Applications and Wind Industry - Wind Energy: Renewable Energy and the Environment - page 210

FIGURE 10.6 Schematic diagram of the American farm windmill.
The Agricultural Research Service, USDA, and the Alternative Energy Institute, WTAMU, have
tested some of these concepts in their cooperative program on wind energy for rural applications
[38]. A company in South Africa has a windmill with a rotating helix pump [39].
Costs can be reduced by using local materials, local light industry manufacturers, and new
windmills designed for developing countries. One option is the use of the Savonius rotor for low-
volume, shallow water. Another option is a wind turbine driving an air compressor and an airlift
pump. However, the problem is still the same: the rotor is connected to a constant-torque device.
10.6.1 D ESIGN OF W IND W ATER P UMPING S YSTEM
The requirements for the various applications differ in that water for livestock and residences is
low volume with a storage tank, while villages require potable water with a storage tank for low or
high volume, depending on the size of the village, and irrigation requires large volumes and gen-
erally does not need a storage tank. The steps to consider in designing or sizing a water pumping
system are:
1. Water demand: livestock, residence, village, irrigation
2. Water resource: surface, well, volume available