sizing earthen thermal storage

[billn]

I just installed storage cells under my house using quarry fill with water circulation tubes. 3 separate insulated containers totaling about 80 tons. If I could heat them up to 110 deg F and deplete the temperature to 90, assume a 30 deg F. delta T, how many BTU's could I get out and at what rate ?<br>

 

[MikeVV]

Have you done any experiments to determine the heat tranfer efficiencies and caloric properties of the rock? Have you measured the insulation capability of the containers - perhaps by filling them with a known amount of energy and allowing them to cool over time?

 

[billn]

Mike, <br>
I have not done any experiments like that yet. The system is not "on line" yet. I am still building the house over it. I Once it is piped I will be able to do such testing. The media is a known quantity. It is mostly basalt. The particle size ranges from 3/4" to dust. It was compacted to about 95%.<br>
It is surrounded by 2" extruded polystyrene foam boards.

 

[a31ford]

Bill, hoping your e-mail is still valid, how is this project going ? I am very intrested in seeing some results.

g.