Inexpensive solar option for barn power?

[alwaysFlOoReD]

Ryobi also has 12V chargers. At least I bought one for work several years ago.

 

[TimberMan]

Thanks folks! Just to confirm a few points...it is correct that I don't "need" 120v; I am only looking for a few lights and trickle chargers for this phase of the project which seems like it would be easy to run on low voltage. My master plan however, is to build another structure next to this one that would be a dedicated wood shop with climate control and at least a 200a service. When I build that building (which could be 10-years+ away), I will pull a fresh meter and service from my transformer and electrify both buildings. Perhaps I should rough in a few circuits for the future and energize them with 12v or one of the small solar generators I see mentioned.

 

[38Chevy454]

I used to have a small 15 or 20 watt solar panel, connected to two 12vdc SLA batteries that ran my gate opener at old house. Panel was about 15x18 inches and had a small controller built in. Kept batteries charged even in short winter days and opening/closing gate 4 or more times per day. Mounted panel on fence postangled facing south. Bought panel off ebay if memory is correct.

 

[Beerhippie]

Thanks folks! Just to confirm a few points...it is correct that I don't "need" 120v; I am only looking for a few lights and trickle chargers for this phase of the project which seems like it would be easy to run on low voltage. My master plan however, is to build another structure next to this one that would be a dedicated wood shop with climate control and at least a 200a service. When I build that building (which could be 10-years+ away), I will pull a fresh meter and service from my transformer and electrify both buildings. Perhaps I should rough in a few circuits for the future and energize them with 12v or one of the small solar generators I see mentioned.

For future-proofing, it's awful hard to beat surface-mounted conduit. Easy to modify at any time. Same goes for plumbing, but I might be in the minority of interior design theoreticians here.

 

[dcg9381]

I used to have a small 15 or 20 watt solar panel,

This will work for a gate and moderate use with a decent battery. But the OP is going to have "continuous draw" from those trickle chargers. And he's going to need to account for days / perhaps a week of no sunlight (say overcast week).

He needs a PV charge unit that has output control (low battery protect). And for the cost, just throw AT LEAST a 100 watt panel up there.

It's fine to start "small" with one panel and one battery, adjust as needed, just design for it.

 

[Beerhippie]

This will work for a gate and moderate use with a decent battery. But the OP is going to have "continuous draw" from those trickle chargers. And he's going to need to account for days / perhaps a week of no sunlight (say overcast week).

He needs a PV charge unit that has output control (low battery protect). And for the cost, just throw AT LEAST a 100 watt panel up there.

It's fine to start "small" with one panel and one battery, adjust as needed, just design for it.

For trickle-charging, daylight hours are plenty. I've also installed systems--one at a friend's barn, one at an off-grid ski area--just to keep vehicle/equipment batteries at full charge. Check, of course, for parasitic loads and eliminate them first.

 

[dcg9381]

For trickle-charging, daylight hours are plenty. I've also installed systems--one at a friend's barn, one at an off-grid ski area--just to keep vehicle/equipment batteries at full charge. Check, of course, for parasitic loads and eliminate them first.

I agree, but these things are going to "sit" there and if the OPs weather is anything like ours, it's possible for 3-5 days of solid overcast. So during that period, you're 100% on discharge. Even floating trickle is going to draw down. There is a constant parasitic load with a trickle charger, unless to OP is disconnecting it.

I think we're talking about different use cases. I'm talking about a case where things are connected to trickle for most of the year, not odd hours during the day when not in use....

 

[Beerhippie]

I agree, but these things are going to "sit" there and if the OPs weather is anything like ours, it's possible for 3-5 days of solid overcast. So during that period, you're 100% on discharge. Even floating trickle is going to draw down. There is a constant parasitic load with a trickle charger, unless to OP is disconnecting it.

I think we're talking about different use cases. I'm talking about a case where things are connected to trickle for most of the year, not odd hours during the day when not in use....

My outdoor lighting system is working on heavily overcast and snowy days in the winter... at 45 26 N, in Oregon. The sun set at around four this afternoon (9,800' mountain range to the south and west) and won't rise 'till about seven tomorrow. 24 W panel, 24 AH of battery--haven't actually added up the total draw.

If the batteries you're trying to maintain aren't experiencing any parasitic loads, you'll have plenty to keep going through the shortest, darkest days south of about 54 N.

 

[dcg9381]

My outdoor lighting system is working on heavily overcast and snowy days in the winter... at 45 26 N, in Oregon. The sun set at around four this afternoon (9,800' mountain range to the south and west) and won't rise 'till about seven tomorrow. 24 W panel, 24 AH of battery--haven't actually added up the total draw.

Good to have different data points. I had a 75 watt panel and 100Ah of battery, but it was powering POE cameras and a gate. If we had a week of overcast, I was opening the gate by hand... Probably a total draw thing, but the 12V to 12V battery maintainers will have "some draw" just don't know how much.

 

[Beerhippie]

Good to have different data points. I had a 75 watt panel and 100Ah of battery, but it was powering POE cameras and a gate. If we had a week of overcast, I was opening the gate by hand... Probably a total draw thing, but the 12V to 12V battery maintainers will have "some draw" just don't know how much.

The motion/occupancy controllers I use for the lights in the Conexes also have some draw--I need to measure that, as I didn't include it in my calculations for panel/battery size.

 

[the shifty jesus]

A friend recently picked up an EcoFlow power station at Costco to manage storage and expenditure in a 12x18 shed. He’s utilizing used solar panels on the roof that he scavenges on Marketplace and Craigslist. It’s pretty impressive, and able to power lighting, a couple sewing machines, and a small A/C