walkhighlands

Add reviews of outdoor gear and equipment here... or simply chat about gear and ask for recommendations

Solar phone charger

Solar phone charger


Postby Poocini » Sun Apr 18, 2021 7:19 am

Can anyone recommend a solar phone charger? Hoping to do a bit of long distance walking this year, but would need to stay in touch - not to mention photos etc.
I know in the past the response has been to use a power bank instead, given how weak most solar chargers are, but with technology moving on so rapidly I'm hoping that someone has got their hands on a more recent one that's a bit more efficient!
User avatar
Poocini
Munro compleatist
 
Posts: 57
Munros:18   Corbetts:3
Sub 2000:2   Hewitts:5
Joined: Sep 8, 2013

Re: Solar phone charger

Postby SteveNorthumberland » Sun Apr 18, 2021 8:37 am

I have the one linked below and it’s sat in my living room window facing south since January and despite all the rave reviews the charging is basically in equilibrium with natural battery drainage.

https://www.blavor.com/cms/a/3.html

Despite this being sat in my window for so long only once has the strength meter hit 4/4 lights, will see what it’s like the rest of this month and into May and as I’m doing the west highland way I have a decision to make risk this or take my big Anker block which is 500g but is tried tested and trusted, all my Apple accessories are Anker in my opinion they are the best.

The only one I’ve seen recommended for the uk due to the solar strength here is the Anker 24W but it’s heavy. Sorry can’t remember where I saw this recommendation it was on one of my rabbit hole excursions on google.

https://www.amazon.co.uk/dp/B08FJ12RTM/ref=cm_sw_em_r_mt_dp_FH8P8D4THGPRGMAP9EPC

This would be a consideration if it didn’t weigh 1.2kg and cost £70 my pack weight is low enough to accommodate it as a luxury item but for a few days not worth the expense or the weight.

Anker also do a 21W which isn’t quite as big but not recommended for uk weather but could be a consideration if you wanted to save some weight.


https://www.amazon.co.uk/dp/B012VL20GW/ref=cm_sw_em_r_mt_dp_F99A10FX86539NE5CSBV

According to Amazon this is half the weight of the one above and £60 but I am no solar charging expert but isn’t powerful if that’s the right word for often cloudy uk conditions but may work well enough if it’s going to be sunny.

I am going to give my one at the top a real life 5 day test at some point and see if it works if it dies I am just going to take my huge 26800mah Anker block at 542g which I know will last me as it’s tried and trusted. I know Anker do newer blocks but this has 3 usb-a ports and I need 2 as opposed to the new one which has 1 usb-a and usb-c ports. As I’m using an Apple Watch and iPhone 8 I need the a ports.

I hope this helps as it’s an area I keep looking at as I’d like to be power self sufficient as I’m guessing that’s your aim.

This is just what I’ve found from my interweb searches on the topic please anyone feel free to correct anything I’ve said if it’s technically wrong I’m not a solar scientist the rest is just my opinion.
SteveNorthumberland
Backpacker
 
Posts: 21
Joined: Nov 22, 2020

Re: Solar phone charger

Postby AyrshireAlps » Sun Apr 18, 2021 12:52 pm

I generally try to have a full battery at the start of a day in the hills, and put the phone in airplane mode for the duration. Even using OS app and taking pics, I'm never below 80%, tbh generally over 90% at the end of a walk.

I've a 5 day self supported Cairngorm trek in June, I'd like to think by switching the phone off at night, and using airplane mode, I'll be fine just using my wee Anker powerbank (which will be used for Garmin inreach and vivoactive 4 watch too).

Switching off Bluetooth on the Garmin watch means I get a couple of days GPS use on that too.
AyrshireAlps
Stravaiging
 
Posts: 126
Joined: Nov 10, 2020

Re: Solar phone charger

Postby prog99 » Sun Apr 18, 2021 10:31 pm

SteveNorthumberland wrote:I have the one linked below and it’s sat in my living room window facing south since January and despite all the rave reviews the charging is basically in equilibrium with natural battery drainage.

https://www.blavor.com/cms/a/3.html

Have your tried it outside the window? I've a panel to keep my van battery topped up and the difference in and out the van are quite marked.
User avatar
prog99
Walker
 
Posts: 1391
Joined: Aug 14, 2013
Location: Highlands

Re: Solar phone charger

Postby SteveNorthumberland » Mon Apr 19, 2021 2:51 am

prog99 wrote:
SteveNorthumberland wrote:I have the one linked below and it’s sat in my living room window facing south since January and despite all the rave reviews the charging is basically in equilibrium with natural battery drainage.

https://www.blavor.com/cms/a/3.html

Have your tried it outside the window? I've a panel to keep my van battery topped up and the difference in and out the van are quite marked.


No I live right on the street and someone is liable to walk away with it.

Had an email off alpkit yesterday they also do one.

https://alpkit.com/products/flare-usb-solar-panel-charger
SteveNorthumberland
Backpacker
 
Posts: 21
Joined: Nov 22, 2020

Re: Solar phone charger

Postby AyrshireAlps » Mon Apr 19, 2021 8:04 am

That looks decent, and 300g isn't bad, about the weight of a spare midlayer.

I'd like to know the real world charging time for a phone in an overcast summer day though. Some interesting experiences in the post below.

https://www.trek-lite.com/index.php?threads/doubling-up-solar-panels.7135/
AyrshireAlps
Stravaiging
 
Posts: 126
Joined: Nov 10, 2020

Re: Solar phone charger

Postby rgf101 » Mon Apr 19, 2021 9:13 am

I just don't think the tech is there for solar phone charging yet. Say you've got a 2,500mAh phone battery (about right, the iphone 12 is 2,800, the 12 mini is 2,200 give or take. An anker 10,000mAh power bank weighs less than 200g and gives you 4 full charges. Say 3 to be conservative. Airplane mode, occasional photo and map use, and that's got to be several days use.

Compare that with a solar panel weighing probably more, which requires the right conditions to even work well and is more of a faff... I know which I'm sticking with.

Would be interested to know if I've got the maths wrong, or any real-world experience that contradicts this, but for ease and reliability and weight, I'd stick with the battery pack.
rgf101
 
Posts: 401
Joined: Jan 21, 2014

Re: Solar phone charger

Postby SteveNorthumberland » Mon Apr 19, 2021 9:56 am

that sounds about right from what i have read but i am no electrical expert

at the minute i am leaning towards taking my anker 26800 powerbank as like i have said its tried and tested as well as i trust it.

it has the power to charge my big ipad a few times let alone my iphone on airplane and low power mode as well as my watch.

if someone comes on and comments with the exact figures i will consider changing my mind but i am not convinced by my solar charger, might be worth it for an overnight trip but not say 4 nights.
SteveNorthumberland
Backpacker
 
Posts: 21
Joined: Nov 22, 2020

Re: Solar phone charger

Postby prog99 » Mon Apr 19, 2021 2:03 pm

What you could also do is charge a battery pack with your solar. That’d possibly be more productive.
User avatar
prog99
Walker
 
Posts: 1391
Joined: Aug 14, 2013
Location: Highlands

Re: Solar phone charger

Postby SteveNorthumberland » Mon Apr 19, 2021 2:53 pm

prog99 wrote:What you could also do is charge a battery pack with your solar. That’d possibly be more productive.


I did consider that but it just adds weight
SteveNorthumberland
Backpacker
 
Posts: 21
Joined: Nov 22, 2020

Re: Solar phone charger

Postby rgf101 » Mon Apr 19, 2021 3:43 pm

More weight and inefficiency - by all means top up a power bank when your phone is at 100%, otherwise you're just adding another chemical>electric>chemical conversion process.

I'd be inclined to have two smaller power packs than one large one - I've been thinking recently a small, fully-charged power bank, tucked away in a waterproof bag, could be a very useful emergency item these days.
rgf101
 
Posts: 401
Joined: Jan 21, 2014

Re: Solar phone charger

Postby davekeiller » Mon Apr 19, 2021 6:32 pm

Doing some back of the fag packet type calculations.
Solar irradiance is about 80W/m^2 in Scotland.
The Alpkit solar panel is about 25cmx30cm = 1/12 m^2
80/12 = 6.5 Approx.
so if the system was 100% efficient, I'd expect to get about 6.5W out of it.
However, it won't be 100% efficient, it will be closer to 10% efficient. so we'll get more like 0.5W out of it.
Output is 5V, so we're talking 100mA output.
a modern phone battery has a capacity of 3,000 to 4000 mAh (milliampere hours)
3000/100 = 30, so I'd expect it to take about 30 hours to completely charge a phone.
Even if I'm a factor of 4 out, it's still going to take a full day to charge your phone.
davekeiller
 
Posts: 596
Munros:145   Corbetts:23
Grahams:4   Donalds:3
Sub 2000:7   Hewitts:19
Wainwrights:20   
Joined: Oct 25, 2013

Re: Solar phone charger

Postby Marty_JG » Mon Apr 19, 2021 8:12 pm

Don't forget if you're walking you're not always in a position to angle your solar to the sun.
User avatar
Marty_JG
Backpacker
 
Posts: 1055
Munros:8   Corbetts:2
Sub 2000:3   
Islands:3
Joined: Sep 12, 2016
Location: Glasgow

Re: Solar phone charger

Postby jolly47roger » Wed Apr 21, 2021 12:55 pm

I thought efficiency had reached 20% nowadays. But even so, it is clear that a panel needs to be at least 50cm/2feet square to provide an adequate charge.
Thanks to Dave for his calculations which have saved me wasting my money!
jolly47roger
Mountaineer
 
Posts: 42
Joined: Feb 20, 2013




Walkhighlands community forum is advert free


Your generosity keeps this site running.
Can you help support Walkhighlands and the online community by donating by direct debit?



Return to Gear and Equipment talk

Who is online

Users browsing this forum: No registered users and 11 guests