Hi
@pauljygrant,
If you are looking are some free camping, plan the size of your solar panel/s based on your expected power usage.
There are plenty of different solar panel and battery setups and sizes to choose from when getting ready to free camp. What you need to do is look at what it is you want to do and keep running.
We free camp and use a 200W panel (2 x 100W folding) and 2 x 100AH batteries, CTEK 250S Dual DC-DC charger & solar regulator and a 2,500Watt inverter for the microwave, toaster, coffee machine, hair dryer and washing machine! Call if free Glamping more like it!! We have free camped for up to 9 days straight with this setup and no issues.
First thing is to look at what you want to run, the total AMPS all the items will draw and a day (Volts x Watts) and how long you will run things for.
Don't forget any portable electrical devices like cameras & phones. iPad and phone chargers typical draw 2.1Amp, and if left on once the device is charged, they still draw a small current.
The key thing from a battery sizing perspective is that for optimal battery life, do not draw the battery below 80% of the battery's AH rating. If you are using 100AH batteries, then you should as a guide, do not use more than 20AmpHours per day, per battery. If you have 2 x 100AH batteries, use 40AHrs per day. Some deep cycle batteries can be drawn down regularly to 60% of capacity with little impact to their life, but this is manufacturer and battery type dependant. Refer to the manufacturer's technical specifications.
At the end of the day, the critical part is also how much power you can put back into the batteries - this will also depend on where you are in Australia.
Assuming a "sunny day" and the 100W panel/s you are looking at with a 5.56 MAX wattage:
1 x 100W (5.56Amp) over 4 hours @ 80% efficiency = 17.8AH recharge per day
1 x 100W over 6 hours @ 80% efficiency = 26.7AH recharge per day
This is where it may be necessary to have 2 x 100W panels or a larger single panel to make sure you get a full battery recharge.
Looking at bigger panels:
1 x 250W (@13.8Amp) over 4 hours @ 80% efficiency = 44AH recharge per day
2 x 250W over 6 hours @ 80% efficiency = 66AH recharge per day
Put the Solar regulator as close to the batteries as possible. Run min 6mm wiring everywhere. We use portable solar panels because if van is in shade, we can move them anyway we want and keep them in the sun most of the day. They are tethered to the wan with a 6mm PVC costed stainless steel wire!
The guys I buy from are Vic based sellers:
Solar Panels - Low Energy Developments -
http://stores.ebay.com.au/Low-Energy-Developments?_rdc=1
CTEK, Cable, Fuses, Anderson Plugs, etc - AutoelecAU -
http://stores.ebay.com.au/autoelecau?_rdc=1
Batteries - hunt about, but I am still using the batteries I had put in the van by Jayco in 2012.
If you are going the newer Lithium battery, make sure you get the chargers that are designed specifically to charge at higher voltages than normal batteries.
Hope this makes sense and helps.
Cheers,
Rohan
