Everyone knows that the geyser is the biggest energy-glutton in the house, gobbling up 30% to 50% of the monthly electricity usage all by itself.

 

But not everyone is convinced that the best alternative is necessarily a solar geyser, says Berry Everitt, CEO of the Chas Everitt International property group.

“Another option is a heat pump, which can deliver the same heat output as an electrical element for about one-third of the electricity consumption.”

“Heat pumps utilise free energy by extracting heat from the atmosphere and transferring it efficiently to the water in the geyser. They use only a little electricity to power the process and they are designed to operate even in winter and even when it rains.”

He notes that a regular heat pump will heat 200 litres of cold water to 60ºC in about an hour even if the air temperature is only around 5ºC.

“Heat pumps are also easy to install. They are compact and do not rely on direct sunlight for performance, so can be mounted low to the ground and out of sight at the rear of the home.

“What is more, heat pumps can also be used instead of energy-guzzling air conditioners to heat and cool your home very efficiently, and to heat swimming pools and spas.”

And because their main energy source is natural and renewable, Everitt notes, they are also a great way for homeowners to reduce their carbon footprint as well as their electricity bills.

Readers' Comments Have a comment about this article? Email us now.

I just sued a company to take off their solar geysers due to high electrical costs, installed a heat exchange pump and I now have the two things I set out to achieve, hot water all the time and cheaper electricity! – Anonymous

Has anybody done a proper evaluation of the benefits of using a heat pump compared to solar water heating? As a home owner I would like to make use of these technologies but I am not sold on the solar water heating sales pitch that tells me I can save up to 60% of my electricity bill.

If I look at what the sales pitch says then think about it logically it might be possible to save me 50 to 60% of my water heating bill but that means that an efficient system even with the Eskom rebate will take 10 or 15 years to break even! You can do that by ensuring efficient use of your geyser by installing a time switch and insulation on the geyser and piping! – Dave Taylor

Heat pumps are great for general heating of homes as well, BUT here in New Zealand people have found that when the heat is mostly needed, at the coldest of night, the heat pumps do not work as the ambient outside temperature dropped too low. If this would be the case in the geyser set-up, you would end up with cold water on the coldest Highveld days. - Cary Cairncross

Everitt does not say how much power a "heat pump" consumes to heat 200 litres to 60 degrees. I would like to know. And air conditioners are "heat pumps", exactly as he describes. My air conditioner is mostly used to heat the room. It compresses gas to generate heat inside the room, then expands the gas outside the room which cools it, and the air heats it again. This is a pumping action. - Fanie van der Walt

The article is not correct.

You state a heat pump is more efficient than “energy guzzling air conditioners”. A heatpump is basically an air-conditioning unit. Heat pumps have COP’s of around 3-3.1 whereas most AC’s have COP’s from 3-3.4. You should state that the heat pump is as effective as an AC.

You state the main energy source is renewable! The only energy source for the heat pump is electricity, which is made from fossil fuel in SA. The heat pump moves heat around from outdoors to indoor, but the energy source that drives the pump remains electricity. – Rory

Barry Everitt is 100% correct about the energy efficiency of the heat pumps. The energy efficiency of these units is around 3.0 - 4.3 and it's verified by third party laboratories. This means that for every 1kw/h of electicity input, it provides 3.0 - 4.3 kw/h of water heating.

Metraclark now has the i_Geyser, which is a stand alone heat pump water heating unit. This unit can be installed outside and inside but users prefer to install them in laundries, garages, kitchens etc, where efficiency can be maximised.

It uses any free heat generated inside the home and delivers up to 9000btu of FREE cooling and dehumidification.

The beauty of this unit is that it's aesthetics allows it to be installed in kitchens where the user can interact with it through selection of 3 different modes, desired water temperature and even a timer. Free cooling can be ducted into the ceiling and back into rooms that could benefit from the free cooling. Available modes are economy, hybrid and electric heating.

Heat pumps do not suffer from cracking pipes in severely cold conditions or crack seals in direct sunlight, do not put pressure on roof structures and users don't have to climb onto roofs to clean bird droppings and dust. Plumbing and electrical connections are standard. – Philip Theunissen

Some of the comments above are not correct.
Yes! the heat pump is very similar to an air-conditioning unit and uses about the same amount of electricity.
The difference is that an air-conditioner is not compared to anything, where a heat pump is compared to your electrical element in your current geyser, that is where the saving is made.
With the electrical element for every 1KW of electricity used, you get 1KW of heating.
With the heat pump for every 1KW of electricity used you get 3-5KW of heating depending on the ambient temperature.
Now remember it is ambient temperature not UV rays or direct sunlight, so it does work at night, rainy weather, winter, 24/7.
@ an average ambient temperature of 20 degrees you have a COP (coefficient of performance) of 3.8, depending on the make.
That means it is 3.8 times more efficient than a standard High/low pressure geyser.
If you have any queries or would like more information on heat pumps please call me on 0833366866 - Deon v d Merwe