Solar panels, batteries, charge controllers, to run gable fan & shop LEDs

[zannej]

I'm trying to learn more about solar panels & options for things that can use it.

I already made a thread about wanting a gable fan in the barn I'm going to have built. I saw there are some that are DC/solar panel. Some can run without batteries, others use a charge controller and a batter. Some batteries have built in charge controllers, and some fans are "hybrid".

Ultimately, what I would like to have is a system where my barn can have a gable fan that can run even at night if it is hot but I would also like to be able to hook up two LED shop lights (they are 4' long). I need to check the specs on them, but they are extremely bright. They don't use much power as far as I know.

I as looking at an Eco-Worthy fan kit with solar panel, battery, charge controller, etc but the fans themselves had bad reviews. They have some nice lithium ion batteries that have 10AH, 20AH, 30AH, and 50AH. The 20AH seems like it would be sufficient to me. But I'm confused about the charge controllers, how many amps I would need, the inverters, etc.

I will need something that can power all those things and possibly some sort of ceramic space heater (in a spot where the cows won't be able to touch it).

My thoughts on what I'd need:

• 100w solar panel (would this be enough?)
• 10 or 20AH Eco-Worthy (or other) lithium ion battery
• energy efficient gable fan (can be DC or AC)
• Inverter of some sort? (no idea what type I'd need)
• Charge Controller (again, not sure what kind I'd need)
• Cables to connect everything (need advice on what to get)
• LED shop lights (I have them but need to see how much power they draw-- they are 4' long)
• Some sort of barn-safe energy efficient heater to warm the general area if it gets below freezing
• Master power switch to turn it all off in a pinch
• Individual power switches (1 for lights, 1 for heat, 1 for fan)

I'd also like a solar powered sensor light on the outside of the front of the barn (not sure if it will ever get sunlight so I might need to one with a detached mini solar panel so it can be put in the light)

Barn will be closed in with a 6'w x 7' high roll-up door. Walls will be 12 gauge steel but will be insulated. I can set up some moving blankets as a windbreak or close the door when it's very cold. We don't get freezing weather very often-- that once-in-100yrs winter storm situation aside. It has been getting colder during winters as of late though. My main concern is keeping them safe & dry when it rains and cool during summer.

I don't want to get the cheapest stuff that won't work or will die out, but I also don't want to spend too much.

There are so many products out there I'm not sure quite were to begin.

Also, would this heater be sufficient? Or more than one of them? (I know, it's for small animals) https://www.amazon.com/petnf-Chicken-Efficient-UL-Compliant-11-81x15-74/dp/B08J7Y1T2S/
or this? Amazon.com

Or something completely different? (I intend to put it where they can't actually touch it)

 

[zannej]

I'm adding pictures of the layout. I think I could get away with a single 4' shop light on the inside, one in the lean-to, and one in the porch area.

 

[ctviggen]

That is a complex question. Or set of questions. Do you want light at night? How would the fan work in terms of night/when it's cold?

To me, this seems like hours of research. Or expense. For instance, here's a 600W solar panel kit from Costco:

https://www.costco.com/grape-solar-600w-off-grid-solar-panel-kit.product.100696623.html
About $1,000, and doesn't include a 12V "deep cycle" (whatever that means) battery. It produces 1,800 watt-hours per day. That heater you linked was 140W, which means you'd get 1,800watt-hours/140watts = almost 13 hours of heat. (If my calculations are correct.) But then nothing else.

Those LED strips can run 30-40+ watts each. This one is 40 watts (and this is just a random one I selected):

https://www.amazon.com/FaithSail-Wr...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
Three of these is 120 watts, and of course you'll use these at night, when you're not generating electricity.

But to run 3 of these and the heater and the fan, even for spending $1,000, you're not getting a lot of time. But if you could make it so the fan wasn't running when the lights were, you'd get more time.

I'm afraid I'm at the limit of my knowledge.

 

[havasu]

The solar gable fans suck. They don't have enough power to blow out a candle.

 

[zannej]

Thank you, @ctviggen. I don't intend to have the lights on for long. I would only need it when checking on things and maybe grabbing some feed. They should not need to run for more than a few minutes. I suppose I could shut off the gable fan when turning the lights on if necessary. I could always get those battery powered wall-mount (with sticky tape) sensor lights for inside for when the cows move around to act as sort of a night light for them.

I've seen some good reviews on a few of them, but the main complaint was motors burning out. I'm hoping that if I get the right battery and solar panel setup I'll be able to get something going.

This one seemed to have decent ratings and has a digital thermostat & humidity sensor https://www.amazon.com/dp/B07T75SS7V/ using 180w or the 12" version https://www.amazon.com/gp/product/B07T81RKH8/ using 220w but it's not necessarily designed for solar. I'd need a strong enough inverter, but know very little about inverters.

The shop lights I'll use will either be https://www.amazon.com/gp/product/B074QQDPR9/
or https://www.amazon.com/gp/product/B01DBFG1TO/
So 50w max for each light I think.

I'd turn the gable fan off when the heater is on (if I ever need to use the heater). Although, worst case I could see if the barn installers can get power from one of the poles in my yard that is on the way down to the barn. Used to have a breaker box on a pole out there somewhere but neighbors stole it. I'll have to investigate to see if there's anything left to draw from. Could I do a trickle-charge dual-input for the battery if I had it get power from the house but go solar if the power is off?

 

[oldognewtrick]

The solar gable fans suck. They don't have enough power to blow out a candle.

Same with solar power roof vents.

 

[zannej]

So, I'm thinking of going with one that either draws 220w (the 12" one) or 180w (the 10"). Being generous, with everything on at the same time it would be 500w max use. That's with a heater, a 220w gable fan, and all three 50w lights. But, chances of using heater and fan at same time are nil.