I think what you and kaleo are debating is the difference of total energy efficiency vs local energy efficiency. At your home, in your kitchen, an induction cooktop is definitely more efficient than any other heating methods (gas, electric coil…). I remember induction is about 80-90% efficient. Gas stove is maybe on average 40%? Something like that.
However, in order to generate the electricity for the induction cooktop, the local power plants are probably burning coal and gas. From what I found, natural gas power plants are about 40-60% efficient. So, let’s say 50%. On average there is about 5% energy loss from the power plants to your house. Long story short, the question has a lot of variables. The “three times more efficient” than gas is the very ideal situation and only looking at your cooktop. It does not account how the electricity is being produced. All in all, there maybe some energy saving, but certainly not by 2-3 folds.
