What you need to know about fitting solar panels on your caravan/vehicle

What you need to know about fitting solar panels on your caravan/vehicle
16/03/2018 GCCEM

Fitting Solar Panels on Caravans on the Gold Coast

Planning to go off grid on your next camping trip in or around the Gold Coast? Or want to avoid the pricey powered site costs in caravan parks and become energy self-sufficient?
If the convenience of having electricity without having to plug into a socket sounds appealing, then fitting solar to your caravan or vehicle on the Gold Coast will be a great investment. Read on to discover more about these devices and the installation process.

How do solar panels work?

Simply put, solar panels convert sunlight into electricity. They do this by using a series of photovoltaic cells that when exposed to sunlight create an electrical current. There are several different types of solar panels that each have their own benefits and drawbacks but for automotive use the main types are Polycrystalline, Monocrystalline & Amorphous.

What components does a solar system include?

There are a few components that you will need to make functioning solar system, these are:

  1. Battery

For typical caravan installation this will include one or two deep cycle batteries with around 100 amp hour capacity each. These range in price and performance from cheaper lead acid batteries, to better performing AGM and the top of the range Lithium. Which battery to choose is another subject entirely but you will have to make sure of a few things including,

  • The charging system matches the type of battery.
  • The battery is suitable for the installation location
  • The battery has the capacity for the application you require.
  1. Solar regulator

Automotive solar panels are designed to output more than 12V, generally they will output around 17V-20V. Connecting this directly to your 12v battery system will clearly cause issues. The Solar regulators will take a solar input of 9V-32V and convert it to a useable supply of around 13.6V. Better quality regulators will vary voltage to efficiently charge you battery without damaging it.

  1. Solar panels

Deciding on how many and what size you require can be difficult. Limiting factors such as mounting space and budgets play a big part on this one. Our advice though is to always try and go bigger than you think you need and try and stick to quality brands, remember buy nice or pay twice…

What are Amp Hours?

Much of the calculations around designing these systems refer to Amp hours, so what is it? Amps are electrical current, that is, how many electrons are passing a given point every second. Amp hours is a measure of current over time. So a 100Ah (amp hour) battery can discharge 1 Amp every hour for 100 hours until it is completely flat or 2 A every 50 hrs and so on.

How much solar power do you need?

If you’re considering solar panels for your camping set up, there are two main factors you should consider, firstly, what size battery do you require and secondly how much will it need to be recharged each day. For this exercise we can assume 1 x 100Ah battery is being used.

So what will be running off your 12V system?  If you are running  a  fridge, TV, lights, phone charger and coffee machine  you’ll have to install a set up that is able to generate and store a large capacity. However, if you’re simply looking to run some LED lights and charge a phone, you can opt for something smaller.

There are many online calculators that will help you do the math on what is required here but to provide an example of a common setup we would come across. we have provided an example below.  This obviously differs vastly between all types of equipment and set-up and is meant as a guide only.

Items in caravan/vehicle Current Draw (Amps) Time used / day (Hours) Total Ah (Amp hours)
Fridge 3 24 3×24=72
Phone/tablet charger 1 4 1×4=4
LED Lights .5 5 0.5×5=2.5
Total 78.5


Looking at the above table you will have a daily current draw of 78.5Ah. If we assume you have a 100Ah battery we can look at the below table to compare different system sizes.

This is a very generalised table, provided as an example only as there are many factors that will determine charge rates including weather, system design, manufacturer, fridge temperature selected and so on.

Solar system size Approximate panel supply @ 8hrs/day Discharge rate / day Free camp days
No Solar 0 78.5 – 0 = 78.5Ah 100 / 78.5 = 1.3 days
80W 5A x 8hrs = 40Ah 78.5 – 40 = 38.5Ah 100 / 38.5 = 2.6 days
120W 8A x 8hrs = 64Ah 78.5 – 64 = 14.5Ah 100 / 14.5 = 6.9 days
150W 10A x 8hrs = 80Ah 78.5 – 80 = -1.5Ah 1.5Ah excess power / day
200W 14A x 8hrs = 112Ah 78.5 – 112 = -33.5Ah 33.5Ah excess power / day


From this table we can see that the optimum system size would be greater than 150W from this point you are generating excess power/day. If you then factor in other variables such as poor weather or higher fridge load, a 200W system would ideal. The 200W system would also only require around 5-6hrs of good sunlight to fully charge the battery.

Should you choose a mounted or portable solar set up?

You can either mount your panels to the caravan’s roof or use portable panels instead. Fixed panels help prevent theft as they are fitted securely to the roof and also take no setup. Portable panels offer more flexibility as you can move the panels to face the sun without having to moving the caravan and installation is cheaper to install, but  you’ll want to make sure you have extra space inside your caravan to store the panels when they’re not in use. Because they must be carried around they can also be subject to more damage.

How does installation work?

Portable solar panels are nice and simple, as long as they have their own regulator/converter you can just hook them straight to the battery. Fixed panel installation is a little more difficult, you’ll have to consider things like how to attach them safely, where do cables need to be run and cable size required to prevent voltage drop.

You can undertake your solar panel installation on your caravan on the Gold Coast yourself, if you’re handy with wiring systems. However, we’d recommend you get a professional to help sort it for you.

You can undertake your solar panel installation on your caravan on the Gold Coast yourself, if you’re handy with wiring systems. However, we’d recommend you get a professional to help sort it for you.

Caravan Solar Panels on the Gold Coast

Taking a trip out of the Gold Coast? If you would like any advice on the installations we perform or to request a quote, just give our friendly team a call to discuss.