Morus Zero - Ultra-fast countertop tumble dryer for any home

[PlainName]

Most people know, that water boils at lower temperature at lower pressure.
Most people dont know, how this really works, and what is the temperature and what pressure.

This. We learn as kids that tea made at the top of Everest is really weak, and we've seen the videos of stuff boiling off at low temperatures. It's pretty much like proving we went to the moon when world+dog could see the flag waving - on an airless world - in the original video.

But them's the breaks. Debunking isn't about reeling off numbers and having your audience fall asleep (or watch more conspiracy channels). You need to be more convincing than what you're debunking, and it's that a bit too difficult then you should stick with your day job. A bad debunking video is counterproductive and merely proves whatever is being debunked is actually real.

[Marco]

And they dont know how difficult it is to make a vacuum chamber.

This isn't high vacuum. The requirements are no different from the multitude of degassing vessels for epoxy.

[EEVblog]

The only problem with thunderf00t's video is that the topic itself is very hard to understand and subsequently very hard to explain and demonstrate in what appears to be a rushed video.

I don't have nearly enough physics knowledge to verify TF's view on this, but I've found he's always right on the fundamentals even if he (like everyone) occasionally goofs a calculation or something.
There are some people saying TF has the physics wrong here, but AFAIK no one has close to the credentials in the field that TF has. So I'd be very surprised if he's wrong.
It's kinda like the the equivalent of the Walter Lewin "Disagreeing with the master" thread on Kichoff's Law

[thm_w]

I don't think you want a microwave arcing with the inevitable belt buckles.

Not to mention a lot of reflective clothing seems to have metallic elements in them. I thought it was just glass beads, but no, its more than that (as I tragically found out last week):

"Many Scotchlite reflective materials contain an aluminum layer as part of their construction."
https://multimedia.3m.com/mws/media/824071O/reflective-consumer-products-data-sheet.pdf
https://www.3m.com/3M/en_US/scotchlite-reflective-material-us/industries-active-lifestyle/active-lifestyle/

You might sense something as large as a buckle, but things like snaps, pins, reflective, is going to be way too small to detect and could destroy an entire load of laundry.

He is cherrypicking data to suit his debunking agenda. Example: in particular video he first explains how much energy needed to evaporate 1Kg of water which is roughly 2000000 J. Then he conveniently takes same 1Kg to prove that 900W device cannot evaporate such amount of water in 15 minutes, 2KW power needed instead. Seemingly job is done, lies of manufacturer debunked, right? Well... specification says max load = 1.5Kg. In specification there's no mention 1L or 1Kg of water, just BS assumption of 10-30% water contents after spin drying. Anyway if 1.5Kg of damp clothes contains 1Kg of water then it is dripping wet sponge, not clothes out of the modern >= 1200 RPM spinner.

So residual moisture content appears to be 40-50% depending on the quality of the spin cycle and materials washed. Towels will be worse, but I assume this thing is not used to dry towels.
If the max load is 1.5kg, then we should be talking about removal of 600-750g of water.

https://www.coolblue.nl/en/advice/washing-machine-rpm.html
https://bandctech.com/commercial-laundry-blog/2017/02/understanding-moisture-retention-in-your-commercial-laundry/

This should be close to 2MJ at 25C right (250k to raise temp and 1,690k to turn to steam)? Assuming normal pressure and 0.75kg.
Next, I'm thinking if you completely removed the temperature rise, you'd still be left with 1,690kJ, not too far off from his number. Is there any way to get better than that?

https://www.quora.com/What-is-the-energy-needed-to-evaporate-1-kg-of-water

[ogden]

So residual moisture content appears to be 40-50% depending on the quality of the spin cycle and materials washed.

Right. Yet they say it's 10-30%. They also use pounds in energy efficiency number, 0.24kwh/lb while capacity of dryer is specified in kg   Clear indication that they are not completely honest about numbers. Note that 0.24kwh/lb = 0.53kwh/kg, most heat pump dryers are 0.3-0.4 kwh/kg efficient.

If the max load is 1.5kg, then we should be talking about removal of 600-750g of water.

Yes. To dry 750g of water, it takes 60*0.75*0.53 = 24 minutes, 30 min considering losses. Not 15 as they claim

BTW just checked that internal energy of 1kg saturated vapor at 101 kPa (standard atmospheric pressure) is 2.5 MJ but at 6% of atmospheric pressure (vacuum of Morus Zero) it's 2.4 MJ. Saved energy due to vacuum - miserable 4%. T-foot is right saying that vacuum is gimmick. Conclusion: save little more money and get proper heat pump tumble dryer.

[ebastler]

So residual moisture content appears to be 40-50% depending on the quality of the spin cycle and materials washed. Towels will be worse, but I assume this thing is not used to dry towels. If the max load is 1.5kg, then we should be talking about removal of 600-750g of water.

https://bandctech.com/commercial-laundry-blog/2017/02/understanding-moisture-retention-in-your-commercial-laundry/

I don't think you got the numbers quite right. As stated on the page you linked to,

how much water is left in the goods after extract [is] expressed as a percentage of the original dry weight prior to washing

So for a 1.5kg load with 50% residual humidity, the dry weight of the laundry would be 1kg and the water content 500g.

Hence, if we neglect losses, the stated 15 min drying time seems not too far off. If we assume a more favorable 40% residual humidity as the starting point, there is even room for some losses.

[ogden]

So residual moisture content appears to be 40-50% depending on the quality of the spin cycle and materials washed. Towels will be worse, but I assume this thing is not used to dry towels. If the max load is 1.5kg, then we should be talking about removal of 600-750g of water.

https://bandctech.com/commercial-laundry-blog/2017/02/understanding-moisture-retention-in-your-commercial-laundry/

I don't think you got the numbers quite right. As stated on the page you linked to,

Seems to be right. Consumer washing machine *and* dryer capacity usually is specified as dry laundry weight *before* washing.

[ebastler]

Seems to be right. Consumer washing machine *and* dryer capacity usually is specified as dry laundry weight *before* washing.

Ah, thanks -- that had not occurred to me. Makes sense for washing machines, of course, but is a bit counter-intuitive for dryers. But you are right, that seems to be the consensus for specifying capacity. So the Morus spec is indeed highly optimistic, by assuming unrealistically low moisture of the incoming laundry.

[PlainName]

I am dubious that there is 40-50% water content after spin drying. When I hang  up stuff it is not much heavier than dry, and MUCH lighter than not spun. But my google-fu is lacking and I can't find a source of figures, not even made up ones!

[thm_w]

I am dubious that there is 40-50% water content after spin drying. When I hang  up stuff it is not much heavier than dry, and MUCH lighter than not spun. But my google-fu is lacking and I can't find a source of figures, not even made up ones!

I had two links in my post for references. But, that is a good self experiment to do: measure weight before washing, after washing and spin cycle, then after drying and let us know.

Might find more in here:
https://link.springer.com/article/10.1007/s11743-005-0335-5
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1470-6431.2010.00975.x
https://link.springer.com/article/10.1007/s12053-014-9268-4
http://wiki.zero-emissions.at/index.php?title=Drying_of_clothes

I think its hard to tell a 40% increase in weight when the item is so light to begin with. Towels/cotton is the worst, "quick dry" style sports fabrics could be better than 40%.
But generally in a load of laundry you will have a mix of these items, so the average would still be in that 40-50% range.

[PlainName]

I will check when we next do the laundry, but we don't have a drier other than fresh wind.

[KaneTW]

Vacuum drying is actually pretty efficient, since heat isn't wasted for heating up the clothes material or the dryer significantly above ambient. It's just that you still need to supply heat or pull a progressively stronger vacuum. Microwave-vacuum drying is getting popular, where microwaves are used to heat up the water (and avoiding the vacuum heat transfer issue).

If one kg of water evaporates, it removes 2.2MJ from the system. You still need to add those 2.2MJ to the system, but since it's running close to ambient, heat losses are going to be much smaller. Don't forget that the heat transfer rate is Q' is proportional to DeltaT. This eliminates the major contributor to energy losses --- heat leaving the system to ambient.

[ogden]

Vacuum drying is actually pretty efficient, since heat isn't wasted for heating up the clothes material or the dryer significantly above ambient. It's just that you still need to supply heat or pull a progressively stronger vacuum.

Exactly - heat *and* vacuum supply needed because of evaporation. Vacuum pump needs energy and has it's own (in)efficiency figure. Whatever is efficiency numbers of other vacuum dryers, Morus is not in "pretty efficient" category. It does not beat efficiency numbers of common heat pump dryers (0.53 versus 0.3-0.4 kwh/kg). Numbers from document T-f00t used in his video.

[PlainName]

It does not beat efficiency numbers of common heat pump dryers

I don't think they claim that it does. What they do claim is that it's quicker than conventional (which I presume means non-heat pump) dryers, and it does it on a counter top.

[ogden]

It does not beat efficiency numbers of common heat pump dryers

I don't think they claim that it does.

They do, by claiming 40% energy savings

[PlainName]

A I point out, they make the claim against conventional dryers. All they need to do is find one that gives 0.4kwh/lb and they're quids in.

But they don't even need to do that, because they claim up to 40%, so it's basically claiming whatever they want it to

[ogden]

A I point out, they make the claim against conventional dryers. All they need to do is find one that gives 0.4kwh/lb and they're quids in.

But they don't even need to do that, because they claim up to 40%, so it's basically claiming whatever they want it to

It's marketing by deception. Anyway you can twist it as you like, fact stays: Morus Zero is not as efficient as modern tumble dryers. Last time I repeat this.

[paulca]

The only problem with thunderf00t's video is that the topic itself is very hard to understand and subsequently very hard to explain and demonstrate in what appears to be a rushed video.

I don't have nearly enough physics knowledge to verify TF's view on this, but I've found he's always right on the fundamentals even if he (like everyone) occasionally goofs a calculation or something.
There are some people saying TF has the physics wrong here, but AFAIK no one has close to the credentials in the field that TF has. So I'd be very surprised if he's wrong.
It's kinda like the the equivalent of the Walter Lewin "Disagreeing with the master" thread on Kichoff's Law

He put up a video recently, which while a little egotistical, was enlightening as to just how experienced he is.  More importantly how published and how widely cited he is in academic journals.  Basically he is a very widely published and cited experimental physicist.  Of course day job experience doesn't always translate directly to hobby videos, but like I trust (you) Dave in electronics, I kinda tend to trust TF in his experimental physics, while some of his hyperbolic assumptions can bring a frown or two to my face.

I have watched a lot of his videos and you will find a few where he admits to errors in calculations or in assumptions.  The NASA Mars helicopter debunking for example which he mostly retracts.

[KaneTW]

Vacuum drying is actually pretty efficient, since heat isn't wasted for heating up the clothes material or the dryer significantly above ambient. It's just that you still need to supply heat or pull a progressively stronger vacuum.

Exactly - heat *and* vacuum supply needed because of evaporation. Vacuum pump needs energy and has it's own (in)efficiency figure. Whatever is efficiency numbers of other vacuum dryers, Morus is not in "pretty efficient" category. It does not beat efficiency numbers of common heat pump dryers (0.53 versus 0.3-0.4 kwh/kg). Numbers from document T-f00t used in his video.

It doesn't, not even remotely. That's why I'm so upset about it---you can make an innovative product, but instead they just produce some dumb-ass garbage.

Not to mention that a well engineered vacuum drying solution will be way more expensive. Their shitty product will fail in a year simply due to water damage to the shitty cheap pump they're using.

[Sonny_Jim]

They just tried to astroturf their 'rebuttal' video on /r/shittykickstarters:

[PlainName]

Well, you certainly did that for them here 

[Sonny_Jim]

*shrugs*

They have a right to respond to criticism, but we have rules over there that they have to do it as themselves, not brand new sockpuppet accounts with nothing posted apart from that video.

https://np.reddit.com/user/coconutkunka

[ogden]

At least they did not lie by stating "Morus Zero is more efficient than [ancient] vented tumble dryers"

FYI most washing machines specify 50..53% RMC (Remaining Moisture Contents) for full load, cotton, 1400rpm spin, including Miele (link to pdf user manual). Morus Zero team probably tested just barely loading washing machine with few synthetic T-shirts - that's why 33% figure.

[Marco]

I wonder about the energy limits of a dryer, if you exhaust water vapour with the vacuum pump you obviously lose all the heat of evaporation. A mostly closed cycle which recondenses the water and recovers the energy might be possible though.

Just breaking the molecular bonds between the fabric and the water takes I think far less energy than the evaporation.

[thm_w]

I wonder about the energy limits of a dryer, if you exhaust water vapour with the vacuum pump you obviously lose all the heat of evaporation. A mostly closed cycle which recondenses the water and recovers the energy might be possible though.

Just breaking the molecular bonds between the fabric and the water takes I think far less energy than the evaporation.

Potentially a re-usable dessicant could help with this process, but you'd need some post drying cycle.
Ultrasonic to break the bond maybe: https://insiderlouisville.com/economy/ge-appliances-wants-to-vaporize-the-water-in-your-laundry/