What to consider when choosing an alternative water heating system

With the latest utilities tariff hikes placing more pressure on consumers it is becoming increasingly important to find alternatives for the largest energy consuming appliances in the home, says 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.

“Water heating accounts for as much as 50% of a household’s electricity use. Replacing a 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 homeowners are heat pumps and solar water heaters,” says van der Westhuizen.

“A heat pump uses energy from the surrounding air to heat water, whereas a solar water heater relies on the sun for power. Both options are good energy-smart investments, but each has different advantages and disadvantages.”

Van der Westhuizen notes that understanding the major differences between the two systems will help homeowners 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 200 litre system is around R26 000. In the short-term, this is cheaper than an average heat pump with a 300 litre efficient tank system, which costs around R35 500,” he says.

Solar water heating systems can also be expected to last for over 10 years, while heat pumps generally need to be replaced after five to 10 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 about 54% over the course of one year.”

In contrast, a heat pump system is only slightly affected by variations in temperature, so it runs efficiently at any time of day.

“It requires about 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 R62 500 for a standard four member household using an average of 52 litres of warm water a person over a ten year period. By comparison, a solar heating system achieves around R59 500 in savings under the same conditions,” he says.

Van der Westhuizen says that Energy Partners Home Solutions recommends installing heat pumps to most 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.