You might've guessed how solar battery chargers work. The sun is a very powerful thing, isn't it? It helps us see and keeps us warm despite being roughly 92,955,807 miles away from us. The earth continually receives 173,000 terawatts from the sun, which is far more energy than even the best car battery chargers require.
It's good to know the potential is there - we just need to harness it. Luckily, solar power is now the cheapest form of energy source. Solar panels are also becoming increasingly effective, demonstrated by off-grid solar homes and solar battery chargers too.
While a production solar-powered car may not be a reality yet, solar battery chargers can harness some of the power to stop your car's battery from going flat. Solar battery chargers are a clever way to top up your battery without having to plug it into the mains or have them charged up all the time. This makes them ideal for those who may require the benefits of a good trickle charger, but don't have access to a garage.
The best solar battery chargers at a glance:
Editor's pick: AA 12V Car Solar Battery Charger - buy from Amazon.
Best to put on a dashboard: Eco-Warrior 12V Portable Battery Charger - buy from Amazon.
Best for trickle charging: Streetwize 12V Solar Battery Charger - buy from MachineMart.
Remember to also consider regular car battery chargers too, and what's most suitable for your needs. There are also jump starter power packs for when batteries have already dropped below a critical point.
The best solar battery chargers
Editor's pick
Via AAThe AA 12V Solar Battery Charger is our top pick for solar car battery chargers because of how effective it is. Not only can it attach to your 12V socket and the battery directly, but it can also plug into your car's OBD port to provide power even when the ignition is turned off. And at 4.8-watts, it should be strong enough to restart a dead battery too.
Pros
- Works without an ignition source
- Includes several connection ports
Cons
- Not overly stylish, if that matters
Best to fit to a dashboard
Via Eco WarriorBoasting a very impressive 10-watts and designed for more than just cars (boats and ATVs can be charged too), this solar car battery charger is a good way of keeping your battery charged. While it can only connect via a 12V socket or battery cables, the soft, padded rear makes it perfect for use of your dashboard without the fear of scratches occurring.
Pros
- Good power for the price
- Soft back means no scratches to your dash
Cons
- No OBD connector
Best solar trickle charger
Via Streetwizewww.machinemart.co.uk
Designed to be used over a long period of time, this battery charger is ideal if you have a car you rarely use (like a delicate classic car) but don't want the hassle of having to jump-start it on the occasion you do use it. With 6W, it is ideal as a trickle charger.
Trickle chargers tend to be a little more gentle than a traditional battery charger, meaning your battery won't be overloaded whilst you're not using your vehicle.
Pros
- Keeps your battery topped up with ease
- Good quality product
Cons
- Eco-Worthy is more powerful
Most versatile battery charger
Via CTEKThe CTEK CS FREE is a portable battery charger that acts a conditioner, jump starter, and power bank. On its own, it's not solar powered, but there is a powerful 50-watt CTEK solar panel to which it can be connected and recharged. Having a portable, versatile battery charger being recharged by solar sounds like a brilliant all-round solution. It is, but the drawback is it's a very expensive option.
Pros
- Reduces harmful emissions
- Battery charger, jump starter and power bank
Cons
- Not fully solar powered
Best solar charger for motorcycles
Via Oxford It's not just car batteries that can enjoy solar charging. Vehicles on two wheels can too, or even those with no wheels. The Solariser is a 12V solar charger for use on motorcycles, ATVs, and jet skis. It'll connect direct to a battery or plug in via the 12V socket. There is a three-metre extension lead available, if you need it.
Just remember, the ignition will need to be left on for the Solariser to work if using the 12V socket. It isn't just us recommending the Solariser either, our compadres over at MCN recommend it too.
Pros
- Weatherproof
- Direct and 12V charging options
- Extension lead available
Cons
- More powerful options available
What you need to know about solar car battery chargers
What features should I look for?
Unlike even budget battery chargers, solar-powered ones can vary a little in power. The main thing to look for is what wattage the solar panel offers. Lower wattage is fine for trickle charging and maintaining and also cost less. Higher wattage models charge faster, but the panel will be bigger and cost more. Also, try to find a solar car battery charger that has an OBD option. While not every car comes with an OBD socket, most modern ones do and it'll make trickle charging a lot easier.
How do I install a solar battery charger?
If you're connecting your solar car battery charger to your OBD or 12V socket then the best place to place the panel is on the dashboard. It's also important to remember that not some 12V sockets will need to have the ignition turned on. If left off, even if your solar car battery charger is plugged in and working, it won't be charging your battery. Smart battery chargers can differ because they can effectively maintain your car's battery whilst you're not using it.
If you are connecting the solar car battery charger to your car's battery, a stop/start battery or otherwise, then you'll need to leave your bonnet catch open for the cables. Or if you have a BMW with the battery mounted in the boot, you'll need to leave that open.
Ryan Gilmore is the Deputy Autos and Tools Editor for CAR, specialising in car cleaning and hand tools. With an MA in Automotive Journalism, when he's not testing buckets he can be found looking at old Porsches.