We decided to conduct a quick test to see how efficient an induction hob was in comparison to a conventional electric stove/hob.
The test was very simple. We measured out and boiled exactly one litre of water, using the same pot on each type of stove. We measured the power consumption of each, as well as the time taken for the water to boil. We then multiplied the average power consumption by the time taken to boil, to get the energy consumed and then compared the values to determine the efficiency (or not) of the induction hob.
In both cases the water was taken directly from the cold water tap, within a few minutes of each other, and the pot, water and stove started at the same normal room temperature each time.
Conventional Electric Stove
In the meanwhile a clamp meter, that could measure power, was attached onto the stove wire in the DB board, to monitor the power consumed . The initial power reading was 1.43kW.
As the water got close to boiling we re-checked the power and noticed that the reading had dropped down to a lower value of 1.358kW.
So using the average of the two power readings, which is 1.394kW, we get an energy consumption of 0.1717kWh, for the conventional stove to boil one litre of water (by multiplying the average power consumption by the time).
The pot was cooled down by emptying it, and then allowing cold tap water to flow over it until it was completely cold to the touch. It was then dried and allowed to stand for a few minutes, to ensure that it was definitely back to room temperature.
We then measured out exactly 1 litre of cold tap water, poured that into the pot and put that onto the induction hob. The hob was switched on and the stop watch was simultaneously started. The hob was dialed rapidly up to full power.
Its always amazing to see the bubbles form in the water almost immediately!
In the meanwhile we had reattached our power meter to a cable supplying power to the hob. The initial reading was 1.419kW.
We waited for the water to boil and took another power reading when we could see the water was close to boiling, as before.
The second reading wasn’t that different in this case.
When the surface of the water just started to become violently agitated (we actually waited a second or two to be sure), we stopped the stop watch.
The average of the two power readings was 1.423kW, which yields an energy consumption by the induction hob of 0.1157kWh to boil one litre of water.
So according to this test, the conventional stove used 0.1717kWh to boil one litre of water while the induction hob used 0.1157kWh to boil the same amount of water in the same pot. That represents a saving in energy of 33%!