Seamless battery advice

[5olarmanChuck]

I've had a 12kW SolarEdge system since 2018. Right now, my utility does a sweet 1:1 buyback for my extra power.
But in a few years (after 10 years of operation), that changes to basically a half price buyback.

So, I'm thinking of adding a battery system down the road, but I'm clueless. How big a battery would I need for a 12kW system?
When exactly does the battery kick in? Is it scheduled, or just anytime I try to draw from the grid? also, is the transfer totally seamless, or does the power flicker when it switches over?
need advice from the home battery pros about this, TIA

 

[Maribel_Mayde]

For a 12 kW array, most folks go with around 20–30 kWh of storage if you want decent overnight coverage. Smaller if you’re just shaving peaks. The battery kicks in automatically when production drops or during an outage. With hybrid inverters, the switch is nearly instant like you might see a one-second blip if you’re watching the lights.

 

[King_Troad]

Batteries don’t usually “kick in” unless you set them to. You can schedule when to charge or discharge, or just let the inverter handle it automatically based on grid status and TOU pricing. SolarEdge works well with their Energy Bank or LG Chem units if you want plug-and-play control.

 

[h4ckberry]

@5olarmanChuck It's all about your usage pattern, not just array size, chuck. Since your 1:1 net metering is ending, the goal shifts from production to self consumption. Look at your usage profile to see exactly how many kWh you pull from the grid between sunset and sunrise. now, that's the number you're actually trying to cover

 

[83tim allen]

That's a very common scenario now that NEM agreements are ending.
try to check the inverter. you will need to replace your current SolarEdge inverter with a newer SolarEdge Energy Hub to integrate the battery (or other compatible brands). Factor that into your upgrade cost.

 

[Alan]

For a system your size, people usually start with something in the 10 to 20kWh range if the goal is daily cycling and some backup. The battery normally kicks in based on either a schedule or a priority setting inside the app, so you get to decide how aggressive it should be. Modern inverters usually keep the switchover smooth enough that you do not notice it. Are you planning more for grid savings or for outage protection?