If you have obtained the necessary parts such as solar panels, charge controllers and electrical cables with plugs and installation material from a specialist shop, there is nothing wrong with building solar power systems by yourself. However, you should take a few things into account so that nothing goes wrong.
If you have heaved your panels onto the roof, an aluminum spoiler solution will help you to attach the panels to the roof. This means that the modules are ventilated and cannot overheat in strong sunlight. Although many caravanners and motorhome owners are afraid of gluing, this is the preferred method among experts to install something on the roof. The only hole you have is the roof duct for the cable and therefore only one spot that you have to seal. Make sure, however, that the cable is routed backwards and not in the direction of travel. This avoids the risk of rainwater being forced through the roof duct.
Once the lead wire has then been installed in the vehicle, all you need to do is connect the charge controller to the 12v lithium battery, which should be placed as close to the battery as possible.
Tip for building your own:
1. Pay attention to clean processing.
2. As soon as you use an adhesive, the roof must be completely free of grease and the surface must be slightly roughened.
3. Give the glue some space between the parts to be attached. When drying, it usually swells up a bit and needs space.
- Since the glue forms a network structure, you should give it enough time to harden.
Other components of a solar system
The electricity in your camping vehicle comes from one or more RV batteries. In mobile homes and vans there are usually two or three – the starter battery in the engine compartment and one or two consumer batteries (on-board batteries). There is no starter battery in caravans, only the on-board batteries are used here. You can find all the details in the article The right on-board battery in the motorhome.
Batteries in the mobile home
The batteries are charged by the alternator while driving. Of course, this is not the case when the vehicle is stationary, which is why you need the solar panel generator as an energy generator. If you also want to operate 230 V devices (e.g. hair dryer, coffee machine, computer), you also need an inverter that transforms the 12 volt on-board voltage to 230 volts.
Other components of a solar system
The electricity in your camping vehicle comes from one or more batteries. In mobile homes and vans there are usually two or three – the starter battery in the engine compartment and one or two consumer batteries (on-board batteries). There is no starter battery in caravans, only the on-board battery(ies) are used here. You can find all the details in the article The right on-board battery in the motorhome.
Batteries in the mobile home
The batteries are charged by the alternator while driving. Of course, this is not the case when the vehicle is stationary, which is why you need the solar system as an energy generator. If you also want to operate 230 V devices (e.g. hair dryer, coffee machine, computer), you also need an 3000w power inverter that transforms the 12 volt on-board voltage to 230 volts.
Determine power requirements
In order to dimension your solar system correctly, you must first take a look at your consumers, which are to be operated independently. For example:
- Heating
- Refrigerator/cool box
- Laptop(s)
- Tablet(s)
- Smartphone(s)
- Internet router
- TV/radio
- Speaker
- Water pumps
- Coffee maker/kettle etc.
Once you have identified these, you should determine as precisely as possible how much voltage (volts) they require, how many watts they consume and how long each of them runs per day. This results in the required power, energy and electrical charge. If you add up the individual charges of the devices, you get the amount you need per day. From this you can derive which batteries you need and how big your solar panels should be.
In order to finally test the required storage capacity of the battery, you still need to know how many days you want to stand autonomously. Or to put it another way: How many days of bad weather (when the battery is not charged) do you want to be able to bridge?
Solar modules have various parameters that are relevant to your purchase decision:
1. The maximum power Pmax in watts. You can find this number on every solar panel.
2. The voltage in volts.
3. The maximum current in amperes. The panels should provide enough power in one day to fully recharge your batteries. So if you need about 55 Ah a day and want to get by with it for three days, your system has to deliver 165 Ah a day.
12 volts vs 230 volts
Many technical devices that we use in our everyday life run on 230 V. However, they often have a power pack that transforms the electrical voltage from 230 V down to 24, 12 V or even less. An inverter is used to operate 230 V devices in the mobile home.
If you now connect a 230 V device with a power pack, the voltage is transformed from 12 V to 230 V by the inverter and back to 12 V by the power pack. Energy is lost and converted into heat. Classic “electricity wasters” such as hair dryers, mini ovens or coffee machines can also put a lot of strain on the batteries and drain them quickly. It is more efficient to use 12 V devices or to work with an appropriate adapter. However, some devices such as hair dryers or mini ovens are not available with 12 volts. Here you either have to do without the devices or, as with the oven, fall back on gas-powered models.
If you are still considering purchasing an inverter, it makes sense to tend towards a sine wave inverter. This gives you the same power quality that comes out of your socket at home. There are sensitive consumers such as televisions or laptops that react to irregularities in the power supply with disturbances.
