Posted by CraigNels on December 4, 2003, 4:47 am
I'll be building a new house in two years and am planning for solar now. I've
posted a drawing of what I have in mind at:
This is my own design and I've not seen anything like it, so naturally I fear
I've made some terrible blunders in the design. I would appreciate any
The system is basically an evacuated tube collector with wax heat storage and a
single recirculating pump.
Thanks in advance for your sage advice.
Posted by JWDoyleJr on December 4, 2003, 7:06 am
You've obviously been studying the physical properties tables and found that
many waxes have high specific heats and especially high heat of solidification.
Read on. They also have very poor heat transfer properties. This means that
your wax will tend to solidify around the "cold" pipes -- and stay that way.
The high heat stored in the melted portion of the wax will be very slow to
transfer heat to the "cold" pipes. Do some experiments with a pan full of
beeswax on the kitchen stove, and you will see what a challenge it would be to
exploit these properties.
I would suggest that you stick with the more common water and antifreeze
I have good-as-new equipment, recently taken out of service because of
encroaching shade. Send email for details.
Posted by CraigNels on December 4, 2003, 2:02 pm
Thanks for your reply!
Actualy I have given this some thought. I realize now that my mention of it
was near the bottom of a lot of text on my web page so it probably got lost.
An excellent discussion of this can be found at:
They are using carbon fiber brushes, but this sounds like unobtainium to me (at
least in 55 gal quantities). I've opted for stacked metal sheets to enhance
thermal conductivity. Again, thanks for the reply.