If your Seattle house has natural gas and you want heat through a storm that keeps the power off for days, get a standby generator. A home battery fits if you already have solar (or are adding it) and mostly want the fridge, lights and internet to ride through shorter outages quietly. And if all you really need is the furnace and the fridge, you may not need either one. A portable generator on a transfer switch does that, and it's a much smaller project.
Before you decide, write down three things: which rooms and appliances you can't go without for a week, whether you have gas at the house, and whether solar is on the roof or in the plan. Those three answers make most of the decision for you.
How long Seattle power outages last
Trees are one of the biggest causes of outages around here. A branch comes down on a line, the power goes out, and a crew puts it back.
The one to plan for is the windstorm that keeps you dark for most of a week, like November 2024. After that storm PSE took close to a week to get 99% of the affected customers back. That's the outage where the house goes cold, and that's where these options split.
A natural gas standby generator runs as long as gas service is on. A battery runs until it's empty, and without solar it can't refill itself during an outage. Solar helps, but storm days aren't sunny ones, and winter here is short on sun to begin with.
What a battery vs. a generator keeps running
A battery keeps the fridge, lights and internet going. It won't keep the house warm for days. A heat pump or an electric furnace pulls far more than a fridge and a router, and that's the load that empties a battery first.
If the well pump or A/C has to run on the battery, say so up front. That changes the setup, and it can change how many batteries you need.
A standby generator runs what it's sized for, for as long as the gas holds, heat included. We size it to what you want running: the whole house, or just the essentials. The trade-offs are upkeep and noise. It needs a service once a year (oil, filter, load test, battery check), and it sits outside, near your neighbors.
The option most people skip is a portable generator through a manual transfer switch and an inlet on the outside of the house. A portable runs the fridge and the furnace fan fine. The catch is that you start it, fuel it and keep it maintained yourself. The usual way portables fail is neglect: no servicing, stale fuel, and you find out in the middle of the storm when everyone else is trying to buy one. Run it outside, away from windows and doors, and never in the garage.
Transfer switches, either way
Don't plug a generator into a dryer outlet. It can energize the utility lines and hurt a line worker down the street. You need a transfer switch, and we install it. City Light requires one for a standby generator, installed by a licensed electrician and approved by City Light. Opening your main breaker and feeding the house instead is not a workaround either. City Light calls it illegal and unsafe.
A standby switches over by itself in a few seconds. With a portable, you flip the switch.
A battery has its own switch too, and City Light has to sign off before it's turned on. A grid-connected battery goes through their interconnection process first, with an inspection before permission to operate. That's paperwork and time to plan for, separate from the battery itself.
Want both? Say so before the battery goes in. Not every battery will take a generator, and the ones that do need the right controller from the start. It's a lot easier to pick the right one up front than to find out during an outage that the generator can't recharge the battery.
What to expect on a generator walkthrough
We start with your list: the whole house, or essentials like the furnace, fridge and network gear. Then we look at your panel and where the generator could sit. That decides between a portable hookup with a manual transfer switch and a standby unit with an automatic one.
A standby goes outside on a level spot, away from windows, doors and vents, as close to the gas meter and panel as practical. We check that on the site visit. If the panel needs changes to take the generator, that's part of the same conversation (more on that on our panel upgrade page).
Every install needs an electrical permit, and standby units need a gas permit too. We handle both, coordinate the inspections and the gas connection, and then show you how the switchover works, so the first time you see it isn't in the dark.
If you're leaning toward a battery, bring the same list to whoever is quoting it. The questions are the same: what has to stay on, for how long, and whether you have solar to refill it. If heat is on that list and the answer to solar is no, a generator is usually the better fit for a Seattle winter.
Have questions about your project? Contact us for a free estimate.