The time-of-use job
Xcel’s on-peak price is about 2.7 times its off-peak price, and the window — 5 to 9 pm on non-holiday weekdays — is exactly when solar production fades. A battery that charges from your panels in the afternoon and discharges into that window avoids the most expensive power on your bill.
Whether that savings justifies roughly $15,500–$19,000 for a first battery depends on how much of your usage lands in the peak. Many Denver households will see a long payback on time-of-use savings alone, and we’ll say so.
Permits: SolarAPP+ and exterior batteries
When a battery is added as part of a qualifying rooftop solar project, Denver’s SolarAPP+ quick permit can include it. A battery installed on an exterior wall also needs a zoning permit, so we often place Denver batteries in the garage or basement when code and clearances allow.
Adding a battery to existing solar, with no new panels, typically goes through standard permitting.
Incentives as of September 2026
Colorado’s 10% income-tax credit for home batteries applies through tax year 2026, and batteries are exempt from state sales tax. Xcel’s Renewable Battery Connect program has paid an upfront incentive per kilowatt of battery capacity in exchange for letting Xcel draw on the battery during a limited number of events each year; amounts have stepped down over time.
Denver has offered battery rebates through its climate programs in the past, but their status has changed often. Verify current terms for each before counting them.
FAQ
Questions we hear
Is a battery worth it in Denver if we rarely lose power?
It can be, but mainly as a time-of-use tool. If a large share of your usage falls between 5 and 9 pm on weekdays, a battery can trim that cost; if not, the payback may be long enough that we would advise against it.
Can my battery go on the outside of my house in Denver?
Often, yes, but an exterior battery needs a zoning permit in addition to the electrical permit. Garage installs avoid that extra step when clearances allow.
Does Xcel pay me to let it use my battery?
Xcel’s Renewable Battery Connect program has offered an upfront incentive in exchange for limited event dispatch. Amounts and enrollment windows change, so check current terms before signing up.
How long would a battery run my Denver house in an outage?
It depends on what you back up. A single 13.5 kWh Powerwall 3 can often carry a refrigerator, furnace fan, lights and internet overnight, but not central air or an EV charger for long. Our blackout-runtime calculator lets you pick loads and see estimates.