Passive Geothermal System for Road Ice Prevention: Design, Implementation and Pilot Validation

Abstract

The formation of ice on roads is one of the leading causes of winter traffic accidents, resulting in significant social and economic costs. Conventional maintenance techniques, such as salting and mechanical clearance, are costly, environmentally harmful, and not always effective. This paper presents the design, implementation, and pilot validation of a passive geothermal anti-icing system tested at a dedicated experimental facility in Spain. The system consists of copper vertical heat exchangers (1 m depth), a thermal diffusion grid beneath the asphalt layer, and an IoT-based monitoring network using LoRaWAN sensors to capture real-time temperature data at three depths. During the monitoring period, the pilot system showed an increase in subsurface temperature compared to the control section, resulting in a lower likelihood of ice formation on the pavement surface. These findings demonstrate that passive geothermal systems can help improve road safety under winter conditions while reducing energy demand and the use of chemical agents. Future research will focus on optimizing system design, integrating deeper heat exchangers, and assessing large-scale economic feasibility.