skeezics (in firstname.lastname@example.org) said:
| On Thu, 17 Nov 2005 09:02:03 -0600, "Morris Dovey"
||  Warm (less dense) air always rises above cooler (more dense)
||  The glazed area of a panel determines the amount of energy
|| available for capture.
||  The goal is to get heat *out* of the panel and into the heated
|| space, *not* to maximize the temperature inside the panel. Remember
|| that heat and temperature are *not* synonyms.
||  The panel joinery and glazing needs to be as close to airtight
|| as you can manage.
||  For a given panel design, taller panels will generate higher
|| temperatures - and it /is/ possible to build a panel capable of
|| catastrophic self-destruction (so don't get _too_ greedy!)
| after reading just a
| little bit i an concidering a panel about 4 feet wide and 6 to 8
| feet high and using 8" flex for the in and out pipeing. i have a
| couple of 6" computer mainframe fans that would assist in air flow.
| does this sound feasible?
Depends. Any kind of ducting will impede airflow - so it'd be
appropriate to ask if you really need ducting. If you use ducting you
don't really need and incorporate a fan to make up for having used it,
you're wasting power. How will this setup behave when the fan is
switched off or when the power fails?
I'd try for a design that uses principal  to obviate ducting and/or
fan. If you want a fan, put it near the ceiling and use it to blow
warm air toward the floor, so that the heat (from whatever source) is
better distributed. If you want to use ducting, use it with the fan to
draw the warm air from near the ceiling and blow it across the floor
(a concrete floor can work passably well as a thermal "flywheel" to
temper night temperature drops).
If you want to get fancy, control the ceiling fan with an air
conditioning thermostat near the ceiling.
I'd want the bottom of the panel above the level where termites and
carpenter ants might be inclined to make a meal of it. The top of the
panel discharge shouldn't be higher than your ceiling. Work backward
from there to determine the best panel height.
DeSoto, Iowa USA