Roof vents and skylights

It is quite simple really once you determine your need. I have installed and moved systems from rig to rig including my boat. 

Our loads were light consisted of both AC and DC appliances ( computer, tv, satellite tv, computers, cd players,  phone charger's, pumps, lights,  that kind of thing).  The system could a lot less complicated if you are just wanting to recharge the 12 volt system and if it doesn’t need to be mobile. 

My system was designed for nothing really heavy. I have run a coffee maker but that kind of load demands a heavier converter than I had. I didn’t have a 12 volt fridge but I hear some of the new ones are pretty efficient. We used propane for heat, refrigeration, and heating water. 

We lived off the grid with the same configuration on the beaches of the Baja every year for four months for four years, toured mainland mexico for two years, travel to the arctic and Alaska, and tour the Atlantic provinces of Canada. The following components always met our needs.

Storage 

Four six volt golf cart batteries. Two sets of six volt batteries (connected in series)  connect to each other in parallel. That was more than enough storage to last a whole evening of satellite tv (no sun for recharging). The batteries in a confined area should be enclosed and vented to ensure the hydrogen (produced normally during recharging and discharging) is not ignited by an accidental spark.

Solar

Two 175 watt solar panels. That was more than enough to recover the energy used at night by mid day with normal sun exposure.

Regulating

On 30 amp controller that allows you to switch between volts and amps display to monitor panel performance especially if there on the roof and you can’t readily see if they are clean. Also the controller  should be able to perform and equalizing operation. It’s worth spending a little more on a good controller to regulate the panel output.

Converting DC to AC 

A 2-3000 watt controller to convert the 12 volt DC storage to the 120 volt AC needed. When you calculate your heaviest load try to double the size. I had a 2400 watt converter to cover a the demand of a 1200 watt coffee maker. I would even go higher if that was you intention. Caution to look for continuos wattage not just surge wattage. This is an area you can spend a lot. My experience says it isn’t necessarily necessary. I have used both with no notice operating difference. Pick one the suits your budget. My converter had a remote control that was just plug and play.

Connections

The wiring is quite simple just minding polarity. The important part is the size of the cabling. Between the batteries and the converter you need very heavy cables to handle the amperage being moved. Look for cables as thick as you thumb (3/0). For panels to controller and controller to battery use at least 10 gauge. 

Circuit protection

Fuses are needed in each of the two circuits. A 200 amp fuse and fuse holder the protect the circuit to the controller and a 30 amp fuse and holder for the panel controller circuit.

Transfer switch

If the converter and shore power are using the same circuits ( all AC house plugs) a transfer is required to protect the shore power AC and the converter AC from operating in the same circuit. Each of those source produce AC but at two different sine waves. If they operate at the time younwill most certainly blow your converter. 

if you intend to have converter power available to every ac circuit in the rig you would have to ensure that shore power is disconnected before turning on the converter. Seems easy but trust me it easy to forget.

There are at least three ways to approach this.

1). You can use the converter on a separate and dedicated circuit (simple).

2). Provide power from the converter using a transfer switch that magnetically opens the circuit to the converter the instant  the shore power is connected there by protecting it. 

3) Provide power to ever AC circuit from the converter but having a mechanical disconnect that physically separates the two circuits. When the converter is required you disconnect the shore power. When shore power is available you disconnect the converter. Caution this system can lead to inadvertently connecting the two systems at once which will most certainly blow the converter if it is not specifically protected for this eventuality. 

I used a transfer switch because we were in the habit of connecting and disconnecting to shore power when it was available. It makes life pretty easy. When there is no shore power the circuit to the converter closes and the converter becomes the new primary source. It is not an expensive switch and to the trained installer pretty simple to install. If you go this route find an installer.

I have used Discount solar in Quartzite, Az. They are very helpful and will help you design  your system to meet your needs. It is a good starting point and you can shop for savings a DIY from there. 

Hope this helps get you started.