Advice and Opinion

What to know when choosing an alternative water heating system

Solar panels generic

With the latest tariff hikes placing more pressure on consumers it is becoming increasingly important to find alternatives for the largest energy consuming appliances in the home. This is according to Cala van der Westhuizen, Head of Marketing and Sales at Energy Partners Home Solutions, a division of Energy Partners and part of the PSG group of companies, who says that water heating accounts for as much as 50% of a household’s electricity use.

“Replacing a home’s conventional geyser with a renewable energy alternative is one of the first steps to drastically reduce an average home’s monthly electricity spend. The current renewable energy powered water heating options available to home owners are heat pumps and solar water heaters.”

He explains that a heat pump uses energy from the surrounding air to heat water, while a solar water heater relies on the sun for power. “Both of these options are a good energy-smart investment, but each holds different advantages and disadvantages,” he says.

Van der Westhuizen notes that understanding the major differences between the two systems will help home owners to choose the system that is right for them.

“A solar water heater is much easier to install than a heat pump, and the total cost of an average 200ℓ system is around R 26 000. In the short-term, this is cheaper than an average heat pump with a 300ℓ efficient tank system, which costs around R 35 500,” he explains.

Solar water heating systems can also be expected to last for over ten years, while heat pumps generally need to be replaced after five to ten years.

Van der Westhuizen says that despite initial upfront costs, heat pump systems have significant advantages over solar heating. “A solar panel needs to be oriented towards the sun to operate at maximum efficiency, and when there is no direct sunlight on the system, like at night or on an overcast day, the system relies on a regular geyser element. As a result, the efficiency of a solar heating system fluctuates between 45% and 70%. This comes down to an average drop in energy costs by approximately 54% over the course of one year.”

In contrast, a heat pump system is only slightly affected by variations in temperature, and therefore it runs efficiently at any time of day, says Van der Westhuizen. “It requires approximately one-third of the energy of a conventional geyser to heat the same amount of water, resulting in an average energy saving of up to 70%. This results in a cumulative cost saving of around R 62 500 for a standard four member household using an average of 52ℓ of warm water per person over a ten year period. By comparison, a solar heating system achieves around R 59 500 in savings under the same conditions,” he adds.

Van der Westhuizen says that Energy Partners Home Solutions recommends installing heat pumps to the majority of their clients in the Western Cape and Gauteng. “It is more efficient than an electric geyser and leads to bigger electricity savings over the long term than a solar water heater. These regions also receive less sunlight during their respective rain seasons, which means that a solar geyser will use a lot more electricity from the national grid,” he says.

“Heat pumps are consistent, rely on air and, can cut the cost of water heating by more than any other system currently on the market,” Van der Westhuizen concludes.