Compensation & bill · battery decision

Are solar batteries worth it.

Updated May 16, 2026. Sources verified the same day. We rerun this guide every quarter against the EIA residential rate releases.

A 13.5 kWh home battery costs $14,000–$17,000installed in most US markets. The proposal sitting on your table probably shows it earning back the cost two different ways at the same time: bill savings from time-of-use arbitrage, and resilience value from backup power during outages. Both numbers are real. You only get one of them. Pretending you get both is how an installer bundles a $15K product into a payback table where it's really contributing $4K of value.

Here's the framework that separates the two — and the decision matrix that drops out of it.

Savings product vs resilience product

A battery as a savings product charges from your panels during the day (or from cheap off-peak grid power overnight) and discharges during expensive peak hours. The savings = (peak rate − off-peak rate) × kWh moved per cycle × cycles per year, minus round-trip efficiency losses (~10–15%) and degradation. In a market with flat residential rates around 17¢/kWh¹ and full retail net metering, this number is small — your grid connection already moves kWh across hours at full retail rate. Adding a physical battery on top is mostly cycling hardware on the same spread the utility meter already gives you.

A battery as a resilience productkeeps a portion of your home running during a grid outage. The value isn't in $/kWh arbitrage — it's in keeping the refrigerator, the freezer, a few lights, and maybe a well pump or sump pump running through a multi-day storm. That value depends on outage frequency and what going dark would actually cost you (lost food, hotel nights, sump backup, medical equipment).

The math gets done twice — once for each purpose. They don't add cleanly, because a battery sized for a 3-day outage isn't the same configuration as a battery cycled daily for TOU arbitrage, and cycling for arbitrage uses up the cycles you'd need for backup. A salesperson stacking both numbers in a single payback row is selling one product as two.

The continuous-load reality

A typical 13.5 kWh battery has a 5–7 kW continuous output. Your home's peak draw (air conditioner + refrigerator + dryer + oven + electronics) regularly tops 8–12 kW. Without a critical-loads subpanel that limits backup to a few essential circuits, the battery cannot run a whole house through an outage; it trips its own breaker. Most installs include a critical-loads panel for exactly this reason. If your proposal doesn't — or if the salesperson hand-waves about “whole-home backup” — ask for the wiring diagram and the continuous-load spec sheet.

The decision matrix

The trap most articles miss

Net-metering policy changes the answer more than rate design does. In a state with full retail net metering, the grid isyour battery — every kWh you export earns a credit at retail rate, and every kWh you import draws against that credit. A physical battery adds little because the meter already moves your generation across the day. In a state that's switched to net billing (exports valued at wholesale or avoided-cost), the spread between retail import and wholesale export can be 10–15¢/kWh — and a battery that time-shifts your own generation to your own load captures that spread. The same physical battery is worth two different things in two different states. Check which policy your utility uses before agreeing the payback math is real.

What “worth it” actually means

A battery isn't a financial product. It's a hardware purchase that has some financial return and some non-financial return. The honest framing: if you would buy a generator to handle outages, a battery is often the better purchase in the same dollar range, and the bill-savings component is a bonus, not the case for the purchase. If you would not buy a generator — outages are rare, you have no critical loads — a battery is hard to justify on bill savings alone in most markets.

The math your specific situation calls for — your rate plan, your outage history, your load profile — runs in the battery calculator, which separates the savings number from the resilience number so you can see what each one is actually contributing.

1. 1. EIA Electric Power Monthly, Table 5.6.A — Average Price of Electricity to Ultimate Customers by End-Use Sector. February 2026 residential average: 17.65 ¢/kWh, +7.4% year over year vs February 2025. 10-year residential rate trend: ~2–3% per year. Released April 23, 2026. Verified 2026-05-16. eia.gov/electricity/monthly ↩

Next: Run your battery's payback math →