SOLAR PUMPING- Key Aspects and Options

Do you have a well or borehole, or another type of reservoir and want to pump water from it at low cost?? Do you have an electric pump, and want to save a few dollars on your ZESA bill or perhaps you want a reliable source of energy, or better still you want to use BOTH solar and grid electricity to power your pump?? Then solar pumping is the answer for you!! Solar-powered pumps use electricity generated by solar PV panels to power pumps which then pump water to a reservoir (tank) or some piping reticulation. Solar powered pumps have low operation, maintenance and running costs, and are more friendly to the environment as they use a renewable energy source.

Components of a Solar Pumping System

A solar pumping system consists of 3 main components:

• 1. Solar Panels- convert solar energy into electrical energy that that can be used by the pump.

• 2. Pump Controller- has 2 functions: (i) it matches power that goes to the pump with the power that is available from the solar panels. (ii) the better quality controllers have an additional function of providing voltage protection for the pump- it basically switches off the pump if the voltage is too low or too high for the operating voltage range of the pump [1]. The better quality controllers also offer further protection for the pump by turning off the pump when the level of water in the well/borehole is too low. The more modern controllers can also provide options for monitoring the system performance online

• 3. Pump- moves the water from the water source (which can be a well/borehole/reservoir), to a point if use or storage. An electric motor drives the pump, and the motor is powered by the solar panels

Can a pump operate using BOTH grid/generator electricity and solar power??

This is a common question we get from customers who have an existing electric pump and want to make use of solar during the day, and grid/generator electricity in the night. The good news is yes it can be done!! All that is needed is to install a pump inverter and PV panels. Remember solar power from panels comes in as Direct Current (DC), and the purpose of this inverter is to change the DC to AC that can be used by the pump during the day, with a function to allow AC power when the sun goes down.

So what are you waiting for??? GO SOLAR!!!

Next post we look at how to size and select a solar pumping system.

Sources:

1. https://en.wikipedia.org/wiki/Solar-powered_pump

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About Author:

Lovewell Chitiyo is a Mechanical Engineer with 15 years experience in the building services Engineering consultancy, renewable energy systems and sustainable design fields. He is currently studying Masters in Renewable Energy at Stellenbosch University in South Africa

Lovewell is an Accredited Professional with the Green Building Council of South Africa for Existing Buildings Performance and New Buildings; Interiors, holding several qualifications and certification in Renewable Energy and Sustainability.

Lovewell also has vast experience in design, supervision, installation and commissioning of several projects locally and regionally in the last 15 years.