Solar-powered road studs are reshaping the future of highway lighting. With the industry still playing catch-up on tackling the climate crisis, it is about time too
By Ralph Bates
The climate emergency, we all know, threatens our shared future and is already having a tangible impact on our quality of life and the environment. For those working in highways and transport, the challenge is clear. We must do our bit to shift the dial towards net zero, and we must do it quickly.
That means focusing on the things that really move the needle, the materials and assets that together account for around 40% of the total carbon emissions of the highways sector.
Highway authorities across the UK are already grappling with how to reduce both whole-life and operational carbon, while at the same time facing unprecedented pressure on their budgets. Few assets sit more squarely at the intersection of carbon, cost and route safety than street lighting.
RETHINKING THE ROLE OF STREET LIGHTING
Street lighting is no longer about whether to light, but why, where and how to light. Over the past decade, many of us have noticed a shift in our own neighbourhoods, with a move away from lighting everything, everywhere, all at once, towards a more targeted and thoughtful approach. In essence, the ILP’s mantra of ‘right light, right place, right time’.
And this is for good reason. Let’s face it, every streetlight carries a cost far beyond the initial capital investment. There is the embedded carbon in the column and the lantern and there’s the ongoing energy consumption, plus a lifetime of maintenance. All of this stacks up financially and environmentally.
Many of the lights being replaced today were designed more than 40 years ago yet are still being unconsciously swapped out like-for-like. In the context of net zero commitments and spiralling energy costs, that simply isn’t good enough. We can, and we must do better. In the UK, local authorities spend over £1bn every year on street lighting and the electricity to power them.
Collectively, street lighting emits more than one million tonnes of CO2 annually. At the same time, highway authorities face two big, unavoidable challenges: achieving net zero and reducing costs. So, it’s really encouraging that the government, together with highway authorities throughout the UK, is now asking fundamental questions. Are we over-lighting?
Are we lighting places that don’t actually need to be lit? Are outdated designs and ‘revert to type’ solutions locking us into unnecessary carbon and cost for decades to come? According to findings so far from the ADEPT Live Labs 2 programme, around 20% of streetlights across the UK are unnecessary or underperforming.
Replacing them with passive or low energy alternatives such as solar-powered illuminated in-road studs could significantly contribute to an annual saving of around £300m and cut 200,000 tonnes of CO2. That’s not a marginal gain, that’s transformational.
LESSONS FROM LIVE LABS 2
Over the past three years, we’ve had the privilege of working with East Riding of Yorkshire Council on its ground-breaking decarbonising street lighting project. This, as many ILP members will be aware, has been an innovative project funded through ADEPT’s Live Labs 2 initiative, and part of a £30m Department for Transport programme aimed at decarbonising the local highway network.
Our role has been focused on introducing solar-powered road studs as part of a much wider examination of the future of lighting highways, local roads and paths. The question wasn’t ‘what can we replace existing lighting with?’, but ‘what assets do we actually need on our future networks, and how can they be decarbonised across their entire lifecycle?’.
Therefore, along with enhanced road markings, more than 5,000 solar-powered illuminated road studs have been installed as part of this project along an eight-kilometre stretch of the A164 between the Humber Bridge and Beverley and on the A1079 on the approach to Hull.
The results have been compelling – and do check out what Karl has to say on this – not just in terms of carbon and cost reduction, but also safety, and public acceptance. What is clear to me is that solar-powered road studs are changing how drivers are guided in low-light conditions and after dark.
Powered entirely off grid, they have no energy costs, operate automatically from dusk to dawn and can store enough energy to run for up to 240 hours without sunlight. Crucially, they provide continuous, high-visibility guidance even in torrential rain and thick fog conditions, when conventional lighting often struggles. Frontline practitioners involved in Live Labs 2 have been quick to point out just how inefficient some traditional street lighting is. Trees blocking light require expensive pruning; poor column placement makes lighting ineffective; pedestrian and shared-use routes often disappear under dense tree canopies.
Moreover, every single night, thousands of streetlights burn energy (and budgets) regardless of whether anyone is there to benefit. Removing unnecessary columns and replacing them with targeted, solar-powered alternatives cuts maintenance, slashes energy use and will improve safety by putting light exactly where it is needed.
From East Riding of Yorkshire to East Ayrshire, the decision to adopt solar-powered, ground-level lighting represents a significant step towards a transport environment that is safer, greener and smarter all year round.
CONCLUSION: TIME FOR ACTION
The highways sector is under no illusion about the scale of the challenge ahead. But the good news is that some of the solutions already exist.
By rethinking what lighting is really for and embracing targeted, solar-powered alternatives, we can cut carbon, reduce costs and improve safety. The lights are on. The camera is rolling. Now it’s time for action.
Ralph Bates is business director at Clearview Intelligence UK
Image: solar road studs in Milton Keynes, courtesy of Clearview Intelligence UK
This is an abridged version of the article that appears in the April edition of Lighting Journal. To read the full article, simply click on the page-turner to your right.
