A story of induction hobs, electricity monitors & standby power consumption

Update January 2014: Before you read on, I need to make it clear that my induction hob DOES NOT actually use the amount of standby electricity that it appears to in this article.  I eventually tracked the problem down to an issue with the electricity Real Time Display meter (RTD), otherwise known as electrcity monitors, I was using to monitor my electrcity consumption.  Electricity real-time display meters do not cope well with appliances that have an inductive load – such as an induction hob, and consequently display the wrong, higher, power consumption as a result.  This is explained in detail in the update blog post I wrote subsequently and provide a link to at end of this article. I write this update as this blog post has been read over 35,000 times in a year and many readers are not reading the update to the story – hence are thinking induction hobs are really bad.  THEY ARE NOT!  So please, if you read this article, be sure to read the next in the series, that explains what is actually going on.

I do not want to remove this article as many people are finding this article because they have discovered the same ‘problem’ when using electricity meters to monitor consumption, hence I want to leave the story as it unfolded for me, so others can understand the ‘problem’, which is actually with the power monitor  not being able to cope with inductive loads, not the hob.

November 2012

I moved into my home some years ago and immediately set about refurbing the kitchen which was in a shocking state.  One kitchen appliance I had been coveting for a long while was an electric induction hob.  In my opinion it was a much more practical appliance than its gas fueled equivalent, with all its different bits that are tricky to keep clean and that persistent, nagging worry of whether you left the gas on or not.  More importantly, the induction hob is promoted as a very efficient way to cook, being around 30% more efficient than other types of electric hob.  At the time they were still a niche product, and relatively expensive to purchase compared to gas and other electric hobs, but I saw it as an investment.

So I went ahead and bought one from a very well respected, German manufacturer of kitchen appliances, and it was love at first use.  The induction hob is an absolute joy to cook with.  It is instantly responsive, it has a easy wipe-clean glass surface, you cannot accidently leave it on and there are no twiddly knobs or buttons, just a simple, minimalist, touch sensitive control panel embedded into the glass itself.  Although expensive I didn’t regret my purchase for a moment, and I was sure in the knowledge that I had also made an energy efficient purchase (at the time I was thinking ahead to when I would install PV, so my hob cooking would be both cost and carbon free eventually).

Later on, I was testing out a range of ‘Real Time Display’ (RTD) products for work, these are devices you attach to your electricity meter that give you minute by minute information on your electricity usage.  I then did exactly what people typically do when first installing an RTD, I went around the house, turning one gadget off after another, to see exactly how much power my individual appliances and gadgets were consuming.

It soon became apparent that there was something using rather a large amount of background power, and I couldn’t easily track it down!  Everything with a plug attached was switched off, including the fridge-freezer, and still there was about a 70-80 Watt (W) residual consumption.  Eventually I twigged – the only thing I hadn’t switched off at the mains was the induction hob.  Luckily the red isolation switch for the hob is easily accessible, and as soon as I turned it off, my RTD showed almost zero.

Imagine my shock?!  My wonderful, seemingly energy efficient induction hob was burning through a huge amount of power when it was, ostensibly, doing absolutely nothing! I was horrified, and checked, then double checked, my findings with a range of RTDs at my disposal. They all displayed the same bad news – my beloved hob was hugely wasteful in ‘standby’ mode.

At an average consumption of 75 W, and, by my calculation, taking off an average of one hour’s worth of actual usage a day which is a tad generous, in standby for 23 hours per day, I calculated my hob was using 1.8 kWh/day.  This was costing me, at an average electricity unit price of 14.5pence, nearly £100 a year to run, when it wasn’t doing anything useful!

The other finding was, as my entire annual electricity use was only approximately 1800 kWh/year (as calculated through my electricity bill), that my hob, whilst ‘idling’, was responsible for one third of my entire electricity consumption.

My “cunning” solution to this problem was to keep switching the hob off at the isolation switch, both overnight and we left the house each day.  This worked well for about a fortnight,  but after that  my hob suddenly stopped working!  There was nothing for it but to call out an engineer and luckily my hob was still under guarantee.  An engineer duly turned up and expressed surprise that such a new, typically reliable appliance should suddenly go ‘kaput’ just like that.  I acted as innocently as I could and did not reveal I was switching it off each day as I guessed that might have invalidated the warrantee.  He fixed it, and I decided that it wasn’t too wise to continue switching it off daily especially as I was coming to the end of my warrantee period, so I just decided to swallow the extraordinarily high running cost.

Roll forward to the present day.  Since installing PV panels over a year ago I have been monitoring both my electricity use and production carefully through the use of my PV enabled Wattson RTD meter, which gives me graphical breakdowns of total usage by minute, hour, day and month.  What I have noticed over the last twelve months is a gradual increase in my typical daily usage of electricity; even though we have not added any new appliances to the mix and are as careful as ever with our usage.  So, for example, instead of the typical 1800 kWh/year total consumption, I am now looking at around an estimated 2200 kWh/year over the past 12 months according to my Wattson real time display meter.

My first thought was that our 6 year old fridge-freezer was deteriorating in performance, so I checked that – no joy there.  I also checked our base load consumption (with hob switched off) when we were away on holiday for a week, that turned out to be a reasonable 1.6 kWh/day.  Then we went through the house, turning off one product at a time to see if we could identify the culprit – still no luck!  Until, yes you guessed it, we arrived to the hob.  Now, I was used to the hob’s 70-80W consumption pattern, so was expecting to see that level of reduction but, imagine my shock yet again when the RTD meter dropped by around 150W when we switched it off?!  We tested this thoroughly, and when we next went away we left the hob on, to check background consumption.  Sure enough, background usage as monitored by the RTD, over a 24 hour period with no-one at home, but with the hob left on, was around a total electrcity use of 5.5 kWh.  This means it is now using around 1200 kWh/year whilst idling, inexplicably the appliance seems to have suddenly deteriorated in performance?

Scaled up over a year, and with a new annual total electricity usage pattern of 2200 kWh, it appears to mean my hob is now responsible for over half my entire electricity consumption and is costing me £150 a year whilst doing absolutely nothing except waiting for me to come and turn it on through the touch sensitive control panel.

At that extraordinaily high running cost, I thought I’d look online to see if it would be worth my while buying a new, truly efficient model, but the problem is, as far as I can ascertain, no manufacturer currently displays the ‘standby’ function energy consumption in their publicly available product details for hobs.  Electric hobs will be soon coming under the EU energy label jurisdiction, and that does have a requirement for any ‘standby’ mode not to have a higher consumption load than 0.5W. My worry is if the mode that my hob sits in whilst waiting to be turned on at the touch control is defined and labelled something other than ‘standby’ mode, for example ‘quick start’ mode or something similar, then manufacturers can legally by-pass the standby requirement and continue to produce such inefficient appliances.

Please follow this link for an update on this issue.  The effect I was seeing on my electricity display meter  (RTD) is not actually real, and the electricity usage of my hob in standby mode is actually MUCH LESS than what I describe here due to a phenomenon known as the ‘power factor’.


35 comments… add one
  • Ted Lemon November 15, 2012, 3:51 pm

    Wow, that's a truly impressive energy vampire.   We have a Bosch cooktop that we bought just a few months ago, and we feel that the 7w vampire draw is a bit excessive.   I suspect that the reason yours draws so much more is that capacitive touch sensing technology has improved a lot in the intervening years.   I do wish that they would just use mechanical switches, like we did in ancient times, but apparently that is too much to ask…  

  • Neil Beresford November 17, 2012, 12:39 pm

    Very similar experience, just gone around the house testing electricity use by turning off individual appliances and have found my induction hob is drawing around 120w, when on "standby". Its only 3 months old from Ikea's Nutig range, and I will ring them next week to see what they say. After finding this out I did a Google search and found your article.
    In the mean time I will have to switch it off from the main cooker switch when we are not using it. Bizarrely I have an appliance on standby using around 10% of my total winter energy demand (including space heating) for the whole house.
    In another article from my Google search there was reference to where the 120w of electric energy is going as it must be producing another form of energy, presumably heat, which from my limited knowledge of basic physics would appear to be a valid point. However you cannot feel any perceivably warm areas of the hob on top or below it.
    Anyway probably more to this than meets the eye, but I will certainly be switching it off between its once a day use.

    • Paula November 17, 2012, 2:41 pm

      Hi Neil

      Thank you for your comment.  I knew thre would be others out there with the same issue, but I really didn’t expect the issue to be with such a modern version of the appliance, I thoghut it would be more of a legacy issue with older models!  That’s pretty shocking performance.  A word of warning about turning your appliance off every day; this is exactly what I did when I first found out how much it was consuming, it worked fine for about a week or two, then it completely died on me.  Luckily I was still within my warantee period, but I didnt own up to what I was doing as I felt they would have claimed I had invalidated my warantee by indulging in a ‘daily practice’ that wasn’t recommended.  Not sure what type of cover you have, but please be careful, especially if you are alerting the company to the issue as well.

      I’d love to hear about how you get on with Ikea and what thy have to say for themselves.  So please do keep in touch

      Best Paula

    • Jon Ball March 1, 2013, 4:04 pm

      I imagine, as inductive heaters work on the principle of an oscillating electrical field, this would be inducing a magnetic field (albeit a much smaller one) when it is on standby, which will partially result in heat dissipation to surrounding ferrous metal objects. With the relatively low current and high conduction of these materials I'm not surprised you would not notice it. But this is just speculation. In the same way that a coiled wire will waste some electricity from creating a magnetic field by acting as a solenoid (hence why you should always fully unravel retractable power chords when using them.

  • jan madgett November 30, 2012, 11:05 pm

    Hi About to bye an induction hob, we currently have a very inefficient halogen which we turn off off at the wall every time it is not in use, due to wandering kids fingers.  Could I suggest that you send your findings to Which magazine, they love this sort of thing and I will be watching the outcome.  By default everything with standbye we turn off, even the skye box……… Regards jan

  • Tim February 2, 2013, 3:38 pm

    Just done the same thing with my Lamona induction hob, shocked to discover that it is drawing 160w when idle.  That's £180 pa at today's electricity prices, about 30% of my usage.

  • Gordon February 8, 2013, 10:28 pm

    Hi, I have independently discovered the same issue with a brand new Whirlpool induction hob, with touch controls, which was installed six weeks ago, and subsequently found your report online.  Several measurements over three days, using an 'efergy' electricity monitor, show it consumes a variable amount, ranging from 70w to 130w, when switched off 'completely' using its own controls.  Other household devices, like TVs, hard disc TV recorders and Wifi consume only trickle amounts, typically less that one watt each, and many have touch sensitive controls.  Why is the consumption so high for the electronic touch sensitive control??

  • Janet February 13, 2013, 4:52 pm

    Having just bought an Ikea Folklig induction hob, but not unwrapped it yet, I wanted to check out this issue, since Ikea promotes induction hobs as the most energy efficient. I phoned Whirlpool (020-8649-5401) and got through to the Product Queries Department, gave them the model number, and was told that it uses 1 watt per 24 hours in standby mode. That seems OK to me so I'll cross fingers and go ahead with the installation!

    • Paula February 13, 2013, 5:39 pm

      Hi there

      Thanks for your comment. One watt per 24 hours seems suspiciously low to me; are you sure it wasn’t 1 watt per hour?  Also is your hob a touch sensitive model?  If it is, and it is 1watt/hour then that is very efficient.  Just to be clear though, the large wattage seen on real time displays are not strictly accurate, it is all to do with a complicated concept on ‘power factors’.  I have written a subsequent blog post on this issue, to be found here, if you are interested.

      • Jon Ball March 1, 2013, 4:17 pm

        Hi Janet/Paula, just to say, Watts are time independant 1W = 1 Joule / second (joule is a unit of energy), so 1W /hour is the same as 1W /24hrs, so I'm not sure 1W /hr is correct terminology. regardless, 1W standby is a rather negligable amount of electricity, so if that is the case, great!

  • Janet February 13, 2013, 4:57 pm

    I've just bought an Ikea Folklig induction hob, not unwrapped it yet, so contacted Whirlpool who put me through to their Product Queries department. They said that this model uses 1 watt per 24 hours in standby mode. That seems OK to me, so I'll go ahead and get it installed, cross fingers and wait for the next electricity bill!

  • Rob March 12, 2013, 5:09 pm

    I have recently had an induction hob installed (Beko  model HII 64403). I too am concerned by the excessive current being drawn on standby. When I used a power monitor to measure various devices round the house, the induction hob gave me a reading of 130 Watts on standby. So I told the household to always turn the hob off from the isolator switch when not in use. However when turning off or on it sometimes caused the RCD to trip.  This kept on happening. But its never tripped while in use. So we,ve kept the isolation switch on. Meanwhile will get the hob tested.

  • John May 8, 2013, 7:44 am

    Thank you for this ,this has made me think. Can you confirm that if I buy a induction hob with knobs ,not touch ,this would not draw power .  Thanks again.  John 

  • John May 8, 2013, 7:47 am

    It's very hard to find a induction hob with knobs. Belling seems to have two. 

  • viv walsh May 19, 2013, 7:45 pm

    Hi all
    Very interesting to ready u r comments.was recommended by kitcken designer to but induction but wad in two minds as perfer knobs.u r bloggs have made me decide that inductuon is nor fr me.
    Tks for a practical & great article !

  • viv walsh May 19, 2013, 7:47 pm

    Great article.induction been highly pushed by my kitchen designer.will think again.

  • Glenda May 21, 2013, 8:47 pm

    I have come across your site by accident but I am pleased that I have. I have been looking into buying induction hob for the very same reason, they are advertised as as fuel efficent. I never thought about the stand- by mode I will definitley look into this more now. Thank you 

  • John May 29, 2013, 8:54 am

    I have been reading various entries with interest, as we are about to replace our ceramic hob. Does this output on standby also apply to ceramic jobs? Our on off button is not easily accessible. Views welcome.r

    • Paula May 29, 2013, 9:37 am

      Hi John

      Thanks for your comment.  I don’t believe this power factor issue does pertain to ceramic hobs, I think it is just induction hobs.

      The best thing to check is the stated standby power consumption on any new cookcing appliance you buy.  And if it doesn’t have it stated, you could always write/email the manufacturer to ask them.  New hobs should be covered by the 1 watt standby legislation anyway (ie a simple standby mode should not consume any omre than 1 watt), it’s just if the manufacturer can argue that it is not actually a ‘standby function’ but something else, that they can get away with a higher consumption level.

  • agnes June 5, 2013, 8:32 am

    Thanks for the post. I had my heart set on buying an induction until I read this. Definitely a no-no for me now. 

  • Beverley June 17, 2013, 11:38 am

    Thank you for the post. Have read with interest as attempting to weigh up the benefits of ceramic verses induction for my kitchen – not sure about induction now  

  • paul corrin June 22, 2013, 7:01 pm

    did your friend explain why the hob went kaput? someone else also replied with the same thing. i suppose if you turned it off every night from new the company would get fed up with replacing the same part. i assume in the instructions it doesnt say that you are not allowed to turn it off after use.

  • Toney September 11, 2013, 11:02 pm

    Found this via Google…looked through saw the comments and re-read the updates. Very helpful as I am just getting into these types of cookers with induction cooking. Thanks for the information. Bookmarked.


  • Cindy October 30, 2013, 6:16 pm

    Thanks for shaing your experience. I was thinking to buy an induction hob but after reading your blog I changed my mind. Thx  cheers.

  • scooby November 11, 2013, 1:48 pm

    hi i have been a electrical engineer for 40 years and have just purchased a induction hob 6 sense by whirlpool . why should turning te unit off from a duel pole switch cause the unit to fail ??? , i switch all other appliences off rather than be on "standby mode" it makes no sense in engineering terms otherwise each time there was a power cut ther would be the same problem





    • Paula November 14, 2013, 9:17 am

      Hi Scooby

      Thanks for your comment.  I have no idea why it failed, but failed it did! I’d put it down to the fact that switching it on and off twice or more a day was not what it was manufactured to expect and it caused something to ‘go’.  All I know is, I had no problems with it before I started switching on/off daily, but then two weeks into doing so it failed. I haven’t done it since on such a frequent basis (only when I’m going away for a weekend or longer holiday) and it has been fine for eight plus years!

    • Samir December 9, 2013, 3:12 pm

      Ditto, cutting off the power from the source should not cause the hob to go kaput. There must be some faulty wiring in the concerned unit. and there is no sense in wasting precious electricity in the standby mode if we are to be eco- friendly

  • Mark December 4, 2013, 9:31 am

    Hi Paula,

    I've just purchased an energy monitor and also couldn't work out where the 'background' usage was coming from.  Turns out that about 100W is indeed coming from the induction hob.  It's a Lamona brand from Howdens.  No separate isolation switch in the kitchen, so I'm going to have to turn it off at the fusebox, otherwise it's costing me over £100 per year just to have it in stand-by!

    Kind regards, Mark

    • Paula December 4, 2013, 9:57 am

      Hi Mark

      You must read the update blogpost I wrote on this issue.  You hob is not actually using 100Watts, it is a feature of something called the ‘power factor’ that makes energy monitors display an inflated consumption figure for yuor induction hob.  Please read this update http://paulaowenconsulting.co.uk/2012/12/02/induction-hobs-the-question-of-standby-and-the-power-factor/ to get an explantion of what you are seeing on your energy monitor. Your hob is probably using about 20 Watts on standby.

      I have left the blog posts as they were written (in chronological order with links to the updated versions) so people who are seeing the same issue that I did can work their way through the story.

      Thanks Paula

  • Steve December 27, 2013, 4:09 am

    Excellent article, I was also looking at purchasing an induction hob. Looking at those standby costs, I may go to ceramic or stick to gas. I live in New Zealand where power costs much more than the good ole UK, so could not afford those background  usage charges.

    • Paula January 10, 2014, 3:29 pm


      Hi Steve

      You really should read the follow up blog post I wrote about this issue.  It is not as bad as it first seems.  THe porblem lay in my electricity monitor, that cannot cope with this type of inductive appliance, and give a false high reading of the power consumed.  Do take a look at this update post (link above), as it explains what is going on. Don’t be put off buying an induction hob, just make sure you ask what the standby consumption is.

      Best Paula

  • mike January 21, 2014, 10:08 am

    there is an induction hob made by zanussi that has knobs rather than touch it is only a two burner model cost is £215


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