Small Barn Solar System

[Fsbell123]

Hi there, I have a small quail farm and I need to move my quail to a small barn I built. (20x36')

I need to power a total of (10) 100 watt bulbs and (2) 100 watt box fans. Only 2 of the bulbs will be used for 18hrs a day and the (2) box fans will be used 24x7. The other (8) bulbs will be used for 20-30 minutes on avg per day.

I'll get about 2.5-3hrs of peak sun....

I'm trying to size the system...what do I need to get? Is there a "pre-made" kit out there and which one would you recommend? The easier to assemble the better. This is not a "for life" setup so an economy or semi economy system would be great!

Thanks in advance for any and all help!

 

[Austan]

Per day by the numbers.
2x fans- 200x24hours=4800 watts
2x bulbs- 200x18hours=3600 watts
8x bulbs- 800x.5hours=400 watts
24 hours of consumption= 8800 watts (which I would call 10,000 watts minimum with system losses)
You need to generate that in 2.5 hours of sun so 10,000/2.5= 4000 watts of panels with ~850 amp hours @12 volts of storage (more for rainy/cloudy days).

With so little sun, can we assume it's a cold northern climate?
Can we also assume the 2x100 watt light bulbs are for heat and not light so no LED equivalent to save watts?

 

[gnubie]

If the lamps are for heating, would it be practical to use heated water instead? Solar thermal is much more efficient per area than PV and would slash the electrical storage capacity. A storage tank, a small circulation pump and small radiator in the area to be warmed along with the exterior collectors etc.

 

[snoobler]

Sorry, that is incorrect. Solar and Pv are basically similar in efficency. I think they always were close on par only pv was more expensive. Not the case now.

Cite please. PV is capped at about 20% efficient.

Direct solar heating is easily above 50% efficient.

 

[gnubie]

Cite? Why bother. Google is practically overflowing with endless useful information about the performance of solar thermal versus solar electric. If the budget and space permits one could install a more panels and run a heat pump water heater during the day but thermal will do it with less space and less expense (heat pump water heaters aren't cheap) and heat pump heaters are usually power (watts into water-wise) limited and make up for that lower heating rate by heating for longer... which sucks if you have a small collection time window.

Solar Thermal Shows Highest Energy Yield Per Square Metre | Solarthermalworld

The annual energy yield per square metre is much higher for solar collectors than for other renewable technologies, as the figure on the left shows. Compared to PV, solar collectors […]

www.solarthermalworld.org

Solar Thermal Energy - Watts per Area

Calculator for the achievable power of a solar thermal system on a certain area.

rechneronline.de

 

[gnubie]

Wrong. In bad weather solar thermal does work. Of course we are not talking apocalyptic weather, just bad. In the same circumstances that render thermal no good, PV is essentially useless too.

You really seem hell bent against solar thermal, that's fine. Just let other people make up their own minds.

 

[gnubie]

Sorry but practical experience here tells me that your appraisal of the performance of solar thermal is wrong. Plain, simple, wrong. In any condition that does not render a PV system all but useless there is plenty of heat gathered to heat water too. The sole reason you can even claim this stupid position you argue is your very large array. You even admit that yourself.

Now let's examine something here. Your array is capable of generating 90kWh a day. That's a huge system. Ever thought that not everyone has the space nor budget to do that, making thermal an even more attractive option? Hmm?

The opening post discusses a barn, 20 x 36' with 2.5-3.5 hours a day of peak sun.