Energy piles in bulgarian construction practice

Bulgaria offers favourable conditions for the implementation of energy piles due to its stable geothermal gradient, the presence of groundwater, and characteristic geotechnical conditions in urbanized areas such as Sofia. The typical local soil layers facilitate efficient heat exchange, while the growing demand for Nearly Zero Energy Buildings, supported by EU directives and intensive construction activity, creates a strong foundation for widespread adoption. Energy piles serve a dual function – load transfer and heat exchange with the ground via embedded pipes – and their integration into geotechnical structures requires minimal additional investment. This study presents initial steps toward adapting the technology in Bulgaria through analytical solutions (using the EPFL Thermo-Pile software), focused on evaluating mechanical behaviour under thermal cycles. The paper emphasizes the need for standardization, increased awareness, and demonstration projects to support the successful implementation of sustainable geotechnical solutions in local construction practice.