Solar power system for a panel van in the desert

ExSolar recently installed a system for a unique project requiring mobile energy…
This panel van belongs to Gaynor Schoeman who is a famous desert walker who’s plan is to cross the desert in this vehicle. She required the van to be reliant on alternative power sources in order for her to be self-sufficient with regard to power.

The project planning started in December 2013 where discussions of fitting flexible panels to the vehicle where had, due to their length and efficiency a 150W panel was fitted on a Roof Rack system on top of the vehicle.
This took some engineering to ensure that the panel would not take a pounding on dirt roads and desert dunes, a rubber shock system was installed by the ExSolar team to prevent the system from damage.
This system allows Gaynor to have a second battery to run her Fridge, LED lights and inverter for a Laptop and other small appliances requiring 230V AC.
A Cyrix 12/24v-120A Battery Combiner was fitted between the vehicle battery and the Lead Crystal Solar Battery.

This unit allows the solar battery to be charged by the vehicle’s alternator whilst driving.
When the vehicle is stationary and not charging via Solar, at night for example, only the extra solar battery will be discharged and will not discharge the vehicle’s main battery, thus allowing one to start ones vehicle even if the extra battery runs flat for what ever reason.
This is the function of the Battery combiner, allowing discharge of the Lead Crystal Solar battery ONLY.
This Victron Energy Cyrix system has an added BOOST! START Button function.

Should ones main engine battery run flat for whatever reason and through no fault of the Solar system, one would be able to connect the solar backup battery through to the main battery for 30 seconds. This allows one to start the dead vehicle by using the extra battery.

​The main panel with all equipment installed.
The main board was installed in a position that allowed ease of access and still allowing room for packing the vehicle in an efficient manner.

The system has Solar fusing, Battery fusing as well as a remote switch running from the Victron 12V 350W inverter which cuts out the stand-by power of the inverter.
The Victron inverter has a protection built in so that if two powerful devices are plugged in, the system will cut out.
The solar panel and charging system:

The solar panels  charge through the Victron’s  15Amp 70V MPPT Controller (maximum power point tracker).
This MPPT technology has two advantages. Firstly it does not, when the battery is full, switch off the panel and allow the battery to discharge, thus cycling the battery unnecessarily such as the old fashioned PWM charging. It does a bulk charge then slows the rate of charge down and then floats the battery even if the load should increase during the day.
Secondly, the panel voltage is much higher than the battery voltage. MPPT technology does not just cut off the voltage to meet the battery’s voltage, it inserts the extra voltage in the form of amps instead thus giving 30% more charge to the batteries compared to old technologies.

Ready to go solar system!