But a new problem has reared its head, leading local municipalities to implement planned outages during peak times that are not dissimilar to load shedding schedules.
This so-called "load reduction" is a grid constraint problem, where local infrastructure - such as cabling and transformers - can't handle the load on the system. Since geysers are a major contributor to peak demand loads, more efficient heat pumps present an alternative that can reduce loads while ensuring households have hot water.
"Grids are failing because of all the geysers coming on at the same or similar times," said Metrowatt CEO David Neale in an interview. "Load spikes are typically in the morning and early evening when hot water is needed for showers and other household uses. A typical geyser draws around 3kW of energy, and heat pumps only need about a quarter of that."
"If everybody had heat pumps you would reduce spike loads and protect the grid," Neale said.
In a geyser, an element is heated and the heat is then transferred to the surrounding water. A heat pump, on the other hand, works in the same way as a refrigerator or air conditioner by moving heat from one place to another.
