GEOLAB Project FROSPER: FROst heaving soils-Solar Panel foundations interaction in cold European Regions: an experimental study

The objective of the proposed project is to investigate the resilience of solar panels foundations in cold climates. The efficiency of solar panels is overall better in cold climates, when the direct sunlight is available, due to the lower temperature-induced dispersion. For this reason, large solar fields tend to be installed in cold regions, such as northern Europe or Canada. A solar field with e.g., 10 MW, requires a great number of solar panels (~6000) whose foundations are generally steel piles driven into the soil down to a depth of 2÷5 m below the ground surface. In the cold regions, the shallow layers of soil are periodically subjected to freezing thus to the frost-heaving phenomena. The latter can increase the risk of uplift failure mechanism of the pile foundation compromising the exercise of the entire solar panel row.
This project aims to investigate the interaction between saturated soils and solar panel foundations under frozen conditions in scaled centrifuge models. The steel piles will be at first driven into the saturated soil sample, then a set of the freezing-thawing cycles will be reproduced in the centrifuge. Possible practical interventions to reduce the soil frost-heaving effects will also be explored, as the use of protective insulating mantel at the ground surface all around the head of the pile.
This project will represent a breakthrough in the understanding of the solar panel foundations behaviour, allowing a deeper insight into possible uplift failure mechanisms. The motivation of the study lies in the reduction of the costs and in the resilience improvement of critical infrastructures for the generation of energy in the EU territories.