Re: Yet another solar heated swimming pool--enhancements

Nick Pine <nick@vu-vlsi.ee.vill.edu> wrote:

>The straw bales under the pool itself could be spread apart to make 8 air
>ducts, each 6" wide x 16" deep, running from north to south...

>Here's a fix: forget the newspaper, make the ducts a foot wide, use 30 instead
>of 40 straw bales under the pool and put in 100 concrete blocks with holes in
>them, standing on end between the ground and the chicken wire ferrocement, to
>act as fins to conduct heat up to the pool bottom...

Better yet, forget the ducts and cement blocks and ferrocement, just build
the platform from strawbales and use a tiny pump and a 20' x 4' length of
SolaRoll, the EPDM rubber swimming pool tube-mat collector, under the south
edge vertical glazing.

Better yet, forget the store-bought pool and put a treated wood 2x4 frame
around the straw bales and line an 18' x 12' x 4' inner cavity with a single
piece of 20' wide EPDM rubber, folded up like a Chinese takeout box, so it
has no seams.

Better yet, make the solar collector out of another single piece of EPDM
rubber folded once into a 4' high x 12' long x 1" thick vertical V, with the
sides and top sealed in a 2x4 sandwich with silicone caulk between the rubber
sheets, a la Sven Tjernagel's 470 Pennsylvania site-built solar collectors,
(some still going strong), but vertical vs slanted, and filled with water,
vs a trickle down system, with some chicken wire under the north sides of
the 2x4 to limit the rubber bulging, and some glazing screwed to the south
sides of the 2x4s.

Better yet, make an 20' wide x 16' long x 16' tall cube with 4 of these
20 x 8 x 8' boxes, using 2 16' long x 8' tall site-built EPDM collectors on
the south face, 2 6 gpm pumps each having an 8' head capability, and 4
internal water cavities, each 16' long x 8' wide x 6' deep, to store 24,576
gallons of water at 130 F, ie 10 million Btu of solar heat for a nearby house
for a whole cloudy winter. This might be nice under a 16' x 16' walkout deck,
on the west side of a house... If one were going to drink the water, the inner
tank liners might better be pond liner material, not EPDM, and the collectors
might contain propylene glycol "edible antifreeze," with a heat exchanger
inside the tanks.

The pumps could be PV-powered of course. ("Bad move," says Sven Tjernagel :-)


It's a snap to save energy in this country. As soon as more people become
involved in the basic math of heat transfer and get a gut-level, as well as
intellectual, grasp on how a house works, solution after solution will appear.

                                          Tom Smith

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