Dale Hodgins wrote:The wall will store heat according to its thermal mass. A very light wall can't store much. Water stores 5x as much heat in a given weight of material compared to cob.
Water heat capacity=1
Cob heat capacity=.2
ah, thank you for the data comparison. I found this
research on thermal water wall via cers.engr.psu.edu/files_public/winning%20papers/2011/UG_Ramal.doc "Thermal analysis of a discarded plastic bottle solar water" wall
Reading this now also
Greenhouses from plastic bottles
and I have an idea.. because I don't want to use limited resources constructing a structurally sound water-load-bearing wall
(!!) because other priorities are using those resources, I can fill larger bottles, put them on the ground at the back wall of the greenhouse, under the emtpy water bottle wall.... cloak them in black plastic and snug them up against rocks there.... to sink heat into the rocks and emit heat in the night up through the wall?