Higher oil prices and political considerations have spurred interest in commercial solar power but this free and abundant source of energy is also being tapped to power a range of personal electronic devices including mobile phones, PDAs and laptops.
The first solar-powered device I owned was a dual-power calculator made by Sharp that could run either on its batteries or a tiny bank of photovoltaic cells above the LCD (liquid crystal display).
Sharp, a leader in solar power technology, still makes and sells a range of dual power calculators that automatically switch from solar to battery power in low light. They cost about £6.
Now, however, improvements in the efficiency of solar technology – the percentage of the sun’s rays that can be converted into electrical energy – coupled with declining prices are fuelling a surge of interest in solar power for consumer electronics.
For example, Freeplay Energy , the UK-based self-sufficient energy products pioneer, has a range of portable radios that combine Freeplay’s wind-up technology with solar power.
Similarly, The Electronic Zone, a UK-based specialist online retailer, sells a £30 solar headphone radio made using ultra-light thin-film solar technology.
Others have focused on building solar power technology into garments and bags. New York-based Voltaic sells a series of solar-powered shoulder bags and backpacks designed as self-contained mobile power generators capable of charging your portable devices.
The bags, sold in Britain by The Electronic Zone, cost from £159 and come with three lightweight, tough, waterproof solar panels embedded into the outside of the bag which generate up to 4 watts of power. Any surplus energy is used to charge a built-in lithium ion rechargeable battery pack for use later. The battery pack can also be charged using an AC travel charger or car charger (both included).
The bags come with a standard car cigarette lighter-style port ready to recharge most small electronic devices including mobile phones, digital cameras, two-way radios, PDAs and portable digital music players. They are not designed to charge laptops.
If you do not have a car charger, the bags come with a set of 11 standard adapters for common cell phones and other devices.
I have also been testing a pocket-sized portable solar energy power pack called FreeLoader made by UK-based Solar Technology International.
When closed, this clever little device is about the size and weight of a PDA in a silver-and-black industrial-style case. It opens into three parts, the main unit which contains a rechargeable lithium ion battery pack, and two solar panels that plug into either side of the battery pack like a pair of wings.
These charge the FreeLoader’s battery pack in about five hours when exposed to sunlight – alternatively you recharge the battery pack in about three hours by plugging into a standard computer USB (universal serial bus) port using the supplied cable.
Once charged, the battery pack supplies enough energy to provide up to two hours of talk time on a mobile phone, 18 hours of running time on an iPod or about 2.5 hours of playing time on a Sony PSP hand-held games console.
The FreeLoader comes with several cables and a big back of adapters designed to plug into the power sockets of lots of mobile phones and other devices including BlackBerry mobile e-mail communicators, smartphones and portable digital music players. I found the FreeLoader, which cost £30, worked well – especially when I placed it on the dashboard of the car.
Paul Taylor tackles your high-tech problems and queries at www.ft.com/gadgetguru
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