[Greenbuilding] Insulation Under Snow Melt Slab for sidewalk

[nick pine]

"Michael Zyla" <mzyla at verizon.net> says:

See  <http://www.concretenetwork.com/concrete/snow_melting_systems/>

>... The fluid is warmed to temperatures of 140 to 180 F to provide 
>sufficient heat for snow melting.

Wow. Why not flow 50-60 F groundwater over the driveway, with a 
plastic-film-lined trench full of stones and water on each side to rewarm 
the water?

"Erin Rasmussen" <erin at trmiles.com>

>These are pretty pictures of some passive solar...

http://www.scribd.com/doc/65208674/Passive-Solar-Architecture-Images-of-Passive-Solar-Buildings

Eeeww. Direct gain, aka "direct loss." Very expensive compared to passive 
solar air heaters, with a much lower solar heating fraction.

Nick