Solar batteries & NEM 3.0: are they worth it?

What net billing changed

Under full 1:1 net metering, the grid effectively was your battery: you exported midday surplus at the full retail rate and pulled it back at night for the same price. Under NEM 3.0 (and similar net-billing tariffs), exports pay only about 5-8¢/kWh while you still buy grid power at 30¢+. Suddenly, exporting your surplus is a bad trade, and storing it to use yourself is a great one.Full explanation of net metering vs. net billing.

How a battery changes the math

A battery stores your midday surplus and releases it in the evening peak, so those units offset power you'd otherwise buy at the full retail rate instead of earning the low export rate. The value of each stored unit is roughly the gap between your retail rate and the export rate, which under NEM 3.0 is large. In high-rate California, that gap can be 20¢+ per kWh, which is what makes storage attractive there specifically.

When a battery is worth it

• You're on a net-billing tariff (NEM 3.0, or similar in AZ, NV, and a growing list) where exports pay far below retail.
• Your retail rate is high and time-of-use, with an expensive evening peak the battery can cover.
• You have meaningful evening/night usage, AC, EV charging, cooking, for the stored energy to displace.
• You value backup power during outages, which a battery provides and panels alone do not.

When it's a weaker case

• You still have full 1:1 net metering. The grid already banks your surplus at full value; a battery adds cost for little extra savings.
• Low electricity rates. A small retail-to-export gap means each stored unit saves little.
• Mostly daytime usage. If you already consume your solar as it's generated, there's less surplus to store.

The honest trade-off

A battery typically adds a large chunk to the system cost and, on pure payback, often recovers that over a long horizon, sometimes close to its warrantied life. In net-billing states it can be the difference between a mediocre and a good return; in full-net-metering states it's usually a comfort/backup purchase more than a financial one. Size the panels to your home first, then decide on storage based on your tariff and evening usage. Our calculator gives you the panels-only baseline to build on.