Charging on the move.

Discussion in 'Touring and Adventure Cycling' started by Ice2911, 4 Nov 2018.

  1. Ice2911

    Ice2911 Über Member

    I have to admit I’m getting more and more into cycle touring and becoming more self sufficient. I have a Genesis Tour de Fer, my set up is in the picture. I have used a power pack with tiny solar panel in my bar bag to keep things charged. Just my phone and Garmin really. Charging the power pack at cafe stops or campsites. However as I get more and more adventurous I’d like to be able to charge on the move. So the questions:
    Is charging from front hub best option, if so what would you recommend?
    Would you charge to the power pack or straight to the devices?
    Would your recommendations work on my bike?
    Rough idea of what this might cost me?
    Thanks in advance

    Attached Files:

    Bored Man and MachersMan like this.
  2. 13 rider

    13 rider Guru

    I beleive it's best to charge electrical items like phones from a power pack as you get a constant supply so charge the power pack . Lights are ok to charge from a hub . Hub is probably the best options
    Bored Man, raleighnut and Ice2911 like this.
  3. cosmicbike

    cosmicbike Perhaps This One..... Moderator

  4. OP

    Ice2911 Über Member

  5. Edwardoka

    Edwardoka Bloviating Windbag

    I had an E-werk and a Lumoteq IQ running off a Shimano Alfine DH-S501 hub a couple of years ago.
    Worked flawlessly, despite my rubbish wiring, even in torrential rain. Transformed night riding for me, if you'll pardon the pun.
    Gravity Aided, Bored Man and Ice2911 like this.
  6. andrew_s

    andrew_s Guru

    For hub dynamo charging, you will want to use one of...
    Shimano - anything with 3N or 3D in the name, or the Alfine (not 2D/2N, 1D/1N, or Capreo)
    SON 28 (not XS or Delux)
    SP Dynamo PDxx or PVxx (not SDxx or SVxx)

    A Shimano 3N72 is the common "decent but not too costly" hub. A 3N30 works OK, but is of relatively basic quality, and will give more drag out on the road.

    Generally, hubs and wheels are cheaper bought from Germany.

    There are a whole load of USB charging devices available. Good ones (like those on the SJSC site) are relatively expensive.
    Cheaper devices are available, but I'd advise being cautious about leaving them connected to the hub whilst they aren't actually doing any charging (eg when the power bank reaches "full").

    Solar panels can be used successfully, but you need a fairly large one - a square foot or so, rated at 14 to 20 Watts.
    The rating is for the middle of the day in Africa, no clouds, and with the panel square on to the sun. In the UK, with clouds, and the panel on the back of the bike pointing any which way, you'll be doing well to get 1/3 of the rated current, even in summer.

    It's generally better to charge via a power bank, as that way you'll be extracting maximum energy from the hub. If you want to power something like a Garmin during the day, rather than recharge overnight, it's worth looking for a powerbank that allows simultaneous charge and discharge (sometimes called pass through charging). I use a Zendure A2.

    If you do want to power something on the move, note that USB plugs and sockets are neither waterproof nor mechanically robust. I'd recommend a 90 degree plug with the cable anchored close to the device being charged - it would be unfortunate if road vibration on an unsupported cable broke the socket in your phone or Garmin.
    Last edited: 4 Nov 2018
  7. HobbesOnTour

    HobbesOnTour Über Member

    The Netherlands
    I have a hub dynamo setup on my MTB convert and I highly recommend them.
    @andrew_s above is spot on with all his observations.
    I'd add also;

    Not all Garmins work flawlessly with dynamo power. My trial of a Touring unit failed and one reason was that it went haywire when connected to the hub. (My Wahoo Elemnt has no such issues).

    The power generated depends on the speed you cycle at (and also wheel size). Slow average speeds (such as off-road) may mean minimal or non-existent charging. On 26 inch wheels, my set-up will happily charge at 13 kph.

    Charging to a powerbank, then using that to charge, for example, a phone, is not the most efficient method due to a loss on each side of the equation. However, in practise it is the most effective. I'll charge either my powerbank or my Wahoo from Hub, nothing else. A pass through powerbank is the most effective way to charge your phone or other sensitive electronics on the go. (Not easy to find, though)

    I use a Son 28 dynamo in 26 inch wheels, put together by SJScycles.
    My USB charging device is the Cycle2Charge unit. A small German business, simple and relatively inexpensive and unobtrusive on the bike.
    A generic powerbank sits in my handlebar bag and is charged as I ride.
    On a typical day I'll generate enough power to top up my gps, phone and have some juice left over to charge kindle/batteries etc.

    Since I stop a lot, I normally carry an old fold out solar panel. It's only 7W but actually works very well when in direct sun and facing the right way. However, it is minimally effective when strapped to the bike.

    As for cost? How long is a piece of string?
    You need a hub, either incorporated into your wheel or a new wheel.
    You need a charging unit
    Possible upgrading of lights/powerbank
  8. Heltor Chasca

    Heltor Chasca Out-Riding the Black Dog

    I charge mainly from the hub. My Audax has a Son and my tourer a Shimano hub. My secondary sources are from power packs. The little one (Thrunite) which I use for Audax has a capsule which you can replace the ‘vaping’ battery if need be and if you are doing long rides you just put a fresh battery in. I also use a solar panel which is fantastic. Three large panels which fit perfectly on top of the rack or clips to the tent. Less than £40 on Amazon.
    Last edited: 5 Nov 2018
    Ice2911 likes this.
  9. OP

    Ice2911 Über Member

    4619FD3F-EBEB-4DF5-9528-91CEAAF0E22C.jpeg 09656728-1149-4699-B8EA-084151FFA4A7.png Thanks for the advice, I have had my wheel rebuilt with the Shimano Alfine hub. The e-works has just arrived so I have the fun of wiring that up. I’m looking at ways to keep the USB part dry, looking at adapting a weatherproof cable connector box and fixing it to my bar bag attachment. I will chargecto a through and through battery pack.
    Does the actual e-work and connectors to this need weatherproofing?
    Once again I appreciate your advice
    Edwardoka likes this.
  10. Edwardoka

    Edwardoka Bloviating Windbag

    The e-werk itself is a sealed unit with fixed cables that lead to connectors which are threaded to keep water out.

    After a couple of days of cable tie scratches on my leg I ended up taking the e-werk off the top tube and put it in my bar bag alongside the rest of my electronics. So long as you make sure that the cable is angled up as it goes into the bar bag so that no water can run down it into the electronics, everything should stay nice and dry.

    When it came to wiring the e-werk and light to the hub, I did it like the attached crude diagram.
    Stripped the wires coming from the light and e-werk and twisted the positive together from each pair to make one single wire for positive, repeated for negative and slid shrink wrap over the exposed copper (Important step otherwise you run the risk of short circuits when wet!) leaving enough exposed to go through the holes in the lego-looking connector, right through and double back into the two grooves that line up with the terminals on the hub.

    Plugged the lego brick onto the hub, spun the wheel with the light on, saw that it worked, and then cable tied the combined cables to my fork. You don't want those getting snagged on anything.

    There will almost certainly be better ways of doing all of this - I ran out of time during tour prep so all of it was done in a campsite with a bike multitool.
    (It turns out that it is exceedingly faffy to strip wires to length with a multitool...)

    Good luck and happy wiring!
    Last edited: 17 Dec 2018
    mickle and Ice2911 like this.
  11. Tigerbiten

    Tigerbiten Veteran

    I use a hub dynamo to directly keep a Garmin satnav working and a solar panel to keep everything else charged ( AA batteries and Kindle) via a cache battery.
    On tour, I can go for months without plugging into an external source of power ....... ^_^

    The above is roughly how I've wired up my dynamo system.
    The only real difference is I've a connector inside the front boom on my recumbent trike that I've wired the e-werks into as opposed to wiring it directly to my SON XS-M hub.
    With a 20" wheel my min speed to keep the Garmin Etrex 30 working is around 3 mph with the lights off and just over 4 mph with them on.
    The only trouble is the Garmin tries to switch off if I stop, so I'm thinking about getting the B&M cache battery for it to solve this problem.

    On my large Carry Freedom trailer I've a 20 watt solar panel again feeding through an e-werks into a large cache battery with a couple of supercapacitors used to smooth the output of the e-werks.
    The advantage of the 20 watt panel is it will just charge in light full overcast conditions as long as the panel is not shaded by any overhang.
    Very much smaller than a 20 watt panel and you're not going to get a charge unless you set up in direct sunlight facing the sun.
    Ice2911 likes this.
  12. I'm also looking at solar panels, some on Amazon have a five volt diode and can be wired in series, but I'd always use a powerbank to charge to. This is because I wouldn't want to risk blowing up a phone or camera battery, but a powerbank can be replaced for less.
  13. andrew_s

    andrew_s Guru

    I'd recommend a powerbank with pass-though*, like the Zendure A2, rather than the eWerk cache battery.
    The eWerk cache gains on weatherproofing, but loses on everything else, such as using it to charge the phone in the evening.

    * pass through is the ability for the powerbank to charge or power a device whilst simultaneously being charged (subject to the power supplied or required). Most powerbanks are either being charged, or supplying power, but can't do both at the same time.
    Dogtrousers likes this.
  14. OP

    Ice2911 Über Member

    I’ve just got my A2 and I’m looking forward to trying it out.
  15. mjr

    mjr Comfy armchair to one person & a plank to the next

    I think that's overstating it, unless your charger is particularly demanding (a hub dynamo output is only 3 watt nominal, after all), but of course a bigger panel is usually better, especially as each extra drawback (facing the wrong way, overcast, and so on) loses a few more watts.
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice