Page 159 - Applied Photovoltaics

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Figure 8.6. Typical unit water costs as a function of pumping head for 40 m /day
average pumping output (Used with permission of Halcrow & Partners, 1981).

It is imperative that systems be designed specifically for the application. The system
configuration, component types and their respective sizes are influenced greatly by
such aspects as water source capacity, water source replenishment rate, water volume
required per day, solar insolation availability, pumping time/flow rate, static water
level, draw-down level, discharge head, seasonal head variations, pipe size and
friction, and pumping subsystem component characteristics and efficiencies.
Information on each of the above needs to be known to facilitate proper system
design. In addition, as shall be seen in Chapters 11 and 12, careful matching of the
pump, motor and photovoltaic arrays is essential. Fig. 8.7 indicates the losses in a
typical photovoltaic-powered pumping system.

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