A Guide to Off Grid Solar System For Your Van

One of the most important aspects of any van build is the off grid solar system. If you want to be able to fully embrace vanlife and head off grid for a few days or longer, then you’ll need a good solar power system in your van.

This will make sure that you’re able to keep your fridge running, lights on, water flowing and phones fully charged, even while spending days camped out on the beach or in the outback. For non-electricians, it can start to become a bit overwhelming with unusual terms you may not be familiar with while researching solar system set-ups. 

With this guide, we delve into everything you need to know about off grid solar systems for your van and what components you need to be able to live vanlife to the fullest.

Basic Electrical Terms to Know

When you start researching off grid power systems for your van, you’ll come across lots of terminology that you may not fully understand. We’re going to break down some of the common terms here, so you’ll be more informed when you start to read further about different electrical components.

• DC Power: Direct current (DC) is the only type of current that batteries can supply on their own. For van electrical set-ups, you will have a battery that can provide DC power, and anything that you connect to your battery will receive DC power.
• AC Power: Alternating Current (AC) is the type of electricity that your local power plant supplies to houses and buildings. When you plug anything into an outlet in your house, it receives AC power. If you want to get AC Power while off grid in your van, you’ll need an inverter (more on this below).
• Amp (short for ampere): A unit of measurement for quantifying the rate of electric current flow.
• Amp hours (Ah): The amount of charge in a battery that will allow one amp of current to flow for one hour.  Batteries will commonly have this to quantify their power, e.g. 100Ah battery, 200Ah battery etc.
• Volts/voltage: The “pressure” of an electrical system, caused by electrons’ negative charge repelling each other. Basically, volts are the measure of force of the electric charge. The most common voltage used in van electrical systems is 12 volt direct current (DC), with most batteries used in vans being 12v batteries.
• Watts/wattage: The total power of electric charge which is calculated by multiplying amps x volts (amps x volts = watts). Solar panels will have this to quantify the maximum power that the panel can deliver at any one time.

Off Grid Solar System Components

If you’re looking to install an off grid solar system in your van, then you’ll want to know what components you’ll need for it to function smoothly. Below, we’re going to break down the components that all work together to provide power to your home on wheels.

1. Solar Panel

Solar panels are the vital component of any off grid system. Solar panels absorb the sun rays and convert it to power and electricity. This electricity can be used directly to power or charge something, or collected in a battery that is then stored and used to power appliances as needed. 

There are two types of solar panels for vans: monocrystalline solar panels and polycrystalline solar panels. Both offer the same function, although monocrystalline solar panels are more efficient and lighter, so they’re generally the preferred option for vans.

Solar panels also come in different sizes and power or wattage. You can get solar panels that are 100 watt, 200 watt or more, depending on the brand, size and quality of the panel. It can be difficult to know what size panel to get, but it heavily depends on the size of your battery and how much power you’ll need to create while off grid. For example, if you have a bigger battery bank, you’ll need more powerful solar panels to keep the batteries fully charged.

Most vans have the panels fixed to the roof, which enables them to get direct sunlight for most of the day. This means you’ll also have to take into account the size of your roof when selecting the panels that will fit your van.

2. Battery

Your van battery will generally be used to store electricity that the solar panels produce so that you can use it whenever you need. These batteries are often referred to as auxiliary or leisure batteries, because they’re in addition to your car battery and are used to power appliances or other parts of your van.

There are generally two types of batteries that are commonly used in vans: AGM and Lithium. However, lithium batteries have numerous benefits and are generally considered the most efficient option. They are much lighter, longer lasting, faster charging and have greater usable energy when compared to AGMs. However, they are much more expensive too, so this might depend on your available budget.
Either way, battery capacity is measured in amp hours (Ah) and you’ll find that you can purchase a range of capacities depending on your needs. However, choosing the right size battery is important and it all depends on how much power your appliances will draw.

3.  Charge Controller

The charge controller is effectively the middle man between the battery and solar panel. It regulates the flow of electricity from the panels and uses it to charge your batteries efficiently and safely. This is important because the controller will organise the sporadic energy coming from the panels and change it into an acceptable current for your batteries, which will keep them fully charged, without overcharging and damaging them.

There are two different types of charge controllers: PWM or MPPT. While PWM are a standard type of controller and generally a bit cheaper, MPPT chargers are more efficient and work a lot better with lithium batteries. 

There are also different size controllers and you’ll need to make sure that your controller can handle the size of your solar panels and battery effectively. Charge controllers are sized by both the maximum input voltage they can handle from the solar panels and the maximum output amps they can produce to charge your battery. When looking at the amps, aim for a charge controller of 8-10 amps for every 100w of panels. Charge controllers usually come in multiples of 10, 20 and 30 amps, so it’s always a good idea to round up. 

4. AC Inverter

As mentioned above, your battery will be storing 12v DC power. This is fine for running things like a 12v fridge, lights, 12v fans, USB or cigarette lighter outlets and anything else that runs on DC power. However, you may also have appliances that run or charge using AC power like in a house, such as a laptop, camera or blender.

The only way to convert your 12v DC power stored in your battery to AC power is by using an AC inverter. These are generally connected directly to the battery and offer a three pronged outlet like you would see in a regular house. While an inverter is not a necessity, many vanlifers like to have one for charging their laptops and using household appliances. 

There are two main types of inverters: pure sine inverters and modified sine inverters. Pure sine inverters are more efficient and supply a steady flow of power, but they are generally more expensive, so this might depend on your budget. 

You will also need to think about how powerful you need the inverter to be, which will depend on the wattage requirements for each device you want to power. The wattage represents the total amount the inverter can handle at any given time. 

As a rough guide, if you want to charge a computer and an occasional appliance, you can look for something in the 1000 watt inverter range. If you plan to run an induction stove or microwave while charging other devices, you’ll need a 2000 watt inverter or bigger. 

5. Battery Monitor

Another non-essential item that many vanlifers find useful to add to their off grid power system is a battery monitor. The charge controller does all the hard work of managing the charge rate, but you might want to know the current level of charge in your battery bank and this is where a monitor will come in.

There are a few different types of battery monitors and which one you get will depend on how much detail you want to get from your system. Cheaper ones may simply show basic battery statistics, while more expensive monitors will have an interactive screen with advanced statistics and even bluetooth connection to your phone so you can read your battery levels from anywhere.

Calculating Your Power Requirements

Now that you know all the different components of an off grid solar system for vans, you’ll want to start designing your own. However, the first thing you need to figure out is your power requirements, as this will determine the size of your battery, solar panels, charge controller and inverter. 

How powerful you need your van electrical system to be will depend heavily on what your van set up is like and the electrical demands it has. You will have to think about all the appliances and devices you need, such as a fridge, lights, water pump, mobile phone, laptop and more.

You can find out the maximum and continuous draw of most devices or products by looking at the fine print or searching specifications for each item on the web. When you find out how much power your main appliances will use or draw, then you can understand how big your van solar system needs to be.
If you’re unsure, you can seek advice from an electrician, auto electrician or van build expert, as they will be able to help you determine your power needs. You can always ask us for advice or any questions you might have, by just jumping onto our website chat or sending a Whatsapp message at 0427 495 449.

Buying Off Grid Solar Kits

It can be extremely useful to purchase off grid solar system kits, instead of having to buy some of these components individually. This offers the convenience of getting solar panels, a charge controller, battery monitor and wiring and fuses all in one kit. You’ll then only need to pair the kit with the right size battery and inverter for a complete off grid system.

Take a look at some of these solar kit options:

For the budget vanlifer:

Solar Starter Kit: 200W Panels + PWM Controller

If you’re just getting started or on a tight budget with your van build, you can begin with this 200 watt solar start kit. It includes x2 Renogy 100 watt monocrystalline solar panels, 30 amp PWM charge controller, cables, connectors and adapter kit for wiring purposes and mounting brackets.

For the full-time digital nomad: Solar Panel Premium Kit:

400W Panels + MPPT Controller

If you’re building your dream van for full-time van life, then this 400 watt premium solar kit will be perfect. It includes x4 Renogy 100 watt monocrystalline solar panels, 40 amp MPPT charge controller, battery monitor and Bluetooth module, cables, connectors and adapter kit for wiring and mounting brackets.

For the ultimate, fully off grid van set-up:

Solar Panel Premium Kit: 600W Panels + MPPT Controller

If you’re wanting to upgrade your van or bus to be fully self-sufficient and completely off grid for days or weeks at a time, this 600 watt premium solar kit is what you’ll be looking for. It includes x6 Renogy 100 watt monocrystalline solar panels, 60 amp MPPT charge controller, battery monitor and Bluetooth module, cables, connectors and adapter kit for wiring and mounting brackets.

Conclusion

Being able to live off grid in your van is one of the pure joys of vanlife. Having a well setup off grid solar system will enable you to head off anywhere you like and still be able to run and charge all your appliances and devices. We hope this guide helped you understand all the different components of your solar system and how they all work together to power your van.