With most people today using one or more cell phones the energy these devices collectively consume is huge.
Although it would be impossible to expect people to minimise phone use, they can certainly opt for green energy resources for charging their cell phones.
Solar energy is perhaps the most widely harnessed among alternative power sources for almost all devices including cell phones.
There are two variants of solar chargers available in the market. Of them, one powers the device directly and the other comes as a battery pack that can be charged in the sun and can later be used to power devices.
The biggest challenge with solar cells is their low charging current which might not be abundant for new generation mobile phones, which consume a lot of battery life, but this is fast changing as new technology employed in the making of solar cells allows them to gather energy faster than they used to a couple of years ago.
Solar chargers are also small in size, which makes them extremely portable. They can be left on the car’s dashboard while driving and an hour in the sun is enough to power any cell phone for an equivalent period of standby time or for a short while of call time. Besides, these chargers can be used again and again.
A new type of solar cell has also been developed specifically to charge cell phones and gadgets. It is made of a flexible material as opposed to conventional glass, which can be woven into wearable fabrics like a t-shirt.
In India, popular websites like eBay have special sections for solar cell phone chargers.
Kinetic energy chargers
Motion energy too has huge potential and, unlike solar power, it can be tapped in the day or at night as well. A kinetic energy charger is a small device with a moving magnet around a coil, which produces energy. Such chargers can be used while walking, exercising, running, jogging — wherever there is motion.
Mobile manufacturer Nokia has developed a cell phone charger for bicycle riders. The charger uses kinetic energy. A small dynamo attached to the moving tyre of a bicycle powers a charger, which in turns provides the energy to charge the device at a rate comparable to that of a wall charger.
Another popular and well tested kinetic energy charger is a crank up charger, which is widely available in the market. These chargers also have miniature dynamos inside them, which are powered by physical movements of the hand.
With the advancement of technology these hand cranked chargers have become small enough to be carried easily inside a purse or even a pocket. They are efficient enough to power a device or can restore the battery for an emergency call within seconds.
Wind powered chargers
Many companies have already announced products that utilise wind to charge mobile phones. One such charger is Miniwiz made by Hymini.
Miniwiz is a portable wind based turbine that is small enough to be carried around. It can be used while driving or wherever there is wind.
Technology has made these devices so small that they easily fit in the palm of the hand and have enough power to run gadgets for long periods. The portable windmills power the battery, which in turn charges devices or can be used to store charge for later use.