These days we seem to be taking more and more electronic gadgets with us on tour. In some respects we would like to do without them and in some ways obviously we could, but we do like taking photos, we do have elderly parents who like to know they can keep in touch with us and the GPS has been useful. All of these gadgets have batteries that obviously need charging on a regular basis.
The obvious way to charge these gadgets is to use the mains chargers they came with and plug them into wall sockets at campsites. However this is not always possible and especially difficult if you are wild camping! We have tried various methods of charging other than using the mains.
We have tried solar panels but found that the small sized ones don't work very well in northern Europe where even with extended daylight hours there isn't sufficient sunlight. If you want to go down the solar panel route then you need solar panels that give out at least 12W, but these will set you back @£200+. They need to be flexible, waterproof and you will also have to work out a way of fixing them onto you bike to collect the sun as you ride as they will need several hours to charge anything and there may not be enough time or sunlight left to spread them out at the campsite in the evenings.
We have also tried wind chargers such as the Hymini. It sounds a nice idea, as you cycle along the air rushing through the mini turbine charges a small battery, which you can then use to charge your mobile devices. The Hymini may output a charging current, but if you read the small print it isn't enough to charge a phone or it's internal battery from flat. We have had two of these, which we used on two separate 4-week tours in Iceland. The first one didn't really charge anything very well so we sent it back and they replaced it. Unfortunately the second one again didn't charge anything with any success and that was with 4 -5hrs of cycling a day well above the 9mph they recommend. When you are wild camping you can't top it up from the mains easily to then trickle charge the battery as you go along, which we think is the way they intend it to be used.
The best success we have had with charging electronic gadgets other than obviously using the mains chargers is to use dynamos. Unfortunately the bottle dynamos that run on the side of the wheel don't give out enough power but the hub dynamos do. We have fitted Schmidt SON 28 Dynohubs on the front wheels of our bikes that we use to run Busch and Muller front and rear lights. By connecting the dynohub to an E-WERK hub dynamo powered universal power supply and charging unit they really do work well as a charging source. The 'e-werk' can be mounted on the bike or kept in a barbag and using a small plastic tool you can easily set it to provide a variable voltage (2.8 to 13.3 V) and current (0.1 to 1.5 A) using the adjustment knobs and the unit provides power of up to 16 W.
The E-WERK comes with numerous leads with several different connectors to fit various electronic gadgets including a USB female connector so you can plug in any USB leads that you might already have for your gadgets and a couple of leads with bare ends that you can solder your own connectors onto. We found this useful in making up leads for our camera and radio battery chargers. One thing you just remember is to change the output voltage when you change the gadget that you are charging, otherwise you could have problems! The e-werk also comes with double spade connectors which makes it quite easy to connect it to a hub dynamo if you are also using the dynamo for lighting.
This combination of kit may seem a serious out lay of money but it is well worth it as we have found it to be the most dependable system that will work in all weathers. We have successfully charged mobile phone, camera and rechargeable AA batteries from flat on tour. To give you an idea, we can easily charge a 2400mAh phone battery from flat in about 3- 4 hrs of moderately paced cycling. If you are wondering about dynamo drag by the laws of physics there will be some, however it must be quite small as we haven't experienced anything noticeable.
Obviously there are alternatives to the E-WERK system such as those made by Biologic, however they are only for charging phones and we decided we needed a system that had variable voltage and thus being able to charge other things such as camera batteries, rechargeable AA batteries etc.
E-werk Cache battery
We have found that adding the E-WERK cache battery into the system has been very beneficial in helping to keep everything charged. The cache battery is connected in series with the device being charged and when the device is fully charged it then charges up the cache battery which can then be used later to charge another device. The cache battery has a capacity of 1400 mAh which is enough to charge a mobile phone. We generally leave the cache battery connected to the e-werk which means that even if we forget to attach a device or have no need to attach a device as everything is charged we don't waste any cycling miles and have some stored charge ready to charge something later.
The cache battery also helps to smooth out any drops in voltage that will occur when you are slowing down or stopping. This is useful for devices which are sensitive to fluctuations in voltage and switch off when the voltage drops. For example I sometimes run our GPS directly from the e-werk to save batteries, before we had the cache battery when ever I stopped the GPS would switch itself off which was a tad annoying, with some charge in the cache battery it still keeps going even when you stop. The cache battery gives out 5v DC which is just great for all devices that use a USB connection to charge. You must however remember to remove the cache battery out of the system if you wish to charge devices of a higher voltage as this could damage the battery.
Charging iPhones with the E-WERK
We both have HTC phones and we have had no problem in charging them using the E-WERK, however there are apparently some issues with charging some versions of the iPhones using the E-WERK even with the cache battery. We suggest that you contact Busch & Müller the makers of the E-WERK if you have an iPhone.
Rechargeable Power Packs
One thing we have found very useful particularly when doing a lot of wild camping is to use a rechargeable Power Pack as a charger. There are small versions available such as the power monkey which have only a small capacity, but if you are out for any length of time and have several batteries that need charging what you really need is something larger with at least a 18000mAh capacity like the 'XPal' or 'Powergorilla'. They usually come with an array of leads and connectors that you can use to connect various electronic gadgets. The Xpal has 3 outputs USB(5v), 9-12v and 16-20v all of which we can used at the same time. The phones and 'AA' battery charger can charge off the USB output, the radio batteries charge off the 9-12v output and the camera battery chargers can work off either the 9-12v or the 16-20v output. Unfortunately we can't charge more than 3 things at a time, however if you are organised it is quite easy to keep a system going. Our Xpal 18000 after a full charge has enough juice in it to charge two phones, two camera batteries and our two radio batteries. Unfortunately we haven't had much success in charging the Xpal from flat from the e-werk as the output from the e-werk is to low which is a shame.
At around 515g in weight this may seem like a lot of extra weight to carry, however last year with the ability to charge from the dynamo hubs we could afford to leave the most of mains chargers at home and rely on the dynamo hub and Xpal combination. The weigh saved by leaving the chargers at home helped balance out the extra weight of carrying the Xpal.