Yes. If you have a standard electric geyser and a roof that gets sun, you can convert it to solar without replacing the tank. Solar panels go on the roof, a cable runs down to the geyser, and the geyser's thermostat is swapped for one that can take power straight from the panels. Your tank, your plumbing and your hot taps stay exactly as they are.

You don't need a new tank on the roof. A solar geyser conversion keeps the geyser you have, which makes it a much smaller job than replacing it.

What changes when you convert a geyser to solar

Three things are added:

• Solar panels on your roof. They make electricity from sunlight.

• A cable from the panels to your geyser. It carries that electricity to the element inside the tank, the same element that heats your water today.

• A new thermostat unit on the geyser. This is the part that makes the conversion work. Fitting it typically takes under 15 minutes, and it runs a self-test before the installer hands over.

There's no inverter and no battery. The panels heat the water directly, and your insulated tank stores that heat until you need it.

In the trade this is called a retrofit: an upgrade to the geyser you already own.

What stays the same

Your geyser keeps its connection to the grid. The element is the same one the grid has always heated, so on a run of cloudy days the grid can still do the job.

How much say you have over that depends on the unit. Elon 100 has a single dial: sun only at one end, grid only at the other, and a mix in between. Elon Smart, the connected version, uses Top-Up Rules in an app so you decide when the grid is allowed to heat the water, and it shows your savings in rands.

Is your geyser suitable for a solar conversion?

Four things decide it:

• The geyser. Elon is designed for Kwikot geysers, the most common brand in South Africa. Your installer will confirm yours is compatible.

• Its condition. A conversion upgrades a healthy tank. If yours is old, leaking or already failing, the first decision is whether to replace it.

• Your roof. It needs to get sun. Heavy shade rules it out.

• Roof rights. In some complexes, residents don't have the right to use the roof. Check before you plan panels.

Who does the work

A solar conversion is electrical work on your roof and your geyser, so it has to be signed off by an electrician, who issues a supplementary Certificate of Compliance: the signed document confirming the new wiring meets the rules. Keep it: without one, your insurer or the geyser's manufacturer can refuse to cover a later problem.

Use an installer trained on the system. We train and certify installers through our own programme.

What it does in a real home

A family of five in Ballito gets 85% of their hot water from the sun, saving R1,040 per month. You can see all four monitored homes here.

What a solar geyser conversion costs

If you're searching for a conversion kit, there are two ways to buy one:

• The installed conversion: panels, the Elon unit and installation, done in one go.

• The Elon Smart unit first: fit it now and have an installer add panels as a second step.

Each route has a different price and a different place to buy it. For the installed conversion, ask for a quote for your home.