Nowadays numerous efforts are being made to promote the use of clen energy technologies. Energy geostructures allow for satisfying part of the building needs, providing heating/cooling by exchanging heat with the ground. In this work, a case study of a private building located in Italy with thermally activated piled foundation is presented. Experimental tests were carried to study the thermo mechanical properties of the soil site. Referring to available data of the building design and the experimental results, a 3D Finite Element model of the foundation was reconstructed and its thermo mechanical behavior during normal operating conditions has been analyzed.

A series of numerical experiments based on the Tsinghua Science Museum project were conducted to investigate the thermal behavior of energy pile group under annual, imbalanced load and the influence of pile spacing. There is a linear relationship between the flow temperature and the total heat exchange, so the proportion of thermal load borne by energy piles in a hybrid system can be determined. The pile spacing affects the magnitude of variation in heat exchange fluid temperature by influencing the degree of heat accumulation in soil.

A numerical process is presented and used to model the behaviour of an energy pile group system, taking account of COP variation according to soil temperature variation. The effect of seepage velocities and pile proximity generating heat cluster are studied on a realistic case in order to obtain quantitative data on COP variation over month of heat pump uses.

• Numerical investigation on the use of the building’s foundations as Energy Geo-Structure using a detached residential building with nearly Zero Energy Building characteristics as a case study. • The use of the foundation bed and the foundation pile elements as Energy Geo-Structures have been investigated and compared.

Energy screw piles combines the agile construction of screw piles with renewable shallow geothermal energy. Moreover, the screw piles can be filled with Phase change materials (PCM) to provide latent thermal storage. This work explores a novel underground heat exchange system that combines traditional energy screw piles with thermal storage screw piles filled with PCM (TSP). Simulations are undertaken with numerical modelling, providing insights on the operation of short energy piles groups and how PCM improves the thermal storage. The PCM improves the system performance for cooling while deteriorates it for heating, and the TSP stores up to 190 MJ/m3.

* Energy quay walls are an innovative type of energy geostructures capable to exchange heat with both soil and open water. * A finit element numerical model is presented to analyze the thermal performance of an energy quay wall test site installed near Delft (NL). * The numerical simulations effectively reproduce the gained thermal power as well as the induced temperature changes into the soil.

A recently proposed approach for cooling underground tunnel substations using tunnel airflow is investigated across four different cities around the world, finding up to 21 kW of available cooling per pipe loop over 20 years of operation. The temperature of the air flowing in the tunnels is crucial to the amount of cooling that can be provided, while the farfield ground temperature is also impactful, to a lesser extent. The incorporated pipe length is varied, finding a logarithmic relationship to the amount of cooling energy provided, concluding that a leg length of 150-200 m is most resource efficient.