Renewables
New assessment framework calculates solar potential of highways
Researchers in China have developed a model to evaluate photovoltaic generation potential along highway networks, estimating an annual output of 182 TWh.
Key points
- Researchers at Tongji University created an irradiance-terrain-road network coupling model for highway solar assessment.
- The framework evaluates roadside areas, structural zones at tunnels, and service-area rooftops.
- China's 185,000 km highway network could generate 182 TWh annually, according to the study published in Next Energy.
What happened
A research team at Tongji University has created a new assessment framework to calculate the photovoltaic generation potential of highway systems. According to pv magazine, the methodology integrates solar irradiance, terrain characteristics, and road distribution, moving beyond traditional assessments that focus solely on available land.
The corresponding author, Xiaojun Shen, explained that the model categorizes usable spaces into roadside areas, structural zones at tunnel entrances and exits, and service-area rooftops. The researchers applied the framework to China's 185,000 km highway network using NASA Power irradiance data for 2025 and spatial tools like ArcGIS and OpenCV.
The study estimated that the highway network could yield an annual solar generation of 182 TWh, which represents roughly 1.85 percent of the country's total electricity consumption for 2025. Roadside areas provided the largest share of this potential, followed by service-area buildings.
What comes next
Despite the significant generation potential, the researchers highlighted three main challenges facing large-scale deployment. These include high installation costs and extended payback periods, potential conflicts with roadside ecology and traffic safety, and a lack of coordinated regional planning for fragmented demonstration projects.
Future work by the research team will focus on examining the techno-economic performance of solar and storage configurations at service areas. They also intend to incorporate traffic safety constraints into the framework to develop practical deployment guidelines.
Why it matters
As nations across the globe seek innovative ways to expand renewable energy generation without competing for arable land, infrastructure-integrated solar models offer a compelling pathway. The approach demonstrates how linear infrastructure can contribute to national electricity supply while addressing localized grid challenges through tailored operation schemes.
For emerging economies and energy investors, evaluating non-traditional spaces for renewable deployment is increasingly relevant. According to World Bank data from 2024, global electricity use per person stands at 3,708.5 kWh, with worldwide access to electricity at 91.9 percent. Frameworks that optimize existing transport corridors for power generation provide valuable lessons for infrastructure planning in regions striving to scale up clean energy capacity efficiently.
Original reporting
This article draws on the following reports. Read them in full on the publishers’ sites.
Context from CEII
Renewables are the fastest-growing part of the world’s energy system. The COP28 goal is to triple capacity by 2030, and solar mini-grids are the fastest route to power for millions of people without electricity.
28.4% of electricity in China was renewable in 2021Countries in this story
Written by the CEII Desk, the Centre’s automated newsroom, from the reporting credited above and CEII’s own data. Facts are attributed to their sources; the publishers have not reviewed this article. Spotted an error? Tell our editors.
