Battery backup for security cameras and alarms

Home security splits cleanly in an outage. The alarm panel is a regulated product with a battery inside it and a published runtime. The camera system is an unregulated one with no battery anywhere, made of parts whose draw the manufacturer does publish, feeding a recorder that depends on a router nobody thinks of as a security device. Sizing this is mostly a matter of adding up numbers that already exist. We have not tested any of these products, and the Amazon links above are affiliate links, disclosed at the top of this page.

The alarm panel is the part already covered

NFPA 72's household chapter sets the requirement, and the text NFPA publishes for section 29.9.3 states it directly. Household fire and carbon monoxide alarm systems must have "two independent power sources consisting of a primary source that uses commercial light and power and a secondary source that consists of a rechargeable battery," and that secondary source "shall be capable of operating the household alarm system for at least 24 hours in the normal condition, followed by 4 minutes of fire alarm or 12 hours of carbon monoxide alarm."

The commercial equivalent is longer on the alarm side and identical on the standby side. NFPA's own guide to fire alarm power supplies states that batteries "need to be sized so that they can provide power to the entire fire alarm system for 24 hours in standby and 5 minutes in alarm," rising to 15 minutes for an emergency voice alarm communication system, and that where a generator is present the batteries "only need to provide a capacity for 4 hours instead of the 24 hours in standby."

Consumer security systems are not fire alarms and are not bound by that clause, but the makers publish comparable figures anyway. Ring states that its Alarm Base Station is "armed with a powerful siren, plus built-in backup battery to help keep you secure for up to 24 hours if you lose power," and lists an "internal rechargeable Lithium Ion Backup Battery which lasts up to 24 hours."

Twenty four hours is the recurring number, and it is worth reading as a design target rather than a promise about your storm. If your outages run to three days, the panel's own battery covers the first third of one.

What a camera system draws

Reolink is unusually forthcoming here: it publishes a support article listing power consumption by model group for its entire PoE camera range. The figures, read August 19, 2026:

| Model group | Published consumption |

|---|---|

| B400, D400, B800, D800, RLC-420, RLC-520 | under 8 W |

| RLC-410, RLC-422, RLC-511, RLC-522 | under 10 W |

| RLC-510A through RLC-1240A, plus Duo PoE, Duo 2 PoE, E1 Outdoor PoE, TrackMix PoE, Doorbell PoE | under 12 W |

| Duo 3 PoE, Elite XPro PoE | under 15 W |

| RLC-423 | under 20 W |

| RLC-823 series, Duo Floodlight PoE | under 24 W |

Reolink attaches the caveat that makes these usable: "The consumption is affected by the status of infrared lights, spotlights, master chips, and sensors, etc." So the published number is a ceiling that a camera reaches at night with its infrared array lit, not what it draws in daylight. A camera system is one of the few household loads that gets heavier after dark, which is also when you want it working.

Two other pieces of the system publish their own figures. Reolink's RLN8-410 recorder lists power consumption of "<10W (Without HDD&PoE)" with a DC 48V to 53V supply and eight PoE ports rated 25 W each. Western Digital's WD Purple product brief lists average power requirements across its surveillance drive family of 5.3 W read/write and 4.7 W idle at the top capacity, down to 3.8 W and 3.2 W at the bottom, with standby and sleep at 0.4 W or less.

Add those and the whole recording system becomes a single number. Six cameras in the under 12 W group, one recorder and one drive is 72 plus under 10 plus about 5.3, or roughly 87 W at published ceilings. What is not published anywhere is the loss in the ethernet cable between the recorder and the camera, which is real and which grows with run length. Treat the totals as an outer bound on the equipment and an underestimate on the installation.

Runtime arithmetic

Rated capacity divided by load. These use each unit's rated Wh rather than usable Wh and ignore inverter losses, the low-voltage cutoff and the station's own self-consumption, so real runtime is lower.

| Unit | Rated capacity | 4 cameras, 63 W | 6 cameras, 87 W | 8 cameras, 111 W |

|---|---|---|---|---|

| BLUETTI Apex 300 | 2,764.8 Wh | 43.7 h | 31.7 h | 24.8 h |

| Anker SOLIX F3800 Plus | 3,840 Wh | 60.7 h | 44.0 h | 34.5 h |

| EcoFlow DELTA Pro 3 | 4,096 Wh | 64.7 h | 46.9 h | 36.8 h |

| Jackery Explorer 5000 Plus | 5,040 Wh | 79.6 h | 57.7 h | 45.3 h |

| EcoFlow DELTA Pro Ultra | 6,144 Wh | 97.1 h | 70.4 h | 55.2 h |

The column headings are cameras in the under 12 W group with the recorder and one drive included. Swap in a floodlight model at under 24 W and each of those cameras counts double, which is the single largest lever in the table. Six floodlight cameras would be 144 W of cameras alone, and the smallest unit here would cover about 17 hours rather than 32.

The load nobody counts

A wired PoE system keeps recording locally with no internet at all, because the cameras, the ports and the recorder are one local network. What the internet buys you is remote viewing, cloud clips and notifications, which for most people is the entire reason the cameras exist. That makes the modem and router part of the security load rather than an unrelated line item, and it adds a small but genuinely always-on draw on top of the table above. Our work-from-home outage kit works that network gear out from published figures, and if your internet arrives by satellite the number is much larger, which our Starlink guide covers with SpaceX's own published averages.

Alarm makers solve the same problem in the opposite direction, by leaving the house network entirely. Ring's cellular backup, sold with a subscription and running on a third-party carrier, exists precisely because the panel's 24-hour battery is worthless if the router died in the first minute.

What to settle before you buy

Three things, in this order. Which camera models you actually have, because the published spread runs from under 8 W to under 24 W and a floodlight model is worth three of a small dome. Whether the recorder and the network gear share a location, since a single power station behind the rack is a much simpler installation than running cords across a house. And whether the panel is the thing you were worried about, in which case the code-required battery already covers the first day and the honest answer may be that you need nothing further.

If the camera system turns out to be one line on a longer list, the comparison that matters is between the plug-in units above and a wired system, which our plug-in backup guide and portable versus installed comparison both take up.

Every figure above is a published claim recorded with its source: camera and recorder figures from Reolink's own support article and RLN8-410 product page, drive figures from Western Digital's WD Purple product brief, the household secondary power requirement from the text NFPA publishes for NFPA 72 section 29.9.3, the commercial figures from NFPA's guide to fire alarm power supplies, and the panel battery claim from Ring's own product page, all read August 19, 2026. The runtime numbers are arithmetic on those claims under the assumptions stated, not measurements we made, and not a promise about your system.