Europe’s transport infrastructure is on the verge of a major transformation, thanks to the innovative Liaison project.

This initiative aims to integrate sustainability into road networks by introducing groundbreaking solutions like the photovoltaic guardrail.

Designed to enhance road safety while generating renewable energy, this cutting-edge solar technology could play a crucial role in Europe’s decarbonisation efforts.

Photovoltaic guardrail: Transforming highways into renewable energy sources

Motorists travelling along the highway from Turin to Trieste, near Erbusco, Italy, may soon witness history in the making.

What appears to be an ordinary guardrail is, in fact, an advanced energy-producing system. Integrated with ultra-thin solar panels, this pioneering photovoltaic guardrail is expected to generate approximately 25 megawatt-hours of electricity per kilometre annually.

This output is sufficient to power around 20 households, showcasing its potential as a sustainable energy solution.

Unlocking the potential of road infrastructure

With over 136,700 kilometres of roads across Europe, this technology could significantly contribute to the continent’s renewable energy capacity.

The concept originated from recognising the untapped potential of roadside infrastructure. By utilising vast stretches of guardrails to capture solar energy, roads can become active participants in clean energy production.

Dual purpose: Safety and sustainability

Developed by Tecnalia and Vita International, the solar guardrail combines energy generation with enhanced road safety.

Unlike conventional barriers, it includes a specialised sheet designed to protect motorcyclists while housing the solar panels.

Additionally, the generated power can support essential roadside operations, such as traffic signals, street lighting, and tunnel ventilation, reducing reliance on the traditional power grid and cutting operational costs for road operators.

Real-world testing and future deployment

A 100-metre test installation is scheduled to be deployed by the end of the year. This trial will assess the guardrail’s performance across different seasons and conditions, ensuring durability and efficiency.

The initiative falls under the Liaison project, an EU-funded effort promoting sustainability and circularity in transport infrastructure.

One of the major technical hurdles is the impact of shadows from passing vehicles on solar panel efficiency.

To counteract this, developers are exploring advanced power electronics that isolate shaded panels without affecting the rest of the system.

Additionally, innovative panel designs featuring series-parallel connection schemes help mitigate performance losses.

Another key consideration is durability. While the photovoltaic guardrail is engineered to withstand standard road impacts, individual solar panels may need periodic replacements following accidents.

To address this, the design prioritises easy maintenance, incorporating protective coatings to minimise damage and extend lifespan.

Advancing the circular economy in road infrastructure

The photovoltaic guardrail aligns with broader European sustainability efforts. In addition to generating renewable energy, the Liaison project is advancing eco-friendly road construction methods.

This includes geopolymer-based concrete slabs and 3D-printed beams from recycled materials, reducing reliance on carbon-intensive materials like cement and steel.

The road ahead: Challenges and opportunities

Despite its potential, widespread adoption of photovoltaic guardrails requires a shift in mindset among policymakers and infrastructure stakeholders.

The road construction sector has long been resistant to change, making large-scale implementation a challenge.

However, with growing environmental concerns and the increasing viability of renewable energy solutions, there is a strong case for integrating this technology into future road development projects.

The photovoltaic guardrail represents a significant step toward a more sustainable and energy-efficient transport system.

By leveraging existing road infrastructure for solar energy generation, this innovation can play a crucial role in reducing emissions and enhancing the resilience of transport networks.

As real-world testing progresses, the hope is that policymakers and industry leaders will recognise the immense benefits and accelerate the adoption of this game-changing technology.