Small solar on a budget

[Kenny Borel]

First thanks for adding me to your knowledgeable group. I am looking to add a small solar panel/battery system to a deer box stand. Advice more than welcome. Only going to have a couple LED lights used for 10-15 minutes at a time 1-2 times a week and to charge phone batteries. I'm looking at a 20 watt panel with a 10 amp charge controller that has built in USB ports and a 12 volt 20ah sealed lead acid battery. Will this work ok or what changes should I make? Looking at ebay for all my supplies. Battery, controller,& panel would run about $80-85. Thanks in advance !!

[SunEagle]

Hello Kenny Borel and welcome to Solar Panel Talk

First off a 20Ah 12volt battery can safely deliver only about 60 watt hours a day. (20Ah x 12V x 25% = 60wh). So if that is all those LED lights and phone chargers consume you should be ok.

For a 20Ah battery you should charge it with at least 2 amps which is more like a 30 to 40watt panel. A 20 watt panel may be too little and will certainly undercharge a depleted battery.

[Kenny Borel]

Thanks for the response. Lights will be used for very short periods of time and they are small. Phone only when needed.So you suggesting that I up my panel size to maybe a 50 watt and all else would be good as is? Also would you recommend mono over poly for the panel? Thanks !!!

[PNPmacnab]

Certainly, since trees and shading are likely involved. Just a tiny branch line will almost kill output for a portion of the day.

[azdave]

If all you need is a little light and a phone charger you can have all that in a portable power bank and forget the solar panel hassle altogether. I have one with three USB outputs totaling over 5 amps output available. You could have a couple of USB reading lights and room for a cell phone charge cord too. Some of the power banks have LED lights built-in. Will you not have an option to recharge a power bank in the car or at home after 2-3 days in the woods?

You can get 26,800 mAh units for $50 all over Amazon and eBay.

[SunEagle]

Thanks for the response. Lights will be used for very short periods of time and they are small. Phone only when needed.So you suggesting that I up my panel size to maybe a 50 watt and all else would be good as is? Also would you recommend mono over poly for the panel? Thanks !!!

A mono cell usually has a higher output than a poly but the poly seems to do better in low light. At the size of 50 watts it really doesn't matter unless you are installing it in a very shady area.

I also have to agree with azdave that if you want to keep it to a small budget then forget the solar part and just get a portable power bank that will meet your needs.

[Wy_White_Wolf]

First thanks for adding me to your knowledgeable group. I am looking to add a small solar panel/battery system to a deer box stand. Advice more than welcome. Only going to have a couple LED lights used for 10-15 minutes at a time 1-2 times a week and to charge phone batteries. I'm looking at a 20 watt panel with a 10 amp charge controller that has built in USB ports and a 12 volt 20ah sealed lead acid battery. Will this work ok or what changes should I make? Looking at ebay for all my supplies. Battery, controller,& panel would run about $80-85. Thanks in advance !!

While going straight by the numbers for a normal system the panel is a little undersized for the battery I wouldn't change it. This appears to be a weekend or 1 day a week system. I'd leave the panel slightly undersized as it will work better in holding the battery at float than a larger panel without overcharging the battery. Having the pulse from the charge controller at a lower amperage when in float will be gentler on the battery and it will have a few days to charge the last 5 to 10% of the battery.

I'm currently running a system further unbalanced that what you're looking at and the batteries are marine batteries that have lasted 7 years. I see no noticeable loss on the yet.

The charge controller could be sized smaller but may be the smallest you could find with USB hookups.

WWW

[Sunking]

Why waste any money on solar for this? For what you want takes so little light and battery that could fit in your pocket and work for a month.

[Kenny Borel]

I agree on being able to just charge a battery every now and then. Just thought it would be fun to dabble in solar for a fun project.. May not be worth it if I wont get the return I need from such a small system. May just get me a BIG battery and charge it 2-3 times a season. Thanks guys !!

[SunEagle]

For what it is worth. Having the word "solar" and "budget" in the same sentence is contradictory. Solar technology is not cheap and trying to dabble in it will cost you more than you expect.

I fully support anyone wanting to learn about the technology but I will also warn them that they need to keep an open mind on it's true cost and a open wallet to pay for it.

Good luck in your adventures.

[Sunking]

For what it is worth. Having the word "solar" and "budget" in the same sentence is contradictory.

Ditto budget and solar in a sentence is an oxymoron. If you want solar, money is no object. I understand you want to dabble, I get it. At least make it useful. Example Citizen make excellent Eco Drive solar power watches. There are attractive fine jewelry quality unlike an ugly toy Fitbit or Apple junk children ware and over pay for.