Power Options for Tiny House Smart Locks: Battery, 12 V, or AC

Tiny homes swing between shore power, solar, and nothing at all. Your lock should not care.

Option A — Primary Batteries

• Pros: simple, isolated from house power; lithium AAs handle cold well.
• Cons: replacement schedule; watch for cheap cells.
• Tip: label install date; test under load before trips.

Option B — 12 V DC Feed (Solar/House)

• Fuse at source (0.5–1 A). Run to a buck converter if the lock needs 5 V.
• Place buck near the door; set to ~5.1 V; ferrules + strain relief.
• Idle draw typically 0.2–0.5 W → ~5–12 Wh/day. Budget it with the calculator.

Option C — AC with Backup

• Use a small DC supply on a protected circuit; add a UPS or local backup cells.
• Surge protection and proper grounding if you're grid-tied.

Best Practices

• Inline quick-disconnect inside the door for serviceability.
• Neutral-cure silicone at pass-throughs; IP-rated glands; drip loops.
• Kill noisy features (loud tones, bright LEDs) to save power and neighbors.

Related Reading

• Cold/Heat Micro-Adjustments — Seasonal power strategy.
• Serviceability in Tight Tiny-House Interiors — Quick-disconnects and wiring.
• Quarterly Maintenance Ritual — Battery checks.