Microwave versus stovetop: which will save you more money?

Could you be saving money by using your microwave more often?

Most Australians have a love – hate relationship with their microwave: they’re happy to use it for reheating but not so much for cooking. So we find out whether you could be saving money if you used it more often.

Before we get started, though, let’s discuss a few things. Firstly, we’ll address the radiation issue. Microwaves are called microwaves because they emit electromagnetic radiation called microwaves to cook your food. Microwave radiation is not cancer-causing, it just causes food molecules to move faster, and it’s this motion that heats your food.

Secondly, microwaving will not adversely affect the nutrients in your food any more than heating it on the stove or in the oven. When boiling vegetables, in particular, nutrients leach into the water in which they’re cooked, so, because you use less water when heating in a microwave, you may even preserve more of the food’s nutritional value.

Now, let’s get down the the nitty gritty: microwave versus stovetop – which one will save you money?

Well, as best I can work out, cooking a pot of carrots on a stovetop will take around five minutes for the water to boil, then a further five to eight minutes to cook the carrots. Whereas, it only takes about five minutes to cook carrots in a microwave. Based on these minimum estimates, here’s a breakdown of the cooking costs:

 Appliance

 Type

 Cost per kilowatt hour

 Cooking cost

 Conventional microwave

 1300W

 34 cents

 1.7 cents

 Convection microwave

 1600W

 42 cents

 2.6 cents

 Electric hotplate

 1000W

 26 cents

 5.2 cents

 Electric hotplate

 2000W

 52 cents

 10.4 cents

 Gas cooktop

 28mJ

 56 cents

 11.2 cents

The national average cost of electricity per kilowatt hour is 26.38 cents per kilowatt hour (c/kWh). Costs taken from estimates by the Australian Energy Market Commission
Estimated appliance costs taken from
www.essentialenergy.com.au
Gas costs based on estimates taken from
www.essentialenergy.com.au

Surprisingly, cooking a pot of carrots on a gas stovetop was the least energy efficient of the bunch, with the microwave being at least twice as efficient as electric cooktops. It is worth mentioning that we have not assessed induction stovetops, which are twice as efficient as gas and electric stovetops. But if we were to make an estimate based on the above calculations, an induction cooker would still be less efficient than using a microwave.

So, it seems the microwave is the least expensive option, but there are still tips you can follow to save even more money.

Stovetop

  • Use clean, flat-bottomed saucepans to ensure the best heat transfer possible.
  • Always use the right-sized hotplate. If your pot covers the hotplate, you are ensured better heat transfer.
  • It’s actually more energy efficient to cook on low heat for longer rather than high heat in short bursts.

Microwave

  • Turn off your microwave at the wall because the clock on your microwave consumes more power than cooking does.
  • Defrost frozen food in the fridge rather than your microwave.
  • Using your microwave for cooking and reheating uses less energy than doing so in your standard oven (it may not taste as good though!).
  • A clean microwave will operate more efficiently than a dirty one.

Do you have any power-saving cooking tips for our members? Why not share them?

Read more at www.sustainability.vic.gov.au

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    COMMENTS

    To make a comment, please register or login
    Lorrainehk
    20th May 2016
    10:38am
    Microwaves do not move the food molecules to produce heat but move the water molecules in the food, so the drier the food the longer the cooking time in the microwave compared to other methods. And of course the amount of food cooked in a microwave will change the cooking time but will not necessarily change the cooking time on a stove top or in an oven.
    Steaming is a better way to cook vegetables, than boiling, as more colour, flavour and nutrients are retained.
    Phyl
    20th May 2016
    12:29pm
    I have used my microwave a great deal more since I bought a dish that basically changes microwave cooking into thermal cooking as in a conventional or fan forced oven. i get the speed and the economy of a microwave with the flavours and versatility of a conventional oven.
    Retired Knowall
    20th May 2016
    2:10pm
    Your calculations are flawed in that an electric element will cycle on & off when it gets to temperature, controlled by the simerstat. When calculating maximum demand of an electrical installation a 6 KW stove is derated by 50%.
    Also if you have a microwave that consumes more power with the clock I would be replacing it asap.
    Are you serious in stating that a 1000W microwave has a clock that draws more than 4 AMPS? The average clock that I have replaced on a microwave would not draw more than 100 mA.
    Eileen
    20th May 2016
    3:18pm
    I think taste is important as well, my veges steamed on a gas ring taste far better than those done in the microwave and cook more evenly. I always cook spaghetti sauce in the microwave it seems to turn out better, I use my electric oven for roasts and my slow cooker for casseroles, so I think it depends on taste nothing to do with cost. I would never cook oats on the cooktop, microwave every time, same with heating milk, cooking gravy etc.,too much cleaning otherwise.
    particolor
    20th May 2016
    8:52pm
    What's a Roast ? :-)