Heat pump tumble dryer

[Onthespotwelding]

Hi all

I’ve been looking at simple ways to save energy.

I recently saw an episode of the gadget show which showed a heat pump tumble dryer uses 80% less energy than a conventional one, and they aren’t that expensive to buy!

 

[Kayos]

Yes, heat pumps take (for example) 1kw of electricity and output 2-3kw of heat

 

[merryman]

I use a washing line, it costs nowt.

 

[brightspark]

Yes, heat pumps take (for example) 1kw of electricity and output 2-3kw of heat

so why dont they make heaters with them. you cant get out more power than is put in

 

[julianf]

Ours is a heat pump (in the process of failing, but nothing to do with the heat pump bit)

Theyre clever. Rather than heating up a whole load of air, and then dumping it, they just recirculate the same air, manipulating it around the distillate point. So they take a lot longer, but use less power.

 

[julianf]

so why dont they make heaters with them. you cant get out more power than is put in

You could use the 3kw to run a generator, to run the tumble dryer, and you would never need to buy in power ever again.

(sorry Kayos, its only in jest : )

 

[brightspark]

Ours is a heat pump (in the process of failing, but nothing to do with the heat pump bit)

Theyre clever. Rather than heating up a whole load of air, and then dumping it, they just recirculate the same air, manipulating it around the distillate point. So they take a lot longer, but use less power.

so they dont put out more power than is put in the 1 kw of heat produced is just used more efficiently before exhausting

 

[Domdom]

so why dont they make heaters with them. you cant get out more power than is put in

You sort of can, although technically you are correct. Basic law of physics, energy cannot be created etc

But, traditional heaters are grossly inefficient. What we understand to be 3kw of heat is actually highly variable, just all measured against input power.

Heat pumps are just 3 or 4 times more efficient. 1kw of electricity to pump the heat around just like a reverse air conditioner elicits about the same heat output as a 3kw traditional heater.

 

[Lazurus]

Reviews say it can be up to 11 years to get payback on the initial cost

 

[brightspark]

Reviews say it can be up to 11 years to get payback on the initial cost

providing it lasts that long

 

[julianf]

Reviews say it can be up to 11 years to get payback on the initial cost

Ours was £40.

Some friends, later, bought the same model with a different name on the front, for £50. Both purchased used, and are (almost) still working (the fault with ours is with the drum spinning, not the condensing part)

 

[knighty]

Yes, heat pumps take (for example) 1kw of electricity and output 2-3kw of heat

so they dont put out more power than is put in the 1 kw of heat produced is just used more efficiently before exhausting

heat pumps do put out more heat than electric you put in.... they're just pulling in the heat from elsewhere is all

 

[knighty]

my parents bought a heat pump tumble dryer... but my dad refuses to let it be used because he says it takes too long and uses too much electric :-s (he's a bit old fashioned)

before they moved the tumble dryer was gas so I think they were spoilt with that :-)

 

[Newlands]

If you want to save 100% of the energy that a conventional tumble dryer uses, at a capital cost of around 1% of the cost of the tumble dryer, there’s a fantastic device available called a washing line. No maintenance costs, lasts for around 20 years, only requires some clothes pegs, doesn’t need fluff and condensate emptying and no risk of fire.

 

[brightspark]

heat pumps do put out more heat than electric you put in.... they're just pulling in the heat from elsewhere is all

like where . our drier is out in the cold so draws in cold air be like vaccum cleaners with less powerfull motors that dont suck as hard to save electric. but it dont because it takes longer to suck the crap up negating the saving `

 

[Domdom]

It’s the heat differential. Even cold outside is, say, 5 degrees. A heat pump just takes a few more degrees out of that.

 

[keithski122]

I use solar power for drying our laundry.

 

[julianf]

like where . our drier is out in the cold so draws in cold air be like vaccum cleaners with less powerfull motors that dont suck as hard to save electric. but it dont because it takes longer to suck the crap up negating the saving `

Yours is out in the cold, so sucks in cold air, heats it up to "hot" and then throws it out again.

A heat pump unit starts with cold air, heats it up to "not quite as hot" then, instead of throwing it out, just drops its temperaure slightly, so the water condensates out, and then heats up the same air a bit more again, so it can load up with more water.

So it only heats air from cold in the first 90 seconds of you turning on the machine. Beyond that its heating warm air to a little bit warmer. And, yes, it does it for way way longer, but STILL uses fewer kWh total.

 

[DAPPH]

I use a washing line, it costs nowt.

Get your friendly BT lines man on side and ask them for some old useable drop wire & a pair of pigtails to p[u it up tightly . Drop wire 10 used to make a fantastic clothes line once you'd used a hot dishcloth soaked in some diluted dishdrops to clean the crud off it after several years of being in the sky .

 

[DAPPH]

If you want to save 100% of the energy that a conventional tumble dryer uses, at a capital cost of around 1% of the cost of the tumble dryer, there’s a fantastic device available called a washing line. No maintenance costs, lasts for around 20 years, only requires some clothes pegs, doesn’t need fluff and condensate emptying and no risk of fire.

Not much cop when its coming down in stair rods & bouncing six feet up at 45 degrees from the ground .