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Kettle review

I notice the boil performance score is the speed to boil 1L of water and shown as a percent, but the actual times are omitted from the review. If I missed it, where please. If the fastest was 100% it could be discerned one at 75% could take 1/3 more time, so that is useful, but none are 100% so that is not your algorithm.

If ‘one’ takes 2 minutes and ‘another’ 2 minutes 20 seconds it might not be interesting. If the ‘another’ took 4 minutes it might be a deal breaker compared to ‘one’.

Has oversimplification happened where useful information has been filtered out?


I don’t want to be waiting for the kettle to boil as long as some seem to be indicating by their boil score. I use a kettle when I want a quickly boiled hit of hot water, I am guessing that almost all use elements that take as much advantage of the current supplied to heat the water. Some obviously do it far better than others and yet do not rate a recommended.


Thanks for the feedback @grahroll! I’ll pass this on to the testers to see if they can provide some clarity behind the scoring criteria.

Hey @TheBBG, you can find the boiling times in the test results section when you select or compare products in the review.


Methinks I am going blind. Thanks :slight_smile:


Maybe a better performance measure is efficiency…namely energy/electricity consumed per litre of water. This may be more of an interest to consumers than how quick it boils water.


If there was any difference between the candidates.


I think both. There is a good reason why I will never willingly move to any country with 110V power - boiling time takes on a whole new meaning !! :slight_smile:


4,184J per kg of water per deg C temperature rise.

One litre of water at tap temperature 20-25C is approx 1kg.

To heat 1.0l of water from 20C to 100C requires 80x4184J = 334.7kJ
For a 2,000W kettle, time to boil 334.7/2 = 167.4seconds.
(IE 2 min 47 sec).

For 2l double the time.

It’s interesting in the Choice review just how long some kettles took.

The big question is whether those with low efficiency were loosing (wasting) energy, or performed with lower than specified wattage? Which is what I read several of the more recent posts to be asking. There is an energy efficiency score in the detailed test results for each kettle.

Perhaps a more detailed explanation on how the calculations were performed might be of benefit in improving understanding? In particular how the bench mark for time to boil was set. These scores do not align with the comparative time taken to boil. The relative efficiency of the majority of the kettles is in a very narrow range. Close enough to suggest that in everyday use it is minor to insignificant.


Hey @grahroll, passing on a reply from Kim, the team leader of the household department.

We realise some people have different priorities when it comes to the very important issue of making a cuppa so people can filter the scores to help them make their own decisions.

Some years ago our weightings didn’t tend to show much of a differentiation between the kettles. Most were noisy, for instance. So we decided to look at the ‘ease of use score’ as one differentiator - it’s got to score at least 80% for this, as well as high enough overall, to be recommended.

The boil performance score is based on how long it takes to boil one litre of water. The kettle with the 66% score is still an OK score, and it took 3 min 30 seconds to boil one litre with that model. As a comparison, a model that scores 80% for this will boil one litre in 3 min 7 seconds.

We test our kettles in a lab environment with regulated voltage and temperature/humidity controlled conditions so that they can be compared fairly. In reality, the time it takes to boil water will vary depending on how cold the water is when you put it in, how much is in the kettle, the ambient temperature, and even your home’s voltage. The performance score only takes up 10% of the overall score, as they’re all within a similar 30-40 second ‘ballpark’. So, you might have your water a few seconds faster, but the kettle might be awkward to hold, fill or pour, for instance, or you mightn’t be able to see the markings on the kettle etc.

Hope this information helps provide context on our scoring.


Thank you & Kim for the provided information, it helps clear up any misunderstandings.