There’s nothing worse than running out of 12V power while you’re out exploring the best parts of our glorious country. Just last week I lost an entire fridge-load of meat after the battery went flat and the fridge switched off; of course, I didn’t realise until it was too late. The Mrs did mention something about the 12V shower not working properly but I was too busy feeding the fish all my bait to take that too seriously. It wasn’t until the beer went warm that I realised we had a serious problem on our hands!
With that in mind, I thought it was about time to dive deep into the wonderful world of solar power.
If you haven’t had much to do with solar over the last few years, it can be pretty easy to get overwhelmed with all the technical jargon, not to mention the number of different options available these days.
Trying to make sense of it all is near-on impossible, so I’ve called in the big guns and got Roy Ding from Arizon International on the blower. This bloke is a dead-set guru with this sort of thing, and after having dirty thoughts about fitting a big, you-beaut solar system on to my own camper trailer before setting off for the big lap, I thought it was the perfect time to get the low-down on anything and everything to do with tailoring the ultimate solar system for your camper trailer.
So let’s see what he had to say...
SOLID VS. FLEXIBLE SOLAR PANELS
When it comes to permanent solar systems, the debate between solid solar panels and the flexible options is never ending. Ding reckons the main differences between these two designs is found in the two materials used in their construction.
“Tempered glass solar panels (solid) generally have a much longer lifespan, with most coming standard with a 10 year product warranty,” he said.
According to Ding, the glass is robust and thermally stable so it can’t be easily scratched and it doesn’t deform under heat.
“These panels come with aluminium frames for easy mounting and an air gap under the panel will keep it cool and efficient,” he said. “The only downside is they are a bit heavier than a flexible panel option, which isn’t always ideal for some applications.”
Flexible panels have a shorter design life in comparison, with warranty periods usually only active for one to two years.
“The plastic surface tends to get scratched or gouged by low hanging trees when mounted on caravan roof tops, which means the solar cells themselves are susceptible to damage,” he said.
Constant, intensive heat on the roof also accelerates the ageing process of plastic.
“You’ll find the top of these panels tends to warp and create little cups on the surface, which collects dust and reduces the solar cells efficiency.”
If the weight is manageable, Ding recommends glass panels for a reliable, long lasting system.
“It will be a system that is easy to install, long lasting and almost maintenance free other than periodic cleaning.”
WHAT SOLAR CHARGER SHOULD I BUY?
According to Ding, a Maximum Power Point Tracking (MPPT) charger is best for most camper trailer applications.
“Comparing to a Pulse Width Modulation (PWM) charger, an MPPT charger will provide an average of 20 per cent more amperage while cost at least $100 more.”
This may seem pricey on a small 100-200W system, where the difference in regulator type exceeds the cost of an extra panel but Ding says there are other benefits.
“MPPT regulators are not only more efficient but they’re usually higher quality in general making them more reliable for touring applications. Plus, MPPT can convert voltage between the solar system and battery bank, as long as the voltage of the solar system is higher than the battery bank.”
This means you can daisy chain your panels (connect them in a series) saving you a lot of work on wiring and allows the system to run on the lower amp and higher voltage, which is much more efficient.
“Don’t worry, you won’t be losing any amps either – the regulator will drop the voltage and increase the amp again when it’s charging the battery bank,” he said.
Ding says MPPT regulators come with all different models and features. Some have display screens which provide useful information such as charging amps. Others come with the minimal user interface and no screen, but they can be extremely versatile once a Bluetooth dongle is plugged in and the device is connected to your mobile phone.
“I strongly recommend using a regulator that provides you a live amp reading, which lets you know how the solar system is performing and what you could expect from it. It’s a great tool for troubleshooting or diagnosis, too.”
PORTABLE VS. FIXED PANELS
You’ll find fixed solar panels are a no-fuss option with next to no setup required. They can also help insulate your caravan or camper from the sun’s heat. The down side being they can be a bit heavy for some pop-top models, and they rely on being parked in the sun to be efficient.
The benefit of a portable solar panel is you can park in the shade and set the panels up a few metres away in full sunlight for maximum efficiency. The drawback being you’ve got to set it up manually and there’s always the risk of theft. In short, portable panels are usually more efficient as they’re able to be tweaked into the perfect position, but fixed panels usually make up for this by including more solar power into the system.
If the idea of free power sounds good to you, then a well set up solar system will definitely tickle your fancy. The key is to plan your ultimate 12V system, before working out exactly what you’ll require from your solar system to cater for your entire 12V system.
One thing’s for sure; get it right and powering all of those fancy camper trailer accessories will become an absolute breeze. Oh, and make sure you allow for a few added electrical accessories down the track, too; chances are you’ll want to add some fancy new gadgets in down the track!
Check out the full feature in issue #111 of Camper Trailer Australia magazine. Subscribe today for all the latest camper trailer news, reviews and travel inspiration.