Help Off Grid Chicken Coop

[scotty16]

We are having a problem with the water freezing at the chicken coop and there is no way to get electricity to it. I think if I could get a 40 watt bulb to burn at night near the metal watering can it would keep it from freezing. What would I need to make this happen? How many panels and what size, what size batteries and how many? In another lifetime I was an electrician but it was all A/C current and certainly not solar. I have a huge open field to set the panels so plenty of sun. I am in VA.

Thanks,
Scotty

[Sunking]

Scotty first step is determine how many watt hours you need each day. Real simple Watts x Hours = Watt Hours. So lets say you want to run that 40 watt bulb 10 hours, then 40 watts x 10 hours = 400 watt hours.

To find the right battery is pretty simple once you know how many watt hours, and what battery voltage you are going to operate at. With 400 watt hours a 12 volt battery is practical. So the battery Amp Hours capacity [Daily Watt Hours x 5] / Battery Voltage. So using the example above [400 wh x 5] / 12 volts = 166 AH battery @ 12 volts. So you are looking for a 175 to 200 AH 12 volt battery. A good fit would be a pair of 6 volt golf cart batteries wired in series in this example.

Panel wattage is easy to determine once you know how many watt hours you need each day, and how many Sun Hours you have during the day. There are a lot of ways to find Sun Hours for your area. PV watts is about the best using you rzip code or Lat Lon. For a battery system you have to use worse case for time of year use. In your case December and January an din winter you only get anywhere from 1 to 3 Sun Hours depending on your location. For this drill let's say 2 Sun Hours.

OK to find panel wattage we need a 3rd peice of information, which is charge controller type. From experience I know you will want to use a MPPT controller because it will be the least expensive option. So if using MPPT you need a correction factor of 1.5, and 2 if using PWM.

OK Panel Wattage = [Daily Watt Hours x Controller Correction Factor] / Sun Hours. So in this example [400 wh x 1.5] / 2 sh = 300 watts.

Last is controller size in amps. For MPPT Amps = Panel Wattage / Battery Voltage. So 300 watts / 12 volts = 25 amps.

Done.

[scotty16]

That's exactly what I needed! Thank you!!

[Sunking]

That's exactly what I needed! Thank you!!

Wait until you price it out.

[Shockah]

Wait until you price it out.

Why 40watt bulb?

I would first test a 7w night light bulb, and go bigger only if needed.

Smaller bulb = smaller system = cheaper

[SunEagle]

Why 40watt bulb?

I would first test a 7w night light bulb, and go bigger only if needed.

Smaller bulb = smaller system = cheaper

Well the idea is to put enough "heat" into the chicken coop to keep water from freezing. You will get very little heat from a 7 watt bulb to overcome freezing temperatures. Even a 40 watt bulb may not provide enough BTU's depending on how big the coop is and how cold it gets.

[Sunking]

One would think putting a heating element in the water is the most efficient.

[SunEagle]

One would think putting a heating element in the water is the most efficient.

Yeah but those immersion heaters are usually very high wattage.

Better to use some type of infrared heating lamp in an enclosure next to the water bucket. It will still cost a lot of money to build an off grid system to do that too.

[Robert1234]

From experience..... Using a light shining onto the watering can is extremely inefficient.

Take a plastic bucket (I use one with low height like you use for changing oil). Put an old towel inside it for insulation. Take a string of minature Christmas lights and put them on the towel. Put your chicken's automatic watering can on top of the makeshift heater. Mine will keep the water melted down to single digits F. Goal is to just keep the water at 32-33 F maximum (just melted), not really warm it up. The birds are fine down to 0 F with no heat so long as you have nice roosting bars for them to sleep so as to keep their feet from getting frost bitten.

Like others said above, getting your wattage down as low as possible will be the key for you to make this project viable. Use as short a string of lights as you can so as to minimize your wattage, or you may even be able to use one of those reptile under tank stick-on heaters (they are only 10-20 watts or so) if you place the can on top of a well insulated stand. That experiment is up to you. I just used what I had available.

P.S. Normally I just put the watering can inside the greenhouse at night and bring it back out in the morning, although I will use the light heater setup during the day whent the temps won't get above freezing.

[J.P.M.]

From experience..... Using a light shining onto the watering can is extremely inefficient.

Take a plastic bucket (I use one with low height like you use for changing oil). Put an old towel inside it for insulation. Take a string of minature Christmas lights and put them on the towel. Put your chicken's automatic watering can on top of the makeshift heater. Mine will keep the water melted down to single digits F. Goal is to just keep the water at 32-33 F maximum (just melted), not really warm it up. The birds are fine down to 0 F with no heat so long as you have nice roosting bars for them to sleep so as to keep their feet from getting frost bitten.

Like others said above, getting your wattage down as low as possible will be the key for you to make this project viable. Use as short a string of lights as you can so as to minimize your wattage, or you may even be able to use one of those reptile under tank stick-on heaters (they are only 10-20 watts or so) if you place the can on top of a well insulated stand. That experiment is up to you. I just used what I had available.

P.S. Normally I just put the watering can inside the greenhouse at night and bring it back out in the morning, although I will use the light heater setup during the day whent the temps won't get above freezing.

I know less than nothing about chickens or chicken coops, but, FWIW I'm pretty sure I like your style and common sense version of appropriate technology - kind of a breath of fresh air, for me anyway. Maybe if I was a chicken in your coop I'd feel different (my feet get cold easily), but I probably wouldn't die of thirst. Nicely done.

[Robert1234]

...Maybe if I was a chicken in your coop I'd feel different...

LOL.. That's some funny stuff

[J.P.M.]

LOL.. That's some funny stuff

Thank you, but I was serious about the rest.

[Shockah]

Well the idea is to put enough "heat" into the chicken coop to keep water from freezing. You will get very little heat from a 7 watt bulb to overcome freezing temperatures. Even a 40 watt bulb may not provide enough BTU's depending on how big the coop is and how cold it gets.

I thought the light bulb would be placed under the water bowl (because heat rises), not above it.

[J.P.M.]

I thought the light bulb would be placed under the water bowl (because heat rises), not above it.

More accurately, heat goes from where it's warmer to here it's colder. Air warmer than its surroundings "rises", but only in a gravity field or as the acceleration vector in other fields.

[inetdog]

More accurately, heat goes from where it's warmer to here it's colder. Air warmer than its surroundings "rises", but only in a gravity field or as the acceleration vector in other fields.

But fortunately for life as we know it, ice also rises (floats.)