Monday, 1 September 2014

Saving the planet?

Interesting article on the BBC "High-powered hairdryers under threat as EU considers ban" today.

The couple of points I take issue with are :-

(a) Restricting kettles. Obviously, it makes no sense whatsoever to restrict the power rating of a kettle. The energy to boil an amount of water is going to be the same regardless. The article does not say the "restriction" would be on power ratings, but that does seem to be the implication. Thankfully the referenced report is slightly saner and talking of (wasted) thermal mass of heating element and heat lost externally whilst in use, and so on. Better designed kettles I have no problem with.

(b) The comments from hair dressers - I tend to agree that, like kettles, if you have lower power dryers then they will be used for longer, and not really help. But also, what seems odd is that I would expect professional hairdressers to have no problem buying "commercial" hair dryers which I would hope are not subject to the same restrictions.

We had this when replacing our tumble dryer recently. It was a powerful one, but the manufacturer don't do them any more (not in EU anyway) because of these silly rules. Again, if less power then longer to dry stuff, so why? In fact, many things are not run on the highest temperature anyway - the higher power is probably because it is bigger, and hence means fewer loads. Ultimately it takes an amount of energy to dry clothes, so reducing power does not help. What you need is greater efficiency in getting that energy to the clothes.

Anyway, the answer was simple, I just purchased a "commercial" tumble dryer. This allowed me to choose from a range of way more powerful devices, actually expanding my choice rather than reducing it (having not considered a commercial appliance before).

I am sure the same will apply to kettles, hair dryers and everything else they are restricting.

12 comments:

  1. AIUI, the whole point of the legislation is to try to encourage greater efficiencies - be it with hairdryers, tumble-dryers, kettles or whatever.
    I seem to remember reading a quite from Dyson who were commenting on the power reduction required in vacuum cleaners - they said something to the effect of "Doesn't affect us - our machines already use less power than the limit and they're more effective than our competition's machines - even those high power models which can't be sold any more".
    The same applies to kettles. Yes, it will always take one calorie to heat 1cl of water 1 degree, but a metal kettle will always use more power than an insulated plastic one, due to heat losses, for example.

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  2. Similarly with the vacuum cleaners. If I have a 900 watt cleaner than it may take a couple of passes to clean the carpet, I may have to wiggle the hose into the nooks and crannies for longer to suck up all the muck.

    There are more powerful vacuum cleaners because they generally do a better job (notwithstanding inefficiencies) and reducing the power means a unsatisfactory performance which can mean more use of the device to achieve the desired result.

    Also, these devices are not usually used all that much (depends on how OCD you are about it I guess ;-) so I am not sure of the overall savings. Legislating about standby power of set top boxes I get, but vacuum cleaners? Hairdryers?

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    1. A lot of high wattage vacuum cleaners are inefficient, and produce poor suction per wattage. This is the point Dyson have been making. My aunt bought a high wattage cleaner and took it back, it cleaned so badly compared to her previous Dyson. Lesson learned, she bought another Dyson and is very happy with it.

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  3. I agree that it's a bit silly for kettles and vacuum cleaners, which'll simply take longer (and use the same amount of power) to achieve the desired result.

    I can see it might be justified for tumble driers. Many people run the tumble drier for - let's say - 2 hours, because that's how long they've always run it in the past to get dry clothes. It may only actually 'need' to be run for 1h30.

    How many people actually bother to work out how long they need to run the drier for in order to achieve the desired result? I appreciate many of us reading this probably *do* work it out (I always run the drier in 20 minute increments, checking dryness regularly, when I'm on holiday and using an unfamiliar machine, for example), but back in the non-tech world, I suspect most people don't bother.

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    1. Our dryer runs until the sensor says the clothes are dry - simple as that!

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  4. It's interesting that all these seem to be targeting consumers, but I would guesstimate businesses use a lot more electricity unnecessarily: shops leaving lights on over night (interior drinks machines are good at this and many business districts) and how efficient are many industrial machines (I used to work at a printing company where, a press had a fault and it blew the local electrical substation: so quite a power draw). But, of course, we can't inconvenience businesses or even make them install solar panels.

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  5. Having just spent a week in Florida, seeing all the Aircon running 24/7 with the doors wide open, unnecessarily large cars, enormous food portions and domestic appliances built for convenience rather than efficiency I'm not at all worried about the efficiency of European consumer goods.

    I just want a washing machine that takes 12 minutes like an American machine rather than the 3 hour 'Eco' wash on my machine. I'll hang my washing outside to dry to make up for the extra energy use (banned in a lot of America in case it decreases house prices!) and drive my 50mpg small family car.

    Lets just build some nukes and insulate our homes properly, that will do more for climate change than all this power limiting nonsense.

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  6. IIRC, it's more energy efficient to spend a long time drying, but at a lower temperature, than it is to dry quickly at a higher temperature. The underlying physics is that drying with heat relies on the water evaporating, while the losses are caused by heat transfer to the general environment; if you can reduce heat transfer to the general environment without reducing the water evaporating, you increase efficiency, and a lower temperature for longer is one way to do that.

    Having said that, I think the best example the EU could follow here is not banning on power output, but doing what they did for lightbulbs; mandate a minimum efficiency (on a standard test cycle for things like vacuum cleaners and tumble driers), and leave it up to manufacturers to work out how to handle this.

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    1. Leaving things up to the manufacturers doesn't seem to have worked well for labelling energy efficient bulbs though (to be fair, I don't know what the EU rules are regarding labelling).

      A quick look around the shelves at energy efficient bulbs of various varieties that are labelled as "equivalent to X watts" and they are all over the place - some of them emit the same number of lumens as an X watt tungsten bulb, some emit the same number of lux.

      CFLs are well known to over-estimate their equivalence, which is one reason they have got such a bad name - people bought an "equivalent to 100W" CFL to replace their 100W tungsten bulbs and the result was usually as dim as a 60W tungsten!

      Also, measuring bulbs "equivalent to" a tungsten all the time is bonkers - if I'm replacing a halogen GU10 bulb with an LED GU10 then I don't care what kind of tungsten bulb the LED bulb is equivalent to, I care whether it will do the same job as the halogen bulb I'm replacing! (And whilst the answer is certainly "yes" and LED GU10s do replace halogens very well, you really need to do your research to make sure you don't end up with a very dim narrow-angle beam due to the confusing labelling)

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  7. I saw this in a Telegraph article and immediately thought the same as you - it takes 336KJ to boil a litre of water from 20°C and reducing the power requirements of a kettle isn't going to change this (in fact, it would make it worse due to thermal losses while it took longer to heat; and would probably increase the incidence of "reboiling" - where people put the kettle on and then wander off to do something else while it boils, forget about it and then come back later and reboil it).

    Then I read the actual study and realised that the Telegraph were grossly misrepresenting the facts - nowhere in the study do they suggest restricting the power of kettles. The study is actually pretty sensible - they are interested in improving durability (reduce the need for regular replacements) and efficiency (reduce thermal mass, improve wall insulation, reduce the time it takes the autocutoff to activate, etc).

    So as usual, it seems the press are going off on an anti-EU rant with no solid foundation, and anyone not willing to glance through a 200-odd page report is going to believe them. Sad. :(

    I can't really comment too much on hair dryers and the like. It seems unlikely to me that just increasing the wattage will produce a proportional reduction in drying time. There is probably a non-linear relationship with a sweet spot for efficiency. I would hope that the people doing the study would figure out where the sweet spot is and then see if the manufacturers need to be nudged towards it a bit. The public often take a "more is better" attitude, so the marketing people may push for these appliances to be unreasonably powerful just because they sell better, even though they are no better at the job - regulating that kind of idiocy isn't a bad idea.

    The other one the Telegraph pointed at was limiting the power requirements of smartphones. Reading the report, they did say that there was scope for reducing the power requirements, but also stated that no regulation was necessary since the vendors are _already_ trying to reduce power requirements in order to extend battery life. Again, they were mostly interested in replacement frequency, etc. which is certainly a problem in the phone market since the MNOs push people into upgrading perfectly good phones by offering (not-really-)free upgrades.

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  8. I'm for appliances that work as well for less energy use - but against banning them where there really isn't something that works as well. That has to be a consideration - I won't buy a poor appliance, but I will buy a good efficient one.

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  9. I recently bought a dishwasher and was horrified to find the wash cycle takes 2.5 hours, compared to 45 minutes on my last one.

    The reason for this appears to be making the device 'eco friendly' - they had to reduce the amount of electricity/water used per hour, and the obvious way to do that was to slow it down. The washing machine from the same brand does exactly the same trick.

    Lesson learned - When that is replaced I'll make sure I read carefully and avoid the marketing bluster, but it does mean I'll be seeking out the non-Eco products in the future, since they don't really use less energy.


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