Page 302 - Applied Photovoltaics

F.6 WIND PUMPS
Advantages:
x relatively mature renewable energy technology when used for stock watering
x low cost in areas with adequate wind regimes
x zero fuel costs
x suitable for local manufacture
x relatively simple maintenance needs.

Disadvantages:
x not yet well developed for irrigation purposes
x moderate output, fluctuating with wind conditions
x critically site-dependent.

F.7 WATER WHEELS, TURBINES, RAM PUMPS AND CURRENT
TURBINES

Advantages:
x low cost, long life, low maintenance, fuel-free power source if suitable site
conditions are available to exploit water power.
Disadvantages:
x depends on relatively rare site conditions, which limit the areas that could
benefit from this type of prime mover.

F.8 STEAM ENGINES
Advantages:
x potentially low cost renewable energy technology, especially if agricultural
waste can be used as fuel.
Disadvantages:
x fuel requires land use or transport of coal
x steam engine technology is generally obsolete, while modern equipment is
not readily available
x safety problems with boilers
x constant or frequent attendance needed.

F.9 BIOGAS-FUELLED SMALL ENGINES
Advantages:
x allows the advantages of small engines, described above, but is independent
of supply of petroleum fuel
x immature technology for biogas production, but has low-cost potential
x fertiliser produced as a by-product from the digester.
Disadvantages:
x includes most disadvantages of small engines (spares, maintenance etc.)

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