Selling energy efficiency in pools and spas

Powermasters' Integrated Water
and Energy Management System (IWEMS®)

Psychologists understand very clearly that people don’t always do the things that are in their own best interests. We don’t always eat healthily for instance and we don’t all exercise frequently, because curling up on the sofa is much more comfortable. Less understandable is the evidence that, in our professional lives, we routinely choose to not reduce the energy expenditure required to run the pools and spas we design, build, manage and service. Here, Geoff Renshaw, a director of Powermaster the energy saving technology specialist for pools and spas, argues that this is unjustifiable, given that a typical swimming pool can cost around £30,000 per year to operate in energy bills alone.   

Here’s a shocking fact; it is possible to use existing and proven energy saving technology to reduce the energy consumption of a swimming pool or spa and the building that houses it by up to 82%. If you were still sitting in the couch, metaphorically speaking, when you started reading this article let’s hope you have just laced up your running shoes, because there is no bigger motivator than an 82% energy bill saving.

Before I go on, I should stress that 82% is the record energy saving that Powermaster has provided. It was achieved by combining the effects of variable speed drives, voltage optimisation, heat recovery, remote monitoring and our trademarked IWEMs (Integrated Water and Energy Management) solution in a single application.

However, energy savings of 40% are very, very common and it is far from inconceivable that we will repeat or better our 82% record in the medium term future. So why do so few companies building and installing pools and spas include energy management as part of their proposal to the building owner? This question is especially pertinent when, in the public sector, a certain degree of energy saving technology is mandatory. Furthermore, why do so few pools and spas make this very small, and often publically funded, capital expenditure commitment that will allow them to reduce their expenditure so radically?

My belief is that capital expenditure is prioritised much too highly and operating expenditure is vaguely written of as something that tomorrow’s accountants can deal with.

Let’s look at the example of a variable speed drive controlling the pump or pumps in a swimming pool or spa. The pump is driven by a motor and the entire pump and drive system will cost exponentially more to run during its lifetime than it cost to purchase. A modest addition to the purchase cost in the form of a variable speed drive, which will control the motor at either pre-set levels or in accordance with the pumps requirements, could reduce the energy bill and thus the lifetime cost of the application by a minimum of 30% in a typical swimming pool or spa application.

Perhaps the key to understanding this is recognising that the motor speed reduction and the reduction in energy use aren’t identical figures. Instead, reducing the speed of the motor by 20% will reduce the energy used by 50%. That speed reduction can be achieved by simply using variable speed drives to turn down the motors when the pool or spa isn’t being used or is being used less.

Providing variable speed drives are in place, the use of Powermaster’s IWEMs system can go on to provide even greater energy savings at relatively modest costs. At IWEM’s heart is monitoring technology that allows the variable speed drive to control the pump in accordance with the water chemistry of the pool or spa itself. This means that the motor can always run at the slowest required speed, no matter how heavily the pool or spa is being used. If variable speed drives aren’t already in place, it is perfectly achievable and entirely normal to fit them as an integral part of the IWEMs system.

Furthermore, IWEMs can be fine tuned to manage the chemical dosing of the pool or spa, which can in turn lead to further cost reductions – this time in the form of lower expenditure on the chemicals themselves.

IWEMs features a completely integrated remote monitoring system that allows the user to view the energy and chemical usage of a swimming pool or spa at the click of a button, via the Internet. So, even if you are still on the couch, you can keep up to date with the energy saving progress you are making. This function can also act as a datalogger and an alarming system, sending you an e-mail or text message if there is an urgent event that needs requires attention.

The answer to energy saving is simple, whether you are building or managing a swimming pool or spa, look at the cost of the entire facility, not just the cost of the build or the day to day capital expenditure. If you do, you will see some figures that very quickly make you get up of the couch and take action.