Solar security lighting: a buying guide for UK properties

Solar powered security lights are lamps that charge from a small panel by day and switch on at night, usually when a motion sensor trips. They cost nothing to run and need no cable. For many UK properties they are the quickest way to make a dark corner feel watched.

Choosing well matters, though. A cheap light with a weak battery will fade by January, and a badly aimed one will annoy your neighbours. This guide explains what to look for, what the law says and how to place lights so they work.

What solar powered security lights do well

A solar light has three parts: a panel, a battery and a lamp with a sensor. The panel charges the battery in daylight. At night a passive infrared (PIR) sensor detects body heat and wakes the lamp when someone moves in view.

That design suits places with no mains supply, since it needs no cable. A field gate, a barn end, a long drive and a garden shed are typical. You can also put them in spots where digging a cable trench would cost more than the light.

Light is a deterrent because it removes darkness, and darkness is what thieves rely on. A sudden beam tells an intruder that someone may be watching. Moreover, it lets a camera record a clear image instead of a grey blur.

Our range of solar floodlights with PIR lighting covers farm yards, drives and outbuildings. For homes with no grid connection, see our page on security for rural off-grid homes.

Panel, battery and lamp: how to size a light

Sizing is where many buyers go wrong, because spec sheets flatter the product. A light that is bright for ten seconds but flat by midnight is no use. Three choices decide how well it performs.

The panel must be big enough to refill the battery after a night of use. A small panel on a big lamp never catches up in winter. As a result, the light dims or dies in the months you need it most.

The battery should hold several nights of use with no sun. Modern lights mostly use lithium cells. Battery University lists lithium iron phosphate (LFP) at 2,000 cycles and higher, ahead of other common lithium chemistries. Cycle life depends on how deeply you drain the cell and on temperature.

Cold matters too. Battery University notes that consumer lithium-ion cells cannot be charged below 0 degrees C without permanent damage. One LFP datasheet we read specifies charging from 0 degrees C, although datasheets differ and some units include heaters. Ask the maker how its battery behaves in a frost.

The lamp should suit the job, because a wide beam wastes power on a narrow gate. A wide-angle floodlight covers a yard, while a narrow spot suits a gate. Look for adjustable heads, so you can aim the beam after fitting.

How much winter sun do you get?

Sunlight is the real limit in the UK. PVGIS, the European Commission’s solar tool, gives average monthly sunlight on a flat surface for 2005 to 2023. In December, London receives about 20.7 kWh per square metre, Edinburgh 11.7 and Lerwick in Shetland 3.9. In June the same places receive 158.7, 139.7 and 136.3.

By our sums from PVGIS, December sunlight is about 13% of June in London, 8% in Edinburgh and 3% in Lerwick. A light that copes with a London winter may struggle in the Scottish islands. Therefore, size up the further north you go.

Cold air does help the panel itself. A panel makes more voltage when it is cold, according to University of Colorado Boulder teaching material. In the UK, though, the lack of light matters more than the cold.

Our article on whether solar CCTV cameras work in winter applies the same data to cameras. The logic carries over to lights. Position the panel facing open sky, away from trees and roof edges.

Sensors, modes and false triggers

PIR sensors vary a great deal, so test before you commit. Range, angle and sensitivity all differ, and wind-blown branches can set off a poorly aimed unit. Every false trigger drains the battery.

Look for a light with at least two modes. One mode gives a dim glow all night and a bright burst on motion. The other stays off until it sees movement. The first suits a drive, while the second suits a remote shed, where every watt counts.

Check whether the sensor and the panel can sit apart. For instance, a remote panel on a lead lets you place the lamp in the shade but the panel in the sun. That is a useful feature on north-facing walls.

Dusk-to-dawn lighting also has a place. West Yorkshire Police’s Horsewatch leaflet advises owners to fit dusk-to-dawn lighting at stables. For sites like that, a larger panel and battery are essential.

Where to fit lights for the best effect

Position decides whether a light deters or merely irritates, so plan it first. Start at the points a thief must pass: gates, doors, the corner of a barn and the front of a fuel store. Mount lamps high enough that nobody can reach them, yet low enough for the sensor to see a person.

Avoid pointing a sensor at a road or a path. Passing cars and walkers will trigger it all night, which wastes battery and annoys people. Instead, face the sensor across the approach, so a person walks through its field of view rather than straight at it.

Overlap matters too. If two lights cover the same gate, a thief who breaks one still faces the other. Similarly, a light that covers a camera’s view keeps the picture sharp when it matters.

Finally, test after dark. Walk the route you expect a thief to take and watch when each light wakes. Adjust the angle until the first light comes on before you reach the building, not after.

The law: light nuisance and your neighbours

Bright lights can upset neighbours, and the law notices. Section 79(1)(fb) of the Environmental Protection Act 1990 makes artificial light from premises a statutory nuisance if it is prejudicial to health or a nuisance. This applies in England and Wales.

According to gov.uk guidance for councils, a council that finds a statutory nuisance can serve an abatement notice. Security lights are named as a common cause. There are no set light levels, so councils weigh how often, how long and when the light shines, and where the property sits.

In practice, you avoid trouble by aiming lights down, shielding them and pointing them at your own land. A motion-triggered light is also less of a problem than one that burns all night. If your camera shares the same post, read our home CCTV rules guide for the privacy side.

Wired or solar? Choosing between them

Mains lights give constant power and can run for hours. In contrast, solar lights give freedom of placement. Many properties use both, with mains lights near the house and solar lights at the edges.

Our guide to solar CCTV versus mains-wired CCTV covers the same trade-off for cameras. In short, cabling costs rise fast with distance, while solar costs stay flat. The battery is the part to watch, and our piece on how long solar CCTV batteries last explains ageing and replacement.

An off-grid alarm with monitoring adds a siren and a mobile alert to a lit site. A light can scare off a thief, while an alarm tells you it happened.

A buying checklist

Use these questions to compare products:

• Does the panel suit the winter sun at your latitude?
• Does the battery use a long-life chemistry with a stated cycle count?
• Can the unit charge in frost, and what does the datasheet say?
• Can I adjust the sensor angle and range?
• Can I place the panel apart from the lamp?
• Is the lamp shielded so it lights my land and not my neighbour’s?

Local coverage and a survey

We supply and install solar lighting across England, Scotland and Wales. Our coverage includes solar CCTV installation in Leeds, solar CCTV installation in Bristol and solar CCTV installation in York. In those areas, Avon and Somerset Police has a Rural Crime Team, and North Yorkshire Police has a Rural Taskforce. West Yorkshire Police runs a Wildlife Crime Unit that also covers rural crime.

The right light depends on your site, your sun and your neighbours. Request a site survey through our web form. We will recommend a lighting plan and give you a fixed quote.