Passive Solar

[Yabadabado]

Building a Geodesic Dome Greenhouse. Have 6 IBC containers, at 275 Gallons per, for passive solar heat. Filled with well water. The IBC containers have been painted flat black and are in an aluminum cage, with minimal contact between metal and plastic. The containers are 12' high, 8' wide and 3.5' deep. 24' diameter Dome allows sunlight for good portion of the day. Have access to 2 6x8 sheets of black opaque glass. It could be mounted on south side of cage. Question: Will glass add, detract or no +/- heat transfer to water?

 

[willard3]

It will heat the glass up and, if your enclosure is properly insulated, it will eventually heat the enclosure.

 

[Ceramicguy]

Why would you intercept the energy falling directly on a heat transfer surface with an emissivity above 0.8? What is more important is to allow the 5000 K peak radiation of the sun to be converted to heat in your flat black coated drums of water and then prevent the far infrared radiation from being reemitted to the outside environment. Low E glass will probably be a better choice. Bear in mind that the optical characteristics of glass we can see (eg color) cannot be extrapolated to the far infrared.

Bruce

http://accuratus.com

 

[Yabadabado]

Thank you both for your comments. While the black glass would look good, it is a greenhouse after all and function trumps aesthetics. Temperature regulation is very important in a greenhouse and the dome has presented unique challenges. Finding a material that has any R value which can allow the appropriate light transmission and be able to conform to the angles of the dome to name a few. We have come up with some unique remedies. Here's hoping they work. Again, many thanks.