Solar panels invoke dreams of a sustainable future. The eco-geek in me has always wanted a rooftop lined with them to pay homage to Al Gore, but those things don't come cheap. In the meantime, what we do have here is a personal solar panel made by Sanyo, which includes an internal rechargeable battery, USB power out and LED lights. An excellent idea, but is it practical?
Judging by the Solar Ark, a 5000-solar panel building built by Sanyo in Gifu, Japan, it looks like Sanyo is serious about solar power. Using Sanyo's HIT (Heterojunction with Intrinsic Thin layer) solar cell, the eneloop Solar Light promises to deliver more power using less light. So, here's the test: powering an iPhone 3G entirely with the eneloop Solar Light for two weeks.
The eneloop Solar Light is handy to carry around, being practically a solar panel with a handle attached. The design is pleasantly clean, it looks and feels like a single solid piece. On the other side of the solar panel is a LED light panel, with a single LED beam light on the side of the Solar Light.
It's light at 80g, and works well with what a Sanyo representative explained as a target use: a secondary light/power source strapped to the backpacks of recreation campers, for those days in the wilderness when you just can't find a power plug.
Even without a full charge, the LED panel lights up brightly, especially if you use all nine lights on the panel. By pressing the Power button repeatedly, you can toggle between using the beam light, all nine LED panel lights, five lights in a cross shape, or a single light on the panel.
Pressing and holding the Power and USB output button for four seconds activates the emergency signal, where the LED panel will flash an SOS signal in Morse code. Advantages of using LED lights include lower energy requirements, more light per watt compared to incandescent bulbs, small sizes, shock resistance and longer lifetimes at the disadvantage of higher costs.
My day to day iPhone usage is minimal and at the end of most days, I'm still left with more than three-quarters charge from just a few minutes of calls, apps and surfing. For two weeks, I left the eneloop Solar Light in my car during the day when it's parked outdoors so that it gets direct sunlight. Once it manages to get a full nine hours under sunlight, the Solar Light can recharge my iPhone just fine during the night.
If it's a rainy day though, there won't be enough juice to recharge my iPhone back to full. Also, ambient light doesn't seem to do it for the Solar Light, on the weekends when I had it inside the house but not directly under the window, it didn't pick up much charge.
So it seems that, for my needs at least, the eneloop Solar Light can work as a secondary source of free power for my mobile phone on sunny days, and a secondary flash light for short emergencies. Although the power is free, the device isn't, and at S$255, it's really up to the inner eco-geek in you to see if this is one green product you'll want to invest in. Just keep those AC adapters and batteries around for a rainy day.