Your geyser is probably the most energy-consuming appliance you might own. On average, it represents between 25% and 40% of the total amount of your electricity bill. So we help you figure out how to reduce its energy consumption and your electricity bill at the same time.
Use an electric geyser
According to a study conducted by Stiebel-eltron, if you compare the consumption between a gas and an electric geyser, the electric geyser actually consumes less energy, and is therefore cheaper! The experiment was conducted in the same conditions for both the gas and the electric geyser.
Below are the energy costs to heat 200 liters of water per day for one month:
|Electric geyser running 24 hours a day. (No timer!)||Gas geyser with electric pilot flame starter|
Conclusion: an electric geyser can help you save at least 6% energy compared to a gas geyser.
Switch off your geyser won’t help
A very common but misconceived idea consists of thinking that switching off a geyser will decrease the energy consumption. Well, if the switch-off period lasts at least a few days, then sure, but if it is only for the day then don’t.
A geyser is like a barrel filled with cold water. To heat the water to the temperature setpoint, the geyser has a resistance. When no one is using hot water, the temperature of the water should remain the same as no cold water is being let in. However, depending on the quality of your geyser and of its insulation, heat will “leak” from the geyser into the surrounding area.
So in one hand, if you leave your geyser permanently switched on, the temperature will be hot all the time, so the energy needed to warm the water (because of heat leak) is constant and not extremely important. On the other hand, if you switch off your geyser, no energy will be consumed to warm the water any longer, but when you switch it on again, the resistance will need a huge amount of energy really fast to warm the water back up to the set temperature.
Most of the time, the huge amount of energy needed to make the resistance function again is higher than the energy consumed if you let your geyser switched on but at a low temperature and with a good isolation.
Install a geyser blanket
A geyser loses on average 1°C per hour (note that it depends on insolation and geyser type), so constant energy is needed to maintain the temperature. However a geyser blanket can cut this energy consumed by half, while making your water system even more efficient!
Most modern heaters already have a good insulation as they comply with the SANS 10400-XA regulation and with other international norms when they are imported. Insulating your geyser and pipes on this type of geyser will allow you to save at least 300 kWh/year depending on the current efficiency of your system (a standard geyser loses about 400 to 500 kWh/year in heat loss and you can expect to drop this number to 90 kWh/year with a good insulation. Source: Saskatchewan Research Council). If the geyser is old, the saving can be more important. This represents a saving of about R200 per year if we only take into account the efficiency of your water system. The geyser blanket prices are about R150, so you do not even need a year to pay back your installation!
What is the ideal geyser temperature?
The temperature of your geyser should be between 55°C and 65°C. However if you want to save money, we would advise you to set it up at 55°C on average, since a lower temperature means less consumption. According to Eskom, switching the geyser’s thermostat temperature from 70°C to 60°C help you achieve a small saving of 18kWh (= 5%).