We can know from this formula that: 1. If the wind speed is a constant, then m P is in proportion to R2 (R is the radius of wind-wheel,) that is to say, for getting higher output power, the wind-wheel need the largest radius as possible, or say the largest area the wheel blade can get. But big size wind-wheel will make the increase of the cost and the difficulty of install of the wheel. 2. If the radius of windwheel R is a constant, P is in direct proportion toV 3 , so the wind generators should be installed in the areas with high wind speed, which relates to the environment. In the same position, the higher altitude, the higher wind speed will be, hence the tower-shelf should have a comparative altitude. 3. The wheel power is independent of the numbers of wheel lamina, but is in direct proportion to the air density. 4. The biggish wind energy power available coefficient p C , can improve the wheel power.