? about Solar chargers
 

I've skimmed thru the search list on this topic, but don't think what I'm asking is on there. I'm interested in finding a solar charger for my stupid phone only so I don't have to waste time at the library every day. I live on my bike, so it would have to be small enough and light. It's sounding like the smallest is still too big for what I'm imagining. So enlighten me as to what's out there and the cost. I checked them out briefly on Amazon a while back and saw they go as low as $20. But I don't really know if it was what I'm wanting. Thanks.

I got this: https://www.amazon.com/gp/product/B012YUJJM8/
Seems to do the job, although I haven't used it a lot. It works a lot better when you can just sit it in the sunlight, but I've also gotten use out of it by draping it over my rear rack or handlebars. I did notice I was having problems with it the other weekend, but it eventually worked. I don't know if there was a short, if just hadn't been used in a while and had to charge some internal battery or capacitor, but if there's a bad connection, then that's disappointing, because I've only had it about a year and not used it much. But once it started working, it kept working.

When using it on the bike, I recommend charging a battery, rather than the phone. I find that my phone doesn't charge well with an inconsistent source of power. Sometimes it even dies faster because every time the power starts or cuts out, the screen comes on. So I charge the battery and the batter charges the phone.

Yea Size matters in solar panels,, and keeping the panel perpendicular to the direction of the sun.

I have one of these and it serves its purpose well for me. But it depends on how much sun you get on a regular basis. On one 3 week tour I only had 3 days of sun and on a 2 week tour I had only two days of rain.

https://www.amazon.ca/Instapark%C2%A...rcury+10+solar

https://farm5.staticflickr.com/4253/...31abfe7e_z.jpg

Spectacular pic. Where is it and what's the bike?

That's Mt. Chephren (Chephron?) Along the Icefield Parkway between Lake Louise and Saskatchewan Crossing.

The bike is a 1991 Marin Chromoly rigid mtb converted for touring. Trekking bars, Marathon tires, Brooks saddle and a Sram 42/32/22 crankset wìth a hybrid bikepacking set up. I did a mix of road, gravel and non technical singletrack on that tour.

Unless you spend more and get a bigger panel, it will take all day to charge the phone and even then it might not be a full charge. Other options include; get a power bank you can leave somewhere charge up and use it when needed or jury rig a tire generator/dynamo to charge to usb.

I would charge a battery and then charge devices off of that.

I do not think these panels are made any more, has a USB port but no internal battery. In bright sun if aimed right it will put out a bit over 300 milliamps (1.5 watts) that is enough for some devices but not for some other devices. My phone will charge slowly. In the photo I am charging two AA batteries, but that panel does not put out enough wattage to charge more than two AA batteries with that AA/AAA charger.

I have never used this panel on a bike trip, I have a dynohub and rely on that instead. I took the photo on a kayak trip.

I learned a lot about charging devices on trips from this link, I do not know if it would answer any of your questions but it is packed full of good info.
https://www.crazyguyonabike.com/doc/?doc_id=9258

It looks like it has not been updated for over four years, some of the products mentioned are no longer made. For example it describes a Pixo C-USB which I think is no longer available. But I still found some of the information very informative.

I have an Enerplex Kickr 4. Lightweight, flexible, and relatively compact. In strong sun it works well...take away the strong sun and it's not very useful, just like any other small panels.I believe they have since been forced out of the market, but I would find something similar.

Solar power, is VERY highly relative to cost, and I do mean highly relative to cost... $300. will work, sort of, $600 will work most times, $1,200. would work most times. :thumb: A $70 or less solar panel will fail most times... IN My Experience... :p Now if you just want to charge your phone.............. :innocent:

I'd go dynamo with the sinewave revolution, way more efficient and reliable. It costs more upfront though if that is a concern.

I've used this for mountaineering trips. Charges a 1250 mAh battery (4.6 Wh) in about 4 hrs in full sun at 10k+ ft. Lower altitude would bring the output down some.

Cheap, doesn't weigh much and folds up. Has eyelets for lash points so you can strap it to the top of a pack or paneers, or hang it from something pointed south in camp.

https://www.harborfreight.com/5-watt...ger-60449.html

Use it to charge a battery or two, not directly to the phone. From tests / reviews I've seen of similar size /weight panels in backpacking and climbing circles, the ones costing several times more don't seem to perform much better. Certainly not enough better to justify the difference in cost.

That 10W amazon rig looks like it's big brother.

Go for dynohub
 

If you want to charge your phone *while riding* forget solar panels and get a dynamo-hub + charger + power bank (like this one . I know it costs so much more but it is a one-time expense and with a little planning and foresight it will pay for itself multiple times.

Solar panels are not great for cycling because:
1. You need to keep them facing the sun; output power falls of rapidly as angle increases. You need a very large area to reliably recharge your batteries every day during the daytime.
2. Output power falls off faster than input power due to the electrical characteristics of the panel and electronics.

You are correct on all counts, but there is always an exception to practically every rule of thumb... There ARE foldable solar panels that CAN, charge pretty well everything you can imagine you would want to charge on a bike trip... All it takes is $$$ and stopping for an HR or two to spread it out... ;) BIG $$$, like $1,200 to $2,600. :eek:

For all one says I did two weeks without hooking up to the grid using a panel.

A dynohub is also pretty useless if one is not racking up big miles on a regular basis like camping for a couple of days in the same spot.
There are different solutions for different applications.

He literally said exactly that, he just wants to charge his phone. $1200-$2600 just to be adequate for a tour? Mmm, things have gotten cheaper since 1999, unless you are bringing an electric blanket, cooking range, fridge, iMac, etc.

On a bright day in Hawaii I can charge my iphone 5 in about an hour and a half...granted the sun is extremely strong here, but for $40 that's not bad.

:crash:

Exactly, I too have done 6, 10, days without plugging into a wall socket for power. It all depends on what you use and what you need... and.... How much $$$ you want/can spend to make it work... ;) I guess, my "real" point is/was, trying to be that solar does work, and would work for ALL the power you would want/need... For ALL, even huge demands for power... I guess what I am really trying to say is that YES, solar does work and can work for ALL kinds of "demands" on it, It just takes some big $$$, this $60 BS solar panel fail, when a $600 solar panel is required and could do the job is not a solar panel fail, it is an investment fail. :innocent:

I concur, I can charge my phone in about 3 hours in bright sun in BC or Alberta. I noticed its quicker in New Mexico.
But there has to be pretty direct sun. My charger was about $60 five years ago, I imagine you could get much better ones today.

I think my panel was about 80 - 90 with battery.
I also like it because I do other things besides cycling and the panel can serve in those situations too.

I think besides investing in a charging system I would investigate a really large capacity battery. With a wall charger being available every so often it may be all one needs for certain tours.

Look into dynamo hubs. They're the ****. I would think it would be especially worth it for someone who lives on their bike.

You really need to assess which is better for you, dynohub with charger or solar panel.

Dynohub. Dynohub and charger can cost a few hundred or more if you are upgrading because that means you likely are buing a new wheel plus charger. I assume you already knew that because you asked about solar only. The hub option is best if you are building up a new bike because then you are only having to pay for the hub and charger, minus the cost of teh non-dyno hub that you would otherwise have bought.

Solar. Some phones (especially Apple) can be very picky about the power supply. Some people have had to use a charger to charge up their power bank, then use the powerbank to charge the phone. I showed a photo of my solar charger above in post number 9, that would likely charge my phone if I had bright sun all day and stayed in the campsite where I could periodically re-aim the panel towards the sun. But my phone is not an Apple, it is not very finicky about the charger, it will readily accept a charge from a low voltage/low current source.

But there are a lot of other factors:
- Are you camping where you get a lot of sun or a lot of clouds?
- Do you have your phone on all day, or only part of the day?
- Do you use your phone for other things like GPS tracking?
- Do you do a lot of data downloading?
- Do you make a lot of calls?
- Is your battery reasonably new?
- A phone if it is near a cell tower uses less power than if it is often searching for signal, are you always near a good signal?

Since you have not responded to any comments yet, I have no clue if you are even watching this or not, so I am going to quit here.

Agree. I have the ability to charge with my hub, but I also have a solar panel. I have used both, and have used them at the same time. On trips where I have both, I haven't always avoided plugging in, but I have managed to avoid always being on the lookout for an outlet. If I found that I had one readily available, I used it to top everything off, but if not, I had no issues keeping everything charged. I actually have found that solar on a sunny day works faster than dynamo. But if I'm pedaling all day, might as well put that dynamo to work.

Completely agree, but my point was that if one were willing to spend $$$ on solar, might as well spend $ or $$ on a dynohub setup instead

P.S Side note: I work on PVs and power electronics. PV panel efficiencies (currently ~20% at best) are the bottleneck and don't look like they will change much in the near future (next 20 years).

Depends.

It's not an easy answer. Probably the first step is to look at lowering consumption if possible. If you can reduce your power needs on tour you need less of a solution.

Second, you need to balance the style of touring you are doing with the mode of charging. Currently there are three main ways: from the grid, solar and dynohubs. Each have their pros and cons. Whatever the choice, the most efficient mode of charging is to have a battery that you can charge initially and then recharge other devices from. This allows you to set and forget instead of cycling each device through the charging device throughout the day.

The grid is the most reliable if it is available.
Solar is weather dependent.
Dynos are distance dependent.

While a dyno may seem more applicable one has to also weigh whether you need charging for other activities (Camping, canoeing, hiking) and whether one is only using one bike for touring. I cycle, camp, kayak and dive and use both a 26" mtb and a 700c road bike for tours so I want a multi use solution instead of a single use solution. My solar panel works great in the summer and I feel I can be completely independent of the grid with my panel on the bike as shown in the picture above but it would be far less efficient during shoulder and winter seasons.