Solar Water Pumping Module 4 Assessment Test

Final Assessment Exercise.

Using the relevant information in this program, complete a simple design for a solar water pumping system with the following requirements and specification. “Designing” the system in this case includes some assumptions:

Ignore any advantage of using a Maximiser
Ignore any temperature or pressure effects in pumping detail
Use a 20% increase on your calculated “into motor” power to reach estimated rated array power
The pump is suitable for the task and is mated well to the motor.

You are required to calculate within reasonable tolerance a system comprising a DC motor of a certain size (you will choose), and a PV array to drive the motor.

Site details:
Lift from surface water to surface pump 3 metres – adequate water in dam.
Push from surface pump via a pipeline to a tank 6 metres vertically above the pump.
Pipeline is 40 mm pipe class 9, and is 800 metres long.
Peak sun hours at site in design month: 5.0.
Efficiency of motor: 70% ( 0.7).
Efficiency of pump: 50% ( 0.5).

Daily water needs:
700 cattle at 20 litres each per day, plus Gardens, Orchard, Lawns using a total of 3000 litres, and 20 people at 50 litres each per day in a domestic situation every day.