Washing machine spin speed efficiency figures and drying costs
Here are some interesting figures (from an tumble dryer user manual) which give us an insight into the effectiveness of faster spin speeds . The figures are based on a 6kg capacity drum size and an efficient condenser dryer and show the residual dampness in laundry (cottons) after being spun at various speeds.
They also (much more interestingly) compare the difference in energy that’s required to tumble dry the laundry after spinning it at at say 1200 rpm compared with if it was spun at 1000 rpm or 1400 rpm.
Results would vary between different washing machines and tumble dryers, but they do give an accurate representation of the differences between the efficiency of different spin speeds, which I suspect is much less than most people are likely to expect, and the main point of this article.
| Spin Speed | Residual Dampness | Energy Used to Tumble Dry |
|---|---|---|
| 800 | 70% | 4 kWh |
| 1000 | 60% | 3.7 kWh |
| 1200 | 53% | 3.3 kWh |
| 1400 | 50% | 3.1 kWh |
| 1800 | 42% | 2.6 kWh |
(based on an A rated condenser tumble dryer. Newer dryers have higher than A ratings.)
These figures imply there is little advantage to paying much more for a 1400 spin washing machine over a 1200 spin washing machine, which I’ve seen as high as £50 more. These figures show that the difference in dryness between the two after spinning cottons is just 3% and it would cost only .2 of a kWh extra to tumble dry cottons spun at 1200 instead of 1400. Most other fabrics would have the same water extraction regardless of the washing machine’s spin speed because only cottons are spun at the top speeds.
Drying a load of cottons spun at 1200 would use 3.3kwh in electricity. If using a 1400 spin washing machine it would cost 3.1 kWh – a mere 2 pence cheaper (at time of writing). You would need to tumble dry such a load 2,500 times to recoup the extra cost in buying the 1400 spin washer if you paid £50 more for it. Note that energy prices are obviously getting higher, so this margin is likely to increase.
Spin speeds are good marketing tools
Washing machine manufacturers have long since used faster spin speeds as a way to increase sales and command higher prices. Most people believe faster is better, and “better” is worth paying more for, but the difference between an 1100 spin speed and a 1200 spin, or a 1200 and 1300 and even 1400 are pretty negligible. To make a significant difference in the amount of water extracted you have to have much bigger jumps than one to two hundred revolutions per minute.
Why does this matter?
Slower spin speeds mean –
- Cheaper washing machines
- Quieter washing machines
- More stable washing machines
- Longer lasting washing machines because there’s less wear and tear on the bearings, motor, carbon brushes, suspension etc.*
- Gentler on laundry
* The point about longer lasting washing machines has been somewhat diminished by the throwaway washing machine problem afflicting the majority of washing machines these days. This is because the price of parts is often extortionately high, which makes many of them artificially uneconomical to repair and prevents them lasting any where near as long as they would otherwise last.
Faster is definitely better but..
I appreciate that faster is better up to a point. Even if faster only gets a fraction more water out then arguably it’s preferable. But what I’m saying is that because faster comes at extra cost, and with several disadvantages it is not better per se – all the time, and for every one. As you get faster, the quality does not increase – but the cost, noise, how much it jumps around, wear and tear and even how long it will last all get affected so should be taken into account.
What about 1800rpm?
It’s only when you jump from a 1200 spin washing machine (the current most common speed) to 1800 rpm that you see a more tangible benefit. If comparing the costs of tumble drying after spinning at 1800 rather than 1200 then it would use 2.6 kWh instead of 3.3 kWh. That equates (using the 10p per kWh figure) to 26 pence instead of 33 pence – a saving of 7p. However, an 1800 spin washing machine could easily cost £100 more than a 1200 spin. This would mean someone tumble drying 2 or 3 loads a week would take about 9 years to get a £100 premium purchase back. You should also factor in the fact that an 1800 spin washing machine may be subject to more wear and tear because of the extra speeds involved.
Of course this argument is based on tumble drying laundry. If not tumble drying then the only difference is that it will take a bit longer to dry on the line or in the spare room next to the radiator but at no extra cost. In this scenario the cost issue is replaced by a convenience issue, which for some will be negligible though for others it could be more significant if having laundry drying in the house is inconvenient.
What about the argument that using less electricity is better for the environment?
That’s a fair point. From an environmental point of view it is better that we all pay £100 more for a washing machine and use less electricity if tumble drying – even if the electricity saved is a fraction of the extra costs buying the faster spinning washer. This is a very different argument to the personal economic considerations covered above and is based on the premise that regardless of the cost to the consumer, the less electricity we use the better.
However, as with many environmental arguments, the whole picture needs to be taken into account and all too often it isn’t. If faster spinning washing machines aren’t built to a high enough standard, and break down more often, or just don’t last as long, then the whole environmental benefit is compromised and the scales could even tip the other way.
Many of the most common washing machines are not made to a high enough build quality to cope with very fast spin speeds. They can be noisy, bounce around too much, refuse to spin many loads at full speed because of over-protective and less sophisticated out of balance systems, and parts can wear out or fail quicker and more frequently.
Summary
For the average person buying an averagely built washing machine, 1200 should be the best compromise between drying efficiency and cost, noise, stability and wear and tear. The figures above show that a 1400 spin washer doesn’t get that much more water out. I wouldn’t say avoid a 1400 but you would need to decide how much extra you are paying for the extra 200 rpm and if the extra cost is worth it. If buying a cheap washing machine, 1600 is way too fast in my opinion because they aren’t built any better than the 1000 spin versions they used to make. Maybe even 1400 is too fast for some washing machines these days. (related: Washing machines exploding – what’s going on?)
If you use a tumble dryer excessively it may be worth considering a higher spin speed but again, the figures show that you may need to jump to an 1800 spin to get a significant difference, and currently an 1800 spin is likely to cost so much more it’s debatable whether you will save much money at the end of the day unless you tumble dry all the time. It will still save some drying time though.
At the end of the day, as is often the case, trying to look at the bigger picture is complex and there are many variables that make it impossible to advise a common best tactic. The main thing is to not get carried away thinking faster is definitely better and ask why manufacturers make washing machines that spin at so many different top spins when surely there has to be an optimum that should mean all washers should spin at the same ideal spin speed. It costs virtually nothing extra to make a washing machine spin at a top spin of 1000, 1200 or 1400, with spin speeds often set artificially by simply configuring the same pcb differently.
Related:
- Washing machine spin speeds
- Are Washing Machine Spin Speeds A Con? (Forum discussion)
- Find out which are the best washing machines – 1 month trial offer is available for just £1
The arguments in this article are based on electricity charges being at certain (quoted) rates. If electricity charges increase significantly it may affect the argument. At the end of the day if you can follow the argument and factor in the amount you are paying for your electricity you can decide for yourself.
This has been brilliant information. I ordered a 1200 rpm machine and was worried about the dryness of the clothes and was going to cancel it and pay an extra £200 for the 1400rpm machine. After reading this I am definately not going to waste my money !!! Thank you, fantastic information.
I have to echo the comments left by Donna above. Your site has been fabulous research info and I know exactly what i am looking for in my price range now. thanks.
Many thanks.
My washing machine is an 800rpm spin and is perfectly adequate. I had a 1300rpm previous to this and the laundry felt virtually no drier even the towels, and the tumble drying times are just about the same give or take 5 minutes! So extra fast speed would be a waste of time IMO.
The drier is a Crosslee White Knight “A” Class if you are wondering, not used in the 8 hour mode though, but still cheaper to run than a normal drier.
HTH,
Oliver.
Some years back we were using a Hoover 1300 condenser washer dryer. I can’t remember how it came about but we swapped it for a Hotpoint washer dryer which was much newer as I’d somehow acquire it for nothing. I hadn’t realised it was only an 800 spin. However, Mrs. Washerhelp never complained once despite the fact that her old one spun 500 RPM faster.
You can trust me when I say she would have been more than happy to complain if she had found her washing was coming out much wetter.
I do personally believe that 1200 RPM for cottons is probably an optimum spin, everything else can be spun at 800 rpm perfectly adequately and with less wear and tear on the laundry and washing machine. There is nowhere near the difference in real-world results that manufacturers would have people believe.
I’ve maintained for years that spin speeds are merely a marketing tool, and that the slow evolution of an extra 100 revs at a time mimics the same ridiculous managed-evolution of the good old bladed shavers. For years all shavers had just one blade, then it was “discovered” that two blades shaved even better. Two blades ruled until it was “discovered” that three is even better. Then miraculously someone discovered that four is even better still. Then someone launched a 5 bladed razor and so on.. According to research I found, the single blade razor dominated for 70 years, the twin blade shaver lasted 27 years and the triple lasted 5 years – does it really take all this time to discover an extra blade is better? Or do they just introduce them every so often to revitalise the market?
It’s pure marketing designed to stimulate new sales and get one up on competition. I don’t believe shaver manufacturers couldn’t discover the optimum blades needed for the best shave and stick to it and I can’t believe washing machine manufacturers don’t know which is the optimum spin speed for cottons and then make all their machines use it. The only reason for not doing so – bearing in mind it costs virtually nothing extra to make a washer spin faster and many are actually deliberately made to spin slower using resistors – is to be able to offer a perceived extra value feature people believe is worth paying more for.
thanks for explaining this to the uneducated/uninitiated. My machine broke yesterday. With a family of 6 there’ll be a new washing machine in tonight (machine has probably reached its life span) – you just saved me at least £50.
If the intention is to make clothes drier after spinning, why not use an old fashioned spin dryer, as they would spin clothes at about 2800 rpm! Maybe faster? Then put the clothes into a tumble dryer and see how quick they would dry.
I’m sure the old spin dryers (and the spinners in twin tubs) had faster spin speeds because the drum is mounted vertically? I wonder why washing machines or washer dryers don’t spin as fast as the old spin dryers? I know some launderettes have a spin dryer which customers use after the clothes have been spun in the washing machine!
The spin dryers used very fast but small motors mounted very close to the drum pulley via a very small belt. They could run at high speeds but couldn’t turn a heavy drum full of wet laundry. They had very small gear/pulley ratios so less speed was lost between the spinning motor and the pulley it was turning.
Front loading drums needed a bigger pulley to reduce the strain on the motor when turning large wet loads full of water and it had to be connected by a much larger belt. Both of which means a lot of speed is lost between the rate of the revolving motor and the subsequent revolving drum. The motor on a front loading washing machine probably spins at similar speeds to the old twin tub, it’s the gearing that results in lower drum speeds.
This is a great post. Everyone should read this before they go out and buy a new dryer or set. In other words don’t get duped by the slick salesman trying to upsell you on the faster spin cycles. As you mentioned you would have to do 2500 loads of laundry to recoup that expense. Your dryer will more than likely be broke down and gone by that time.