge, it's a motor with a modest current draw. The fridge will run longer in hot weather - but that usually means there's more sun.
For an example, suppose you arrive at 25A/day. Now, ask yourself, how many days I may want to sit in one spot before I will be on the road again and recharging the battery from the truck's alternator? If its 3 days, multiply 25A/day by 3 and you will find that you need 75A of energy. Given various inefficiencies and extra margin, double it to get 150A and the less you draw down the battery, the longer it lasts. If you can use cheaper outside mounted deep cycle batteries, you may want to figure on a 50% margin, or 112A. You are still looking at hundreds of discharge/recharge cycles before the batteries loose their useful life.
Now, look at solar panels. The 85W Kyocera can be expected to deliver about 6.6A at peak sunlight to the charge controller. Depending on the charge controller, you will get anywhere from 6.5A to 5A. Since there is only one high-noon every day, and in the winter, the usable sun is on the order of 8 to 10 hours, and also figuring on how easily you can orient the panel to the sun, figure on rough average estimate of 3A for 8 hours or 24A/day.
With an 85A/h battery and an 85W Kyocera, you will run your battery down 33% to 50% over three days.
For batteries, you want 1 or more AGM deep cycle batteries. If you can mount the batteries outside the camper, you can get much cheaper deep cycle batteries, such as Costco Kirklands. The Blue Optima is 55A/hr, but Interstate and other manufactures have much better price/performance points, and 85A/hr can be had for about the same price. The Kirlands are about half the price (but must be vented!).
We went with a 125A/hr battery (about the largest single that will still fit under the seat), a 120W panel and a MPPT charge controller (to get the maximum efficiency). Not the cheapest set up ($1000 or so at the time), but we run 2 laptops and often for several hours, including in the winter with less light and the need to run the heater. (We are fortunate in being able to combine work and play.) We can comfortably sit for 3 to 5 days worst case, and about as long as we want in Saline Valley. we have been very, very glad that we added the solar system.
There are a lot of good resources on the web. Some of the home solar sites have excellent explanations for all of the ins and outs of solar. Try
http://www.altestore...rary-Articles/.
