Solar Car Park Lighting: Do Solar Lights Work in Winter?

The short answer

Standalone solar lighting columns can light a UK car park, but only if they are sized for December, not June. Winter output is a fraction of summer output while the nights are more than twice as long, so a column that looks fine on a summer demonstration can run flat in winter. Where a cable route and a supply already exist, or a solar carport is planned anyway, fitting LED lighting to the site supply is usually the simpler design. Which is right depends on the site, and the arithmetic below shows how to test a supplier's claim.

Why December decides it

PVGIS (the European Commission's solar tool, SARAH3 data, 14% system losses) gives the monthly output of 1 kWp of panel tilted 60° and facing south. The darkness hours are astronomical day length at the solstices, ignoring twilight.

Assumptions for the last column, all stated so they can be checked: a 30 W LED fitting at full output from dusk to dawn, 80% battery round-trip efficiency, December average daily output from PVGIS, and no allowance for snow cover, shading or battery ageing. Real products reduce the load by dimming after a set hour or by using presence sensors, which is a legitimate design choice, but it means the light is not at full output all night. Ask for the dimming schedule in writing.

What the table means for a buyer

A single 30 W fitting needs a panel of several hundred watts in December before any margin for a run of dull days, and the requirement rises as you go north. A column that carries a much smaller panel must either dim, run a shorter night, or carry a larger battery that never fully recharges in winter. None of this makes solar lighting a poor choice for a remote or cable-free car park. It means the supplier should show the December calculation for your latitude, not a summer one.

When standalone solar columns make sense

• The car park has no supply and the cost of cabling to the columns is high.
• The lighting is temporary or the site is remote.
• The lighting requirement is modest and a dimming profile is acceptable.

Where the site already has a supply, or the car park will carry a canopy and EV charging, grid-fed LED fittings are usually simpler to specify and to guarantee. See EV charging canopies for how lighting and charging can share a structure.

Can a solar carport power the car park lights?

Not directly at night. A solar carport array generates during the day and car park lighting runs after dark, so without a battery the night load is met by the site supply. What the array does is cut the site's daytime import or earn export payments, which offsets the cost of the lighting over time. Fittings can be mounted on the underside of the canopy, which can avoid separate columns, but the canopy's height is limited if you are using the England permitted-development route (4 metres to the highest part; see solar carport design). The solar carports guide covers the structure and the car park solar panels guide covers the array.

Lighting levels and standards

Outdoor car park lighting is designed against British Standards, in particular BS 5489-1 (design of road lighting) and BS EN 12464-2 (lighting of outdoor work places). The level required depends on how the car park is used, the traffic and the local crime risk, so the figure belongs on a lighting designer's calculation for your site, not in a rule of thumb. Ask any supplier, solar or grid-fed, for ground-level calculations to the relevant standard.

What to ask a supplier

1. The December energy balance for your latitude, with the panel size, battery size and load stated.
2. The dimming or presence-sensing schedule, in writing.
3. Autonomy: how many consecutive dull days the battery covers, and the battery chemistry and its temperature limits.
4. Lighting calculations at ground level for your layout, to the standard your designer specifies.
5. Maintenance: panel cleaning, battery replacement interval and warranty terms.

Frequently asked questions

Sources and last checked

Last checked 20 October 2026.

• PVGIS v5.3 (SARAH3), European Commission JRC: monthly output for 1 kWp, 60 degrees, south, 14% losses; run 20 October 2026 (data saved in research/pvgis-2026-10-20.json)
• Day length: standard astronomical formula at the 21 December and 21 June solstices (declination 23.44 degrees), ignoring refraction and twilight
• legislation.gov.uk: GPDO 2015 Schedule 2 Part 14 Class OA (4 metre limit)
• BSI: BS 5489-1 and BS EN 12464-2 (standards named only; levels are not quoted here)

Related reading: an EV charging canopy · what to specify in a carport · capital allowances on a solar carport.