Harnessing Solar Energy

Who say's religion and science can't mix? Well apparently, some aspects do as recent news from the Vatican indicates. In less than two years, we will see some of the Vatican buildings using solar energy for illumination, heating and cooling.

Pope Benedict XVI is a known environmentalist. The planned energy conversion is seen as part of the Pope's action about conserving the Earth's natural resources. For the planned solar energy conversion, the Vatican engineer will be replacing the cement panels of the roof of the 6,300-seat Paul VI auditorium with photovoltaic cells. The auditorium is rarely used. It's used only during winter and in bad weather.

The move by the Vatican to use solar energy is laudable. Harnessing the sun's radiation is a safe and efficient way of producing energy. If you thought that using solar energy is a new innovation, then you're wrong. The sun's energy has been harnessed by humans before. Early humans even worship the sun as a God. We have come to know sun-gods like Ra, Shamash, Apollo and Helios.

Nowadays, however, people use the sun for heating water, building heat, cooking, electricity, transportation and desalination of seawater, all through the help of what we call photovoltaic cells.

Photovoltaics is a technology used to convert light energy into electrical energy. It is used more commonly in solar cells which we are more familiar with. The photovoltaic cells will convert light into direct current electricity. At first, the cells were used to power orbiting satellites and portable calculators. Today, however, the cells are stronger and more reliable to be used for larger power generation.

The first solar cell was built in 1883 by Charles Fritts. His solar cell was a gold-coated semiconductor selenium one. Not surprisingly, Fritts' solar cell was not that efficient, it was 1% efficient, actually. It was in 1946 that Russell Ohl patented the first "modern" solar cell. And it was only after eight more years that true solar power technology began. It was at this point that Bell Laboratories found that silicon infused with certain impurities was very sensitive to light.

Solar energy or solar power can be classified in a number of ways. It can be classified as direct or indirect which refers to the way sunlight is transformed into a usable form of energy. By direct transformation, we mean that solar power is converted by a single transformation process. Indirect, obviously, involves multiple transformations of sunlight.

Solar energy can also be described as passive or active. Passive refers to the use of various non-mechanical means to capture and covert solar radiation into energy humans can use. Active solar energy, on the other hand, uses electrical and mechanical components to convert solar energy.

Concentrating or non-concentrating is another way of classifying solar energy. Concentrating solar energy uses mirrors and tracking devices to focus the sun rays on a specific point to create boiling hot temperatures which can be used for thermodynamics. Non-concentrating photovoltaic solar energy does not concentrate sunlight.

The problem with solar energy is that is can be quite expensive to set the whole system up. Plus, solar energy is not available during night time or during bad weathers. It is, therefore, necessary to use a type of storage device so that solar power can be utilized more efficiently.