From the perspective of utilizing wind energy, using two blades is the best. However, there is a disadvantage that the vibration generated by the fan during operation has a great impact on the service life of the fan. Three blades can be a good solution. This problem. The disadvantage of three blades is that its wind energy utilization rate is not as good as that of two blades. But weighing the pros and cons, I still use three blades.
The installation and transportation costs of 2-blade blades are lower than those of 3-blade blades. In addition, the tip speed ratio of the 2-blade is higher than that of the 3-blade. If it is used to generate electricity, the speed increase ratio of the gearbox is smaller than that of the 3-blade, so the cost of the gearbox is less.
ps
The hub structure of the 2-blade is special, with a seesaw structure, and the fatigue problem is more serious than that of the 3-blade. So each has its pros and cons.