Local Partnership Puts Demand-Side Management to Work in South Africa
Sensor Networks, a South African leader in smart-home energy technologies, has partnered with European demand-side management specialist ThermoVault to bring advanced load-shifting capabilities to one of the country’s biggest energy consumers: the household geyser.
Every year, more than 500,000 geysers are installed across South Africa, in new developments and as replacements in existing homes. Geysers are typically the single largest source of electricity usage in a household, operating independently of whether hot water is needed. This represents a massive, largely untapped opportunity for the national grid: thousands of distributed loads that, if coordinated, could be intelligently managed to reduce demand during peak periods.
Sensor Networks and ThermoVault are working together to enable real-time, remote control of smart geysers, allowing utilities and licensed load aggregators to shift geyser loads in response to grid needs ; without disrupting comfort or hot water availability in the home.
By delivering the technology backbone for smart geyser control, Sensor Networks enables utilities and aggregators to respond rapidly and efficiently to grid demands. The collaboration combines Sensor Networks’ smart geyser technology expertise with ThermoVault’s AI-based optimisation engine, already proven in several European markets.
Geysers are ideal for load-shifting, as they store thermal energy, allowing water to be heated earlier or later without affecting the user’s experience. This flexibility enables the system to optimise heating times, ease pressure on the grid, and improve energy efficiency —all automatically, with no action needed from the user.
In Europe, demand-side aggregation of thermostatically controlled loads, including geysers, heat pumps, and HVAC systems, is already a well-established method for balancing the grid. These loads act as virtual power plants, capable of shifting megawatts of demand in real time, especially useful as renewable energy introduces more variability into the supply mix.
By bringing that same model to South Africa’s extensive base of residential geysers, Sensor Networks is helping to unlock demand response at scale, in close coordination with existing utilities and aggregators.
“Geysers are a perfect fit,” said Thibaut Gérard, Head of Demand Response at ThermoVault. “They consume a lot of power, but their flexibility means they can be intelligently shifted, and when you aggregate enough of them, you create meaningful stability for the grid.”
And with the recently announced strategic partnership between Sensor Networks and global water heating leader Ariston, the potential to scale this solution is significant. By embedding this capability into Ariston’s footprint of new installations, the platform can rapidly expand, helping to stabilise the grid while delivering value to households.
This marks a major step in modernising South Africa’s energy system; not just by building more capacity, but by making smarter use of what we already have. Through innovative partnerships and technology, homes across the country are becoming part of the grid solution, one geyser at a time.