Heat Pump Geysers in South Africa: Cost, Savings and Payback

How a heat pump geyser works

A heat pump has a fan, an evaporator, a compressor and a heat exchanger. The fan draws outside air over the evaporator, where a refrigerant absorbs its warmth. The compressor squeezes the refrigerant, raising its temperature, and that heat passes into your water. The cooled air blows out the other side.

Because the heat pump moves heat rather than creating it, it delivers more heat energy than it consumes in electricity. The US Department of Energy describes heat pump water heaters as two to three times more efficient than conventional electric-resistance water heaters.

Our overview of the five types of geyser places the heat pump alongside electric, gas, solar and hybrid options. This page goes further into heat pump cost, savings and payback.

COP explained, with real South African numbers

COP stands for coefficient of performance. It is the heat delivered to the water divided by the electricity used:

• An electric element has a COP of about 1. One kWh of electricity gives about one kWh of heat.
• A heat pump with a COP of 3 gives three kWh of heat for every kWh of electricity, so it uses a third of the electricity for the same hot water.

COP isn't fixed. It falls when the air is cold, and it falls as the water gets hotter, because the heat pump has to work harder in both cases. So the number on a brochure, measured at a favourable test condition, is usually higher than what you'll average over a year.

The most useful local evidence is a University of Fort Hare study, published in the Journal of Energy in Southern Africa in 2018, which monitored a split heat pump and an integrated heat pump, each on a 150L tank, through summer and winter:

The range within each row reflects how much hot water was drawn off (50 to 150 litres). The integrated unit in the study had an electric backup element, which pulled its COP down. Newer products may do better, but these are measured South African figures, so we use COP 2.1 to 3.0 in the calculations below.

How much does a heat pump save? A worked example

Here are the assumptions, so you can change any of them:

• Household: two adults using 80 litres of hot water each a day (the per-adult figure Eskom uses), heated from 20°C to 60°C. That needs about 7.4kWh of heat a day.
• Tank: a 150L Class B geyser, which may lose up to 1.40kWh a day in standing losses under SANS 151, according to Kwikot's geyser guide. The heat pump has to make up those losses too.
• Tariff: Eskom's Homelight 60A rate for 2026/27, 343.61c/kWh including VAT. Municipal customers should use the energy charge from their own bill or tariff schedule.
• Month: 30.4 days.

Electric elementR924

440R2.1

369R2.5

308R3.0

These are SolarGuide calculations, not measured bills. Your saving scales with how much hot water you use: a family of four using twice as much hot water saves roughly twice as much in rands, while a single person saves less. A higher tariff saves more, and a lower one less. For your own baseline, our geyser cost calculator works out what your electric geyser uses now from your household size, tank and tariff.

What does a heat pump geyser cost?

We haven't published a price range on this page because we couldn't verify a current, like-for-like installed price from a primary source. Installed prices vary with the unit's size, whether it's a retrofit or an integrated tank, the plumbing distance, the electrical connection and where you live. Ask for a written, itemised quote that shows:

1. The unit: make, model, heating capacity in kW, rated input in watts and the tank sizes it's designed for.
2. Retrofit or integrated: whether your existing geyser stays, and if so, whether it has been checked and is in good condition.
3. Plumbing and electrical work, including a dedicated isolator and protection for the unit.
4. Controls: the timer or thermostat settings, and whether the old element is disconnected, kept as backup or put on a timer.
5. Compliance: Kwikot notes that geyser installations must comply with SANS 10254 and be done by a registered plumber who issues a Certificate of Compliance. Electrical work needs a registered electrician.
6. Warranty: separate terms for the compressor, the heat pump unit, the tank and the workmanship, and who handles a claim.

Then use the payback method below to judge the quote, rather than comparing headline prices alone.

Working out your payback

Payback is the time it takes for the savings to cover what you paid:

Payback in years = installed quote ÷ annual saving

Using the mid-case saving of R6,651 a year from our example, every R10,000 of installed cost takes about 1.5 years to earn back. In the cold-weather case (R5,806 a year) it's about 1.7 years per R10,000; in the good case (R7,390 a year) about 1.4 years.

A quote three times that size would pay back in about 4.5 years at the mid case. Plug in your real quote and your real saving and the answer is yours, not a brochure's.

Two things change the picture a lot:

• If your geyser has burst or is near the end of its life, compare the heat pump with the cost of a new electric geyser, not with nothing. Only the extra cost needs to be paid back, and that shortens payback considerably.
• Tariffs rise most years. Eskom's direct tariffs went up by 8.76% from 1 April 2026. If increases continue, each year's saving grows and payback comes sooner than the simple sum suggests.

What this method leaves out: servicing costs, a compressor repair outside warranty, and the time value of money. If you're financing the unit, add the interest.

Retrofit or integrated?

The US Department of Energy notes that a heat pump water heater can be bought as an integrated unit, with a built-in tank and backup elements, or retrofitted to work with an existing conventional storage water heater. In South Africa:

• A retrofit (split) heat pump sits outside next to the house and circulates water to and from your existing geyser. It's often the cheaper route if your geyser is sound, and it leaves the tank where it is. The Kwikot Kwikpump HP-003, for example, is listed as compatible with existing electric or solar geysers and recommended for 100 to 150 litre tanks.
• An integrated heat pump replaces your geyser with a single tank that has the heat pump on top or alongside. It's a neater choice when the old geyser needs replacing anyway, but it has to stand somewhere with enough air around it, which a ceiling void usually isn't.

In the Fort Hare study, the split system achieved higher COPs than the integrated unit in both seasons. That reflects those two particular products, so check the performance figures for the specific models you're quoted.

Sizing a heat pump

Size the heat pump to the tank and to how quickly you need hot water back:

• Match the tank. Manufacturers specify which tank sizes each unit suits. A unit made for 100 to 150 litres will struggle to reheat a 200L tank in reasonable time.
• Check the recovery rate. This is the hot water the unit can produce per hour. The Kwikpump HP-003's listed output is 54.4 litres an hour, for example, so a full 150L tank takes a few hours to recover. A heat pump reheats more slowly than a 3kW element, which matters for big households with back-to-back showers.
• Think about your pattern. If everyone showers in the morning, the tank has to be hot by then. Running the heat pump in the afternoon (when the air is warmest and COP is best) and keeping the tank well insulated usually works well.

If you're building a new home, it's worth knowing that SANS 10400-XA requires at least 50% of the annual hot-water demand to come from something other than electrical-resistance heating, as Kwikot's guide summarises. A heat pump is one of the usual ways to comply.

Noise and placement

A heat pump has a fan and a compressor, so it makes a sound like an air-conditioner's outdoor unit. Kwikot lists the Kwikpump HP-003 at under 52dB(A). Practical placement points:

• Airflow. It needs clear space around it to draw air in and blow cool air out. Don't box it into a cupboard or tuck it behind a wall where it re-breathes its own cold air.
• Neighbours and bedrooms. Keep it away from bedroom windows, yours and the neighbours'. Some estates have rules on where outdoor units may go.
• Cold air. The exhaust air is noticeably cooler, which is welcome in a garage in summer and less so beside a patio in winter.
• Climate. Check the operating range. The HP-003 is listed at −7°C to 43°C ambient. Coastal homes should ask for a model rated for corrosive salt air; Kwikot, for example, sells separate inland and coastal versions.
• Drainage. Heat pumps produce condensation, so the installer needs somewhere to drain it.

Heat pump vs solar geyser vs solar PV heating the water

Three good options all cut water-heating costs. They suit different homes.

• Choose a heat pump if your roof is shaded or awkward, you want the lowest running cost from a single appliance, and your existing geyser can stay. Our solar geyser price guide explains how to compare solar water heating quotes if you're weighing both.
• Choose a solar geyser if you have a good north-facing roof and want the sun to do most of the work directly.
• Choose solar PV if you want to cut the whole electricity bill, not just the water heating. A PV system can run a timed element or, better, a heat pump in the middle of the day on your own generation. The heat pump uses far less of that solar power, leaving more for the rest of the house. Our solar geyser vs solar PV comparison explains when to start with which.

Many homes end up combining them. A heat pump running on solar power in the afternoon is one of the most efficient ways to heat water in a sunny country.

If you're planning solar panels, tell the installer how you heat water so the system is sized for it, and ask whether the heat pump or geyser can be scheduled to run on solar. Size a solar system around your water heating →

What about gas?

A gas geyser is the other common alternative. It costs more to run than a heat pump: in our gas geyser guide, the same two-adult household pays about R720 to R790 a month for LPG at October 2026 prices. Gas wins on grid independence, because battery-ignition models keep working through outages.

Frequently asked questions

How much electricity does a heat pump geyser save?

It depends on its COP and how much hot water you use. South African field tests measured COPs of about 2.1 to 3.2, which means a heat pump uses roughly a third to a half of an element's electricity for the same hot water. For two adults on Eskom's Homelight 60A rate, that works out to about R480 to R620 a month in our worked example.

Is a heat pump better than a solar geyser?

Neither is better everywhere. A heat pump works at night and needs no roof space, but it uses some electricity and makes some noise. A solar geyser uses the sun's heat directly but needs a good unshaded roof and relies on its backup element in poor weather. Shaded roofs and homes keeping their existing tank tend to favour a heat pump.

Can I connect a heat pump to my existing geyser?

Usually, yes, if the geyser is in good condition and the right size for the unit. Retrofit heat pumps are designed to circulate water through an existing electric or solar geyser. Have the tank checked first, because fitting a new heat pump to a geyser that's about to fail is a false saving.

Does a heat pump work during load-shedding?

Not on its own, because it needs electricity to run. The hot water already in the tank stays usable for hours. A heat pump can run during an outage only if it's on a circuit supplied by an inverter and battery sized for it, which a heat pump makes far easier than an element because it draws much less power.

Is SolarGuide the installer?

No. SolarGuide is an independent referral partner for solar PV systems, which Alumo supplies, installs, finances and warrants. We don't sell or install heat pumps, so get the heat pump itself quoted by a qualified supplier. We can help you compare solar options and get a free quote. All pricing is indicative and subject to a site assessment and credit approval.

Sources and review note

Checked on 20 October 2026. Measured COPs come from Tangwe, Simon and Mhundwa, "The performance of split and integrated types air-source heat pump water heaters in South Africa", Journal of Energy in Southern Africa 29(2), May 2018, Tables 6 and 7. The efficiency comparison and the retrofit and integrated definitions are from the US Department of Energy. The electricity rate is Eskom's Homelight 60A energy charge from the 2026/27 Schedule of Standard Prices, Table 14, and the 8.76% increase is from the same schedule. Standing-loss limits, SANS 10254 and SANS 10400-XA are as summarised in Kwikot's electric geyser guide. The Kwikpump HP-003 output, noise, operating range, tank sizes and retrofit compatibility come from Kwikot's product page; these are manufacturer specifications and we name the product only as an example, with no commercial relationship. Monthly costs, savings and payback per R10,000 are SolarGuide calculations from the stated assumptions. We did not publish installed prices because we could not verify a current like-for-like figure from a primary source.