Battery, plug-in or USB? Holiday lights for small spaces compared

In a small home the question is rarely "how bright?" and mostly "where does the cord go?". A light string on a bookshelf, a wreath on the front door or a branch in a vase may be nowhere near a socket, and a cord across the floor is a trip hazard in a room you walk through twenty times a day. The power source decides where lights can go.

The three power sources

(Open the diagram full size)

• Battery. A small battery box sits at one end of the string. No cord to the wall, so the lights can go on a shelf, in a jar, on a wreath or on a door. Many sets have a built-in timer. The trade-off: batteries run down, and you will be changing or recharging them through the season.
• Plug-in. Mains-powered strings give steady power for longer runs, a window frame or a tree. The cord has to reach a socket along walls and furniture edges, not across a walkway, and a plug-in timer makes switching off automatic.
• USB. The string plugs into a USB adapter or a power bank. Useful for short runs near a desk, a bed or a socket, or for something you want to move around with a power bank.

Side by side

	Battery	Plug-in	USB
Where it works	anywhere: shelves, wreaths, doors, jars	near a socket, longer runs	near an adapter or with a power bank
Cord to the wall	none	yes	yes, or none with a power bank
Runtime	until the batteries run down	as long as it is on	as long as it is on; power bank until empty
Timer	often built in	add a plug-in timer	some have one built in
Typical small-home use	bookshelf, door wreath, table centrepiece	window, tree	headboard, desk, small shelf
Main drawback	batteries to replace or recharge	the cord route	short reach, adapter in the socket

Brightness and battery life depend on the set, not on the type, so read the box. A string that only lasts a few hours on one set of batteries will cost more over a season than its price suggests.

Safety that applies to all three

• Tested lights. The US Consumer Product Safety Commission advises using only lights tested for safety by a nationally recognised testing laboratory ^[1]. In Europe, look for the equivalent independent test mark on the box.
• Check every set, new or old, for broken or cracked sockets, frayed or bare wires and loose connections ^[1]. Damaged sets go in the bin.
• Outdoor only if labelled. Outdoor lights must be labelled as certified for outdoor use, and the CPSC advises plugging them only into GFCI-protected outlets ^[1].
• Extension cords must be rated for the intended use and in good condition ^[1].
• Keep the tree watered and away from heat. According to the NFPA, a heat source too close to the tree causes nearly one in four Christmas tree fires, and a dried-out tree can reach flashover in under a minute ^[2].
• Off when you go to bed or leave. A timer or a built-in timer setting makes that automatic.
• If you mix in candles, keep them on a stable, heat-resistant surface out of reach of children and pets, away from trees, decorations and curtains, and put them out before leaving the room ^[1]. Battery candles avoid the question.

Timers

A timer is the simplest safety upgrade in this article. For plug-in strings, a plug-in timer between the socket and the plug switches the lights on in the evening and off at bedtime. Many battery sets have a built-in timer that runs the lights for a few hours each evening and repeats daily; the box says how long. With USB lights, a power bank simply runs out, which is a crude timer of its own.

Which one for which spot

• Front door wreath, bookshelf, table: battery.
• Window or tree: plug-in, with a cord route planned before you hang anything.
• Bedside or desk: USB, from an adapter you already have in that socket.

For hanging lights without drilling, tension rods are one option; how they work and what they hold is in our guide to tension rods.