Hi Jonny,
Envious of your plan to tour Foggie Olde -- and in autumn and winter no less!
A few notes on generating & using electricity on your bike.
First, what do you need it for? You mention charging your phone and your camera. What about lights? Autumn/winter in the British Isles will have short days and lotsa wet as well. How will you see & be seen? The answers to these questions will shape how you generate, store & use electricity.
That said, this is how I handle the issue. On my Raven, I have three battery-powered lights, one headlight and two tail lights. Note here, that I use the headlight (a Cygolite) primarily to be seen, hence on flash mode -- I rarely ride at night, as I like to finish my day around 4 PM or so, in time for a cuppa as I set up camp.
When I'm touring, I also have a phone, usually a camera as well, and a small headlamp I use in camp. To feed all these devices, I use an Anker 5200 MAh storage battery.
I have a SON28 dynahub--that was part of my spec when I had my bike built in 2014. Several people on this forum speak well of both Shimano and SP hubs, and both are less expensive than the SON item.
The SON28 is hooked up to a Sinewave Revolution charger. (See my post of a couple of days ago on the wiring set-up for the hub and charger, in the thread on "Best Bike Components".) I'm now on my second Sinewave. The first one worked perfectly for 5 1/2 seasons (2014 to mid-2019) and then it didn't. I couldn't get a clear fix on why my original one died, but it appears that the USB port which delivers the charge from the unit loosened on its moorings. As a result, the charge from the unit to my phone, storage battery, etc., was intermittent.
Nonetheless, I'd recommend the Sinewave charger. It's sturdy, very compact, and performs as advertised. It's not a bargain at ~USD 120 + shipping, but it's functional & well made. Mine lives on the Thorn Accessory T-Bar, right behind my Arkel handlebar bag, hence shielded from the elements.
You'll need to connect your dynahub to the charger. (Before doing so, you'll need your dynahub built into your wheel.) You don't have to do this yourself -- a competent bike mechanic (or maybe your wheelbuilder?) should be able to set up the wiring and connections.
Before you order or build the wiring, however, you need to decide: am I going to use the electricity from the hub to charge only a storage battery, or both a light and a battery? Reason is--and I learned this the hard way--that my SON 28 is advertised as charging both a light and a battery, but it doesn't.
Originally, I set up a dual circuit, one to a headlamp, and one to my Sinewave charger, which in turn was connected to my Anker storage battery. This dual-charging capability was a feature of the SON 28; the more expensive (and slightly more efficient) SON Deluxe, by comparison, does not allow this. Problem was, I learned, that the headlight takes priority in the distribution of power. The headlight I had at the time (an AXA product, from Europe) was either "on" or "off" -- it had no flashing mode. When it was ON, very little power reached my Anker storage battery. (I came up against this problem in Sept 2014, on a tour of Denmark, Sweden, and northern Germany. Happily, I was able to find a set of mains in every campground, and recharged my Anker that way.)
When I got home, I resolved the dilemma by removing the AXA headlight and converting my dual circuit from the dynahub to a single circuit, charging only the Sinewave, and from that my Anker battery.
This works perfectly for my needs: The SON28-plus-Sinewave will charge my Anker from near empty in about four hours of riding in gentle terrain. I use a "splitter" (a one-into-two USB cable) to connect two devices at a time to my Anker. I avoid running my phone, etc., down below 50%. That way, I can connect my phone and my camera (for example) at the same time, and recharge both in a couple of hours before I go to sleep. This task runs the Anker down only by about 50%, so that it is then fully recharged well before lunch the next day. This cycle just becomes part of the daily routine on tour.
Because I use the Cygolite headlight only on the flash mode, it usually lasts 3-4 days before I recharge it. My tail light usually needs recharging every 3 days. So, there's rarely a queue longer than two devices on any given evening.
(My headlamp uses 3 AAA batts, and get recharged maybe once a week, so is not usually in the queue.)
Hope this is helpful, Jonny, and not too much "stuff". There's another level of detail, but we don't need to go there, unless this arrangement seems workable for you.
Good luck!
John
