Among the oldest forms of renewable energy, solar energy is the most used. In fact, it is the first to be used by the mankind. Solar energy is not just renewable but is also clean, in the sense that it does not pollute the earth. The amount of energy transferred from sun to the earth in one hour is enough to charge up the earth
for a whole year. The problem is to tap this vast amount of energy properly.
Sun’s energy can be tapped in two ways. It can be tapped by collecting its heat or by converting its light into electricity. There are two types of solar energy, known as Passive Solar and Active Solar. Active Solar energy systems use solar panels and other devices to tap the sun’s energy. The panels are fitted in such a way that it maximizes the exposure to sun. The active systems of solar energy are more expensive and complex to use.
Passive systems do not involve the usage of any devices. It involves planning and developing the structure in such a way that the energy of the sun is captured in the best way.
The energy can be collected by proper positioning of windows, tanks and so on. The new innovations and better technologies have led to increased awareness among the investors, mobilizing huge solar thermal investments.
Subject: Active and Passive Solar Energy 
