READERS’ QUERIES: The Tjommie smart geyser system — Your Questions Answered

As Nelson Mandela Bay rolls out smart geyser technology, readers raised questions about what it means for households, particularly those with solar power or alternative heating systems. We asked the company behind the Tjommie device to respond to the most common concerns.

Following Daily Maverick’s report on the compulsory roll-out of Tjommie smart geyser devices in Nelson Mandela Bay, readers sent in dozens of questions about how the technology works, whether it is necessary for homes with solar power, who is allowed to install it and what data it collects.

Tjommie is a smart geyser management system that connects directly to a home’s distribution board. It monitors hot water availability, learns household usage patterns, and can remotely switch geysers on and off to shift demand away from peak periods when pressure on the national grid is highest.

We put the most common questions to Ignus du Toit, the CEO of Escoteck and Neura, the company behind the technology.

Question: In a household that operates entirely on solar power, where the geyser runs according to a schedule set in the solar system, would a Tjommie device still be required?

Answer: If a household’s solar PV system and geyser control is set up in such a way that the geyser charges only during sunshine hours, a Tjommie is not strictly necessary.

Q: I have solar panels installed, but the geyser has not been linked to this installation. However, a CBI geyser timer has been installed, and I control the geyser by scheduling the timer via an app. Will this be affected after a Tjommie installation?

A: No, it will not. A timer has a tendency to drift. Tjommie is a smart device connected to the cloud, which will optimise heating and cooling cycles. No timer is as smart as a thermostat because a timer does not know when the geyser is at an optimal temperature. A thermostat is a device that has traditionally optimised the temperature setting, so a timer that can turn the electricity to the geyser off before the optimal temperature is reached is not beneficial to the user. Tjommie only operates with the thermostat status as the reference point and, as such, is optimising the thermostat functioning.

Q: Would a household that uses a combination of solar and gas geysers still require a Tjommie device to be installed? For example, if the household switches between a solar geyser on sunny days and a gas geyser during overcast weather, would a Tjommie still be necessary?

A: If the solar geyser is still connected to electricity, then a Tjommie installation will be worthwhile.

Q: Any person who works