Multijunction solar cells
Posted by Solar energy guru | Filed under Solar panels & photovoltaic cells
Single layer solar cells are not very efficient and are not an optimal option for solar cells. This is mostly due to the fact that they are not capable of converting all light into electricity. Without going into too much detail, a single layer solar cell is only capable of converting light which more energy than the band gap in the solar cell. With all this said it is important to choose an alternative that is more efficient at converting direct light into electricity and that is where multijunction solar cells are a great choice.
Multijunction solar cells utilize the solar spectrum more sufficiently as there are many semi conductor layers located in various band gaps. For multijunction solar cells to absorb as much light as possible it is designed with different materials in different layers. Typically a multijunction solar cell would consist of a III-V semi conductor for each layer. Every different layer of the solar cell is absorbing a different part of the solar spectrum so instead of just getting part of it, you basically absorb all light and convert it to electricity.
Triple-Junction Solar Cells
While there are different designs of these solar cells the most common one is made up of three different layers. This particular solar cell may also be referred to as a triple-junction solar cell. It is designed with III-V semi conductors, as all multijunction solar cells should be, and offers a much higher efficiency than most alternative solar cells.
A triple-junction solar cell, or any multijunction solar cell for that matter, is much more effective than any single layer solar cell. To further prove this point just take a look at the world record for highest efficiency of a solar cell, it just so happens that the top three slots are all occupied by triple-junction solar cells. The only downfall to a triple-junction solar cell is that it can be much more expensive than the alternatives.
Advantages and Disadvantages of Multijunction Solar Cells
It should already be obvious what the main advantage of having multijunction solar cells would be. The most important thing when looking for solar panels is how efficient they are. While you may be shopping on a budget you will still want to choose the right solar panel so you get the best results possible. The most important deciding factor on how efficient your solar panel would be is the efficiency of the solar cells. With multijunction solar cells it is not difficult at all to get a efficiency rating of 35-40% and no other type of solar cells could match this.
As it has already said, multijunction solar cells can be rather expensive and may not be within your budget. The main reason why these solar cells are more expensive then the alternatives is because of the materials that are used during production. The materials used to make multijunction solar cells are much more complex than those for other types of solar cells. As a result of this, it is best investing in when you must convert a massive amount of direct light to a small section of solar cells.
A cheaper alternative would be the silicon solar cells which only use inexpensive materials but this is almost the exact opposite of multijunction solar cells as with the price decrease, the efficiency is much lower as well. Conclusively, multijunction sollar cells are definitely the most efficient option to this day but since they are still priced rather high it may be best to only use multijunction solar cells in collector cells. However, it is easy to conclude that these solar cells are definitely the most efficient solar cells to be discovered so far.