Energizer 38511 review: a night light that switches on by itself the moment the power fails

This is a research-based review, based on manufacturer specs and published data. We do not test products. Specs come from Jasco's product page for the Energizer 4-in-1 Rechargeable Power Failure Light Sensing LED Night Light (38511), checked November 1, 2026. Lighting safety guidance comes from the CDC and the National Fire Protection Association (NFPA).

The most dangerous moment of a night outage is often the first one. The house goes black, people get up to find a flashlight, and someone misses a stair. A power failure light solves that specific problem: it sits in an outlet as an ordinary night light, charges its own battery and switches on by itself when the outlet loses power.

Energizer's 38511, made and sold by Jasco under license, adds a light sensor so it works as a dusk-to-dawn night light day to day, and it lifts out of the wall to become a small flashlight. Jasco's page is light on numbers, which this review flags rather than fills in.

Who should buy it

• Households with stairs, long hallways or small children, where an instant light prevents falls.
• Older adults who get up at night and should not have to find a flashlight in the dark.
• Anyone who wants light in several places at once without leaving lanterns running.
• Renters: it plugs in and needs no installation.

Who should skip it

• Anyone who needs to light a room for hours. With no published lumens or runtime, plan on a lantern such as the Energizer WeatheReady or Goal Zero Lighthouse 600 for that.
• People who want a replaceable battery. Jasco says the battery is non-replaceable, so the light is retired when the battery fades.
• Bedrooms where any glow at night is unwelcome. It is a night light first.

Strengths

• Automatic. It turns on during a power outage with no button to find.
• Always charged. The built-in battery charges while the light is plugged in, so it is ready whenever the power fails.
• Four jobs. Night light, power failure light, tabletop light and handheld flashlight, per Jasco.
• Light sensor. On at dusk, off at dawn, so it is not burning all day.
• Packs flat. The fold-up plug lets you carry it as a flashlight without prongs catching on things.

Drawbacks

• No published output or runtime. Jasco's page lists neither lumens nor battery runtime, so you cannot plan around it.
• Non-replaceable battery. When it stops holding a charge, the whole light goes.
• Small light. It is designed as a night light and pocket flashlight, not a room light.
• Outlet placement. It lights the area near the outlet, usually near the floor.

How it compares

Three other ways to have light the moment the grid fails. Figures are from each manufacturer's page, checked November 1, 2026.

Using it in a long outage

Where to put them

• At the top and bottom of every staircase.
• In the hallway between bedrooms and the bathroom.
• In the kitchen, near the drawer where the flashlights and lanterns live.
• Near the breaker panel or the door to the garage, so someone can find the panel and the generator cord in the dark.

Use outlets that are not controlled by a wall switch. A light in a switched outlet only charges when the switch is on, and could be flat when you need it.

The first ten minutes

1. 01Let the power failure lights do their job: they show the hallways and stairs.
2. 02Lift the nearest one off the wall and use it to reach the main flashlights and lanterns.
3. 03Put it back in the outlet afterwards so it is in a known place, even though it will not charge until power returns.
4. 04Switch on lanterns for the rooms people will use, and leave the night lights to cover paths.

In a long outage

Once the grid is down for days, these lights run down and stay down until power returns, since they recharge only from the outlet. Their value is the first night and the moment of each new outage in an area with rolling blackouts or repeated storm damage. For multi-day light, use lanterns that run on stored batteries or recharge from solar, and see our emergency lights guide.