Drying clothes indoors...

[Externet]

Hi.

In some other forum, a beginner asked how to run a domestic clothes dryer from batteries to save in electrical power , and responses were of course, to discourage such by multiple solid reasons.

 

I suggested as alternative to make a 'closet' with the clothes hanging and force fan-air flow, no heat added. It would take much longer time, but...

 

Would that electric fanning take much less energy for a much longer time ending in a not-worth-it alternative than a several kilowatts for only a couple of hours domestic clothes dryer ?

 

In other words, would indoor clothes drying need to use the same amount of energy no matter what the method ? I do not think so, but would like comments.

The extreme is just leaving clothes hanging for a week? indoors, they will dry anyway for $0

[Bob_for_short]

I suggested as alternative to make a 'closet' with the clothes hanging and force fan-air flow, no heat added. It would take much longer time, but...

 

A little wind without closet will do.

[Mr Skeptic]

All you have to do is allow for diffusion of the water vapor off the clothes. They will dry fine out in the open. Warmth will increase the vapor pressure, airflow will decrease the nearby humidity (faster diffusion if you prefer), both of which will improve drying speed.

[swansont]

The dryer is a device to save time and space, at the cost of energy and hardware. A fan would cost a few Watt-hours, but I would not be surprised if it was 100x less energy what it took to run a dryer.

[lemur]

relative humidity makes a big difference when hang-drying clothes inside or out. Hang-drying clothes indoors in the winter when the air is dry from heating is ideal because not only do the clothes dry faster but they also humidify the air a bit. Outdoor drying is ideal when the sun is shining but when it's overcast and humid, they can take a long time and smell. Dryers are nice when its humid and overcast.

[CaptainPanic]

You should realize the following:

 

The evaporation of water costs 2.26 MJ/kg, regardless whether this happens in a tumble dryer, in a closet with a fan or anywhere else.

So, if you have plenty of heat in your house (warm climate, or because it's summertime) then the 2.26 MJ/kg of heat required are available for free. But if it's winter, then your heating system will provide the energy for the evaporation of the water... the water will evaporate, and the air and clothes cool down because of it.

 

So, it's probably not the fans that need attention, it's the heating.

Even large fans require about (max.) 50 W. I have computer fans of as little as 5 W, and a big fan for cooling in the summer of 35 W at home. A quick search online told me that tumble dryers can use as much as 2500 W (!).

Edited September 13, 2010 by CaptainPanic

[dalemiller]

Something yet worth mentioning is that a typical clothes dryer arrangement blows heat and moisture out of the building: all good riddance in the summer time but subject to some limited conservation in cold weather. Decades ago in the North Country, clothes dried outdoors under freezing temperatures brought new meaning to "clean and fresh". Down in the South Country, who needs clothes?

[John Cuthber]

If you dry clothes outside then you don't need to care where the 2.26MJ/Kg comes from. It's possible (if a bit slow) to dry clothes outside even when the temperature is below freezing.