This is a four part mini-series that will review the main types of battery chargers: AC-to-DC, DC-to-DC, and Solar. This isn’t a product review or a scholarly journal...it’s an overview intended to help you to identify the best charging system for your application.
For the purpose of this synopsis, we’re going to look at 12v systems used in a mobile application, such as camping.
In the camping world, solar is the sexy counterpart to the indiscriminant AC-to-DC or DC-to-DC charging systems. A good solar system says something about you and your style, because someone who invests in a solar setup probably values the environment, technology, and wide open spaces. You’re somebody who likes to get out for long periods of time or with some pretty cool gadgets...or both.
For the reasons mentioned above, solar chargers have a stigma; they’re cool. They represent a freedom that can only be achieved by being untethered to the modern world. (In the developing world they may be the catalyst for becoming tethered to the modern world. But as I said, we’re approaching this from a mobile, recreational application.)
With that in mind, lets review the PROs of a Solar Charger system:
- Once the system is installed, the energy is free.
- In the right conditions, with a properly sized setup, you’ll be able to be self-sufficient indefinitely. If you’re a fulltime overlander, or someone who likes to go on long-term, off-grid trips, this is the only point you need. Mic drop. End of discussion.
Now, while the freedom that solar can offer cannot be overstated, there are CONs that require careful consideration as well:
- Solar systems are the most expensive charging solution, from a capital purchase perspective.
- Not all areas are conducive to solar regeneration. If you’re camping in a dense forest, you’re not going to be able to capture a lot of solar energy. If you’re in a climate that is overcast for a portion of just about everyday, you’ll be missing out on at least a portion of your system’s potential. Bottomline, unless you only camp in ideal conditions (and many people do...lookin’ at you southwestern states), a solar system is susceptible to environmental impacts. In most cases, this can be overcome by hedging your bets and investing in an alternative charging source.
If you’ve decided that solar regeneration is a worthy venture to embark on, Congratulations! To set up your mobile site with solar, you’ll have some choices to make:
- How much recharge capacity do I need?
- Do I want to affix solar panels on my roof or do I want mobile panels?
- Do I have storage space in my rig for mobile panels?
- Do I have enough available roof space for fixed panels?
- Will this be my primary power source or will this be paired with another charging system?
By answering these questions, you should be able to zero in on the type and size of solar system you’ll want to invest in.
In addition to the panels themselves, to be fully operational you’ll need a solar charge controller. There are two options Maximum Power Point Tracking (MPPT) and Pulse Width Modulation(PWM). In general MPPT’s controllers are the preferred option, since they are more efficient, especially as you increase the watts/size of your solar panels. With that said for a single 100watt panel a PWM controller will work just as well and save you a few bucks up front.
If you’re not in ideal conditions and find that you’ll need an alternative power supply for those days you're camping under a tree canopy, you’ll want to explore an MPPT that also is attached to an AC-to-DC or DC-to-DC charger.
Once the system is set up, you’ll be free to roam and maintain your battery indefinitely.
Thanks for checking in. Next week we’ll wrap up this series by exploring the age old question, ‘Capacity or Generation?’ Don’t miss it.