LOUDON, Tenn. — With the cost of utilities weighing heavily on many coin laundry owners across the country, a wide variety of cost-saving products have been developed to cut down on utility usage, as well as recycle energy and water. Usually this equipment comes in the form of heat reclaimers and solar panels, which can be purchased through manufacturers that specialize in these types of products.
Lynn Millsaps, owner of Loudon Speedwash Laundromats in Loudon, Tenn., decided to take a different route to decreasing utility usage. He took the knowledge he had of heating and air conditioning and a little elbow grease and came up with his own method of providing his dryers with preheated intake air.
Things have gone well. HIs greenhouse-like solar collector on the side of his coin laundry constructed mostly from materials from a standard building supply store, has customers talking.
STARTING THE PROCESS
What would prompt someone to take on such an endeavor? In Millsaps’ case, it was pretty straightforward. His 1,600-square-foot store has 20 top-load washers and seven front-load (triple-load) washers, but it was the 12 stack dryers and their natural gas usage that really gave him the idea.
“I was paying $1.10 for 100 cubic feet of natural gas, and within a 26-month period, it doubled to $2.22 or something like that,” he says. “I decided to go ahead and do something about it and try to save some energy costs. The crisis is going back down now, but I’m still saving energy.”
Millsaps used to teach heating, air conditioning and refrigeration back in the 1970s during the energy crisis, and he used that knowledge to come up with the idea for his solar collector.
“I did some experimental solar things back when I was teaching heating and air conditioning, and I just used my knowledge that I already had of that and decided to build a solar collector,” he explains.
THE NUTS AND BOLTS
While many energy-saving devices can be fairly high-tech, Millsaps’ solar collector is actually constructed primarily of everyday building materials and operates using a relatively simple concept.
Basically, he built an ordinary room on the side of the coin laundry with a clear, plastic roof that allows sunlight to pass through. Inside the building are cinder blocks, painted black, on their sides, and inside of the holes in each cinder block is a brick, also painted black. These heat up as sunlight comes in through the roof.
On the laundry side of this room is the intake air opening for the dryers. On the other side is an opening to the outside air.
“The cinder block and brick actually absorb heat when the sun is shining, and they hold the heat until somebody comes along and puts money in the dryer. When the dryer starts, it pulls warm air out of that room into the back of the dryer and pulls the cooler outside air into the other side,” he explains. “So the air has to go in one side and go all the way through the solar collectors to get into the room where my dryers are. By the time it gets from one side to the other side, it heats up.”
The cinder blocks and bricks are arranged in such a way that they take up as much room as possible inside the solar collector room, but still allow air to move from the fresh-air side of the room to the dryer side. In addition, most of the materials were pretty easy to come by, apart from the clear, plastic roof, he says.
“I got all the other material from a standard building supply place, you know, just insulation, two-by-eights, two-by-sixes, and so forth — but the top that I put on is the same material that they use on greenhouses, which is actually a double piece of plastic with a quarter-inch gap — an air pocket.
“It’s real strong, and the air pocket serves as an insulator. I don’t remember exactly what it cost me, but it’s about twice as much as doing it if I were to use a single layer like Plexiglas or something of that nature,” he says. “If you get a single sheet it’s a lot cheaper, but I went ahead and got the double with a quarter-inch air pocket in it because of the insulation factor.”
AFTER THE INSTALLATION
To see if his idea was working, Millsaps decided to simply record the temperature of the air going into the dryers and see if it was any warmer than the outside air.
“I bought a temperature data recorder, and the inside temperature for the month of July averaged about 125 degrees,” he says. “That’s inside air temperature going to my dryers. So, depending on what the temperature was outside, you know, if it was 90, then that means I’ve preheated it up 35 degrees. If it was 95 outside, which we’ve had some 95-degree days in July, that means I’ve heated it up 30 degrees.”
Millsaps’ investment in the solar collector amounts to roughly $8,000. With the water heaters also running on natural gas, and dryer savings being dependent on the time of day that customers use the machines, it’s difficult to calculate the exact savings it’s providing.
“It’s just impossible to tell about that situation, but as long as I’m preheating air 30 degrees, I know I’m saving money,” he says.
Millsaps has discovered that the time of day doesn’t affect it as much as you might think, because even without sun, the bricks hold their heat for a surprisingly long time.
“Even at night, when the sun goes down, the temperature goes down inside, of course, from people using the dryers after dark, and there’s heat loss after dark, but it looks like the low temperature during the month of July probably averaged 85 degrees,” he says. “That means if it got down to 65 outside, I was still 25 degrees warmer inside. I’m increasing the air temperature by 20 degrees even after dark, so it’s 24-hour-a-day savings.
“The inside temperature never gets equal to the outside because I have those cinder blocks and bricks in there holding heat.”
While he doesn’t use the solar collector as a promotion piece, Millsaps says that just having it on the side of his building draws a pretty big customer response.
“I’ve had a lot of comments,” he says. “A lot of customers say it’s a good idea, and they appreciate me doing that and trying to save natural resources and so forth. They say it’s a shame everybody couldn’t do it.
“I’ve had a lot of people come down and ask me about it, and I’ll explain to them how it works. A lot of them are fascinated by how simple it is, and yet it works.”