Our recent trip to the United States to do the John Muir Trail was the perfect opportunity for me to try out my latest gizmo, a SolarMio 3 lightweight solar panel. We planned to do the walk over 24 days and I wanted to take along my Apple iPhone. I was hoping the SolarMio would be able to recharge it along the way. I admit there was no reason to carry an actual phone along the crest of the Sierras as there is cold snap in hells chance of getting a connection. But I do use my iPhone for a variety of other purposes. Firstly, I’m addicted to the iPhone camera. Sure, I was carrying a Canon 5D Mark II for all of the usual high-quality stuff, but I have to say that I really love the immediacy and simplicity of the iPhone camera. I’m also fascinated with the various camera apps that allow me to quickly change how my images look and feel. Secondly, I wanted to listen to my music collection. I have thousands of songs on my iPhone and I figured that since we were confined to our sleeping bags by 7pm I would end up listening to most of them (my wife, Karen, was reading her Kindle and didn’t want to talk to me). Thirdly, I use my iPhone to write a daily journal and wanted to work on a few other text projects.
I bought the SolarMio 3 from the guys at Pinnacle Outdoors in Melbourne. The SolarMio is a foldable unit with three flexible solar panels. It has an output of 4.5V (300mA) and a battery bank with an output of 5V/6V (500mA). The battery is rechargeable Lithium Polymer and the whole lot weighs in at a reasonable 125g (a couple of Mars bars). I attached the panel directly to the back of my rucksack using elastic ties, which worked extremely well. Interestingly, we were walking the John Muir Trail from north to south and the back of my rucksack was often facing north, which in California means away from the sun. Despite this the SolarMio battery would usually fully charge over the day (especially if I placed the panels to face the sun in the last half of the day when we were in camp). A single full charge of the battery would see it deliver a reasonable 35 to 40% charge to my iPhone. This proved to be plenty of power to keep me shooting images, listening to music and jotting down my thoughts. Overall the SolarMio proved its worth, but we were hiking in sunny California. I wouldn’t want to bet the house that the SolarMio would deliver similar results when walking in less sunny regions such as Patagonia or Scotland.