How Much Solar Do I Need For Camping & 4WD?

Powering your auxiliary batteries with portable solar panels has been something that outdoor enthusiasts have known about for a while now. From why it’s good, to why you should, we have demonstrated how you can get the most from your solar setup.

But what’s less understood, is knowing how much solar you need for your set-up. Let’s break down what you need to know to get started and introduce the REDARC solar calculator, so you can finally stop guessing, and calculate exactly how much solar you need for camping.

A Guide On Camping Solar To Get You Started

You're probably asking yourself, 'What size camping solar system do I need?' There's no hard and fast answer to this question. No two set-ups are the same and your needs will differ from your neighbours. Plus, with so many different-sized portable panels and blankets, it can be tricky to know where to begin.

Step 1: Calculate your total power load (Amps)

The first thing you need to know is that the power required by all electric devices, like your fridge, lights, and charging equipment, is measured in Amps. Amps is a measure of how fast an electric current flows. The bigger the current, the more electricity is flowing.

So, you need to figure out how many electrical loads (or appliances) you will have, and how many amps each appliance will draw. This information can be found in the product manual or on the label of every device.

Step 2: Determine the Amp-hours used per day

Next, you need to determine how long you will be using each item over 24 hours. This will give you the total Amp-hours used per day. Amp-hours

(Ah) is a measure of stored power. Amp hours is the number of Amps drawn, for the amount of time in hours that you draw that current.

Amps x hours = Ah

Step 3: What is the capacity of your auxiliary battery?

Finally, you need to know the capacity of your auxiliary battery. This is how much power it holds. The capacity of the battery or battery bank (along with the power usage) informs the power input that will be required to charge it.

Checklist to calculate camping solar requirements:

In summary, to work out how much solar to add to your camping power setup, you need:

The number of electrical loads to be run and the Aamps (power draw) of each
The total Amp-hours required in 24 hours.
The capacity of your battery

The number of solar panels you require will be determined by the amount of charge that needs to be returned to the batteries during the sunlight hours of each day.

How many solar panels do I need?

To answer the question, how much solar do I need for camping, it is best to compare solar panels by power rating or wattage.

Watts is the basic unit of power. The wattage of a solar panel determines the rate at which it will deliver to charge the batteries.

Volts x Amps = Watts

For example, you have a 12V vehicle power system and you need to replace 75A/h of charge back into your batteries each day. You have 6 hours of sunlight each day. You will need:

75Ah x 12V = 900Wh

900Wh/ 6h = 150W of solar panels

In reality, it is recommended that you always over-estimate your requirements by at least 20%, therefore you would need 180W of solar panels.

As part of your solar panel system, a solar regulator is important to ensure your solar panels are applying safe and efficient charge to the battery.

Camping Solar Power Calculation: Real-World Example

Let’s run a scenario to gain a better understanding of how to calculate solar power for a standard camping setup. Your calculations might look different if you are travelling with a family or powering festival camping — but this guide will get you started.

A typical Aussie weekend camping trip will need power for:

A fridge, let’s assume 351L, 4 amps over 14 hours
12V LED Light, 0.5 Amps over 4 hours
Portable stereo, 2.5 Amps over 2 hours
Phone charger, 2 Amps over 2 hours

Multiply the Amps by the hours used to get the Amp Hours for each appliance. Then add up the total Amp hours for the total load per day.

The total loads used per day is 67Ah, therefore this is the amount of power that your solar panels will need to contribute to charge the batteries each day.

To maximise efficiency and extend the life of a battery, the battery should ideally be discharged by no more than 50%. Therefore, this camping setup will need a 134Ah battery.

Let's assume it’s winter and there will only be 6 hours of optimal sunlight each day. So, how much solar is required to charge the camping battery?

Take the total Amp hours required each day, and multiply this by the voltage of the vehicle’s power system. For this example, our vehicle has a 12V power system setup for weekend camping.

67Ah x 12V = 804Wh

(804Wh/6h) = 134W of solar power

Including an additional 20% buffer, this comes to 161W of solar power.

Which camping solar power options are best?

Solar power that charges the camping battery can be supplied by combining a fixed solar panel, and a solar blanket. You could also combine a 150-watt fixed solar panel and a portable solar panel.

Using fixed and portable power together has many advantages. The portable solar panels or blanket can be moved within the campsite to optimally catch sunlight. The fixed solar panel is mounted to the vehicle roof racks and can continue to charge the battery when the campsite is packed up, or when driving.

Generally speaking and providing the weather conditions are suitable (not overcast), a 150W solar panel when paired with an in-vehicle battery charger will allow 24/7 use of a modern 60L fridge.

Use the examples above to calculate how much solar to add to your camping power setup

Now it’s your turn — see if you can work out your total solar power needs for a day out camping. You can find out more about the different types of solar panels on our website.

FAQ

How much solar power do you need for camping?

To work out how much solar power you will need, you need to work out what items you want to bring and the amp hours these appliances with draw. Once you work this out you can multiply the amp hours by 12V to work out your wattage hours. Assuming you will get 6 hours of optimal sunlight, divide your wattage hours by 6 to work out exactly how much solar power you will need.

Is 200W solar enough for camping?

To work out whether a 200W solar panel would be enough solar power for your camping trip you need to work out what you plan on bringing. If you get 6 hours of sunlight each day and have a 200W solar panel, you could use 1200Wh.

Will a 200W solar panel run a 12V fridge?

Yes, A 200W solar panel would be able to efficiently run a 12V fridge. Remember there are many factors to consider that may impact which solar panel you can use to run your fridge.

The compressor-style
The size,
Insulation
The efficiency of the fridge

How To Work Out Exactly How Much Solar You Need For Camping