Do you use electric clothes dryers?

BooJewels

getmore4less said:

BooJewels said:

Thanks @getmore4less - I'm not in the market for a new washing machine at the moment, but I'll bear it in mind when I am.  I had an old standalone spin drier when I first married and that was a cracker.

We still have one hidden in the rubbish in the garage, thinking of resurrecting it,  check it over as not been used for over 20years, then see if it can reduce the moisture content of the stuff that will still go in the HP dryer, can measure if it saves any electric.

I was thinking about that yesterday - how much electric does spin drying use compared to tumbling or other heated methods.  I would guess, with the absence of heat, that the spinning is much more economical.   I just looked at a modern standalone spin drier and that claims to be 30w per cycle @ 2,800 revs.  I think my washing machine is about 1,300-1,400 revs.  My sister has a hand wound one and even that gets more moisture out than you can by wringing.

Even though I use my drying rack, I do run the spin cycle around three times (I often open the door and rearrange the contents, especially towels) before taking them out - they are tangibly less wet for doing so.  Before electricity was such a concern, this was simply to reduce drying time and the amount of moisture I was releasing into the atmosphere inside.  But as I now live alone, I often just hand wash small loads then spin them in the machine.

getmore4less

BooJewels said:

getmore4less said:

BooJewels said:

Thanks @getmore4less - I'm not in the market for a new washing machine at the moment, but I'll bear it in mind when I am.  I had an old standalone spin drier when I first married and that was a cracker.

We still have one hidden in the rubbish in the garage, thinking of resurrecting it,  check it over as not been used for over 20years, then see if it can reduce the moisture content of the stuff that will still go in the HP dryer, can measure if it saves any electric.

I was thinking about that yesterday - how much electric does spin drying use compared to tumbling or other heated methods.  I would guess, with the absence of heat, that the spinning is much more economical.   I just looked at a modern standalone spin drier and that claims to be 30w per cycle @ 2,800 revs.  I think my washing machine is about 1,300-1,400 revs.  My sister has a hand wound one and even that gets more moisture out than you can by wringing.

Even though I use my drying rack, I do run the spin cycle around three times (I often open the door and rearrange the contents, especially towels) before taking them out - they are tangibly less wet for doing so.  Before electricity was such a concern, this was simply to reduce drying time and the amount of moisture I was releasing into the atmosphere inside.  But as I now live alone, I often just hand wash small loads then spin them in the machine.

I will test the cost of an extra spin in the washer on my next wash.
Could split the load in two and give 1/2 the extra spin then dry each separately(problem is got to let the dryer cool between dries for a fair comparison)

I have been testing the plugged in off state, the washer use 0.75wh and the dryer 8wh a day with the £0.35/kwh I can save  £1  a year  turning them off at the wall when not in use(most of the time)

BooJewels

@getmore4less - do they have digital displays or clocks to be using that much juice when not in use?  I'm going to have to get an energy monitor to start assessing things more carefully myself.  My machine is pretty basic, so no digital display or LED lights.

Out of curiosity, as my washing machine was doing a load of towels etc., I decided to time the additional spin cycle and work out the cost (I had no idea how long it actually took - 'a few minutes') - this is done from theory, not actually measured.  My machine is apparently a 1,200 rpm spin and the cycle lasted 9 minutes 50 seconds from switch to click of the door lock opening, so let's say 10 minutes, being generous.  The motor is rated at 350 watts - so 58.3Wh for one additional spin - at 34p/kWh, that's a smidge under 2p per spin.  I'm very happy about that, I might have guessed more than that.  So if I do hand wash and rinse, using hot water through my combi boiler and then just spin in the machine and dry on my rack, I'm probably doing it about as cheaply, energy wise, as possible.

Would 2 x 10 minute spins at 1,200 rpm, have the same water removal power as one 10 minute spin at 2,400 rpm?  The figures I posted earlier would suggest that the electricity used would be very similar, but does the faster spin shift more water molecules?

victor2

BooJewels said:

@getmore4less - do they have digital displays or clocks to be using that much juice when not in use?  I'm going to have to get an energy monitor to start assessing things more carefully myself.  My machine is pretty basic, so no digital display or LED lights.

Out of curiosity, as my washing machine was doing a load of towels etc., I decided to time the additional spin cycle and work out the cost (I had no idea how long it actually took - 'a few minutes') - this is done from theory, not actually measured.  My machine is apparently a 1,200 rpm spin and the cycle lasted 9 minutes 50 seconds from switch to click of the door lock opening, so let's say 10 minutes, being generous.  The motor is rated at 350 watts - so 58.3Wh for one additional spin - at 34p/kWh, that's a smidge under 2p per spin.  I'm very happy about that, I might have guessed more than that.  So if I do hand wash and rinse, using hot water through my combi boiler and then just spin in the machine and dry on my rack, I'm probably doing it about as cheaply, energy wise, as possible.

Would 2 x 10 minute spins at 1,200 rpm, have the same water removal power as one 10 minute spin at 2,400 rpm?  The figures I posted earlier would suggest that the electricity used would be very similar, but does the faster spin shift more water molecules?

Don't forget you've also got the pump running on a spin. Presumably not all the time, but it's energy consumption nevertheless.
Far better to get a monitor and see what each particular cycle uses. Average them out to account for variables such as incoming water temperature.

BooJewels

victor2 said:

BooJewels said:

@getmore4less - do they have digital displays or clocks to be using that much juice when not in use?  I'm going to have to get an energy monitor to start assessing things more carefully myself.  My machine is pretty basic, so no digital display or LED lights.

Out of curiosity, as my washing machine was doing a load of towels etc., I decided to time the additional spin cycle and work out the cost (I had no idea how long it actually took - 'a few minutes') - this is done from theory, not actually measured.  My machine is apparently a 1,200 rpm spin and the cycle lasted 9 minutes 50 seconds from switch to click of the door lock opening, so let's say 10 minutes, being generous.  The motor is rated at 350 watts - so 58.3Wh for one additional spin - at 34p/kWh, that's a smidge under 2p per spin.  I'm very happy about that, I might have guessed more than that.  So if I do hand wash and rinse, using hot water through my combi boiler and then just spin in the machine and dry on my rack, I'm probably doing it about as cheaply, energy wise, as possible.

Would 2 x 10 minute spins at 1,200 rpm, have the same water removal power as one 10 minute spin at 2,400 rpm?  The figures I posted earlier would suggest that the electricity used would be very similar, but does the faster spin shift more water molecules?

Don't forget you've also got the pump running on a spin. Presumably not all the time, but it's energy consumption nevertheless.
Far better to get a monitor and see what each particular cycle uses. Average them out to account for variables such as incoming water temperature.

I was only interested in the spinning bit of it - and I did say it was only 'out of curiosity' and 'theoretical', not actually measured, as I don't have an energy monitor.  And the manual only gives the energy consumption for the motor and heater, so there's a limit in how much I can calculate anyway.  If it uses 2p or even 5p per extra spin, that's close enough for me to be very worthwhile doing.  I'm only doing it a couple of times a week, so it's not a big deal either way.

And if it's done before using a tumble drier on the same load, I would be prepared to wager that the cost of the additional spin will be 'definitely-worth-doing' less than the drier time to remove the same volume of additional moisture - just by removing heat from the equation.  If you're doing laundry for a large family and many times a week, it might be very be worthy of consideration - when I've seen figures quoted in the energy forum for tumble driers well in excess of £1 per load!

getmore4less

OH did one of her washes and an extra spin used about 45wh(0.045Kwh)
edit : seen your post it was a 10min cycle.

The tumble of some of that load took about 0.530kwh

A controlled experiment might be going a bit too far.

Say a load of towels do a non wash(bucket) to get them wet.
first day one spin cycle and dry.
next day two spin cycles and dry.
third day three spins and a dry.
Between each spin take them off the sides of the drum

getmore4less

BooJewels said:

@getmore4less - do they have digital displays or clocks to be using that much juice when not in use?  I'm going to have to get an energy monitor to start assessing things more carefully myself.  My machine is pretty basic, so no digital display or LED lights.

Both machines have displays but they have a time out of a few mins,

The 0.75  and 8 are the most off they can go before turning off the supply.

Still a lot less than a smart switch uses

The dryer maxes out at 700w and the washer 2.5kw when heating water, can run together off the same switched socket.

BooJewels

It looks like the spin cycles were very close in terms of energy used, which is a good plausibility test. 

I suppose an easy test (we're not writing a scientific dissertation here), now you know how much juice it uses per spin, is to spin a regular load a couple of times extra and then see how much you can knock off the tumbling time to get to the usual level of dryness - so if you save 10 mins in the tumbler, if the cost of that is greater than the spin cost, you're on to a winner.  If a tumble cycle is something like 4kWh and you can cut 10 minutes, that might be 23p saved for 4p spent extra by the washing machine, for a smidge more effort.

I wondered if you could judge the relative dryness after additonal spinning by weighing the item - say a small towel - dry, then after each spin cycle?  I've only usually done 2 extra cycles - that was the point where it didn't feel like I was likely to get them noticeably drier. You can really feel it between spin 1 and 2, less so after that.

ETA: we were obviously typing at the same time - if your dryer is 700w, my numbers are way off - I was going by numbers posted in the energy forum recently - I've never had one myself.

getmore4less

The tumble dryer is a HP and the max instantaneous power use I have seen is 700w (hp, air fan, water pump lights and electronics)

One thing to remember when looking at spec sheets for tumble dryers and cycle power use is the retained moisture starts at 60% to do the testing.

Most washers are better than that these days(A rated is under 45% on the A-G scaling).
Many don't bother checking

Our Bosch(2014) is rated at B - 48% for cotton, better machines are getting close to 40% these days

that's probably why the dryer usage is well below the spec kwh and mins to dry.

The washer is rated at 0.1w in its off state and 1.45w in ready state  
I am getting lower for the off state and around 1.5w-2w for ready state

I have some way to go as we use easy 4,000kwh a year around 11kwh a day need to get that down just have not been that bothered.

The energy audit is to work out where it is going and look for some wins that are not inconvenient.

AdamDoubleG

I joined the forum specifically to ask a question sort of connected to this one. Basically, I'd really be interested if anyone could give some advice on the best way to dry washing now that summer is gone.

As at least one person has mentioned already, I often run an extra spin cycle on the washing machine because I feel like I've heard this is a good way to get extra water wrung out before removing it from the machine. I wasn't sure if this was true or just a waste of electricity?

We are hanging washing outside as much as possible but even if it doesn't rain, it's not really fully drying quickly enough.

Once we bring it inside, what's the best way to dry it? Using our tumble drier or hanging it up and putting the central heating on? Obviously it would be nice to have the heating on as we will be warmer as a bonus.

Is it advisable to buy a dehumidifier or is that going to cost more money than it saves? How does running a dehumidifier stack up against having the heating on or running the tumble drier?