I’ve just been to northern sweden backpacking, and as part of my kit, I took 9 batteries for my Canon DSLR.
That might sound excessive, though considering I was going for 12 days, my camera was the only source of “entertainment” I was taking, and I was planning on shooting lots of video – not just photos, I felt that it was probably a fair estimate – 75% of a battery per day.
The thing is, carrying batteries is the least sustainable solution to powering electronics in areas where an electricity grid doesn’t exist.
I’d have dearly loved a viable option of recharging these batteries – they’re all rechargeable batteries after all – but the options seem fleeting, and a bit rubbish.
There’s a stove with USB that can be considered, until you realise the weight involved and that you have to use wood as power.
There are other heat based options – things that you put in a pan of boiling water until , but they’re a bit rubbish too.
When I went to Morocco – I saw people using solar chargers, which is all very well until you see all the marketing aim towards “providing that bit of charge needed to make an emergency call”. If you have a low usage application – such as a Mobile phone on standby or for emergencies, and you have a sunny environment, then you can have quite a sustainable setup – there are mobile phones that have incredibly long battery lives – so if that’s your sole power requirements, then it could be a light, cheap and sustainable solution. It is, however, a completely rubbish option if you have requirements for power above “very light” – in most environments, even very sunny ones, it won’t recharge a fully discharged smartphone battery in one day, and don’t even think about using it for other things.
I have a Proporta external battery for my mobile phone, but even that can only manage to recharge my phone twice, and was considerably more expensive (and heavy/awkward) than simply buying two spare smartphone batteries.
I think the fact of the matter is that power generation is difficult in terms of energy, and difficult in terms of presenting the power to ones peripheral devices – on this basis – as much as I wish it wasn’t the case, I can see carrying spare batteries to be weight and cost effective for a good time to come.