C-DRONE GUIDE · 3 AUGUST 2026
Public lighting audit by night drone: outages, over-lighting, dark corridors, price
Public lighting is often a town's biggest electricity bill and one of its least-known assets: incomplete inventories, failed lanterns reported only through complaints, areas over-lit for decades. A night drone flight photographs the lighting actually produced — not the theoretical plan: dark points, colour disparities between generations of lamps, halos spilling onto façades and natural areas. For a local authority engaged in LED renovation, partial switch-off or a dark ecological corridor, it delivers an objective baseline, then a before/after check. Method, night-flight rules and prices.
Published on 3 August 2026, reviewed on 3 August 2026 — regulations in force as of August 2026.
What a night map reveals
The drone overflies the town at night and assembles a georeferenced mosaic of night images. It shows at a glance: failed light points (lamp, cable, drifting timer), colour-temperature gaps betraying the generations of lamps still in service, over-lit areas (car parks, roundabouts, business parks) and light trespass hitting façades, gardens and watercourses instead of the road. Cross-checked against the energy syndicate's inventory, the map exposes gaps between the theoretical and the actual stock.
Measuring light pollution by drone is an established research topic: Bouroussis and Topalis (National Technical University of Athens) published in 2020 in the Journal of Quantitative Spectroscopy and Radiative Transfer the concept of a drone-gonio-photometer, an instrumented drone characterising outdoor lighting installations and their contribution to light pollution (see the study on Google Scholar). The stakes keep growing: the global study by Kyba et al. in Science Advances (2017) measured a steady satellite-observed increase in artificially lit surfaces (see the study).
Dark corridors and compliance: beyond savings
Since the French decree of 27 December 2018 on light nuisance, outdoor lighting installations are regulated: beam orientation, share of light emitted above the horizontal, colour temperatures, switch-off windows for certain uses. The night map helps document compliance — and target the legacy luminaires to treat first.
It also serves dark-corridor policies: preserving unlit continuity for nocturnal wildlife along watercourses and woodland edges. The night flight shows precisely where light spills onto these ecological corridors — a natural companion to the thermal mapping of urban heat islands, the other big municipal environmental survey by drone. Finally, a second pass after works (LED renovation, dimming, partial switch-off) objectifies the result, with figures, for the council and residents. For the mechanical inspection of the masts themselves, see our guide on high-mast lighting inspection.
Night flying: a specific but workable framework
Flying a professional drone at night is possible in France but follows its own rules: aircraft lighting, reinforced preparation and, depending on zone and scenario, specific formalities — our guide night drone flights: what the law says covers the essentials. In built-up areas the mission is prepared with the same rigour as a daytime flight over a populated zone, with administrative lead time built into the schedule.
Technically, current sensors photograph a lit street scene very adequately without additional light; flights typically run in early night, once the whole stock is on, in dry weather. An average town is covered in one to three nights depending on area and flight plan.
Deliverables and 2026 prices
The typical deliverable includes the georeferenced night mosaic, an annotated light-point layer (out, colour, spill) usable in the municipal GIS, and a summary note ranking anomalies. Orders of magnitude in 2026 (excl. VAT):
- Village or district (one night of flying, map + note): €900 to €1,800.
- Average town (two to three nights, full GIS layer): €1,800 to €4,500.
- Post-works check (partial re-flight, before/after comparison): €600 to €1,200.
The service sits within our thermal imaging and aerial mapping offer; request a quote stating population, area to cover and whether an up-to-date lighting inventory exists.
Frequently asked questions
Can a drone really fly at night over a town?
Yes, professional night flying is workable in France within a specific framework (aircraft lighting, reinforced preparation, formalities depending on the zone). Over built-up areas, allow several working days for the administrative declaration in the project schedule.
Does the lighting have to be switched off during the audit?
No — the opposite: the flight covers the lighting switched on, to photograph what it actually produces. A second pass during a partial switch-off window can however verify that the switch-off is effective where scheduled.