Trust The Sun to help you SAVE, REDUCE and INVEST with a Solar Geyser.

If you want to save money on your electricity bill, an alternative energy source for water heating is a great investment.

A geyser is one of the most energy-intensive items in a household, using roughly 30% to 40% of household electricity. Replacing the water heating system with one that uses an alternative source of energy is more efficient and will save money.

Understanding the difference between a solar geyser and a heat pump (and which is most suitable for your requirements) is a critical first step.

Solar Geysers 

A SWH uses the radiation from the sun to generate heat. The size of the solar panel will determine how much energy can be collected from the sun.

It can be connected to an electric element to further heat the water during winter and overcast days.

A high-efficiency, properly sized SWH system will typically provide up to a 50% saving on the energy required for hot water.*

Variances in the facing and incline of the solar collector panels will influence the output of the system.

Payback period is between 3-5 years. *

Life expectancy of the system is 10 years or more.

Routine maintenance may be required on the valves, but not on the system itself.

Heat Pumps

The heat pump uses a relatively small amount of electricity to extract a lot of energy from the surrounding air. A heat pump is also using the energy from the sun but only indirectly and so it can work day and night, winter and summer.

It works at night and on overcast days as it relies on air temperature and not direct sunlight.

A high efficiency heat pump produces 4 times more thermal energy as what it uses electrically – in other words a 75% saving on the water heating bill.*

The correct placement of a heat pump is essential to ensure sufficient savings. It needs to face north, east or west.

Life expectancy of the system is 10 years or more.

Payback period is between 1-3 years. *

Requires more maintenance due to the compressor and moving parts.

*Please note: As every household is different, the savings and pay-back period will vary. This will depend on the model, size and the positioning of the system as well as how much hot water the home uses.

What are the Savings & Benefits when installing a Solar Geyser Water Heater?

The following table provides some indication of what savings is typical for various households, and what repayment costs you can expect if you add the installation of a solar water heater to your existing bond facility.

The savings and payback period will vary for each household. This depends on the model, size and the positioning of the system as well as how much hot water the home uses. The general guideline is that a solar water heater can save up to 50% or more of your hot water bill.

Family Size 5 minute Showers/day Baths/day Recommended Solar Geyser size Typical Solar Geyser System Cost Typical monthly saving (avg)* Typical monthly repayment on bond (10 yrs at 10.5% interest) Typical simple payback period (yrs) if paid cash
1 1 0 150 R 19 165 R 116.60 R 265.53 8.84
1 0 1 150 R 19 165 R 159.00 R 265.53 6.68
2 2 0 150 R 19 165 R 232.51 R 265.53 4.75
2 0 2 150 R 19 165 R 288.05 R 265.53 4.00
2 1 1 150 R 19 165 R 263.40 R 265.53 4.25
3 3 0 150 R 19 165 R 306.53 R 265.53 3.75
3 2 1 200 R 21 165 R 369.87 R 293.24 3.50
3 1 2 200 R 21 165 R 394.52 R 293.24 3.34
3 0 3 200 R 21 165 R 419.17 R 293.24 3.17
4 4 0 200 R 21 165 R 413.01 R 293.24 3.17
4 3 1 200 R 21 165 R 437.66 R 293.24 3.00
4 2 2 300 R 30 450 R 501.00 R 421.88 3.67
4 1 3 300 R 30 450 R 525.65 R 421.88 3.50
4 0 4 300 R 30 450 R 550.29 R 421.88 3.42
5 5 0 300 R 30 450 R 519.48 R 421.88 3.59
5 4 1 300 R 30 450 R 544.13 R 421.88 3.42
5 3 2 300 R 30 450 R 568.78 R 421.88 3.34
5 2 3 300 R 30 450 R 593.43 R 421.88 3.17
5 1 4 300 R 30 450 R 617.15 R 421.88 3.08
5 0 5 300 R 30 450 R 637.20 R 421.88 3.00

* Based on purchasing the system with cash (no financing costs), using the City of Cape Town’s 2016/17 electricity tariff

The green row above is an indication for an average household of four people.

Please Note: These calculations come with assumptions around shower flow rate and time, and average bath capacities, and are dependent on typical heat absorption capacities of solar water heater. They should be taken as indicative, not absolute, and will vary from household to household.

Warm Water Powered by the Sun, When Installing a Solar Geyser

Convert your existing Geyser to Solar with a Retrofit System from as Little as R11 900

150L On Roof Solar Geyser System, Could Reduce Electricity Bill of R1000 to R600

Rentek gives you the best Solar Water Heating solutions, with multiple Solar Water Heating System Options

Solar Geyser Increase the value of your home and makes you more Energy Efficient

Get your Free Consultation and Quote with Rentek an accredited installer and supplier City of Cape Town Accredited Installers and Suppliers 

Become more Energy Efficient and play your part towards Climate Change.  Help us build towards a better future for your Planet

Rentek is fully behind the Western Cape Energy Game Changer initiative.  We want to play our part by making simplest most affordable way to converting to Solar Water Heater

Contact us:

Head Office Address:

58 Loch Road
Cape Town

Phone Number:021 829 0786

About us

Working in solar heating industry for 20 years, we have established ourselves as a reputable and trusted energy solution provider. Our consultancy is the fastest growing solar water-heating consultancy in Africa. The mechanism, as depicted by its name, is based on use of sunlight energy to heat up water and reduce electricity costs in an environment friendly way.


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