In households with a swimming pool or spa, the pump is usually the largest user of electricity, making up about 18% of the electricity bill. Over its lifetime, a pool pump will use a lot of electricity.
If you own a single-speed pump, electricity will cost much more than the initial purchase price of the pump. You can save money on your electricity bill by buying a more energy-efficient pump, even if it costs more upfront*.
Swimming pool pumps are required to undertake a range of different tasks aside from general filtration. These can include vacuuming, backwashing, and running special applications such as water features, spa jets all of which require higher flow rates and pressures, however, they’re not required all the time.
90% of the time the pump is used for filtration and water circulation only which can be achieved with relatively low water flows using a lot less energy. This is where a variable speed pump will save you money.
There are two main types of variable speed pumps
The Astral Viron XT Variable Speed Pool Pump
Multiple Speed pumps are only capable of a number of fixed speed options, usually low, medium & high.
e.g. Low RPM for general filtration, medium or high RPM for manual vacuuming & then high RPM for backwashing.
Therefore, a multiple speed pump provides 3 pre-determined fixed speeds to choose from whereas the fully variable is fine tuneable to your exact requirements.
Fully Variable Speed pumps such as the Astral Viron Range, are able to operate at any number of speeds within their range, usually based on an RPM. The controller will allow the increase & decrease of the motor speed and therefore water flow throughout the system to suit the intended application.
And the actual energy used to change the speed and flow reduces dramatically because of the Pump Affinity Law. This law states the power requirement varies by the cube of the change in speed so reducing the RPMs of your pump by 50% creates an energy saving of 75% compared to a conventional single-speed pump*, so small savings in speed equate to large savings in energy.
Not only do Variable Speed Pumps use less energy when set to a lower speed, but they also lower the flow rate and a lower flow rate takes the pressure off the pool plumbing and other equipment, which in turn increases the service life of the equipment and further reduces future maintenance costs.
Lower speed also improves filtration efficiency leading to a clearer pool and as it does not drive the dirt as deep into the filtration bed backwashing is more efficient.
Lower speeds means less noise too, so you can run the pump overnight to benefit from off-peak electricity and your neighbors will thank you too!
Finally, it enables the automatic chemical dosing units and salt chlorinators to operate more effectively – again saving on maintenance costs for your pool.
Cons to variable speed pumps?
It does however reduce the amount of water going through the filtration system so it takes longer to turn over the pool water, and so in warmer weather or when there is more use of the pool, a longer run time will be required to filter the pool water but this increase in run time will be more than offset by the savings in power.
All in all the use of a variable speed pump is a very good investment for your pool, your power consumption, and the planet.
Contact us today to find out which variable speed pool pump is right for your pool.
*source: energyrating.gov.au, canstarblue.com.au