South African energy technology firm Plentify and property developer Balwin Properties have deployed 7,500 smart geyser controllers across 13 residential estates in an effort to reduce peak electricity demand and ease pressure on the national grid.
Electric water heaters account for up to 40% of household electricity consumption, making them one of the largest residential energy loads, according to Balwin Properties.
The devices, installed across completed developments, optimise when water is heated based on household demand patterns, solar energy availability and time-of-use tariffs, shifting consumption away from peak periods.
Data from the deployment showed a 46% reduction in peak electricity demand and a 36% decline in short-term demand spikes, the companies said. Solar energy use for water heating increased by 79%, while more than 1,400 tonnes of carbon emissions were avoided.
The system has also generated over 1 million rand in cumulative savings for residents.
South Africa continues to face electricity supply constraints, with efforts largely focused on expanding generation capacity. However, managing demand at distribution level is increasingly seen as critical to stabilising the grid.
“Ensuring power is available where and when it is needed is as important as how it is generated,” Balwin Managing Director Matthew Whalley said.
By lowering peak demand, some participating estates have qualified for load curtailment programmes run by Eskom and municipalities, reducing exposure to power cuts without the need for battery storage.
The coordinated systems effectively function as a virtual power plant, allowing households to collectively shift electricity usage.
As renewable energy capacity expands, technologies that align consumption with supply are expected to play a growing role in stabilising power systems.