UKC

I looked into these a few years ago and the general consensus seemed to be that they weren't much use.

Is this still the case or have things moved on enough to make them worthwhile? If so, what are people's recommendations?

It's for a bike tour in the north of Norway so plenty of daylight hours but maybe not so bright! Would it work in that scenario?

Easy answer is not great. There are solar flexi panels that need to point at the sun to get a full charge. I read the cheap Alex press models have varying degrees of output depending on how lucky you get. The branded ones are a lot more performance consistent.

Just done the digging for an upcoming trek and it seems battery preservation and a couple of powerbanks are the way. If you're using your phone for navigating then it could be another story.

There are some great threads on Reddit in the trekking pages.

Thanks. As we'll mostly be in campsites I'll probably just bring a charging block.

A panel small enough for travel is likely never going to be sufficient to meaningfully charge anything in my opinion.

I would suggest instead looking into battery banks and charges with quick charging rates. 

I ended up with UGREEN charger and powerbank which can charger at 65W. Which means that it will recharge itself with my phones worth of charging in just 16 minutes.

Been using a 12W panel for years, charges my phone, inreach and camera batteries. Used in Scotland, Northern Scandinavian and Wyoming.  Don't bother hanging it off your backpack, you swing about to much. Set it up as square on to the sun as you can, adjust it as the sun moves. A couple of hours every few days is enough to keep things topped up indefinitely. Weight 250g.

Please identify it!

I did briefly have a Brunton solar charger that just plugged straight into my phone. It was rubbish - no charge registered, even when sat on a windowsill in full summer sun!

If you go for power banks, I noticed at the weekend that TK Maxx have Veho PZ12 10,000mAh ones in for £20 down from £115.

I've got 2x PZ10 ones and they've been great.

Choetech, there's two panels 23 x 15cm in a case so you just open it up plug in your phone and away it goes.

Power banks are only good for a few days, once you've used up whatever charge is in them. You need to go somewhere with Power to recharge it. If you're going into the wilderness for several weeks you'll at some point run out of charge. I just like long trips away from the madding crowd. 

I bought a cheap one from Amazon and it was rubbish.  It would only just about charge a phone in full sunlight when angled towards the sun.  I sent it back.  I have upgraded to one which is double the size though which I bought from Alpkit.  What the person in the shop mentioned though was that to charge a phone takes a certain minimum level of volts / watts / amps (electricity is a bit of a mystery to me).  Hence small panels often struggle to charge them.  What it will do though is charge a power bank by trickling the power in during the day, which would then enable you to plug your phone in overnight.

I have conducted a bit of an experiment and it did indeed gradually charge a power bank so maybe what I was told was true.

As always, the best setup is a battery directly connected to a solar panel that you leave still, pointed at the sun. Fine for base camps etc, not fine when dangling off your rucksack. This is, and will remain, a fundamental limitation of solar energy production - you need to point the thing at the actual sun. 

I have personally always had great experience with Goal Zero stuff. Yes, it is more expensive than most others, but it actually works (within the realm of a solar panel). I use a 20W panel and a 100 Wh battery pack, and have had great success with it for phone and bike computer charging in Finland, Norway, and Greenland. On a sunny day it will charge from full to empty in c. 8 hours. 

Small panels don't produce enough power (watts) and modern devices require regulation of current (amps, and by proportionality, volts) to charge properly. Always charge an external battery from a panel, and the load (your phone) from the external battery.

I have had some success with a small panel from Decathalon for Scottish long distance walking.

But it does need to be sunny. If you can't see your shadow you won't get any charging done.

Full power charging is possible even late in the evening, when the sun in hovering above the horizon, if you point it right at the sun.

I have a 21w 2x USB outlet MSC charger for sale at the mo. Cost £120 as they are apparently the bees knees and used in extreme environments /war zones etc. Weighs 370g. 

Totally unused as the 16 day off-grid trip I planned in 2024 didnt happen for various reasons. I hung onto it but not sure I'll use it anywhere. 

Message me directly if interested in photos and the full spec 

I have a 20W fold out panel which works pretty well for topping up a battery bank. But as others have said, forget directly charging a phone and you really need to set it up and leave it pointing at the sun - so campsite rather than on the back of a rucksack. It might be OK (ish) strapped to the top of a pannier rack.

Welcome to borrow it BTW.

Cheers.

I've taken a punt on a cheapy one off Amazon, it's the same as Owen M recommended but branded differently. I'll see how it works.

I have had moderate success. I bought a decathlon slr 500 panel. To date i have only "tested" it charging a Belkin 20,000mah power bank. 

On a sunny summers day orientated south it will pick up 75% charge in one day. On a winters day under the same circumstances it sometimes picks up 25% charge. 

Roughly 30-40% is needed to fully charge my Iphone. I am cycling in finland in July and intend on strapping it on my oversized saddle bag. 

I have an Anker one, 20ish W I reckon. As per other posters, use it to charge a power bank in the day, use the power bank to charge to phone at night. On a bright sunny day, orientated well, it'll refill the 20kmA bank which has charged 2 iphones.

If you're going to be near power often enough to get by on them then your space/weight would be better spent on power banks that you recharge off the mains. 

If you're properly off grid the whole time then solar is it I guess, and yeah it does work if you leave a panel charging a power bank. I've done that. 

But for trips where you're doing the odd night in a proper bed here and there along the way, or if the campsite will let you plug in overnight, then bin off the solar and buy more batteries.

This won't work (from experience). You'll need to set it up at your camps.

With my various attempts at planning a longer bike trips (never actually done - the longer rides I have done, the Rebellion Way for example I did over 3 nights, two half days at each end and two full days in the middle - with a biggish powerbank) from looking into things, getting a dynamo hub for the front wheel always seemed the most logical solution to powering electronics. Have you considered this? It's not cheap but seems the way most people doing big tours go.

Where in Norway are you going? I don't know if it is relevant to solar panels or not but while I can sunburn reasonably easy here in the south of the UK, I've never burnt in Arctic Norway despite spending days on big routes in the sun. The same is true even in southern Finland. So despite the long daylight hours I don't think the sun has nearly as much energy in it as further south. Presumably that will impact on solar panel efficiency?

Where in Finland are you planning on riding? (Former long term resident and it's where I started bikepacking a long time ago! https://lightfromthenorth.blogspot.com/2013/12/an-early-winter-bikepack.htm... https://lightfromthenorth.blogspot.com/2013/09/bikepacking-new-bags-new-cam... https://lightfromthenorth.blogspot.com/2013/06/the-oaks-of-sweden-finland-b... for example!)

That's not really an option, I'm not willing to pay for a wheel I'll use for maybe one trip every 7 or 8 years. My wife has one though so it will be interesting to see how it works.

You can always leave the wheel on and use it anyway! My wife's bike is set up with a dyno hub and disc brakes so the rims won't wear, so in theory the wheel can last for ever

It's my mountain bike and I really don't fancy riding year round on technical terrain with that extra weight in the front. I'd also worry about how long it would last in the mud and being submerged in rivers. 

I've got an older Anker 14w and a new Anker SOLIX PS30. Both have been excellent and used on multiple multi-week expeditions in the Arctic to charge; InReaches, Kindles, two-way radios, vapes, headtorches etc. If you are going to be leaving it setup through the day then I find charging a battery bank is better and more convenient. Phones really don't like the intermittent charging. Also point it in the direction of where the sun will be at midday, that's when you will get the most charge.. An essential piece of kit for me on any multi-day stuff and when paired with a small power bank will be lighter then carrying a massive power brick.

How about a clip on rim system?

https://www.velogical-engineering.com/dynamo/product-information/?lang=en
 

https://shineturbine.com/?srsltid=AfmBOoq2ADaOP_mKbILhb3qTYZUoAmVlBb5ibHdxU...

Had anyone tried wind generators like this one? Would work in the evening overnight if in a windy camp.