Go-to-guide to power management

Understanding consumption

Many of us love caravanning for its simplicity; the laid-back and fuss-free lifestyle it offers in contrast to the hustle and bustle of our everyday lives. So we want our trips to be as relaxed and hassle-free as possible. From hitching up our caravan to setting up camp, we want everything to work the way it should. We want to know that the beer is cold, the meat is fresh and the water tanks are full. We don’t want to have to worry about any of it, but we also want to make sure we are not over-using power. 

The best way to do that is to set up your RV’s power system properly from the start, so you can set and forget it. But it’s no wonder many caravanners find RV electrical systems complicated. 

Throw open the front boot of an old van and, chances are, you’ll be met with an eye-watering array of devices, hardware and wires screwed into a piece of MDF, connecting to and from the house battery, with no way to determine what’s what. 

Here we help break down the main points that new or potential caravanners need to know in order to maximise time, safety and comfort in the wide variety of often hostile and, at best, tough environments.

In order to decide on the best type of system to suit your needs, you need to understand how you and your caravan will consume power while on the road. The length of time you plan to spend in your caravan, the destinations to which you plan to travel and where you’ll stay when you get there — not to mention what appliances you plan to power — will dictate the type of power setup you need.

When designing your electrical system, due consideration must be given to your travelling destination and the period of time you’ll spend in the RV — even more so if you’re travelling off-grid. That way you can figure out what needs to be included into your system to keep your gizmos going. 

WHAT TYPE OF CAMPER ARE YOU?

The humble 12V battery is the lifeblood of your caravan when you’re away from home, the demand for its service depends on your individual circumstances. There really is no typical power setup, as the number of accessories in use and the style of camping changes dramatically between different types of travellers. 

Are you the type who likes to park up at a bush camp and just enjoy nature and your surroundings, with only the basics and no high-usage devices or appliances? 

Do you plan to camp off grid for long periods of time without using your car (which can recharge your batteries) and with a large range of power-hungry appliances such as a toaster, washing machine, hair-dryer, a coffee machine, air-conditioning system and so on? 

Will you mainly stay on powered sites in caravan parks? In this case, the seemingly endless supply of 240V mains power plugged straight into your van will take care of the majority of your power needs.

Are you planning to stay in a combination of caravan parks and bush camps for a few days at a time, using just the RV basics such as your fridge, LED lights, and TV?

Or maybe you hope to do a combination of these trips throughout the year.


HIGH-DRAW AND LOW-DRAW APPLIANCES

Once you’ve figured out what type of camping you’re likely to be doing in your van, you need to do a stocktake of the number and types of appliances you plan 

to run at camp.

Most caravans come with standard items including LED lights (inside and out), a flatscreen TV or two, a fridge, cooktop, oven, microwave shower, toilet, air-conditioner and even a washing machine. But the list of appliances you could install in your van is endless — coffee machines, hair dryers, and inverters are not unheard of. All these items come at a price — and that is the amount of power they consume. 

While LED lights and TVs are relatively low-draw (but still need to be accounted for), other items such as toasters, coffee machines, microwaves, hair dryers, 

air-conditioners and washing machines are extremely high-draw, consume a huge amount of electricity and shouldn’t be used on battery power alone. Basically, any appliance with a heating element can be put in the ‘high-draw’ category.

While fridges would usually be considered a high-draw item, many caravan fridges are designed to work on gas when not connected to 240V mains power, and will not impact greatly on your 12V power consumption.


HOW IS POWER CONSUMPTION MEASURED?

Once you’ve figured out what type of camper you are, you need to start looking at how much power, on average, you’ll consume in a day. All items in a caravan consume power and, as a caravan owner, you need to be aware of how much you’re using and how much capacity you have. 

Once your system is set up, you can let your battery monitor do the work for you (more on that later) but, to give you an idea of how big your setup needs to be, you’ll need to get out the calculator.


WHAT DOES A BATTERY MONITOR DO?

A battery monitor can be likened to a fuel gauge for your RV — it should tell you at a glance, how much ‘fuel’ or battery power you have left. But as technology has improved, so too have battery monitors, Fully-integrated monitors now combine a 12V battery monitor (for multiple battery types), a water tank monitor, a water pump control, a battery isolation switch, a clock and a nightlight. 

At a minimum, a battery monitor should display your battery’s volts and amps, plus charge and discharge status. Measuring volts, however, is just one indicator of battery power, much like measuring kilometres per hour in a car. 

This will tell you how fast you’re going, but not how long you’ll be able to maintain a particular speed or if you have fuel in the tank to run it. Newer devices count the energy put into the battery via the charger and the energy taken out during use and map these against the volts and amps available combined with time and temperature, giving you a complete picture of your battery’s capability.

These readings will tell you the amount of battery capacity left as a percentage, and also how much time is remaining at your current electrical load, enabling you to see, at a glance, whether you’ve got enough battery power left to keep the beer cold until the evening. How’s that for stress-free travel?

Power supply has the potential to make or break your holiday. There are several individual and related power sources you may need to consider when setting up your rig, making it one of the most complicated parts of caravanning.

Most of your van’s appliances (such as lights, TV, etc) will run on either (or both) 240V mains power and 12V battery power. Others, such as a cooktop, barbecue and heater will probably require gas, while a generator or space heater may use diesel.

All these power sources need to be understood and considered to ensure a successful camping trip — from when and where you’ll access 240V power if needed and how you’ll power your 12V batteries, to where and how you’ll source and carry your additional fuels of gas, diesel and/or fuel.