Composition of solar power generation system
The application of solar system to RV is not only a charging system, but also a small energy storage system. This system is composed of solar photovoltaic modules, solar charging controller and the battery you need. The most common length of solar panels is about 1 m2, and the power varies from 100W to 400W. This solar module is used to receive sunlight and is usually placed on the roof.
Solar charging controller is actually a charging device. Now it basically uses MPPT (the full name of MPPT controller is “maximum power point tracking”) solar controller, which is an upgraded product of traditional solar charging and discharging controller. The efficiency is much higher, generally more than 95%.
At present, the output terminal of the small charging controller that can be used in the car is automatically identified, only the battery is 12V / 24V / 48V. If the battery voltage is 96V, 110V, 220V, etc., the corresponding charging controller needs to be selected.
As long as the voltage of the solar module at the input terminal is not greater than the rated input voltage of the charging controller. It must also be noted that the terminal voltage of the solar module must be 3-5v higher than the battery voltage to ensure normal operation. For example, if you use a 12V battery, the voltage of your solar module must be 17V or above to ensure normal operation. It doesn’t matter if the voltage of the solar module is higher, as long as it meets the input voltage of the charging controller.
Generally, the size of additional batteries is selected according to individual needs. It is recommended to install 400W solar panels on the RV and match 200ah batteries. On the premise of sufficient light, the best state can charge the battery by 60% – 65%. When lead-acid battery is discharged, it can generally discharge to 25% – 30%.
You may be more concerned about whether the solar panel will be effective when there are devices consuming electric energy while charging?
Theoretically, there is no problem, but it should be noted that the power of the load and the power of the loss should be matched. For example, the load power is 100W and the power of the solar panel is 200W. Normally, there will be 40% – 50% loss (mismatched loss), which can basically ensure the normal operation. If the load power is 100W and the power of the solar panel is also 100W, plus the normal loss, this cannot be guaranteed and needs to be balanced by the battery.
Precautions for installing solar panels
① Due to the uneven manufacturers of solar panels, some solar panels will be equipped with metal frames, while others will be directly laid on the roof of RV and then fixed. It is recommended that you choose solar panels with metal frames.
② Install the base. It can reverse the flow of air and drain water. Due to the excessive speed during driving, the pressure between the electric board and the air will be generated, resulting in the electric board being lifted by the wind, causing danger.
③ Solar harness. This needs attention. If you use car cables, it is very unprofessional. Considering the aging problem of wire harness, anti-aging photovoltaic lines must be used. It should be noted that the power of photovoltaic lines and solar panels should be matched.
④ Selection of solar converter. The voltage of solar energy is greater than 12V, generally 24V and 48V. It needs to be matched to 12V or other power consumers through the converter, and then charge the battery through the converter.
Maintenance of solar panels
① For most users, the installation of solar panels is not once and for all. If you often drive an RV to areas with serious haze or frequent dust, remember to always clean the surface of solar panels to prevent dust accumulation for a long time, resulting in poor power generation efficiency.
② Maintenance of harness. Check regularly to prevent the harness from aging. Generally, replace the harness every 3-5 years.
③ The service life of the solar panel itself is generally more than 15 years. The longer the time, the more obvious the power attenuation.
Conclusion: as a supplementary power supply for RV, solar charging system is not necessary. You can choose it according to your own needs.
