It is important to remember that the load is part of a wind energy conversion system (Figure 8.1). The most common application is the generation of electricity—a good match of the characteristics of the rotor and the load. The other major application for wind power is pumping water, which is a poor load match when the rotor is connected to a positive displacement pump (constant torque device). However, a farm windmill is well designed to pump low volumes of water with a positive displacement pump, even though it is inefficient.