Caravan Solar Panels: The Future Is Now

While many caravan owners choose to spend their time in powered sites and caravan parks, solar panels are essential for anyone that is wanting to get away and travel under their own steam. Once an expensive accessory, caravan solar panels have come down in price substantially in recent years, to the point where they are now a standard and expected feature of all new builds.

But if you don't own a new build caravan and want to add solar panels, or are looking to upgrade your existing solar power setup, there are a few things you will need to know before you break out the ladder and start drilling holes in the roof of your caravan. In this Buyer's Guide, we will walk you through some of the basics of caravan solar panels, the different types currently on the market, and what you need to keep in mind when it comes to buying and installing solar panels for your caravan.

Let's start at the beginning: What is a solar panel?

A solar panel is an ingenious invention that converts the sun's energy into an electrical current that can be used to power all of the many devices and appliances that fill our lives. Solar panels are comprised of a number of photo-voltaic cells that are constructed from wafer-thin crystallised silicon, a material that generates electricity when it is exposed to sunlight.

How does a solar panel work?

The energy generated by the panels passes through a solar charge controller, which regulates the voltage and amperage before it is used to charge the batteries in your system. This energy (which is in DC form) then flows from your batteries and through an inverter, where it is converted to AC electricity that can be used by your lights and appliances.

Are there different types of solar panels?

Yes there are. The type that most people are familiar with, and which you will see most often on the roofs of homes and caravans are fixed solar panels, which are large, rigid, and tend to be attached to metal racks or mounting brackets.

In recent years, portable solar panels have also come onto the market, and there are now two different types available: folding panels and solar blankets.

Folding panels look much like fixed solar panels but are built with hinged sections so that they can be packed up similar to a camping table and transported more easily, while solar blankets are thin, flexible and lightweight, allowing them to be packed down even smaller and spread out on any flat surface, such as a car bonnet.

What are the benefits of the different types of solar panels?

While all solar panels perform the same function, each type has different advantages. Fixed solar panels are favoured by caravan and motor home owners because they don't need to be set up or packed down each time you make camp, and can charge your batteries while you're driving to your next destination.

Folding solar panels tend to be more common for tent camping, as campers don't have the available real estate of a caravan roof and need the ability to reposition the panels as the sun moves over the campsite, while solar blankets are great for those who have tight weight limits, or only need to power a single appliance such as a portable fridge.

How many solar panels do I need for my caravan?

As with anything caravan-related, the answer depends on your lifestyle and how you use your caravan. If you spend most of your time in powered campsites and just want to keep the lights on for the occasional times when you aren't connected to mains power, you can get away with a single 150W panel.

However, if you plan to spend significant amounts of time off-grid or have a power-hungry setup with a refrigerator, microwave and water heater, you are going to need much more than that. Solar panels differ in how much power they produce, with most caravan solar panels producing between 100-150W. So, before you start investing in panels, you will need to figure out your approximate power needs and how many panels you will require to meet those needs.

The easiest way to do this is to take the power output of your major appliances and multiply that by the number of hours you will use them each day - the resulting number is how many Watt-hours you can expect to use in a given day. Below, we've broken down the power needs of some common appliances:

Microwave: 1000W x 10 minutes per day = 100 Watt-hours

Single LED light: 10W x 6 hours = 60 Watt-hours

Laptop charger: 100W x 2 hours = 200 Watt-hours

Television: 200W x 3 hours = 600 Watt-hours

60L caravan fridge: 60W x 24 hours = 1,440 Watt-hours

This brings the total number of Watt-hours to 2,400 - but remember, the sun doesn't shine all day long, nor with the same intensity throughout the day. To determine how many panels you need, you should divide your total Watt-hours (in this case, 2,400) by the amount of sunlight per day - in an Australian, this is around 6 hours per day of peak sunlight.

2400W ÷ 6 = 400W. So, based on the numbers we've used, you need to produce 400W of power per hour, which will require 2-3 160W solar panels. This is obviously a quick and somewhat incomplete example but one which you can replicate more precisely based on your own needs.

What do I need for a solar panel system?

Solar panels are only one part of a complete setup however, and unless you plan to only use your appliances when the sun is shining, you'll need a way to store that energy and release it at any time of the day or night.

Other than panels, batteries are the most essential part of any solar setup. Here at Shop RV parts, we stock a range of lithium batteries from well-known brands including Sphere and BMPRO that are designed with caravan owners in mind. Batteries are often the most expensive part of a solar setup, so it is important to figure out how many you require to avoid buying more than you need - for tips on how to do so, you can read our Battery Buyer's Guide here.

Because solar panels produce power in uneven voltages and amperages, you will also need a solar charge controller to regulate it before it can charge your batteries. We stock several different solar charge controllers from brands including Dometic, Sphere and more.

The final piece you may wish to add to your setup is a battery monitor or battery management system. A battery monitor will allow you to see how much charge each of your batteries has, as well as keep an eye on their overall degradation, while a battery management system will ensure that your batteries are charged and discharged equally.

If you're thinking of investing in solar panels for your caravan or motorhome, check out our range today.

With one of the largest selections of caravan solar panels, batteries, chargers and controllers in Australia, we've got you covered when it comes to shopping for your next solar setup. In the meantime, you can read through our other Buyer's Guides for information on everything from caravan diesel heaters and air conditioners to portable fridges, privacy screens and safety essentials.