Some energy sources such as diesel can be unnecessarily costly when it comes to pump operation. Fortunately, there’s a solution to this: solar energy. Solar provides reliable energy without any operating costs at all, making it the perfect partner for any water pumping system, regardless of whether it is intended for water production or water distribution.

In this training module, we’re going to introduce you to solar water pumping systems. First up, we’ll introduce you to solar energy in general as well as the typical performance you can expect. After that, we will take a closer look at the main advantages of solar-powered water pumping systems.

Finally, we’ll use a specific example to show how a solar-powered water pumping system can be used to great effect. So, let’s get started.

Using solar as an energy source is becoming more and more popular all over the world, and has been used for a variety of purposes including providing energy for domestic homes and commercial buildings.

Solar irradiation can provide up to 600-1000W/m2 on a sunny day. On a cloudy day, you’ll typically get between 50-300W/m2. But it’s not only the amount of sun that determines performance. The panels are also influenced by temperature. For instance, when the temperature is high, the voltage drops, while the current more or less remains unchanged, meaning that less power is produced.

During a perfect day, you’ll get around 10 hours of sun. However, it doesn’t mean that you get the same level of power during all 10 hours.

For instance, if the sun rises at 6am, the irradiation levels won’t be high enough to power the solar panels. Typically, your solar pumping system will receive the most power between 10am and 4pm when the sun is at its highest.

In terms of powering water pumping systems, solar pumping technology has increased in popularity in recent years. Let’s take a closer look at why that is.
First of all, there’s the cost. The initial cost of solar panels has previously been quite high. But today, the price of solar panels continues to drop, meaning that the payback period is becoming even shorter than previously.

And as the power is delivered by solar, there are no operating costs at all. In comparison, a diesel generator has extremely high operating costs.

Another main advantage of solar water pumping systems is the low level of maintenance.

In fact, the only form of maintenance needed is an occasional cleaning of the solar panels. The diesel generator, on the other hand, requires a high level of maintenance and even demands full attention as it needs to be refuelled on a regular basis.

Next, there’s the environmental-friendliness of the solar-powered system. One of the most obvious advantages of solar technology is that it uses clean, natural energy. Compared to the polluting energy from diesel generators, it’s the most energy-efficient solution by some distance.

Now that we’ve outlined the main advantages of using solar power, let’s turn our attention to how solar water pumping systems work. In this example, we’re going to use a small farm as our starting point. Our objective will be to provide water to livestock, and our pump of choice will be the Grundfos SQFlex submersible pump.

First of all, you have to install the pump in a borehole or a well. The pump will then lift the water to a cattle trough by means of solar power. When the trough is full, the pump is automatically switched off by the level switch signal sent through a CU200 control unit. However, you can also continue to pump water and simply store it in a water tank for later use.

That’s just one example of how a solar water pumping system can be used. Other possible applications include pumping water to remote homes, irrigating fields and delivering water to rural areas, which aren’t covered by grid power.

So, that covers the basics of solar water pumping systems. Let’s go through the main advantages one more time.

Solar panel prices are dropping. Add to the fact that there are no operating costs, the payback period is becoming even shorter.
Solar water pumping systems require little or no maintenance once in operation.
And finally, solar water pumping systems use clean, natural energy.