How much solar power for my campervan?

2020-09-21

Buying solar panels by searching at on-line shop is the easy method, you can get the various models from small 45W to standard 360W. We all know solar panels is able to be the supplementary power source. But how much power do you need to keep campver van be charged up? Is it possible to power a refrigerator 24*7 on a solar panel? 

With some simple calculations you will easily find out the installation which meets to your power needs. 

The solar panel system working:

Solar panel are composed by the solar cells made of silicon. Solar panel creates an electric current as soon as it receive the sunlights. With the sunlights energy going the electron will start running to one direction, which creates the current, like the battery it has both a positive and a negative layer. 

A solar charge controller receives the current and the voltage from solar panel and converter it to be the stable and regulated power then delivery it to your battery. The solar charger is also named as the "solar controller" as it also control the charging to prevent the batteries from being overcharged. And here is the role of each parts act in the system:

Solar panel: Create irregular and a mass of current and voltage. 

Solar charge controller: Convert the irregular current and voltage to be a regulated current and voltage, use a special way to delivery feed to battery. 

Battery: Store all the energy from the solar charge controller.

--Let's start from the fridge energy needs:

How many solar panels does a fridge need?(Total off grid, no AC-DC charging, no alternator-DC charging)
Generally fridge works all day long but only make refrigeration in around 7 hours in 24 hours. The 12V fridge for camper van is from 55 watts to 70 watts, that means there must be with 500Wh per day for fridge. 

Here is the some different solar panels models and the corresponding working hours for 500Wh power generation(Say in 2 hours fully-power working);

*Quantity=500Wh/2hrs/each solar panel watt

Solid Glass:

Flexible Solar Panel:

The similar calculation for the appliances in your camper van. For example:

* If you have AC-DC charger, calculate the energy it creates and remove it from the calculation result.

For example: An 40amp AC-DC charger, average 3 hours charging. 

12V*40Amp*3hrs=1440Wh

*If you install an DC-DC on board charger, calculate the energy it creates and remove itr from the calculation result.

For example: An 30Amp DC-DC charger, average 1.5 hours driving trip.

12V*30Amp*1.5hrs=540Wh

The energy supplement from solar: 2912Wh-1440Wh-540Wh=932Wh

In the condition of workable available sunlight at 3 hours. Calculate according to formula:

Quantity=932Wh/3hrs/each solar panel watt

100W solar panels: 3pcs

150W solar panels: 2pcs

Conclusion
Popsail is offering 100W solid solar panel and flexible solar panel for camper van. Taking the time to do some math on the capacity of your solar panels and the needs of your camper van appliances and devices will ensure you have an effective solar installation that meets all your solar needs.