Devon County Council is pressing ahead with a wider trial of dimming streetlights across the county.

The plan was agreed by councillors on December 11 and will start in the next financial year, from April 2025.

The trial effects residential streetlights in urban and rural areas, with the lighting of main roads to remain the same as it is now.

The policy, aimed at reducing energy costs and promoting dark skies, follows a small-scale pilot with 550 streetlights in Abbotskersell, Holcombe Rogus, Kingskersewell and Sidmouth, trialling earlier switch-off times and additional dimming, using upgraded technology which allows adjustments to be made remotely to around 50 per cent of Devon’s 80,000 streetlights.

The low number of responses to the changes has convinced the council to press ahead with a wider trial, which sees the dimming of streetights in the evening, later in Exeter, earlier in market towns such as Tavistock and Okehampton and later in rural areas.

The trial will apply the following:

- In Exeter, residential streetlights will be dimmed to 40 per cent output from 9:30pm-12:30am, before being switched off from 12:30am until 5:30am, and returning to 40 per cent output from 5:30am-6:30am.

- In market towns, they will be dimmed to 40 per cent output from 8:30pm-midnight, then switched off from midnight to 5:30am, with 40 per cent output from 5:30am-6:30am.

- Rural areas will see residential streetlights dimmed to 40 per cent from 7pm to midnight, switched off from midnight to 5:30am, with 40 per cent output again from 5:30am-6:30am.

Councillor Stuart Hughes, Devon County Council Cabinet member for highway management, said: “Over the last decade, our streetlighting team has focused on reducing energy usage while keeping the public safe. I'd like to thank them for their efforts in this area. They've done a sterling job but there's an opportunity to do more, for further carbon reductions and cost savings.

“The installation of our central management system will enable us to make adjustments to light dimming and timings during this extended trial. It’s quite interesting that in Sidmouth, which was one of those areas chosen for the six-week trial earlier this year, I only received two responses which speaks volumes.”

The County Council has worked closely with Devon and Cornwall Police throughout the small-scale trial earlier this year, and in developing the proposed 12-month trial. If Police raise any safety concerns over the lighting levels during the trial, they can be reviewed and they have the potential to be altered via the Council’s Central Management System.

The findings of the trial will be reviewed in 2026 for further consideration by the county council’s Cabinet.

Devon County Council first introduced part-night streetlighting in residential areas in 2009 and its current policy has been in place since 2019.

Devon's streetlights used around 12million kWh of electricity in 2023/24, compared to around 31million kWh in 2015/16, which equates to an annual £6 million saving, with savings attributed to both the dimming policy and replacement of conventional bulbs with LEDs.