Thermol 81
Trash or Treasure?
Ed McAllen put me in touch with a women who was looking for a home for some rather unique solar heating tubes. She didn’t want to just pitch them, so I decided that maybe I could use them somehow. If not for the house, maybe for a greenhouse or something. It took a lot of digging, but I did find out some information about them. Each tube is 6′ long and 3″ in diameter and weigh 30 pounds. (I actually found an ad for the “Thermol 81 Energy Rod” in the July/August 1982 edition of Mother Earth News) The tubes are sealed and filled with calcium chloride hexahydrate.
There’s no radiation symbol on the label, so it appears that this is not a plutonium rod.
They have the ability to change from a crystalline state to a liquid state at about 81 degrees Fahrenheit. This process is called a phase change. Phase change materials (PCM’s) are capable of storing large quantities of heat. PCM’s can store many times more heat than sand and even more than water. (I actually found a web site devoted to PCM’s –You can find out everything you ever wanted to know about PCM’s right here.) These tubes were once embedded in a trombe wall in the basement of a condominium. I was able to obtain 48 of these tubes for sweat equity, so what the heck? (If you’ve got any good ideas for using these things or know about how well they actually work or not, drop me a line.) The question is are they trash or treasure?
Has Anyone Seen Our Road?
The last I saw of it, it was heading towards the Root River. Rain is a good thing, just not all at once. With the quick thawing of the snow pack and heavy rains to boot, our road has suffered quite a bit. ( But, I guess I shouldn’t complain. The Root River was flooding again and it appears the Mississippi River will crest at its second highest level at La Crosse next week. Plans are to evacuate a 20 to 30 square block area of La Crosse.)
When I arrived last Monday, parts of the road had been washed out and replaced with deep gullies that took out quite a bit of earth. There were many tree roots exposed where the road once was. I was amazed at how much gravel got washed out since I last visited two weeks ago. I was able to repair the road using the tractor with an 8′ foot blade on the back, but it only lasted a day before the next heavy rains washed out my repair job. Right now there are weight restrictions on the county road, so I’ll just have to wait a bit to get some more gravel. Let’s just hope the gravel arrives before “all hill breaks loose.”
The weather actually cooperated for one day by providing a heavy overcast with no rain. This gave me an opportunity to repair the solar heating system. Over the winter months, the pressure relief valve developed a slow leak and when I arrived two weeks ago, the system was still running, but I could hear air bubbles in the system. So I drained the system and replaced the valve. Luckily, (I think) most of the fluid that leaked out ended up in the 5 gallon bucket that I had placed beneath the pressure relief valve. Tuesday I was able to test the system and everything seems to be running fine. (Keep your fingers crossed.) My thoughts are to keep the system running all summer. This should get the sand bed nice and toasty for next winter.
The proud new owner of a bunch of Thermol 81 Energy Rods. (Please do not send any jokes about this.)
What’s Next ?
Depending upon the weather, I hope to install the lightning protection system for the house and do a few repairs on the Bobcat over the next week or so. After that it’s cordwood wall construction time. (Probably starting in May.)