POWER SUPPLY IN THE FOUR-WHEEL CAMPER

Now it's going to be electric - it's about the power supply for our off-road camper. Our long-distance camper van should have a self-sufficient, simple and reliable power supply. Self-sufficiency was particularly important to me because we only want to use shore power as a backup in bad weather. As a result, the focus when selecting the components is very different, such as in a camper van, which has a lot of shore power on camping sites and pitches. Self-sufficient power supply in the overland camper

We planned this 4x4 camper as our home, to be where we like it indefinitely. Driving it every day is just as little a part of the plan as regular visits to campsites and RV parking spaces. The power supply was designed in such a way that it works independently and "driving" or "shore power" is more of an option. The hut simply has to work all over the world.

Since we don't like cold or wet weather, we will try to stay in sunny areas most of the time - which therefore makes an additional power generator unnecessary. Should we later want to spend the winter at the North Cape, this would also be possible with small optimizations, such as more powerful chargers and a corresponding generator. But hopefully, it doesn't come to that.

planning phase

Online Portal of Victron Energy

At the beginning of such a project, there is a needs assessment. Since I've been running the Victron Venus GX in the Vario since 2018, I only had to read off the power consumption of the individual months and had a result so quickly. I should plan 90-100kWh per month. Although the power supply will be more economical with other inverters, two electric water heaters will compensate for this. We bought the 230V fridge first and spent many weeks in the hall with one electricity cost meter let it run in order to gain initial experience.

With my Vario, the batteries were empty after 1.5 days in the shade. During longer periods of rain in Portugal, one day was often not enough. With twice the capacity, 3 days of full self-sufficiency should be possible. In addition, a little more PV power (solar system) to be able to cover the basic requirement even when the sun is low. Assuming 3kWh daily consumption, 1230Wp are required for this in southern Spain. Since you can't always count on a cloudless sky, it can also be a little more.

Summary: For the 3kWh daily energy requirement, my power supply should be designed as follows:

• at least 10kWh battery storage (12V 800Ah or 24V 400Ah)

• at least 1300Wp PV power

Note redundancy

Independence, flexibility and high operational reliability were very important to me. In principle, all-in-one combination devices are ruled out. If such a device were to break down, the entire system would fail! The choice of high-quality devices goes without saying, but even then the failure of a single device, for example, due to water damage, can endanger the power supply, which is why all important devices are duplicated.

Contrary to what many of you might suspect, I made a conscious decision against the Victron Energy MultiPlus inverter/charger combo. There is no doubt that they are great devices, but only in their area of ​​application. What good is a PowerAssist if I don't want to use shore power? The lack of shore power stabilization directs fluctuating mains voltages into the vehicle or does not even switch on if the mains voltage is too bad. In countries with 110V, the 230V MultiPlus does not work either. Here I wanted to implement a solution that saves on additional mains voltage converters and stabilizers and is also cheaper and lighter.