Jerry, My only problem is that the months I really need the solar heat input, I have almost not sunlight. Starting in November and continuing through January and part of February, we have over 50% of the days extremely overcast and the rest cloudy. The Sun is at such a poor quality December and January, it will not even raise the greenhouse temperature enough to keep the furnace from running with the thermostat set at 55 F on the few sunny days we do get. I have tried several passive solar systems in the past and they have never given me enough heat to justify their cost.
Tom /-------------------------------------------------------------------------- | Tom Hillson Orchid Grower Specializing In | [EMAIL PROTECTED] Paphs, Pleurothallids, & Epi's | http://www.orchids.iastate.edu --------------------------------------------------------------------------- |"There is always room for one more Orchid!!" On Jul 30, 2008, at 6:57 AM, Gerald Fisher wrote: > Re: 4. "There are many active solar options that can be retrofitted > to an > existing greenhouse. .... Another option with this would be to plumb > the > black plastic water barrels together and make a closed system with > the black > plastic flexible piping in the peak and combine passive and active > solar > together to supplement the greenhouse heating. It would require a > circulating pump that is run only during the day. I plan on > enquiring into > photoelectric cells to run the circulating pump." > > It has been about 30 years since I was doing reading on closed loop > passive > solar collectors but I seem to remember that a circulating pump > would not be > needed. The heated water would gradually rise and then return as it > cooled. > At night the system would 'stop' when the system reached temperature > equilibrium. > > Jerry in IN > > > _______________________________________________ > the OrchidGuide Digest (OGD) > [email protected] > http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
