The Tribune

By Joshua Key, Green Solutions

We’ve barely reached the end of May, and already it feels like summer is in full swing. This means that, after spending the winter months as far away from frigid pools as possible, many Bahamians are making the annual migration back into the water.

This, in turn, raises the issue of the pool pump. How many hours will I have to run it to keep my pool clean? And how much will it raise my electricity bill? With these questions in mind, it is worth considering whether an upgrade to a solar pump for your pool, or even for your whole home, is a good investment for you.

When it comes to solar pumps, there are two main options:

* Upgrade to a solar pump, or

* Pretend to upgrade to a solar pump. Believe it or not, most of my clients pick this option.

Consider Option one; upgrading to a solar pump. How does it work? Let us take the pool, for example. To convert to a solar pool pump, we would remove your current pump and replace it with one designed to work directly with solar power. Then we would install solar panels and controllers, ideally as close as possible to your pump. The wiring would be run, connections established, and fasteners secured. Finally, we commission your system.

From this point on, your pool pump runs completely for free. In fact, a pool is an ideal use for a solar pump, because a pool pump only needs to run during the day. In other words, we can design the system so that enough water is pumped during daylight hours to keep the pool clean day and night. Thus the pump does not need to run when there is no sunlight to produce power.

If you want to use solar power for a pump that does need to run at night, such as your home water pump or a pump for a decorative fountain, then upgrading to a solar pool pump becomes more complex and costly. In addition to all the steps and materials above, your system will require batteries to store power for use at night.

Further, your system will have to be somewhat oversized. Why? You do not want your plumbing to stop working. For example, if you have guests visit, and the pump has to run much more than normal, or if we have several cloudy days in winter, and much less power is available than normal, your solar system will still need to power your pump. Running pumps at night is not an ideal situation for small solar systems.

Of course, you can alleviate some of these issues by getting a solar pump that can connect to Bahamas Power & Light (BPL) for power sometimes, but paying BPL to run a solar pump is not ideal either.

If you want to upgrade to a solar pump, how can you recognise a quality one? In the Bahamas, you want a pump with non-corrodible materials used throughout. Check whether any pump offered to you uses a DC brushless motor, as this is more efficient and designed to tie directly to solar power, saving you labour costs. An automatic controller to monitor the system and pump speed should also be included. It will be a distinct advantage if your pump includes MPPT technology to maximise power from the solar panels. Finally, the old adage: ‘You get what you pay for’, certainly applies.

As with any solar system, you want to make sure you use a licensed professional who calculates your solar system’s energy with proper modelling software. After all, there is no point getting a solar pump if you get the wrong type of panels, the wrong number, or they are not configured correctly. This is even more important if your are looking to use the sun to power your whole property. Solar-powered electricity is a technical field. Be sure to work with quality specialists who know their stuff and calculate correctly.

How much money does a solar pump save you? A small 1 horse power (HP), regular pool pump can consume almost 14 kWh (kilowatt hours) per day. That works out to about $1,585 a year that a solar pump would save your on your electricity bill. A slightly larger 1.5HP pump would save you almost $2,000 per year. You save even more money if your pump is larger. It only takes a few years of those savings for your solar pool pump to pay for itself.

In our next article, we will discuss the second option for a solar pump upgrade. In the meantime, if you are interested in saving on your electricity bill this summer, talk with your energy efficient products expert. They can help you choose a green solution that matches your budget and your unique situation.

• NB: Joshua Key is general manager for SuperGreen Solutions Bahamas, located on Wulff Road next to FYP. SuperGreen Solutions is one of the premier advisors, suppliers and installers of domestic and commercial energy efficient solutions.