Heating is more efficient with solar when direct solar heat gain is used, whether water or air is used as opposed to using PV to to make electricity to make hot water or air. Although by heating water one can have storage for non-sunny days.
PV can simplify the system and give storage.
The cost can get high though, low voltage dc water heating elements are not cheap when compared to there 240 vac counterpart and there realitivly higher wattage capabilities. A circulating pump might be needed as well as an air handler (small radiator).
I have never expierienced Southern California Winters so I have to imagine that the days are cool while the nights can get cold so storage might be nescessary. I've always heard the expression "Sunny California," so even when the days are cool I guess the Sun shines most of the time?
Would it be possible to construct part of the aviary as somewhat of a "greenhouse?" Using a thermal mass such as black tanks of water and or large stones?
The fan and light lend themselves well to PV modules. Simply add the wattages of the two and multiply that by the number of hours expected to run in a twenty four hour period, multiply that by five and then divide by a nominal voltage in order to get the amount of battery storage for about four days without sunshine.
Example;
fan 15 watts
lights 100 watts
totals 115 watts
X 10 hours
= 1150 watt hours
X 5 (20%)
= 5750 watt hours
/ 48 vdc nominal
= 120 amp hours of battery storage.
Now to replace whats used in a twenty four hour period within one good sunny day, first know the average number of hours of full rated charge from a PV module in your region, angled perpendicular to the Winter time Sun at noontime on the shortest day (Dec. 21).
I'am going to geuss at 5 hours. So;
1150 / 5 = 230 watts of PV array at 48 vdc nominal.
Whichever you chose you may not want to rely on one thing only. Always have a backup.
Hope this helps.
