On the Exploitation of Ground Heat Using Transportation Infrastructure.

The use of shallow geothermal energy systems that employ heat-exchange loops within trenches and boreholes is well established. The use of civil engineering structures that are in contact with the ground (geo-structures) to replace the more conventional heat-exchange methods is creating great interest in many countries. Bearing piles have been used for this purpose since the mid-1980s, retaining walls since the late-1990s and the use of tunnels has been explored since the early-2000s. With regards to transportation infrastructure shallow geothermal may be used to provide renewable heating and cooling to the infrastructure itself or adjacent users, or even to enhance safety by providing e.g. heat to de-ice bridges, station platforms, airport run-ways and the like. This paper presents an overview of the potential application energy geo-structures in transportation infrastructure through case studies and numerical simulations, and then goes on to discuss some of the issues associated with the potential use of geo-structures for heat exchange, in terms of construction, thermal operation and the impact of heating and cooling on the geo-structure. [ABSTRACT FROM AUTHOR]