“SOLAR ENERGY”

by

Farooq Raza Qadri

Today in Pakistan we are facing shortage of almost every basic need of life like water, gas, and especially electricity. It is the worst conditions we are facing now a days. The reason for that is…well we all know “THE REASONS” don’t we!!! Few days back I was reading an article in a local newspaper which was about getting electricity like many European countries which is from “Wind Turbines”. It’s a very good idea and we must have to think other ways of energy to meet our needs. Another idea which I’m going to discuss here is “SOLAR ENERGY”.  As we all know that summer season is longer than winter in Pakistan. So it means we can get more and more sunlight. In my view Solar Energy Systems will be more successful in Pakistan than any European country because thankfully we can have more sunlight than Europe. Many scientists and engineers from all over the world are working in this field. Some say that it’ll be very costly, YES it’ll be but only in start as like everything when it’s new its price is high but when the competition arises then prices goes down its simple economics. We've used the Sun for drying clothes and food for thousands of years, but only recently have we been able to use it for generating power. The Sun is 150 million Kilometers away, and amazingly powerful. Just the tiny fraction of the Sun's energy that hits the Earth (around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over. In fact, every minute, enough energy arrives at the Earth to meet our demands for a whole year - if only we could harness it properly and preserve it.

Here are some techniques that are being used in many parts of the world to get energy from the sun light.

Solar Cells(really called "photovoltaic" or "photoelectric" cells) that convert light directly into electricity. In a sunny climate, you can get enough power to run a 100W light bulb from just one square metre of solar panel. This was originally developed in order to provide electricity for satellites, but these days many of us own calculators powered by solar cells. Solar cells provide the energy to run satellites that oribt the Earth. These give us satellite TV, telephones, navigation, weather forecasting, the internet and all manner of other facilities

Solar water heating, where heat from the Sun is used to heat water in glass panels on your roof. This means you don't need to use so much gas or electricity to heat your water at home. Water is pumped through pipes in the panel.
The pipes are painted black, so they get hot when the Sun shines on them. This helps out your central heating system, and cuts your fuel bills. However, in very cold places especially in winter season you must remember to drain the water out to stop the panels freezing. Solar heating is worthwhile in places like California, Australia, South East Asia (Pakistan, India, Bangladesh) where you get lots of sunshine as I mentioned it earlier.

SolarTowersOne idea that is being considered is to build Solar Towers. The idea is very simple - you build a big greenhouse, which is warmed by the Sun. In the middle of the greenhouse you put a very tall tower. The hot air from the greenhouse will rise up this tower, fast - and can drive turbines along the way. This could generate significant amounts of power, especially in countries where there is a lot of sunshine and a lot of room, such as Australia.

Advantages

• Solar energy is free - it needs no fuel and produces no waste or pollution.




• In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.




• Handy for low-power uses such as solar powered garden lights and battery chargers

• Doesn't work at night. (Positively thinking it’ll cut our huge fuel and energy bills into half if we even have the solar energy system in day time. So that’s make it a negligible disadvantage.)




• Very expensive to build solar power stations.
  Solar cells cost a great deal compared to the amount of electricity they'll produce in their lifetime.




• Can be unreliable unless you're in a very sunny climate. In the United Kingdom, solar power isn't much use except for low-power applications, as you need a very large area of solar panels to get a decent amount of power. However, for these applications it's definitely worthwhile.