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Ultra-low-energy consumption ultrasonic clothes dryer

energy.gov

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Re: Ultra-low-energy consumption ultrasonic clothes dryer

#181

Post by awqrre »

Arizhel wrote: post #179
awqrre wrote: post #177

Earlier quoted context omitted.

Who cares about delivery fees? it's the total cost that matters.

The delivery fee is a significant fraction of the total cost of a modern dryer in the US. Saving a little money by getting crappier dryers will likely have a larger total cost because of the delivery fees, and also the cost of your time in taking time off from work to accept delivery.

that dryer costing $180 at Home Depot has free shipping, by the way... http://www.homedepot.com/p/Magic-Chef-Compact-1-5-cu-ft-Elec... .... and by the way, you are paying for shipping even if you by at the store (it is just included)

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#182

Post by DKnoll »

nickpeterson wrote: post #172
DKnoll wrote: post #158

Earlier quoted context omitted.

First you need engineers that can design appliances that, even if warrantied, do not need service within 25 years 100% of the time. Perhaps they can be legislated into existence... ;)

There is a rover on Mars that had been running by itself for quite a bit and it contends with far more than a dryer.

I assume you don't mean Beagle 2.

A Mars rover is a bad example here because it's not an item that is, or will ever be, mass-produced.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#183

Post by Arizhel »

awqrre wrote: post #181
Arizhel wrote: post #179

Earlier quoted context omitted.

The delivery fee is a significant fraction of the total cost of a modern dryer in the US. Saving a little money by getting crappier dryers will likely have a larger total cost because of the delivery fees, and also the cost of your time in taking time off from work to accept delivery.

that dryer costing $180 at Home Depot has free shipping, by the way... http://www.homedepot.com/p/Magic-Chef-Compact-1-5-cu-ft-Elec... .... and by the way, you are paying for shipping even if you by at the store (it is just included)

WTF? We're talking about real dryers here, not dorm-sized dryers that you can dry maybe 2 shirts in.

However, if you select the Samsung 7.5cf dryer, it also has free delivery. Of course, this is built into the price, and $550 for an appliance isn't pocket change.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#184

Post by uncensored »

db48x wrote: post #100
uncensored wrote: post #96

Earlier quoted context omitted.

"denaturing" does sound scary and bad -- It's a dumb way to describe what happens in any cooking process.... it sounds like turning food into plastic before eating it (take the nature our of it) LOL. Anyway, there are real health risks according to the World Health Organization: "Food safety: Food safety is an important health issue. In a microwave oven, the rate of heating depends on the power rating of the oven and…

That's why your microwave oven has a power setting. It toggles the magnetron on and off during cooking, so that your food cooks more evenly.

Yet it never does, unless maybe you have a $2000 microwave oven?

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#185

Post by kurthr »

kortex wrote: post #138
kurthr wrote: post #131

Why not just use a vacuum pump and pull the water vapor out at a constant temperature. You can flow 33C dry air (use a condenser before expanding and heating, if you like) across the clothes as they tumble to keep them from freezing. You wouldn't have to pump below a 10% of an atmosphere to quickly dry your clothes (vapor pressure of water is 5% of an atmosphere at that temp). To give an idea of how fast: With a 1lit…

And with the air mostly removed, you can spin the drum really really fast! I think you're on to something here. :P Maybe not. I've done hundreds of solvent evaporations under vacuum (rotovap). The problem is you need a trap, or else solvents condense in the pump which causes your efficiency to go down. So now you need a heat pump or similar, now you're talking about a really complicated dryer. But it'd be efficient.

Yeah, thanks for the comment on the condensation.

The output pump would really need to mostly pump water and vapor at the input and liquid at the output, but not to very low pressure... even a peristaltic might be doable (no rotary vane/blower needed). It was just a thought, I used to rotovap too so running through the calculations seemed like a fun idea.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#186

Post by chemmail »

nickpeterson wrote: post #147
zkms wrote: post #62

Earlier quoted context omitted.

> The idea sounds pretty neat but I wonder about longevity of the piezeoelectric transducers. If they'll wear out fast it's entirely feasible to design the dryer around user-replaceable piezos. It may end up like with inkjet printers -- where the dryer itself is just a boring spinning drum with a fan and a moisture collector and a powerful piezo driver, and you end up buying consumable cassettes with the actual trans…

You know what I want? A lemon law that states that major appliances need to run forever. Literally something that says, "This device must run without professional service for 25 years." Forget energy star stuff, 100Kwh saved a year is meaningless because we can always optimize powerplants. Stop building disposable 100LB metal boxes that have to get scrapped and thrown in a landfill. If the device fails earlier than t…

Or just buy my grandmas fridge from the 60s that still running strong.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#187

Post by awqrre »

Arizhel wrote: post #183
awqrre wrote: post #181

Earlier quoted context omitted.

that dryer costing $180 at Home Depot has free shipping, by the way... http://www.homedepot.com/p/Magic-Chef-Compact-1-5-cu-ft-Elec... .... and by the way, you are paying for shipping even if you by at the store (it is just included)

WTF? We're talking about real dryers here, not dorm-sized dryers that you can dry maybe 2 shirts in. However, if you select the Samsung 7.5cf dryer, it also has free delivery. Of course, this is built into the price, and $550 for an appliance isn't pocket change.

here is a pocket change dryer that is slightly larger: http://www.homedepot.com/p/Amana-6-5-cu-ft-Electric-Dryer-in... and of course it also has free shipping.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#188

Post by db48x »

uncensored wrote: post #184
db48x wrote: post #100

Earlier quoted context omitted.

That's why your microwave oven has a power setting. It toggles the magnetron on and off during cooking, so that your food cooks more evenly.

Yet it never does, unless maybe you have a $2000 microwave oven?

Yours doesn't toggle on and off when you use the power level controls? Maybe it's broken; this is a feature that all microwaves have, because it's so cheap to implement. Note that the lights and fans and things keep going; it's only the magnetron that turns on and off. You might hear a difference in the sound of the microwave, or a relay clicking when it toggles, but that's all.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#189

Post by sargun »

yetihehe wrote: post #111
sargun wrote: post #101

Earlier quoted context omitted.

I've thought about buying an old 200mm or 230mm fan, and hooking it up to a Peltier cooler -- First pass the air over the "cold" side to drop out the moisture, then through some rechargeable desiccant, and then through the hot side to my clothes. I wonder why dryers don't work this way, other than I think that it'd be much slower to dry as compared to a traditional dryer, and I'm not sure if you'd be able to wick the…

Why rechargeable dessicant when moisture just condenses on cold side? Then it drops into container. Also peltier cooler is too inefficient to do this. It uses about half of energy just for resistive heating. Typical european dryer works just like this but doesn't use dessicant.

Unless you drop the air temperature down to below 0, all the moisture won't drop out on the cold side.

Re: Ultra-low-energy consumption ultrasonic clothes dryer

#190

Post by celticninja »

seanmcdirmid wrote: post #144
celticninja wrote: post #142

Earlier quoted context omitted.

However never hang clothes on a radiator to dry, this is the least efficient method of using your radiators.

If you have city central radiated heating, then making the radiators less effective is just a bonus of getting your clothes to dry a bit faster.

I'm not sure how common that is, the only place I have heard of it is in some Scandinavian countries but if you know otherwise i would love to hear about it.
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