How to Prepare a House for a Utility Power Shutoff

Why this matters

A public safety power shutoff (PSPS) is a planned outage: the utility de-energizes lines on purpose during high wind and dry conditions so its equipment cannot start a wildfire. Unlike a storm outage, it comes with warning, often a day or more, and it can last from several hours to several days, because the utility has to patrol every de-energized line before restoring it. That warning is the whole opportunity. The houses that get through a shutoff badly are the ones where nobody used it: an oxygen concentrator with a dead battery, a portable generator plugged into a dryer outlet, a garage door nobody knows how to open by hand, a family on a well with no water stored. A field service shop that knows its customers can use the same warning to prevent most of that.

How shutoff warnings usually arrive

The pattern is best developed in California, where the state utility commission directs utilities to notify affected customers in stages: a first notice where conditions allow about two to three days ahead, a second about one to two days ahead, and a final one shortly before de-energization, with extra contact for customers enrolled as medical baseline. Utilities in several other western states now run shutoff programs with their own notice rules, and the timing in practice depends on how fast the weather forecast firms up. Treat the first notice as the start of the clock, and know that some shutoffs arrive with much less.

Notices come by circuit or address, not by city. Customers can usually look up whether their address is in the shutoff area on the utility's outage map.

Step 1: Find the people who depend on electricity to stay safe

Start with powered medical devices: oxygen concentrators, ventilators, home dialysis, powered wheelchairs, infusion pumps, CPAP and refrigerated medication. For each, the household needs to know the battery runtime, whether there is a backup (charged spare batteries, a backup oxygen cylinder, a plan to go to a family member's house outside the area, or a community resource center the utility opens), and whether they are enrolled in the utility's medical program.

Why first. Everything else in a shutoff is inconvenience. This is the part that is not. And it has the longest lead time: battery spares, oxygen deliveries and transport are not arranged the morning of.

What breaks if skipped. A concentrator user discovers on hour two that the backup cylinder is nearly empty and the supplier cannot deliver before the shutoff. The shop's own shutoffs in homes with medical equipment have their own card; see the References.

Step 2: Set up backup power only through approved transfer equipment

A portable or standby generator may feed house circuits only through a transfer switch or a listed interlock kit for that specific panel, installed to the electrical code as adopted (NEC Article 702 covers optional standby systems, and requires transfer equipment for them). Never through a double-male cord into a dryer or range receptacle, and never by plugging into any outlet.

Why. Backfeeding through an outlet energizes the house wiring and, unless the main breaker is open, the utility's transformer, which steps the generator's voltage up to distribution voltage on lines a lineworker believes are dead. It also has no overcurrent protection on the cord. See related: Generators, Backfeed and the Lineworker.

Placement. Run a portable generator outdoors only, at least 20 feet from doors, windows and vents per CDC guidance, with exhaust pointed away from the house, and with a working battery-backed carbon monoxide alarm inside. Never in a garage with the door open.

What breaks if skipped. Carbon monoxide poisoning from a generator near the house is one of the most common causes of death and injury during outages.

For the shop. If a customer with a portable generator has no transfer equipment, the safe pre-shutoff service is extension cords run from the generator to specific appliances, sized for the load, or a transfer switch or interlock installed by an electrician before the shutoff, not a workaround.

Step 3: Plan the refrigerator and freezer

Keep doors closed. USDA guidance: a closed refrigerator keeps food safe for about 4 hours; a full freezer holds about 48 hours, a half-full one about 24. Before the shutoff, turn both to their coldest settings, freeze water bottles to fill freezer space, and put an appliance thermometer in each.

Why. The thermometer is what makes a decision possible afterward. Perishable food held above 40 F for more than 2 hours is discarded under the same guidance, and without a reading the household is guessing.

Step 4: Know how to open the garage door by hand

Show the household the emergency release on the opener trolley. Pull it with the door closed. If the door must be opened, lift it from the bottom, and if it feels much heavier than usual, stop: a broken spring means the door's full weight is unsupported, and it can drop.

Why. Many households have never opened their garage door by hand, and a car or a wheelchair-accessible vehicle can be trapped inside during an evacuation that coincides with the shutoff.

What breaks if skipped. Releasing the trolley with the door open lets an unbalanced door free-fall.

Step 5: Store water if the house is on a well

A well pump does not run without power, and neither does a booster pump or a septic system's effluent pump or aerobic treatment unit. Store at least 1 gallon of drinking water per person per day (CDC and Ready.gov guidance) for the expected length of the shutoff plus a day, and fill containers or a tub for flushing.

Why. Households on municipal water usually keep water through a shutoff, so they are not the ones who think about it. Well households are, and they often discover the dependency only when the faucet stops.

Septic note. With an effluent pump or treatment unit out, the household should cut water use to the minimum; the tank fills with nowhere to go.

Step 6: Get the rest of the house ready

Charge phones, battery packs, power tools and any electric vehicle. Pre-cool or pre-heat the house. Find flashlights rather than candles. Know how to open an electric gate manually. Turn off and unplug sensitive electronics, or put them on surge protection, ahead of restoration. Never use a gas range, oven or outdoor grill to heat the house.

Step 7: Restore in order when power comes back

When the utility restores power, turn the generator off and switch the transfer equipment back to utility before or as the utility returns, per the transfer switch's instructions. Then bring loads back a few at a time.

This step carries its own hazards. Re-energizing the house is where a fault introduced during the outage shows itself.

• Generator. Do not refuel a hot generator; let it cool. Switch the transfer equipment fully back so the generator and utility are never connected together.
• Well pump. Watch the pressure tank come up and look for leaks at the tank and well head before leaving it running.
• HVAC and heat pumps. Follow the equipment's restart guidance; many manufacturers recommend letting the system sit powered with the thermostat off for a short time before calling for compressor operation. Check for tripped breakers before resetting anything twice.
• Garage door. Re-engage the trolley, then run the door and confirm the photo eyes and the reversal function work before anyone stands in the opening.
• Food. Read the thermometers before deciding what to keep.

Worked example: a shop's outreach before a shutoff

A residential HVAC and plumbing shop gets word Tuesday morning that the utility has issued a first shutoff notice covering several circuits in its service area, with de-energization expected Thursday morning.

Pulling the list. The office filters the shop's customer records by the ZIP codes and street ranges named on the utility's map: 86 active customers. Flags already on file:

• 7 with a medical device noted on the account
• 22 on a private well
• 11 with a generator on record: 4 standby with transfer switches, 7 portable with no transfer equipment noted

Two of the 7 medical households are also among the 7 portable-generator households. So the priority list is 7 plus 7 minus the 2 counted twice, or 12 households.

The calls. At about 8 minutes a call, 12 calls is about 96 minutes of office time Tuesday afternoon. Everyone else gets a text message Tuesday with the short version of steps 2 to 7, and the 22 well households get a line about water storage added.

OFFICE:   Hi, it's Dana from the shop. The utility
          says your street is in Thursday's shutoff.
          Is the oxygen machine running on the wall?
CUSTOMER: Yes, and the little backup tank.
OFFICE:   How full is the backup tank, roughly?
CUSTOMER: I don't know. Maybe half.
OFFICE:   Worth calling your oxygen company today to
          ask how many hours half gives you. They need
          a day to deliver. Do you still have the
          generator we saw last spring?
CUSTOMER: Yes, my son plugs it into the dryer plug.
OFFICE:   Please don't do that this time. It can feed
          power back down the street lines. We can run
          cords from it to the machine and the fridge,
          or get an electrician out tomorrow for a
          proper switch. Which works for you?

The follow-through. Of the 7 portable-generator households, 3 book an electrician for an interlock or transfer switch Wednesday through the shop's electrical partner, and 4 take a tech visit to set up correctly sized cords and a CO alarm. The medical households get a note on the account to call again Wednesday afternoon.

What changes the answer. If the first notice arrives with less than a day to go, there is no time for transfer equipment; the calls shrink to medical backup, generator placement away from the house, and "do not plug into the house". If the shutoff area includes a customer who is alone and unable to manage a generator or a manual garage door, the right call may be to the household's family contact, if one is on file and the customer has said the shop may use it.

References

• California Public Utilities Commission PSPS notification guidelines, and your own utility's shutoff program
• NFPA 70, National Electrical Code, Article 702 (optional standby systems), as adopted by your jurisdiction
• CDC guidance on generator use and carbon monoxide; USDA food safety guidance during power outages; Ready.gov water storage
• See related: Planning a Shutoff in a Home With Medical Equipment
• See related: Generators, Backfeed and the Lineworker