How do I figure out solar or battery powered lighting with a timer?

brewer12345

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This is definitely off topic, but there are a lot of engineers and people who muck about with solar powered stuff, so I thought I would ask. I need to figure out how to light my quail coop for 15 hours a day or so. A modest string of LED lights will be more than sufficient, but the coop is away from power outlets. I'd like to set up an automated system with a timer and either replaceable batteries or a small solar panel. Is there a simple way to do this? What would I need to put all of this together? I know next to nothing about electricity and solar panels/batteries, so I am at a bit of a loss as to how to even figure this out.
 
It is not hard to set up a small solar system that works for you. The problem is it is going to be more expensive to install ($500-$1000), and to maintain (due to the battery) than running wires.

How far is the quail coop from the nearest power outlet?
 
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It is far enough and wet enough that running wires isn't something I am eager to do. If solar is that pricey, that is a non-starter as well. I sort of think that something like this should work to power the whole thing, but I don't know how to connect it to a timer and lights.
 
I figure you'll need a kit that has a solar panel with a rechargeable battery. Then you get a one of those Xmas lights timer and your light. Instructions for the timer should be on the box.

Your birds already get natural light for most of the day, so you only need the panel to add a few hours in the evening, right? I figure a moderate sized panel and battery should be able to do this without too much difficulty.
 
There's a lot of 12 volt stuff out there, batteries, timers and LED's. The battery can be just a common deep cycle 12V, there are a lot of 45 watt 12 volt panels and the timer will be the cheapest of all.

I use a 12 volt automotive LED and a battery to illuminate my "grillin" table;

32924191932_759a5e9098_z.jpg
 
I figure you'll need a kit that has a solar panel with a rechargeable battery. Then you get a one of those Xmas lights timer and your light. Instructions for the timer should be on the box.

Your birds already get natural light for most of the day, so you only need the panel to add a few hours in the evening, right? I figure a moderate sized panel and battery should be able to do this without too much difficulty.

This is a November through March kind of thing. Ideally I would set a timer to run LEDs that draw a few watts for 15 hours a day and forget about it for the winter.
 
On 2nd thought, the power required is not that high with LEDs, so the system can be smaller than what I first thought. So, perhaps $200-$300, using cheap Chinese components I have seen on eBay.
 
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There's a lot of 12 volt stuff out there, batteries, timers and LED's. The battery can be just a common deep cycle 12V, there are a lot of 45 watt 12 volt panels and the timer will be the cheapest of all.

I use a 12 volt automotive LED and a battery to illuminate my "grillin" table;

32924191932_759a5e9098_z.jpg

So if I go the solar route, I need the battery, panel, charge controller, timer and lights? If I could figure out how to do this with D cells it would probably be a lot cheaper.
 
Yup. 12 volt solar is quite common and quite cheap.

Forget "D cells" you need a rechargeable battery. Deep cycle, not an automotive "starter" battery.
 
What you need (price is from the first vendor on eBay that I see)

* A solar panel - 40W to 100W. Maybe oversized, but let's be safe here. 40W for $86. 100W for $120.

* A battery - let's use the common 12V marine battery. $80.

* A charge controller/load controller. The charge controller goes between the panel and the battery. It keeps the battery from getting overcharged. The load controller is between the battery and the load. It disconnects the load when the battery voltage is low, and keeps the battery from getting ruined by overdischarging. The controller I used is a brand-name unit with fancy features and costs more than $200. There's one as low as $13 on eBay. Others are around $50.

* A 12V electronic timer. $5.

* 12V LED fixtures. ~$1-10 each. There are all kinds on eBay.
 
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Maybe a little bigger...

You have to figure the amps your light will draw and the hours you run it. That will give you amp-hours. Then the panels rating watts (amps x volts) available to charge the battery. Consider sun hours and clouds. I would get a battery about twice what your lights need and a panel about twice that.

I can tell you for sure that the power you get from panels on a cloudy day is 10-20% of full rating. I know, I have them on my roof - :)
 
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You'd want a deep cycle battery. If you live in AZ and have sun almost every day, you might be able to get away with a regular battery. Deep cycle batteries are made to be run down - which is what will happen if you have a week without sunlight.

Have you looked into some low voltage lighting? If you have a receptacle outside, you can plug in a transformer and run low voltage wire just barely buried in the ground. Similar to what is done with landscaping lights. Might be cheaper.
 
Something like this big enough? https://www.amazon.com/ExpertPower-...coding=UTF8&psc=1&refRID=P4RTKY73ASYYA7JZBPSZ How would I figure out the battery size I need? Looks like I could get an inexpensive 20 watt panel and charge controller. The timers and lights cost next to nothing.

probably - but as you say you know little about this stuff, I'd suggest a more turn-key system. A Solar panel and controller designed to work with each other, from the same supplier, along with a 12V lead-acid battery recommended for that set up.

First - requirements:

How much light do you need, how many hours/day? Use 'watt-equivalents' based on standard 40-60-100 watt light bulbs, or 4W night lights if you are talking low level lighting, for reference - LED watts required will be about 1/4 of that.

How many days with little/no sunshine do you need to plan for?

Once you have those numbers, locating a 12V system should be pretty easy, and maybe pretty cheap.

-ERD50
 
Battery and panel sizing depends on the power that your LED will draw. For something as bright as a 60W incandescent, you need a 10W LED. The current that draws is close to 1A.

The 7-Ah battery costing $17 you list above theoretically powers the LED for 7 hr ( 7 AH divided by 1 A is 7 hours). With lead-acid batteries, you can use only 1/2 the capacity or the battery is ruined in just a couple of cycles. So, 3.5 hours of light with that battery.

PS. I would get something oversized, compared to what you think you need. It costs only a bit more, and you are happier in the long run. The battery will last a lot longer if you do not drain it down badly each night. The larger panel will give you reserve power to handle cloudy days.

PPS. If you find out you have excess power, another LED or two to light up the backyard and the path to the coop will take care of that. :)
 
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I might need something like a 5W LED (plus whatever a timer draws). So maybe half an amp draw, give or take, for maybe 10 hours a day (5 in the morning, 5 in the evening assuming I get some light during the middle of the day). 5 amp-hours, right? If I can use only half the battery capacity, I need at least a 10 Ah battery and probably something bigger so as not to push it. How do I figure out the theoretical solar panel size I need?
 
Battery and panel sizing depends on the power that your LED will draw. For something as bright as a 60W incandescent, you need a 10W LED. The current that draws is close to 1A.

The 7-Ah battery costing $17 you list above theoretically powers the LED for 7 hr ( 7 AH divided by 1 A is 7 hours). With lead-acid batteries, you can use only 1/2 the capacity or the battery is ruined in just a couple of cycles. So, 3.5 hours of light with that battery.

But that assumes you get sunshine to recharge it every day. I think he will want to have several days battery supply for margin, and a panel big enough to keep it charged for an extended cloud period, as say 10% sunshine for 5 hours/day for a week (or whatever you might expect in that area, but week of winter overcast sky isn't that uncommon here)? So a panel rated at ~ 2x the daily draw - so for 10 Watts for 5 hours/day = 50 watt-hours (edit - I crossed with brewer's post, but he mentioned 5W for 10 hours, so same watt-hours!), you need 10 Watts from the panel for 5 hours. If that is just 10% sunshine, that's a 100W panel.

OK, that might be overkill, but you've got to start with the numbers. Maybe it is even practical to bring the battery in to charge it for a few hours if there is extended overcast period (or run a cord temporarily to charge from the house)? It all depends how far you want to go.

-ERD50
 
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But that assumes you get sunshine to recharge it every day. I think he will want to have several days battery supply for margin, and a panel big enough to keep it charged for an extended cloud period, as say 10% sunshine for 5 hours/day for a week (or whatever you might expect in that area, but week of winter overcast sky isn't that uncommon here)? So a panel rated at ~ 2x the daily draw - so for 10 Watts for 5 hours/day = 50 watt-hours, you need 10 Watts from the panel for 5 hours. If that is just 10% sunshine, that's a 100W panel.

OK, that might be overkill, but you've got to start with the numbers. Maybe it is even practical to bring the battery in to charge it for a few hours if there is extended overcast period (or run a cord temporarily to charge from the house)? It all depends how far you want to go.

-ERD50

Allegedly 300 days of sunshine here in Colorado. A week of no sun would be unheard of, but a couple days would not. In that case I would have no issue with either bringing the battery into the house to top it up, or running an extension cord out to the battery. It would be a few times a winter and if it would greatly decrease my solar panel needs it would be worth it.
 
Top cost is the panel, second is the battery.

If you run the battery way down (below 50%) it ain't gonna last long.

You can spend the dough now or more dough later.

A lot more after you get sick of replacing batteries and then get a bigger panel and a bigger battery.

How much dough you got?
 
Top cost is the panel, second is the battery.

If you run the battery way down (below 50%) it ain't gonna last long.

You can spend the dough now or more dough later.

A lot more after you get sick of replacing batteries and then get a bigger panel and a bigger battery.

How much dough you got?

Yeah. At some point it isn't worth it. I can potentially move the coop close to the house for the winter if I have to and at that point I will have access to an AC outlet.

I think I understand battery sizing. How do you back into panel sizing (i.e. how do I convert AH to panel wattage rating times the number of hours of daily sun)?
 
Oh, and I really appreciate all the comments and education. I am starting from knowing zippo about any of this. After being in a rut for a long time, I am trying to push myself to learn new things that are out of my comfort zone. I may conclude that it isn't worth the ducats to put a solar panel system on the coop, but at least I will have learned something new.


FWIW, I pretty quickly figured out there was no way to power a bird bath deicer economically. If I do opt for solar lighting, I will do a variant of this to try to keep the water from freezing: https://www.hemmings.com/blog/index.php/2007/04/26/almost-free-garage-heat-just-drink-a-lot-of-soda/ I thought it was a neat idea and I could fool around with the size of the thing to get it right.
 
I just looked up my generation for January. 272 KWH. I have a 3.6 KW system on the roof. If it did 3.6 KW for 31 days, 24 hours a day it would have done 2700 KWH.

So 10%, but it was cloudy and stormy and the sun was low in the sky. It's also a top of the line SunPower array.

It's best to oversize when in doubt. But hopefully, the above data will help you to figure out what you need.

By the way, why do you need the light? You could just flip a switch when you are there. Do the birds need light 15 hours in the winter? But not heat?
 
By the way, why do you need the light? You could just flip a switch when you are there. Do the birds need light 15 hours in the winter? But not heat?

The quail will huddle up and stay warm when it gets cold. The challenges I face in the winter are that I need to keep their water from freezing and I need to ensure they have 14 or more hours of light a day to keep them laying.

Based on your generation numbers from your panels, it sounds like this is not a feasible choice for me given the number of hours I need the light to be on. Ah well. Makes me wonder why so many people are having PV systems put on their houses, though.
 
.....
Have you looked into some low voltage lighting? If you have a receptacle outside, you can plug in a transformer and run low voltage wire just barely buried in the ground. Similar to what is done with landscaping lights. Might be cheaper.

I like this idea, it's cheap and he could run the wires inside that low cost plastic conduit pipe all sealed together or even a garden hose to make it more water proof.
 
In CA it's easy. High rates and "tiers", not to mention the 30% Fed tax credit.

I'm very happy with the results of my install indeed - :)

But alas, no credit for the quail coop...
 

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