I'm considering setting up a grid tie solar system with net metering through PSO in Oklahoma. Their diagram shows the flow from solar panels to an inverter, then to a lockable AC disconnect, a distributed generation meter, and finally the service panel and utility meter. I really want to implement this setup but also need a way to disconnect from the grid in case of outages. My initial thought was to go with a simple and cost-effective solution: Solar -> Inverter (specifically, the Growatt 11.4kW Grid-Tie Inverter) -> new subpanel with an interlock kit -> lockable AC disconnect, and so on.
However, I've read that solar systems require power to operate, so I was wondering if I could switch the new subpanel's interlock to off-grid mode during grid outages. Would connecting a backup battery to this subpanel allow me to utilize some solar power when the grid goes down?
I'm planning to use 28 Canadian Solar 450 watt topCon panels (totaling around 12.6kW), along with Tigo TS4-A-O optimizers and the Growatt inverter. I'm curious if this setup sounds okay or if I should consider alternate options.
3 Answers
I've got the same Growatt 11.4 inverter and went a different path with a generator as backup instead of batteries. Just a heads up — the listed batteries for that inverter can get pretty costly! Also, check which authority approves your installation—different places have different rules for grid connection.
You might want to think about using a hybrid inverter with battery backup instead. It could save you some hassle in terms of switching between grid and off-grid modes during an outage!
Just a heads-up: any decent inverter will typically have an auto disconnect feature, so your solar system won’t operate during power outages unless you have batteries. The cost difference for switching to the Gridboss and Flexboss systems might be significant—around three grand more even with tax credits—but it could be worth it for reliable backup. Just make sure your hybrid inverter has the necessary outputs for backup power, as some need extra components that might be expensive.
Thanks for the heads up! I'm trying to balance cost and functionality, so I'll dig into those details more. Sounds like there’s a lot to consider if I want to maintain some power during outages!
That does sound like an easier route! I know the hybrid option might be pricier upfront, but it simplifies everything. Just a thought!