With power prices these days, energy efficiency can be a key factor to purchasing a new cooktop. So which ones are more efficient? Are there any other factors at stake to consider?
Leave your answer in the comments below and you will enter our competition.
I will say INDUCTION, and we have one!
Induction saves all that energy being lost to heating and electrical element, or creating a flame which is needed to heat the cooking utensil.
Induction uses the electric power to induce an electrical current in the cooking utensil which in turn heats the contents. Much more efficient.
Just as a mention and this does not influence it’s efficiency…Induction does require the use of ferromagnetic metal cookware (eg cookware that has or is stainless steel, cast iron) or the use of a similar metal plate to put glass, copper etc on.
It looks like an obvious question but…
Define efficiency. The lowest cost to operate; on which plan? That which is the best environmental outcome? Would that include with and / or without solar panels for electric and whether or not the panels could power it.
If one has an off-grid fully self sustaining solar system it could be a different answer to a CBD resident with an induction cooker. Does a ‘free’ induction system provide more practical efficiency than a free conventional electric cooktop or does it become academic as a consumer? (Pardon the contrived example but I think it makes the point on ‘what is efficiency?’)
It really depends on what you are doing. For boiling water a simple immersion element is the most efficient, and gas the least efficient, with induction, resistive hotplate and microwave, in that order, in between.
Summary of some testing I did a few years ago:
Boiling water for a cuppa - which is the most efficient way?
Ever wondered which is the most energy efficient way to boil a cup of hot water?
I’ve done a comparison using several methods:
Induction cooktop with kettle +375ml water
Gas burner with same kettle +375ml water
Ceramic electric jug + 375ml water
Microwave oven with 375ml water in a large mug
Immersion heater in same large mug with 375ml water
Water temp was 12C
I don’t have any sort of electric hotplate, so that is not included in the comparison, however, it is considered to be less efficient than induction heating.
Results:
Immersion heater …118sec_____ 48.3Wh … @1473W
Electric jug …115sec_____ 51.6Wh …@ 1615W
Induction cooktop …101sec_____ 63Wh … @2246W
Microwave oven …171sec_____ 89.5Wh … @1884W
Gas burner …167sec_____ ~270Wh … @~5700W
EDIT: BTW, all tests done with off-grid solar power
The other one is time efficiency…which one heats and cooks the quickest.
I was hoping these questions would be drawn out @PhilT. When people think of efficiency, I believe this is most commonly equated to ideas of ‘lowest cost’, ‘lowest energy use’ and ‘lowest environmental impact’. The word in relation to purchasing cook tops draws its meaning on this combination, but that’s not always so simple.
As @gordon points out, it also depends on what you’re doing. By the way, thanks for the ‘boiling hot water’ test results, that illustrates the point very nicely. So, this ‘simple’ question needs a multi-pronged answer that accounts for solar connected households, suburban households, environmental impact and maybe even time for a large household/cooking quality are factors at a certain point. I know some home chefs have strong feelings the quality of different cook top methods, so this could be a sub-factor in a way.
With all those considerations, I think we can possibly avoid extremes though - a 20 person household that specialises in boiling homemade spaghetti and searing toast may exist, but for the purposes of this question we can probably focus on a more typical type of scenario/s.
Not a quantitative comparative test as such, but I often cook a lot of home grown fruit for preserving - mainly cherries and apricots in late spring/early summer. Gas makes the kitchen unbearably hot due to its inefficiency (all that hot air rising around the outside of the pot), and fortunately I haven’t had to use it for a number of years, thankfully the hugely more efficient induction hob keeps the kitchen temperature much lower.
