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SOLAR POWERED CARS



V. Ryan © 2006

Solar cars have been developed in the last twenty years and are powered by energy from the sun. Although they are not a practical or ec**omic form of transportati** at present, in the future they may play a part in reducing our reliance ** burning fossil fuels such as petrol and diesel.
A solar powered racing car is shown above. These are expensive to produce and usually seat **ly **e or two people. The main cost is due to the large number of expensive and delicate photovoltaic solar panels that are needed to power the vehicle. Also, many of the solar powered cars used in races today are composed of expensive, lightweight materials such as titanium composites. These materials are normally used to manufacture fighter jets. Carb** fibre and fibre glass are also used for much of the bodywork. Most of the cars used in races are hand made by specialist teams and this adds to the expense.
A solar powered vehicle can **ly run efficiently when the sun shines, although most vehicles of this type have a battery backup. Electricity is stored in the batteries when the sun is shining and this power can be used when sun light is restricted (cloudy). The batteries are normally nickel-metal hydride batteries (NiMH), Nickel-Cadmium batteries (NiCd), Lithium i** batteries or Lithium polymer batteries. Comm** lead acid batteries of the type used in the average family car are too heavy. Solar powered cars normally operate in a range of 80 to 170 volts. To reduce fricti** with the ground the wheels are extremely narrow and there are usually **ly three.
Some solar powered cars are practical and **e is shown below. This is a solar powered golf cart and it can be used in sunny climates to carry golfers from **e hole to the next. When it is standing still the solar panels charge up the batteries and it is the batteries that power the electric motors, directly. As the vehicle is not in c**tinuous use the batteries have time to charge up before they are needed.


**e of the **** realistic ways in which that solar powered cars could become practical is to charge up their batteries when they are parked, during the day. Imagine driving the short distance to work and plugging the car into a set of photovoltaic solar panels. Whilst you are working the batteries charge up ready for use for the journey home. The same procedure could be carried out when the car is parked at home. A combinati** of solar power and wind power may prove to be a method of charging the batteries of ‘electric cars’.