Which is more efficient?

Geo NR Gee · 10-10-11, 11:28 PM

Electric dryer or 12 x 12 room with a dehumidifier and a portable clothes line?

Piwoslaw · 10-11-11, 12:00 AM

Quote:

Originally Posted by Geo NR Gee

Electric dryer or 12 x 12 room with a dehumidifier and a portable clothes line?

Is it possible for you to test both, with a Kill-a-Watt for example?

Geo NR Gee · 10-11-11, 12:47 AM

Quote:

Originally Posted by Piwoslaw

Is it possible for you to test both, with a Kill-a-Watt for example?

I don't know if a Kill-A-Watt unit would plug into the dryer?

strider3700 · 10-11-11, 12:53 AM

it won't. You'll need a much more expensive tool to measure 220V wattage. It's possible to get a rough ballpark average of what dryers will use though using the energystar ratings. Mine for instance uses 2.257 kwh/load based on the energystar label. How close that is to reality I have no idea

S-F · 10-11-11, 06:39 AM

Alternatives to Clothes Dryers | GreenBuildingAdvisor.com

This is an interesting article on just this topic.

Ryland · 10-11-11, 07:23 AM

In order for my dehumidifier to draw 2.2kwh it would have to run for about 4 hours in a humid room, of course as the cloths get drier and drier it will run less and 4 hours to dry seems pretty reasonable.
In the summer you can hang them outside or open windows and maybe just use a fan, in the winter you want to keep the heat inside and driers tend to pump the heat outside, even if you dump it inside with a lint filter on the duct you still have humid air being pumped in to the house causing moisture problems.

S-F · 10-11-11, 07:43 AM

Quote:

Originally Posted by Ryland

even if you dump it inside with a lint filter on the duct you still have humid air being pumped in to the house causing moisture problems.

I have thought a lot about this as the pantyhose tied on the end of a dryer hose is a ridiculous no no but heating the great outdoors slays me. It might not be cost effective but what about an HRV at the end of the dryer hose with extra lint filters?

Piwoslaw · 10-11-11, 08:06 AM

To recapture the dryer's heat, but not moisture, you can try a heat exchanger on the outgoing pipe. Here is a thread on that:
Clothes dryer heat recovery system

Most washing machines on the European market spin at up to 1200-1500rpm, which leaves the wash barely damp, not wet, thereby reducing the dry time and the amount of moisture which has to be dealt with.

Back to the OP's question: I'd guess that the dehumidifier would be slightly better if you have it on anyway. You get some extra heat from it during the winter, while the dryer would pull that heat out of the house. So, during the heating season, the dryer is less efficient on a global (household) scale.

Daox · 10-11-11, 08:14 AM

The problem with the heat recovery is always the lint. If there were a way to seperate the lint from the hot humid air you could then suck the heat out of the exhaust air and just drain the condensate if need be. Perhaps some sort of centrifugal seperator that is easily cleaned?

creeky · 10-11-11, 09:43 AM

I'm not sure in my experience is relevant. But we heated our last house with a pellet stove in the basement and relied on one ducted fan and convection currents to heat the main levels of the house. Worked like a charm.

In the winter my wife hung laundry in the "pellet stove" room and we experienced no mold or excessive dampness issues. The humidity just made the air coming into the house more comfortable.

That said, we were two people, so not a huge amount of laundry. And we had a fairly good washer which spun the clothes pretty dry. (though not as dry as the newer front load models.)

In the summer, of course, we used the outdoor laundry line. And my wife did run the towels in the dryer for 5-10 minutes in order to get them to dry "soft."

10-10-11, 11:28 PM	#1
Geo NR Gee Journeyman EcoRenovator Join Date: Jan 2011 Location: Seattle Posts: 326 Thanks: 109 Thanked 23 Times in 18 Posts	Which is more efficient? Electric dryer or 12 x 12 room with a dehumidifier and a portable clothes line? Attached Thumbnails

10-11-11, 08:06 AM	#8
Piwoslaw Super Moderator Join Date: May 2009 Location: Warsaw, Poland Posts: 961 Thanks: 188 Thanked 110 Times in 86 Posts	To recapture the dryer's heat, but not moisture, you can try a heat exchanger on the outgoing pipe. Here is a thread on that: Clothes dryer heat recovery system Most washing machines on the European market spin at up to 1200-1500rpm, which leaves the wash barely damp, not wet, thereby reducing the dry time and the amount of moisture which has to be dealt with. Back to the OP's question: I'd guess that the dehumidifier would be slightly better if you have it on anyway. You get some extra heat from it during the winter, while the dryer would pull that heat out of the house. So, during the heating season, the dryer is less efficient on a global (household) scale. __________________ Ecorenovation - the bottomless piggy bank that tries to tame the energy hog.

10-11-11, 08:14 AM	#9
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	The problem with the heat recovery is always the lint. If there were a way to seperate the lint from the hot humid air you could then suck the heat out of the exhaust air and just drain the condensate if need be. Perhaps some sort of centrifugal seperator that is easily cleaned? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

10-11-11, 12:53 AM	#4
strider3700 Master EcoRenovator Join Date: Dec 2008 Location: Vancouver Island BC Posts: 745 Thanks: 23 Thanked 37 Times in 30 Posts	it won't. You'll need a much more expensive tool to measure 220V wattage. It's possible to get a rough ballpark average of what dryers will use though using the energystar ratings. Mine for instance uses 2.257 kwh/load based on the energystar label. How close that is to reality I have no idea

10-11-11, 06:39 AM	#5
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	Alternatives to Clothes Dryers \| GreenBuildingAdvisor.com This is an interesting article on just this topic.

10-11-11, 07:23 AM	#6
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	In order for my dehumidifier to draw 2.2kwh it would have to run for about 4 hours in a humid room, of course as the cloths get drier and drier it will run less and 4 hours to dry seems pretty reasonable. In the summer you can hang them outside or open windows and maybe just use a fan, in the winter you want to keep the heat inside and driers tend to pump the heat outside, even if you dump it inside with a lint filter on the duct you still have humid air being pumped in to the house causing moisture problems.

10-11-11, 09:43 AM	#10
creeky Journeyman EcoRenovator Join Date: Jun 2011 Location: a field somewhere Posts: 304 Thanks: 64 Thanked 44 Times in 31 Posts	I'm not sure in my experience is relevant. But we heated our last house with a pellet stove in the basement and relied on one ducted fan and convection currents to heat the main levels of the house. Worked like a charm. In the winter my wife hung laundry in the "pellet stove" room and we experienced no mold or excessive dampness issues. The humidity just made the air coming into the house more comfortable. That said, we were two people, so not a huge amount of laundry. And we had a fairly good washer which spun the clothes pretty dry. (though not as dry as the newer front load models.) In the summer, of course, we used the outdoor laundry line. And my wife did run the towels in the dryer for 5-10 minutes in order to get them to dry "soft."