Even though I really hate the idea of using tech while backpacking, I’ve resigned myself to at least being able to call for emergency help. Since I’m a 110lb woman who backpacks with my daughter (and carries pretty much all of her gear too), getting the most ultralight solar panel matters. All those extra ounces add up quickly!
I’ve talked about portable solar panels before in this post – including everything you need to know about watts, how long it takes to charge devices with solar, and more. However, not all of those setups are ultralight. Here, I want to focus on the ultimate lightest solar panel solutions for backpacking.
Best Setup: Suntactics S5 + Anker Astro E1 Power Bank
At 7oz, the Suntactics 5 watt solar panel is one of the lightest that you’ll find while still being very reliable. You’ll need to pair it with a power bank though. I recommend the Anker Astro E1 Battery. At 6,800mAh capcity, it has enough juice for headlamp batteries, phones, tablets, and cameras.
- Solar panel: 7oz
- Power Bank: 4.2oz
- Total Weight: 11.2oz
- Get the solar panel here and the power bank here.
(Scroll down for the complete list and reviews of UL solar panels)
Problems with Ultralight Solar Panels
Issue #1: Need a Power Bank
Most backpacking solar panels do not come with an integrated battery. That means you can only charge devices directly using the solar panel – such as by attaching the solar panel to your backpack as you trek.
Direct charging does mean you get more efficiency because power isn’t lost through cables and in conversion. But you won’t be able to store power:
- You will only be able to charge devices during the day.
- There will be no way to charge devices on cloudy days.
- You may even need a charge controller for direct charging, which means extra weight.
The solution to this is simply to bring a power bank with you. Use the solar panel to charge the power bank. Then you charge your devices with the power bank (which can be done at night, on cloudy days, etc.).
But this means extra weight. Thus, you’ll need to also shop for an ultralight power bank, not just a lightweight solar panel. As recommended above, the Anker Astro battery is probably your best bet. It is just 4.4oz for 6,800mAh capacity. Get it here. Or read more about the Best Lightweight Power Banks for Backpacking.
There is also the option to choose a solar panel with an integrated battery. These solar panels will weigh more, but it might come out lighter because you don’t need a separate power bank. The BioLite solar panel reviewed below, for example, has an integrated battery and weighs 13.8oz. That’s pretty lightweight!
#2: Inadequate Wattage
More wattage equals more weight. As a general rule, you will need at least 10 watts in order to charge phones and other small devices while backpacking. Anything less than 10 watts means it will take forever to charge a battery – even in ideal conditions!
Also note that some devices won’t charge at low power. Nokia phones, for example, require 120mAh to start charging. If the low-watt solar panel can’t produce this amount, then the phone won’t charge at all.
Even if you think 10 watts is adequate, remember that the wattage is listed for ideal conditions. When you factor in losses from clouds, conversion, loss due to cables, etc, you get much less power. Thus, a low-wattage power bank might end up being dead weight.
Issue #3: Don’t Forget the Weight of Cables
It’s worth noting that most manufacturers only list the weight for their solar panels. This weight does NOT include accessories like cables, 12volt-to-USB adapters, or charge controllers. These can add a few ounces to the setup.
The Bottom Line?
Bringing along a solar charge is going to add weight to your setup. There’s no way around that. The lighter you go, the less functional your setup is going to be. So be realistic about how much power you need and get a setup which can provide this. Otherwise, you’ll end up with an expensive toy in your pack which doesn’t actually power your devices.
Tips for Keeping the Weight of Your Solar Setup Down
Luckily, solar panels are getting a lot more efficient and better at doing their job. They are also getitng a lot lighter. You don’t even have to spend a fortune to get a good lightweight solar panel anymore. The BioLite 5+ solar panel, for example, is really affordable.
Ultimately though, the only way to reduce your solar setup weight is to reduce your power needs.
The less you use your devices, the smaller of a solar panel you can get away with. Normally you shouldn’t get less than a 10 watt solar panel, and that’s in ideal conditions. To get away with a low watt solar panel, you’ll need to:
- Keep your phone turned off or in flight mode (if you are using it for photos)
- Download LUX to control screen background
- Use Greenify app to turn off background apps without having to uninstall
- Keep phone GPS off until you need it
- If you listen to music on your phone, use earbuds instead of the speakers
- Keep devices at “room temperature” Sleep with them on cold nights if you must.
- Be stingy about taking photos and videos.
- Set up camp on time so you don’t have to rely on headlamps at night.
Best Ultralight Solar Panel Solutions
1. Powerfilm 10 watt – No Battery (12oz)
In discussions about the best ultralight solar panel, this one always comes up. The reason is because it can charge even in cloudy conditions. It outperforms other solar panels in this aspect, even if it does weigh a bit more.
Note that the panel gives a 12v output. So you will need a 12v to USB adapter (included). This adds weight to the setup, making it around 15oz instead of 12oz. If you are charging a device directly, you’ll also probably want to get a charge controller.
- Charges in cloudy conditions
- 10 watts
- Light for wattage and size
- Folded dimensions are 3.5×10.5×1.3”
- Unfolded it is 21×23.7”
- No integrated battery
- No auto reset
- RA-2 adapter adds weight
- Need charge controller for directly charging devices
2. Suntactics S5 – No Battery (7oz)
Suntactics is one of the best known brands for ultralight solar panels. They have been used by many backpackers and advertise the fact that they’ve “traveled on all the American trails for over 8 years now.”
Most users are in love with this solar panel as it is very reliable. You won’t want to use it for directly charging though, at least without a charge controller. Instead, pair it with a power bank. If paired with the Anker Astro power bank (4.4oz) the total setup is just 11.4oz.
- Designed for backpacking
- Very durable
- 5 watts
- Wattage is actually accurate
- Closed size: 6×6”
- Open size: 6×11”
- Auto reset
- No integrated battery
- Need charge controller for direct charging
- Doesn’t actually give 1amp current
- Plastic laminate hinge is crappy
3. BLAVOR Qi Solar Battery Bank (8.5oz)
For trips of up to 1 week, you might not even need a solar panel. A 10,000mAh battery pack will probably keep your gadgets going.
This battery bank by BLAVOR packs that much capacity. And, just in case you need more, it has a small solar panel on it. Of course, it will take forever to refill the battery bank with the tiny solar panel (56 hours in decent sunlight!). However, you can charge it in town when refueling and use the solar panel charging for emergencies.
- Just 8.5oz
- 10,000mAh integrated battery
- 1 amps
- Wireless charging
- Small and compact (5.6×2.9×07”)
- Refill battery in 6 hours via wall outlet
- Very affordable
- Tiny solar panel
- Takes 56 hours to refill battery bank with solar!
4. BioLite Solar Panel 5 – Integrated Battery (13.8oz)
The BioLite is a complete power solution for backpacking. At 13.8oz (which includes the battery weight), it is truly an ultralight solar panel.
As expected from such a lightweight solar panel, it will take forever to charge devices. The battery capacity is also pretty low. So, even if you precharge the battery before leaving for your hike, you still risk running out of power. However, it is very affordable so worth considering if you are on a budget.
- 13.8oz total weight
- 5 watts
- Integrated battery
- Clips to a backpack
- Charge strength indicator
- Battery only has 2200mAh capacity
- No auto reset!
- Not flexible
- Approximately 10x8x1”
5. Solar Paper by Yolk Station – No Battery (4.8oz.)
This solar panel has gotten mixed reviews and it is a bit pricy, but it is also one of the lightest weight solar panels available.
Each 5 watt panel weighs just 4.8oz, and you can connect as many panels you want. It also has nice features like auto reset, LCD amp meter, and an IP64 rating. You’ll have to pair with an external battery bank if you want to store power, which does mean extra weight.
Note that this solar panel doesn’t have the auto-reset feature, which can be a pain if you need to use it in cloudy weather. That’s why this solar panel doesn’t make the top pick, despite being the lightest weight solar panel.
- 5 watts; can add multiple panels
- Only 0.4 inches thick
- Two connections
- Folds to 3.5×7.5”
- Auto reset
- Just 1 amp
- No integrated battery
- No straps
- Overheats easily
Do you use a solar panel when backpacking? Which one? Let us know in the comments.
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