Solar Powered Clothes Tumble Dryer

[Leta]

I have been thinking hard about this. I have thought about having a room just for the indoor drying of clothes, but that seems neither cost effective nor green. In my climate, there is simply no way to line dry outdoors all year round. At minimum, you would need some sort of porch, but still, that would consume a lot more space than than a 5 cu ft tumble dryer.

So what I've come up with doing something like this:

http://www.instructables.com/id/Summer-Energy-Savings-by-Modifying-Your-Electric-C/

But instead of having the hot air come from your attic, or, as freemotion mentioned, a woodstove, have the ductwork hooked up to a homebuilt version of this:

http://www.cansolair.com/

(DIY solar heating panel videos abound on YouTube.)

It would mean orienting your dryer so that it was along the south side of your house (assuming we are all in N hemisphere, sorry to those down under!), or having really long ductwork trails. The other advantage to just having your dryer right there on the S side would be that you could also hook up a solar panel to the 110 plug that spins the dryer. Yeah, you'd have to buy a small inverter, but those have gotten CHEAP, we have one that we bought for $25. You'd also need a few deep cell batteries, which would almost certainly be the most expensive part of this.

If you got, for example, a gas dryer that had bad seals, you could scrounge that for free. You'd have to invest a few hundred dollars in the solar heating panel, and, if desired, the solar electric panel/inverter/batteries, but considering that a new dryer costs about $300, this would be cost effective up front, free in the long term, and would not take up nearly as much space as an indoor drying room or cost even a fraction of what a drying porch would cost.

 

[Leta]

My only real question is how big of a solar panel I'd need. The Cansolair model is just under 4'x8', and they say you can heat 1000 square feet with it, so I'd imagine you could get away with 4'x4' or even 2'x4' version.

 

[Marianne]

IMO, I think you'd still need the bigger solar unit or you wouldn't get enough warmed air. I did a quick google search to see how much air the average dryer pumps and got nothing... but I know it's significant. I have an electric dryer that is vented into the house during the winter and there's a lot of air coming out of the vent. If all that air is being pulled through the solar unit, I doubt that it'd have enough time to actually warm up much after a few minutes of use.

I have seen both those links before, pretty interesting, huh. But when they say that the solar unit will heat 1000 sq.ft., I don't believe them. It might heat that much space by the end of the day, but...

Kind of like my wood burning stove that advertises it will heat for 6 hours. After that time, it's cooled enough that I can lay my hand on it (but still barely warm) and the temp in the room has already dropped 10 degrees on a really cold day.

I've never seen a full size dryer that runs on 110. That's probably all you need to actually spin the drum, but aren't they all wired for 220? (Manufacturers assuming that you'll use the heated cycles.)

I too, have indoor lines that I have to use. I have farm fields on either side of me and with the wind, there's too much grain dust, dirt, etc that's blowing constantly. But I like the convenience of using a clothes dryer and it'd be nice to use it guilt free. :/

 

[Leta]

We have a gas dryer, and it runs on 110. It's just a regular plug, as a matter of fact, it's plugged into a bog standard power strip.

We used to have an electric dryer with the vent diverted into the basement. (In this same house. We got the gas hookup installed when we realized that, even with 80% line drying, at .20c per kWh, our electric dryer was costing us $100 per month. To dry 3-4 loads per week!) Anyway, the little "Extra Heat" vent diverter did not warm our 600 square foot basement. (It's actually 700 square feet, but part of it has been partitioned off into a root cellar/pantry.) It didn't even come close. And our basement tends to stay much warmer than the rest of our house in the winter, I've never seen it below freezing.

Our electric dryer was purchased new in 2009, and was working fine when we sold it.

Something that I learned when I worked at a laundry was that commercial electric dryers are relatively rare, both because they are much less efficient than gas dryers, but also because gas dryers just get hotter faster and turn customers around much more quickly. Imagine the difference between a gas and electric stove, for example. According to the gentleman who installed our dryer hookup, our gas bill would go up only a marginal amount because the air inside the dryer is not constantly heated- there is a burst of new, hot air at startup, and, on newer dryers, every 20 minutes or so, and that's it. The majority of the energy that's used in a gas dryer is electricity to keep the drum turning. He was right. The month after we got the gas dryer, our electric bill went from $156 to $56, and our gas bill went from $40 to $42.

I'm not sure how well the solar heating panels work (though they are getting more popular where I live, N of 45) but my theory was that if a gas dryer can dry clothes with small spurts of hot air, the lower temp but continuous hot air coming from the heating panel would do a similar job. This is, mind you, all theory, though if this weather ever gets its act together we are going to build a couple of solar heaters before the fall...

 

[Marianne]

Holy Mama! And here I grumble because we are paying around $0.12 per KWH.

That's pretty interesting. It's been years and years since I've had a gas dryer. Natural gas isn't available where we currently live, propane was sky high at the time we were building, so we're all electric. I was the driving force on that decision, figuring that one day we'd get solar panels, etc.

I'm still shocked that your electric dryer cost that much to run. I average a load about every other day. The most I have seen our ele bill drop was $20 a month when I was hanging every load.

Here's a link to Mr. Electricity's dryer page - http://michaelbluejay.com/electricity/dryers.html . Love that guy's site! It's easy to plug in your own ele costs, etc to get a more accurate figure on how much all kinds of ele things are costing you. He also states on his home page that appliances vary wildly and I believe him.

Overall, I'm a big fan of passive solar. That's where you get the biggest bang for your buck as so many things can be scrounged or are readily available. I was going to do the can-type heater too. The http://builditsolar.com website did some tests on different collectors. I was surprised that the screen collector won. Sure would be simplier to make. The can collector was not in this experiment - I wonder how it would have stood up...

http://builditsolar.com/Experimental/AirColTesting/Index.htm

I like your thoughts about designing the laundry room to be on the sunny side of the house. Sure would make it easier.

 

[~gd]

I have been bopping around on the net today and was looking up the average electrical usage of appliances. The biggest user in my house is the hot water tank. I will be doing a cost analysis on the switch to see if it is worth it in the grand scheme of things around here.

One of the other big users especially for us is the clothes dryer. With 4 kids living at home, the washer and dryer seem to be going all the time. With a clothes dryer using as much as 5000 watts of electricity per hour and a dryer working for 3-4 hours per day 5 days a week, there seems to be a place where energy could be saved.

Clothes lines are the obvious, but in wet and colder climates, this is not much of an option most of the year. I decided to look at the problem and I think I have come up with a cool idea that could theoretically save a lot of energy for the average household.

I believe that if a solar collector was built on the side of a house on a south facing wall. The collector would have to be 8' tall at least 6' wide and approximately 3 1/2' deep. The idea would be to take an old nonfunctioning clothes dryer and scavenge the parts needed. Heck even a good used working one only costs $75. Inside the heat collector, you would remount the drum and rotating motor with belt. Then using the door, you could mount the door on the interior of the house wall. Basically you are using the heat collector to replace the heating elements of the dryer. I think it would be a good idea to pour a concrete floor with a drain in the bottom of the collector so that draining water from the drum has a place to go. A three foot splash guard from the floor up would be a good idea too. The electric motor used to turn the drum only takes about 450-500 watts to turn the drum, so theoretically you could be saving as much as 4500 watts of electricity per hour and in our house that could mean as much as 1kw a weak.

Your math/definations are weak 4500wattts/hour =4.5kw/h so 1 hour of running would = 4.5 kw. Why the floor drain? if your clothes are dripping water there is something wrong with your washer spin cycle. What about ventilation? damp clothes + heat =hot damp air and that doesn't dry well. I could be wrong I haven't read the thread yet, but I think it is back to the drawing board for you. ~gd

 

[~gd]

Where I live, hanging clothes out to dry is an invitation to cloth the residents of the next state!

If you see some size 16 tall jeans blowing by, those are mine

(I have had to retrieve clothes, patio umbrellas and lawn chair cushions from the neighbors on more than one occasion )

Aha so the ladies underwear I have been finding in my back yard is blowing in from Colorado? I thought it was probably coming from the lovers lane right behind my back fence. Why is it always women's? because men's jocky shorts don't make it over the Smoky Mts but silky nylon soars? ~gd LOL

 

[Marianne]

 

[Leta]

Yeah, the way our electric bill is broken down is purposefully obtuse. If you call them and ask, they'll tell you it's 12c/kwh, but if you actually break down all the individual "per unit" costs, it works out to 20c. Aaaand they are talking about raising it up by 7.7% this year, after a 20% increase last year. I don't know what the moderation here thinks of profanity, so I will refrain from saying what I really think of our electric company.

The crazy part is that entire U.P. is a patchwork of various electric companies, and they often overlap. 15 miles away, the community owned electric company has rates of 8c/kwh. U.S. average is 11.5. So we have 200% of average right next to 75% of average. It's nuts, but I don't know what to do to fix it, other than get off the grid.

I love Mr. Electricity, too! His site was very helpful when we were improving the energy use of our home.

Marianne, YOU were shocked after you found out how much that d--n dryer was costing us, you should have seen our faces! My jaw dropped when I opened our August 2010 electric bill. I mean, shocked in a good way, then sickened by how much money we had wasted in the previous four years...

 

[sunsaver]

A clothes line in the sun, a clothes line on the porch for rainy days, a clothes line above the wood burning stove for freezing weather. Electric bill? Zero! I'll never go back on the grid! Those electric companies are evil! "Here's a good way to save energy! Oh, but we're going to raise your rates, so you'll still be paying more. Hope you enjoy working harder to pay us more!"