Battery or Generator for Power Outages in Colorado?

Home Battery vs. Generator for Colorado Outages

If you need to run a whole house through a week-long outage and have a steady fuel supply, a generator is hard to beat. If your outages are hours to a few days, you want silence and no fuel, and you’d like the equipment to cut your bill the other 360 days a year, a battery charged by solar is the better fit. Many foothills and mountain homes are best served by both. We install batteries, not generators, and we’ll tell you when a generator is the better answer.

Updated Sep 23, 2026

What Colorado outages actually look like now

The old outage was a summer thunderstorm or a blizzard knocking out power for a few hours. The new one is planned. In December 2025, Xcel Energy cut power to about 50,000 customers in Boulder, Clear Creek, Jefferson, Larimer and Weld counties to reduce wildfire risk, and in March 2026 it shut off about 18,000 more. Those outages ran 24 to 72 hours or longer.

The length of your likely outage is the most important input. A battery sized for a four-hour evening outage won’t carry a three-day shutoff unless solar recharges it. A generator carries a three-day shutoff as long as fuel holds out.

Where generators are the better tool

A properly sized standby generator on natural gas, or on a large propane tank, can run a whole house, including electric heat, for as long as fuel lasts. For long outages in cloudy or snowy weather, when solar can’t recharge a battery, that endurance is the generator’s real advantage.

Up front, a generator also buys a lot of power for the money, especially for big electric loads like resistance heat, an electric range and a well pump running together. If your priority is simply never being without power for a long outage, a generator deserves a serious look.

Where batteries win

A battery switches over automatically in a fraction of a second, so clocks, routers and medical devices don’t reboot. It’s silent, has no exhaust, needs no fuel deliveries and doesn’t need weekly exercise runs or oil changes. With solar, it recharges itself every sunny day of a multi-day shutoff.

Most importantly, a battery works on ordinary days too. On Xcel’s time-of-use rates, a battery can cover your 5–9 pm on-peak window with solar stored earlier in the day, and some utilities pay for letting them draw on it during grid peaks. A generator only earns its keep during outages.

Fuel is the hidden question

Natural gas generators depend on the gas utility staying up, which it usually does, but it’s not guaranteed. Propane generators depend on the size of your tank and whether a delivery truck can reach you in a storm or an evacuation zone. Portable gasoline generators need cans refilled, and running one near a window or garage is a real carbon-monoxide danger.

Solar’s fuel is the sun, which in a Colorado winter means short days and the occasional snow-covered array. That’s why battery backup plans should be built around your essential loads, not the whole house at full blast, and around a realistic recharge from your specific array.

Cost: compare the whole picture

Our battery prices are about $19,000 for a first Powerwall 3, about $17,000 for the first 10 kWh of Enphase, and $15,500 for the first ~9 kWh of Sigenergy. As of September 2026, Colorado’s 10% income-tax credit on residential batteries still applies for tax year 2026, and some utilities offer battery incentives. Verify current terms before counting on either.

Get generator quotes from licensed installers for your house; prices vary with size, fuel and how much of the home it serves. Then compare the full picture: up-front cost, fuel, maintenance, noise and what each does on the days the grid is up. A battery that trims your bill every evening pays back in a way a generator doesn’t.

When to have both

Some homes should have both: rural properties on a well, mountain homes at the end of a long feeder line, households with medical equipment that can’t fail. The battery handles every short outage silently and the first day or two of a long one. The generator is the backstop for a week of snow and clouds.

Not every battery and generator combination is designed to work together, and how they connect matters for safety. If you have or plan a generator, tell us during design and we’ll confirm what the battery system you choose supports.

FAQ

Questions we hear

How long can a home battery run my house during an outage?

It depends on the battery’s capacity and what you run. A 13.5 kWh battery powering essentials like the fridge, furnace blower, lights and Wi-Fi can often last through a night and beyond; running central air or electric heat drains it far faster. Our blackout runtime calculator estimates it for your loads.

Can solar recharge my battery during a multi-day shutoff?

Yes, on sunny days, if the system is designed for backup. That’s the main advantage over a generator in a long outage. In cloudy or snowy stretches, recharge is limited, so plan around essential loads.

Is a generator cheaper than a battery?

Up front, often yes, per kilowatt of backup. But a generator needs fuel and maintenance and does nothing on normal days, while a battery can lower your bill daily on time-of-use rates. Compare total cost over the years you’ll own it.

Are batteries safer than generators?

Batteries produce no exhaust, so there’s no carbon-monoxide risk. The batteries we install are listed to UL safety standards and installed to code. Generators are safe when professionally installed and vented, but portable units run too close to the house are a well-known cause of carbon-monoxide deaths.

Should I get a battery if I already have a generator?

Possibly. A battery covers short outages silently and adds daily savings, while your generator stays as the long-outage backstop. We’ll confirm how the two can work together safely before recommending it.