Posted by Tater on September 28, 2006, 1:58 am
Has anyone come up with a simple setup for a pv panel and a lower power
fan to help pump air thru a thermal panel? until my experimentation is
done, i'd like to see if somone has come eup with something
Posted by David Dawson on September 28, 2006, 4:14 am
It occurs to me that when the sun shines you have both light and heat, so if
the pump runs right off the solar photovoltaic panel, it does its work only
when the sun shines and not when not needed.
You'd need to know the required flow rate and losses to calculate the fan
power needed. If the fan varied its thrust in proportion to the voltage
then maybe you'd get a varying flow as needed? I'm not an engineer but I
can see that a simple solution should exist.
Hope this puts you on the right path.
If you wrestle in the mud with a pig.
you both get dirty, and the pig likes it.
-- Dave Dawson
Posted by SJC on September 28, 2006, 4:50 am
Here was a link from a previous post. Most of the way down the page you
will see two 12v fans coupled together with the right spacing. I see no
reason why you could not power these fans using a 12v PV panel.
Posted by schooner on September 28, 2006, 10:12 am
Cansolair has a PV option for their commercial panels, however I believe the
panel is used to charge a battery which in turn drives the fan. The issue I
see with this type of setup is the lower flow rate you will probably get
from the fan. Our panels use a 239CFM fan on the inlet to end up driving
140CFM on the outlet, so you need a decent sized fan to move enough air.
You can use a smaller fan but will probably give up some efficiency as the
panel will be heating more than you will get out of it at lower airflow.
You need to experiment to see if more air or higher temps give you a better
overall BTU output. It is a balancing act.
The other downside is the cost of the PV panel itself. It is much cheaper
to run a 120V fan for all the power they draw. The cost of the PV will add
a lot to the payback time of the setup IMHO and adds nothing to efficiency.
Posted by Tater on September 28, 2006, 9:20 pm
not really worried about payback, was just wondering about it.
part of the reason would be to push warm air thru ducting to the
northenmost part of a room to help distribute hear, the other is for
installation in a building that may not have AC, and yet another reason
is that the unit would not need a thermostat or other control mechanism.