Detached garage requirements

[tinstar751]

Hello all, newbie here. I have a detached garage that I want to be able to run a 1/2 HP garage door opener and a few LED lights. Nothing fancy. I know the opener uses a out 750 watts. I was planning on using 12v lighting. Generally speaking, the door would only be opened and closed about 3-4 times a week max as it is generally used for storage. I was hoping to use one battery, an inverter, charger controller and one panel. My problem is that I don't know how big of a battery or panel I would need. Any ideas would be greatly appreciated. Thank you!

 

[sunshine_eggo]

a, How many lights?
b, What wattage?
c, How many hours?

a * b * c = Wh of lights.

Assuming it takes a lengthy 60 seconds to open/close:

750W/60m/h = 12.5 Wh per open or close. Assume one cycle per day, 25Wh/day.

Add 25Wh/day to the calculated Wh of lights, and you have your total energy requirements.

Then you can determine your solar availability and size your battery/PV accordingly.

Refer to item 1 in my signature.

 

[tinstar751]

a, How many lights?
b, What wattage?
c, How many hours?

a * b * c = Wh of lights.

Assuming it takes a lengthy 60 seconds to open/close:

750W/60m/h = 12.5 Wh per open or close. Assume one cycle per day, 25Wh/day.

Add 25Wh/day to the calculated Wh of lights, and you have your total energy requirements.

Then you can determine your solar availability and size your battery/PV accordingly.

Refer to item 1 in my signature.

Thank you for the reply. The lights will bearly be used as during the day if at all as there are sky lights and it is plenty bright during the day. When used at night, it would be most likely just to pull a trailer in or out, 10min tops. Not sure of the wattage as I have not purchased them yet. I will check the info in your signature.

Thanks again!

 

[SparkyJJO]

I'm assuming there is no power source there at all right now from a nearby house or whatever? Just seems like a lot of fuss for almost never touched.

 

[tinstar751]

I'm assuming there is no power source there at all right now from a nearby house or whatever? Just seems like a lot of fuss for almost never touched.

Correct, it's at the extreme rear of the property. However there are a few family members that due to age etc, cannot open the door by hand due to its height. Also, loading in and out at night is a little tricky in the dark barn with a 44ft race trailer.

 

[sunshine_eggo]

It comes down to:

How much sun do you get?
How much energy do you want to use daily?
How much storage do you need to get you between charges?

Link #1 contains resources that enable you to answer the above and design a system.

 

[EastTexCowboy]

Hello all, newbie here. I have a detached garage that I want to be able to run a 1/2 HP garage door opener and a few LED lights. Nothing fancy. I know the opener uses a out 750 watts. I was planning on using 12v lighting. Generally speaking, the door would only be opened and closed about 3-4 times a week max as it is generally used for storage. I was hoping to use one battery, an inverter, charger controller and one panel. My problem is that I don't know how big of a battery or panel I would need. Any ideas would be greatly appreciated. Thank you!

Based on the information you provided and some assumptions/SWAG on the usage, it's going to be pretty low. I'm not a fan of the so-called "solar generators" but something like a Jackery or Bluetti might cover all your needs. I think Will has done some videos on one or both but if not there are a ton out there, or you can probably find folks on here with experience with those. As I said, I'm not a fan of those in general, but in your case it might be an easy solution.

 

[sunshine_eggo]

Based on the information you provided and some assumptions/SWAG on the usage, it's going to be pretty low. I'm not a fan of the so-called "solar generators" but something like a Jackery or Bluetti might cover all your needs. I think Will has done some videos on one or both but if not there are a ton out there, or you can probably find folks on here with experience with those. As I said, I'm not a fan of those in general, but in your case it might be an easy solution.

Damnit...

I hate those things too, but I think you hit on a solid point.

Let's hope the OP really wants to go DIY...

 

[EastTexCowboy]

Damnit...

I hate those things too, but I think you hit on a solid point.

Let's hope the OP really wants to go DIY...

I know. I can't believe I would ever recommend one of those things but this seems like an actual practical application. Ugh.

 

[DIYrich]

Double post.

 

[DIYrich]

1/2 hp motor is typically around 6 amps @120v, or 750 watts as you stated. However, that is running amps, and it could need all 15 amps to start, or 1,800 surge watts. That is what your inverter and battery will need to supply.

Assuming a 12v battery system, that is 150 surge amps, and 60 running amps. If you are doing LiFePO4 battery, I would get 150 to 200 ah of 12v battery. If you have cold winters, a lead battery may be a better choice. They surge well, handle the cold better, and you don't need much capacity.

Maybe a solar battery minder to charge a car battery. 12v car inverter that can output 1,800 watts.

 

[Decto]

The biggest draw is likely to be the inverter standby current if you want it live and ready to go all the time so you can open with a fob. Even a relatively efficient inverter will have standby of 10W so 240Wh per day, way above usage for lighting and running the door opener.

Usually you can rig up a isolation switch, but if it's forgotton you could discharge fully in a week or so just from the idle current if you don't panel to cover it.

Here in the UK you can get either 12V or Solar garage door openers.... though our garage doors may be smaller.
E.g. https://www.garage-door-automation.co.uk/seip_ts_solar.htm

 

[dcg9381]

Hello all, newbie here. I have a detached garage that I want to be able to run a 1/2 HP garage door opener and a few LED lights. Nothing fancy. I know the opener uses a out 750 watts. I was planning on using 12v lighting. Generally speaking, the door would only be opened and closed about 3-4 times a week max as it is generally used for storage. I was hoping to use one battery, an inverter, charger controller and one panel. My problem is that I don't know how big of a battery or panel I would need. Any ideas would be greatly appreciated. Thank you!

Having done separate structures a lot, if there is power nearby it's going to be a lot cheaper and easier long term to run power over to this structure. Even if that means 300-500'.

Math is "easy". What gets complicated is all the environmental conditions and off use cases. Legitimately, even in high sun states, we get a week without solar power here and there. In snow states, you need to be able to clear your PV panels. And in all cases, having equipment on "standby" draws power... Sometimes substantial amounts of power. You have to account for all that and pay for it.

Your garage door probably draws power sitting there. It's got a receiver.
Your inverter draws power sitting there. Some of them draw quite a bit.
Assume no matter where you are, that you need need to be able to handle 1 week without any sunlight. In Ohio, you'll need to be able to clear your panels from snow.

How far are you from a structure with power?

 

[tinstar751]

Thank you for all the replies and suggestions. I was already thinking about a cutoff switch of sorts to shut down the inverter when not in use. I hadn't thought about a Jackery-type device but it may be a good option based on price. I really appreciate all the help with this. I knew you folks could give some good advice. I will look at the pricing of all the different items needed and choose a solution.