Small solar power station with automatic transfer?

[litleboy]

Hello,

I've watched numerous videos trying to determine if what I'm looking for even exists or what feature name to search for.

I aim to connect equipment (like a refrigerator or small AC unit) to a solar power station, which is connected to both the grid and solar power sources. I want the solar power to be the primary charging source, with automatic switching to the grid if solar power is unavailable.

Thanks

 

[hwy17]

The smallest system that is pretty universally recommended around here is Will's hand truck build.

EG4 3k + Lifepower4 5kwh battery. It plugs into 120v, outputs 120v, and accepts solar input. It will do some kind of Solar-Utility-Battery or Solar-Battery-Utility mode like you're looking for. About $2000 without the solar panels.

It may not switch over in an outage fast enough to keep a computer powered on, but for refrigeration that's no problem if there's a blip.

There are ecoflow and products like that. But in the DIY community we don't usually think they're a very good value. Small batteries for the price.

 

[Mattb4]

Off grid AIO. Need battery for reliability. Loads will determine sizing of system. Also you could go route of SCC and inverter/charger since many of these incorporate UPS functionality. Image below is a setup if you run a critical load panel. The Transfer switch is not a requirement.

 

[protomech]

Ecoflow Delta 2 (and I suspect Ecoflow River 2 line) will do this. You can set a backup reserve % where grid will kick in; then battery above that is available for solar charging only.

You can easily set the % in the app, so in advance of severe weather you can quickly add additional energy.

I actually came to ask this very same question - do other manufacturers offer similar functionality in their app? (Oupes does not, wondering about Anker)

 

[Kremer]

The Bluetti products with selectable UPS modes will do this. I’m running part of my house on an AC300 right now in this way with it set to PV priority UPS mode.

 

[seneysolar]

Almost any inverter charger with built in transfer switch can do this using AC priority. Just size for your needs. 1000w is plenty for a fridge. AC would need more power, preferred a LF inverter with good surge capability.

1000 Watt Pure Sine Inverter Charger - ETL Listed Conforms to UL458 / CSA Standards

1000 Watt Pure Sine Inverter Charger - ETL Certified Conforms to UL458 Standards

www.aimscorp.net

Some inexpensive AGM batteries are best suited for standby use.

AGM 12V 200Ah Deep Cycle Battery Heavy Duty ETA End of May

This 12V AGM battery is a heavy duty, deep cycle battery ideal for back-up power, golf carts and stored power applications. Affordable without compromising quality, this battery will provide power for years. This heavy duty rechargeable battery is made of AGM lead lead dioxide technology. The...

www.aimscorp.net

There are endless options from here to charge your battery with solar. As simple a a single panel and charge controller.