In the market place today there are three basic types of solar cells. Solar cells are more commonly referred to as photovoltaic modules. The three basic modules are single crystal silicon, polycrystalline silicon and thin film.

Single crystal silicon was first created by accident in Bell laboratories in 1954. An experiment using semiconductors had a silicone doped with impurities which showed a sensitivity to light that was greater than ever seen before with other materials.

The efficiency was only at 6% but it was promising. Eventually the efficiency would reach 33% but has leveled off since then without an increase. The major drawback was that each solar panel was just one crystal. If just part of it becomes damaged then the entire cell will not function properly and the costs are extremely high.

In 1981 polycrystalline silicon was developed. This was made out of the same material but poured out into a mold to form the final structure that was wafer thick. They were made square to make a more efficient use of space but upon cooling the crystalline structure would form random crystal boundaries which in turn slightly reduce the efficiency of energy conversion to about 20%. These could be easily placed in conjunction with other cells to form panels. This is the most common of all the solar cells in use today.

The last is thin film panels that are made of the same material as the polycrystalline cells but microscopically thin. These are more flexible than the polycrystalline panels and were finally put into production in 2007. The production costs are lower than polycrystalline cells but they have yet to attain the same efficiency. Of the different types of solar cells the thin layer film is the most promising for higher efficiency.

There is much research being done on improving solar cell efficiency and in how to reduce costs of production.  Refer to earlier articles here on way to go green below.

There are currently three different types of solar cells in production in today’s market place. There are the monocrystalline, polycrystalline and amorphous.  There are differences between the three and knowing the difference will help the consumers make a better choice on which type is best for them.

First there is the monocrystalline cell, which is made from a single large crystal, usually cut from one large man made ingot. This is difficult to handle and if broken then the whole cell has to be replaced. Since it is one piece there is no resistance thus being the most efficient. It is even efficient in low light conditions.  This cell has a major draw back of being the most expensive to manufacture.

Second there is the polycrystalline cell, which is made from many small blocks. This is less expensive to manufacture since it is smaller and easier to handle. Connecting all the cells together does reduce the efficiency but not a great deal.

These first two are the most common and most efficient at about 33%. In addition with the high cost of production, it is not possible now to see a further reduction in the cost, which is about $1 US per watt.

The last is amorphous cell. This is sometimes referred to a thin layer or second generation. This has good and bad to it.  This cell is the cheapest to manufacture thus being the least expensive to purchase but also the least efficient.

There are other types of solar energy panels but for photovoltaics these three different types of solar cells will be your choices for your solar power system.

With the first two using silicon and the last one using cadmium or copper, the price of the raw materials will be the driving cost in finished cost of the cells. Make your choice a wise one just remember if you chose the thin cell it will take more of them to produce the same amount of energy as the silicon based cells.

Researchers at the University of South Florida have built some of the tiniest solar cells ever made from organic material and they can be applied like paint on to surfaces.

They have pulled 11 volts of electricity from a small array of the cells, which are each just a quarter of the size of a grain of white rice.

They could be sprayed on any surface that is exposed to sunlight, like a uniform, a car, or a house.

Because it is in a solution, you can design a special spray gun where you can control the size and thickness.
Most solar cells are made up of silicon wafers, a brittle substance that limits where they can be placed.

The main components are carbon and hydrogen — materials that are present in nature and are environmentally friendly.

Published in the Journal of Renewable and Sustainable Energy.