Vehicular emissions are one of the major contributors to pollution in urban areas. With rapid growth in urbanisation, the number of vehicles in Indian cities has grown manyfold, leading to increased congestion on roads as well as a concentration of harmful gases emitted by vehicle exhausts. To combat the increasing pollution levels, many companies have come up with electric vehicles (EVs) that run on batteries. EVs not only reduce the dependence on conventional fuels like petrol and diesel but also help in the reduction of emissions. However, some contend that EVs are not very environment friendly because the ultimate source of charging the batteries may be conventional power.
In order to reduce the dependence of vehicles on conventional fuels, researchers at the Anna University, Tamil Nadu, have developed a prototype of a solar-assisted bicycle. The design of the solar bicycle comprises a brushless DC motor mounted on the front wheel, an electric throttle for varying the speed of the bicycle and a lead-acid battery that stores solar energy produced by the solar panels mounted on the bicycle carrier.
The brushless hub motor has an array of permanent magnets placed on its inside surface. The motor’s two windings are attached to the front axle and the alternating current produced by these windings helps rotate the hub and thereby, the wheel of the bicycle. The bicycle has also been provided with an accelerator, which is used to run the motor at different speeds by changing the battery voltage to alternating voltage with varying frequency and amplitude. A solar panel has been mounted on the carrier to produce electricity, which gets stored in the lead-acid battery. The researchers have used a lead acid battery as its efficiency level, performance and standby time are best suited for such an application. The bicycle works on the principle that when power supply is given to the hub motor from the solar panel unit, the bicycle wheels rotate. The bicycle rider can choose either a motor or pedal, or both at the same time.
While only a prototype of the bicycle has been developed so far, the researchers are confident that a commercial model can be made available in the market by 2018. When it hits the road, the bicycle is expected to cost around Rs 12,000-Rs 15,000. The bicycle can be customised according to the needs of different customers by changing the power rating of the motor and installing higher capacity solar panels for higher speeds.
The solar bicycle solution needs adequate support for ensuring its widespread uptake. The government can explore monetary support measures to make it more affordable. Moreover, people have to be made aware of the extent of environmental damage caused by vehicular emissions and the potential of solar bicycles in negating it.