Wind Power Generation - Renewable Energy: Technology, Economics and Environment - page 335

Common tower heights of small wind energy converters stretch from several
metres up to approximately 30 m. Towers are often of simple design, e.g. lattice
work or guyed tube towers.
The described energy supply systems are applied in the windy areas of devel-
oping countries (particularly in rural areas lacking power connection) as well as in
industrial countries (in case retrofitting of grid connection is too expensive).
Typical applications include lighting of remote sites, energy supply for communi-
cation facilities or signals on freeways, power supply to remote huts and houses.
Further areas of application are battery-charging systems of vessels, power supply
for electronic fences or cathodic corrosion protection.
In the meantime also larger wind-battery systems have been developed that
may be connected to the power grid to ensure supply of a determined minimum
capacity within periods of low wind availability and to compensate for fluctuating
wind flow.

Wind pumps. Wind pump systems are sub-divided into systems equipped with
electric and mechanical pumps.
Wind pump systems equipped with electric pumps first convert wind energy
into electric energy and subsequently reconvert it into mechanical energy. They
are usually applied for high capacities. Standardised wind turbines may be used.
Thanks to the isolation of the mechanical energy of both wind rotor and pump, the
pump location is entirely independent from the wind energy converter location,
which is advantageous in many cases, as irrigation systems are often located in
valleys and areas where there is little wind.
Mechanical wind pumps directly convert the kinetic energy contained in the
air into mechanical pump energy without energy being first converted into electric
energy. Fig. 7.23 shows such a system. Typical fields of application include pota-
ble and livestock water supply as well as irrigation and drainage.

Wind pump system Wind pump system

Wind pump Wind pump Hydraulic device Hydraulic device

Energy Energy Windmill Windmill

Water
storage

Water
storage

Hydraulic
energy

Hydraulic
energy

Losses Losses

Power
transmission

Power
transmission

Delivery
side pipe

Delivery
side pipe

Pump Pump

Well Well

Fig. 7.23 Irrigation system using wind energy