Solar tracking systems are available in the form of single axis tracking systems as well as duel axis tracking system. The tracking systems add an incremental generation of the order of 10-25%. While it is important to have an extra yield through the tracking systems, it is equally important to understand the complexity of the system through introduction of solar tracking systems. The solar tracking system in a solar field makes the structure more vulnerable the the wild loads and the structure design should be much more robust to withstand for 25 year lifetime of the system. Extra energy yield and the system instability are the two trade offs a system designer has to consider while selecting a tracking systems. Typically the tracking can be classified in to three categories.
a. Seasonal tracking system (generally single axis)
b. Single axis tracking system
c. Double axis tracking system.
As a part of our system design we have done analysis of the different tracking systems on PVSYST and understand how much extra yield can be made through introduction of a tracking system. The results are as follows:
Fixed tilted plane = 17201 MWh
Seasonal tracking system= 17311 MWh
single axis tracking system= 18239 MWh
Double axis tracking system= 23166 MWh
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Since all tracking technologes are different and there are different variations, for example even in Single axis tracking… there are no of ways different manufactures provide tracking. Some can vary only 10 modules with one motors while other can have more (even >10,000) with one motor, there are diffrent gear boxes, bearings, auxilliary consumption and seasing of the components used…. Further all modules doesn’t give the same performance on tracking, some modules are delicate and not suitable to be mounted on modules!!
That’s why it really a technical subject for thorough analysis which needs to be done for every case, every site, every combination….. and thus no genarlised openion can be created.