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Solar Panel Update 2017, before you buy – what may help you about making the best choice.

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    • Solar Panel Update 2017, before you buy – what may help you about making the best choice.

      The challenges of charging a smartphone on the trail

      Obviously you need a lot of surface area to get a decent output; in the United Kingdom with a lot of cloud it just doesn’t really work the outputs are just too small unless your panels are huge. Here in the USA cloudy and Green tunnels are less of an issue as yet again a major mile stone of engineering has once again made older panels obsolete manufactured prior to 2015. The latest changes including moving the tiny wire lines behind the collector. When you look at the new panels you just see a dark purple and no silver. To help you understand the importance of this, right now it’s January in Pennsylvania, 32° cold and on a day that was so cloudy I could not see the sun. Using an app to help me point the Anker 20 watt panel at 11:30am and by1 pm, the smaller Anker battery was from zero to 50% which equals 1 phone charge and accessory charge on a very small old Anker brick.

      My personal charging plan of attack is to carry a large wattage panel, a 21 watt version, and only pull it out when stopping for water or lunch breaks. The 21 watt panel, even with less than perfect light conditions can produce 4-5 watts of power which is the same as a wall charger. If you have excellent sun, you can actually charge your iPhone or android faster than if you were at home (up to 7.5 watts). So I basically try to hit it hard and fast and be done.

      I'm still on the fence about the "charge while walking" method. I need to do more testing, but I definitely wouldn't attempt to charge an iOS device directly while walking. An external battery pack works really well for this since it can trickle charge and not complain about varying voltage/current.

      Most new handheld devices are using 2A charge as standard.

      Apple 6 top charge rate is 8.6 watts 5volts 1.7 Amps While the iPhone 4s itself was too picky and would not charge directly, I was pleased to discover that the iPhone 6 seems to be more tolerant and with good sun. When you hike, the delivered power is generally all over the place. With the right controller and a larger setup delivering more power, the better the chance that enough power will be delivered continuously to satisfy the iPhone. What may be called "inefficient" in good sun may also be a requirement for continuous charging in variable situations. So for me there are three levels of demand in considering how large and heavy a system to design): (1) deliver just enough usable USB power to meet my power needs to a battery or device like the Steripen; (2) deliver enough correct power for direct-to iPhone charging when in acceptable sun; (3) deliver enough power for an iPhone with wildly varying charges while walking. It’s the phone that presents the biggest challenge. In the past knock off chargers made in China caught fire and I phone paid a heavy fine & a serious bad rap on the internet due to something they had nothing to do with – Apple’s chargers were superior and not catching fire. To fix the problem both Samsung use a resistor bridge hidden in the charger and a smart sense circuit to combat this issue. When presented with a poor quality charger in three seconds your phone decides to charge at the faster rate, then notify you that you are doing it all wrong. To light up beep and flash an important message, you can actually drain the battery inside the phone while walking around. The smartphone can complain about all sorts of things when it comes to notifications.

      Solar Panels

      An important note on wattage. Solar panels are typically rated by the maximum potential wattage of their cells under ideal sun conditions. Unfortunately, in real word conditions we get much less final power output coming into our USB-powered devices when all is said and done. This is due to a variety of reasons, some of which include:

      • Solar cell not facing directly towards the sun. This could be due to poor panel aiming and low sun angle in the sky which is common in shoulder seasons.
      • Hazy/cloudy skies will reduce the strength of the available light. A twenty watt can accomplish 10 watts with the new tech that is out there.
      • Energy loss during the step-up or step-down process in the USB power module. This is the biggest cause of energy loss.
      • Not purchasing the right sized panel to collect the energy you want.
      • Phones smart charging circuits not accepting after the three second built in smart test.
      Goal Zero

      At the time of this writing 2017 does not have the latest panels over the counter or on line in backpacking size. I did see the Nomad 20 coming out – but too expensive. Goal Zero battery pack is more bulky and is rechargeable AA’s now have little value on the trail, I think they did that to power the Garmin 400T or accessories at the time. I did purchase one in the past and after a month returned it. Goal Zero addressed this by now offering “The Flip” Brick Charger, small and portable, 2600mAh with 1A output designed to give one full phone charge. It is already outdated, a 2A output is recommended.


      Anker

      20 watt Solar panels are exceeding my expectations at 15 ounces and dual port, for a long term outdoor adventure, free energy product! This is a latest tech panel that works well provided you can see some disc in the sky. I now have a test when I cannot see the sun with a pointing app. I have seen 1 amp + peaks on a very cloudy day. If it is drizzling I put it away.Amazon’s top choice this month>EXAMPLE


      Lixada 20W Solar Panel Charger 2-Port USB High Efficacy

      I add this panel with a concern, It appears Anker may be buying the same manufacture and stamping their name on it, and adding $25 to it. Deep in the customer feedback a grumpy young man asks Anker to back up the 20 watt claim and it’s a 15 watt panel. He may be right, I still have not done a full sun test. I was more concerned about cloudy days. Solar is an odd world that efficiency is less about math, and more about science side by side testing. Something I can’t afford to do. I post this for those that may want to do something cheaper and the panels are identical. EXAMPLE

      A picture of the panel to buy

      A picture of what not to buy. (see the silver lines)
      Why question the intentions of a road-crossing chicken?

      The post was edited 1 time, last by Wise Old Owl ().

    • Lithium charging bricks

      A little as five years ago REI really did not have an electronics dept. Today there are dedicated Isle’s to comfort electronics from Fit Bit to Luci. Charging Bricks all the rage right now – some claim to charge a Iphone 7 up to ten times. Example
      I own a small about the size of a credit card and other the size of my remote for the TV. They are fairly indestructible, out last your phone and once purchased, will be around for years. It is much easier to go from a solar panel to a brick battery then later recharge your phone at night and power a LED light at the same time. Anker is a leader for me. They are generally smaller, lighter & well thought out. When I buy one, they have worked for years. The IC tech prevents accidental discharge. Example


      Prior Threads appalachiantrailcafe.net/index…highlight=solar#post36333

      Solar now works in the shade, Thanks to Rasty (2014) fastcoexist.com/3030921/mit-st…t-still-work-in-the-shade

      Best article I have read on building your own Uber light Panels. You don’t have to cut the panels anymore, just buy the size that fits your needs about 6volts.

      backpackinglight.com/forums/topic/103211/
      Why question the intentions of a road-crossing chicken?
    • Astro wrote:

      But on the AT has this technology really reached a point where it is practical?
      I say yes. My hiking buddy Slingshot uses some kind of solar charger/battery pack that is the size of an iphone that he hangs on the back of his pack. In town he plugs it in and charges it. It will recharge even on cloudy days. Me I just turn my phone off take pictures with my camera and only turn on the phone once a day to check in. I can go a week at least on my phone. I do carry an extra camera battery.
      "Dazed and Confused"
      Recycle, re-use, re-purpose
      Plant a tree
      Take a kid hiking
      Make a difference
    • We are into the latest generation, and each year there are more and more breakthroughs, to say they are all alike is a mistake. If I can't see the sun and can still get a charge, that's practical! So instead of charging your phone direct - store it to a lithium battery and charge your phone daily. Its like comparing a Tesla to a Model T.



      There is a caveat. The bigger the battery the longer the charge. Some larger Anker's require a six hour charge. A smaller two Amp output can be obtained with a short charge.
      Why question the intentions of a road-crossing chicken?
    • jimmyjam wrote:

      Astro wrote:

      But on the AT has this technology really reached a point where it is practical?
      I say yes. My hiking buddy Slingshot uses some kind of solar charger/battery pack that is the size of an iphone that he hangs on the back of his pack. In town he plugs it in and charges it. It will recharge even on cloudy days. Me I just turn my phone off take pictures with my camera and only turn on the phone once a day to check in. I can go a week at least on my phone. I do carry an extra camera battery.
      And you probably get better pictures than those of us using phones in airplane mode.
      The road to glory cannot be followed with much baggage.
      Richard Ewell, CSA General