Solar powered barn? (gable fan, lights, heat, etc)

[zannej]

I have a separate thread about the barn I want built, but I want to delve specifically in to the solar powered aspect. I would like to have a solar panel mounted on the south wall of the barn either above or below the gable fan (not sure which would be better. Roof will slope down at 3/12 pitch east and west.
I need the barn to have some sort of gable fan to move air to cool it when it gets too hot. I know there are some little discs that can be used or there can be thermostats. I'm debating which would be better. A thermostat that is easy to see and allows for some wiggle room in terms of temperature would be nice. I'd like for it to turn on around 85 but turn off around 80 (internal temperature). I would also like to be able to turn it off manually with some sort of switch- either one on a cable that has a toggle/rocker switch, or wired to a wall-mount rocker switch near the doorway.
In addition to the gable fan, I would like to be able to run some 4' LED shop lights. I need to figure out how many watts they draw. I'd also like to have some sort of small space heaters that are safe for barns (that I could set somewhere the cows can't hit them). I don't think one space heater alone would work. I was looking at this 140w chickenhouse one and this 165w chickenhouse one. I'm not sure if either would be great, but I'd like to have at least something to generate warmth if we get more winter storms in the future.
I'm debating whether or not I would want at least one outlet to plug in a lamp or something.

I don't know near enough about solar power and I want to rectify that.

I saw some Eco-Worthy products that come with solar panels, charge controllers, batteries, etc and a DC powered fan (but the fan had bad ratings for motor failure). There's also Quietcool which has some "hybrid" fans. I believe they have some sort of inverter but they only come with 40w max solar panel.

I don't want less than 50w. I'd like to get a 100w (even if it might be overkill) and some sort of lithium ion battery (Eco Worthy has ones up to 50AH, but I think 20 or 30 would be OK). The shop lights would only be used when I need to go in and there isn't enough light. I believe 1 of my shop lights would be sufficient to light the entire inside part of the barn.

I also want a solar powered sensor light on the gable part of the very front. It might not get any sun so it will need a wire to run to a small panel. I may also want a light for the porch area. A single shop light for the lean-to would probably be sufficient. So, possibly 3 or 4 of my shop lights being powered for short intervals. The front gable light would be separate from my setup.

Things I believe I need:
Solar Panel (100w?)
Inverter (no idea what kind)
Lithium Ion Battery 10 to 30AH (maybe from Eco-Worthy)
Energy efficient gable fan (Quietcool or something else?)
Insulated battery clips/cables
Thermostat (energy efficient but easy to see/read and set)
Charge Controller (not sure what type)
Cable (12 or 14 gauge?)
Flexible Non-metal conduit
Rocker switch
1 or 2 gang switch boxes

I know they sell very slim lightweight LEDs that are rated for damp areas that I might be able to use and not draw a lot of power. I could use magnetic tape or double-sided sticky tape for some (if my barn's metal is magnetic- or I could us rare earth magnets or something).

Any suggestions? I don't want to spend a ton of $ on this, but I know it won't be cheap.

I'm at a loss when it comes to how many amps, watts, etc the controller and inverter will need to be.

 

[zannej]

More info: The solar lights are either 40w or 50w each (depending on which ones I use). Most likely the 50w version. They will only be on for short periods of time. The rest of the time I can have those cheap battery operated sensor LEDs that you stick to the wall with doublesided sticky tape.

I also am wondering if this gable fan with thermostat and humidity sensor could work if I got the right inverter or maybe even the 10" version. 12" uses 220w and 10" uses 180w.

I would likely only have 2 of the lights on at once and I could try to set it up so I can turn the fan off when the lights are on. Fan will not be on if I have a heater on, but I don't expect to need the heater often or for long periods of time.

 

[zannej]

So, I figure if I have everything running at once it would be 500w usage. But I won't be using the heater while the fan is on and vice versa. So, it wouldn't be that much, but I want enough juice to support that much. Would I need a 500w solar panel or would a 100w be sufficient with a decent enough battery?

Still not sure what sort of inverter and charge controller to get. Is it ok to go with a higher powered inverter? I think my friend knows about this stuff but he hasn't been replying to me much. He's got guests hogging his computer.

 

[SheepDog]

If you are planning on a battery big enough to supply the power then you need a solar supply that is big enough to keep the battery charged.
NOTE: you will need a battery and at least a 500 watt supply. It is always better to get an inverter and charge controller big enough to cover future expansion. Remember that your panels will never make 500 amps for more than a few minutes a day and as they age their output drops to 80% of new. All winter they will produce about 30% of rated output on the good days and considerably less on overcast, rainy or snow days. You are going to need additional power for more than half the year.

 

[zannej]

Thanks, Sheepdog. I wish there were solar panel experts in the area I could consult with, but Louisiana isn't big on renewable energy. I may end up having to go with regular electric & see about upgrading to solar later. I'm still interested in finding specific equipment to make it work though. We get a LOT of sun here at least, but then there's also a lot of rain. It's raining right now.

 

[PopPopT]

I'm far from an expert, but I'm kinda seeing that a 50w panel or a 100w panel wouldn't really be getting you much. A 12 volt attic exhaust fan could easily pull 100w all by itself. Granted, that would probably be running when the sun in shining. I'm not so sure a heater is a good match for a solar setup like you're thinking. The heat you'd get out of a 100w heater is pretty comparable to the heat you'd get out of a 100w light bulb, not much. Some LED lights would be good on a small system.

That's just my own gut reaction from what I read above. Hopefully, there will be others more qualified that will be along shortly. Good luck!!

 

[zannej]

I think what I'll do is go with regular power from that pole outside (didn't realize I still had that breaker box out there) and look for some sort of supplemental/backup solar power for emergencies. If not solar, maybe even wind turbine, but I'm hoping technology will improve and prices will go down. Not much chance of the latter though.

I still want a solar powered sensor light for the front at least. Need to find something with a little panel I can put on the roof ridge easily & have the light attach to the front gable end. I saw some indoor/outdoor battery operated sensor lights as well that don't stay on long but could work long enough to flip a light switch.

 

[PopPopT]

I don't know if this would be of any interest, but just for venting in the "attic" area...

Aura Solar Attic Fan | CFM: 205 6″ Diameter 2″ Tall Collar | Model ASF-6-C2 - Active Ventilation Products

(There are other options, just posted that as an example. It would be independent of anything else you'd be doing.)

 

[zannej]

Thanks, PopPopT. I'm not comfortable with roof penetrations- worried it will cause leaks. I'm ok with cutting in to the side though.

 

[INresponse]

I have this solar powered fan in my attic. I am pleased with it. When the sun is full and bright I can hear it working well blowing the heat out of the attic. When it is cloudy or overcast it does slow down, but if it is a cloudy day the attic doesn't get as hot. I have the solar panel aiming mostly straight up, just a slight angle so rain and snow (as it melts) will run off, so in the winter months it does not get direct sunlight and the fan is considerably slower which is fine with me, I just need a little air movement to prevent condensation inside the roof. It worked well this past winter, I had sign at all of condensation even when the humidity was higher than normal.
It does make noise, it is not loud or annoying, but it is a fan and as it runs you will hear it. Mine faces the street so it can be heard out front, but since most of my outdoor time is in back or on the side I don't here it.

ECO-WORTHY 25W Solar Powered Attic Ventilator Gable Roof Vent Fan with 30W Foldable Solar Panel

 

[zannej]

Thanks, INresponse! I wonder if a larger scale version will work for my application then. I could have solar for a backup in case power goes out.

 

[INresponse]

Thanks, INresponse! I wonder if a larger scale version will work for my application then. I could have solar for a backup in case power goes out.

It will move air, so it is helpful. There may be larger versions, I was looking for a size to fit my gable vent, a long enough cord between the solar panel and the fan based on where I was installing them (an inch further and the cord would have been too short, and a price point I could afford at the time.

 

[zannej]

If I do go ahead with solar I will have the panel fairly close to the fan as the fan will face the south. It's a large space so will need a lot of air moved though. Although, I suppose just having enough to move hot air out from up high might help. I'm hoping we can still hook to that breaker box that's nearby.

 

[INresponse]

If I do go ahead with solar I will have the panel fairly close to the fan as the fan will face the south. It's a large space so will need a lot of air moved though. Although, I suppose just having enough to move hot air out from up high might help. I'm hoping we can still hook to that breaker box that's nearby.

If the sun is out the attic will heat and the solar fan will run strong. If it is cloudy or overcast the attic wont be as hot and the slower fan speed wont be a probem. Just what I have experienced over the last year.

 

[zannej]

If the sun is out the attic will heat and the solar fan will run strong. If it is cloudy or overcast the attic wont be as hot and the slower fan speed wont be a probem. Just what I have experienced over the last year.

Sadly, where I live it can be hot as hell even when it's cloudy or dark. We have high humidity & the heat stays in the air-- particularly in metal buildings like I plan to have built.

 

[viking]

Here's something to think about, the best solar panels are the Mono-crystalline type, they don't loose their efficiency as much as other types do, also from experience, I highly recommend MPPT type solar controllers and get the highest voltage solar panels you can get, even on cloudy days that combination can give you a decent charge on whatever batteries you use, if you try to go cheap, you will probably never be happy. Another thing to consider is to find suppliers near to you, we've saved over $200 by picking up the solar panels, controller, inverter and other needs, shipping can get expensive.

 

[viking]

Zannej, if you go to the thread Solar Energy, I've posted a lot of pics on what I've done, I know my set up is overkill compared with what you need, but I present ideas to think about and the biggest thing that I put out there is to always use high voltage output panels with a MPPT solar controller. Our solar panels put out a solar maximum of 36 volts, I connected two for a series output of 72 volts, on a full sun day I actually get over 80 volts, frequently just as the sun is setting the total output can still be in the 70+ volt area, our batteries are 24 volts, that's what the inverter runs on and it's a Magnum Energy pure sine wave type that makes cleaner electricity than the grid does, so motors and electronics run cooler and more effaticiently than standard square wave or modified wave inverters, think of old tube type car radios, they had a vibrator tube that made the 12 volt battery voltage square wave to run a transformer to get high DC voltage to operate the tubes. Don Rowe, www.donrowe.com has an inverter business just north of Eugene, Oregon, that's where we got the 2,000 watt inverter/charger for our motorhome and the 4,000 watt 120/240 VAC inverter/charger for the emergency backup supply for our home, they offer various brands and sizes inverters often at greatly reduced prices than you would pay at an RV supplier. We got our solar panels at Grape Solar in Eugene, Oregon. The solar panels, solar controller and inverter/charger for the motorhome was from AM Solar that is located in Springfield, Oregon, just east of Eugene, I learned a great deal about solar systems from them and they have a good website for info www.amsolar.com . Just so you understand, high voltage panels equate to the number of cells a panel has, if you get panels with just enough voltage to charge a 12 volt battery then a foggy, cloudy or rainy day may keep you from getting a full charge on your battery. I'll add one more thing here, always keep DC connections as short as possible and wire sized properly, long runs of DC wires loose voltage, AC wires need to be properly sized so that they don't loose voltage over long distances from the inverter to the fans or lights. There are sites on the internet on wire sizing also sometimes local electrical supply dealers have wire charts for free.

 

[zannej]

Thank you, viking! I will have to look up that post.

 

[Biggkidd]

MPPT charge controllers are the only way to go if you're serious about solar efficiency. Ebay carries one called PowMr that has some good reviews for WAY less than my Midnite solar cost. I have one sitting here in a box waiting on my slow butt to setup and try out. Renogy panels have served us well. Personally I wouldn't even consider a 100w panel. We are using panels in the 300 watt range as they seem to have the best cost per watt average. Solar can be complicated IF you make it so otherwise it's mostly plug & play these days. Aims inverters have far out performed all the other less expensive inverters we've tried.

 

[zannej]

MPPT charge controllers are the only way to go if you're serious about solar efficiency. Ebay carries one called PowMr that has some good reviews for WAY less than my Midnite solar cost. I have one sitting here in a box waiting on my slow butt to setup and try out. Renogy panels have served us well. Personally I wouldn't even consider a 100w panel. We are using panels in the 300 watt range as they seem to have the best cost per watt average. Solar can be complicated IF you make it so otherwise it's mostly plug & play these days. Aims inverters have far out performed all the other less expensive inverters we've tried.

Thank you! Specific recommendations like this are very helpful. I'm really hoping they will expand solar power where I love so it will be more affordable. I also would love to get away from my stupid power company that has power go out for no apparent reason on sunny days. Second to last surge killed the power supply in my mother's computer (even though it was through a power backup unit/surge protector). The last one killed my landline phone (which was also through a surge protector).

 

[zannej]

Yikes, its been awhile and I thought I had posted links to stuff but apparently not. LOL. It's not looking like the barn will be feasible anytime in the near future.
So, I'm looking at finding a solution to power my pump house for my well system. I want to have at least one gable fan (not very large as there isn't much room- low roof with low slope.

It isn't very warm outside right now but it's already hot in the pump house.
I'm currently looking at solar powered chicken coop fans.

Any suggestions?