This may come as a shock to you, but before you spend more than a R1000 to install a Geyser Timer, have a look at these tests…
At best one can say the only energy-saving one can expect from switching off the geyser for an extended period each day is a reduction in the average number of re-heating spikes per day (reduced from 5 to 3.5 in this test). Which is thus a maximum saving of 0.42kWh per day. For a saving to occur, no additional energy should be used when the geyser is switched on again, other than that required to heat the cold water that replaced hot water used in any shower whilst the geyser was off. However in this test no such saving was observed, the reverse in fact.
Geyser Test - Time Switch Simulation
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