Solar cells are used to transform the energy of the sun into electric current. The electromagnetic emission from the sun is directly converted into electric current. The transformation happens in a specific way. When the sunbeams are absorbed, electrically charged particles are formed which are then forced into moving by the electric field generated by the solar cell, creating electric current. This process can be triggered by several other light sources that has a matching spectrum, thus not limiting the process only for the sunbeams.
Solar cells are very sophisticated equipment and come with a 25 years warranty but their usual lifespan is 30-40 years.
It is generally accepted that their use will be increased in the following years.
Basic types of solar cells:
- Monocrystal solar cell. Their primary ingredient is silicon (Si) They are one of the best price-value classification in the market of solar cells. Their greatest efficiency is 18%, but researchers were able to achieve 25% in laboratory environments.
- Policrystal solar cell. Their primary ingredient is silicon.
- Gallium-arsenide solar cell: Premium classification, very expensive. Their top efficiency is around 40%, which makes them very valuable, especially in space technology. They are mainly used in space research.
- Amorphous silicon solar cell: Cheaper than most other types but their efficiency is only 5-8% Less silicon is used during production.
- Polymer solar cell: Quite cheap but only has an efficiency of 3%.
- Organic dyed solar flare: The cell is covered with light-absorbing paint which has electro-chemical properties. Its cheapness is its biggest value, but its efficiency is around 2-4%.
- Other types of chemical and semi-conductor solar cells: Their prime ingredients may vary, but their efficiency is mostly under 15%.
Raising the efficiency can be achieved through multiple ways but this requires more complex and expensive technology and equipment. Raising the efficiency can’t be done infinitely. The highest amount for 1 solar cell is 33.7%. This can be increased only by applying several thinline solar cells on top of each other. This way, they are only sensible for the given wavelength of electromagnetic emission. This wavelength decreases after every single cell. Further improving of the efficiency can be achieved by applying bigger concentration and amount of light using special lens and mirrors. Research and development today focus more on the price-value factor of the solar cells and not the increasing of efficiency. The aim is to reduce the time from which the production cost is smaller than the profit.