In ground-source heat-pump systems, the heat exchange rate is influenced by various design and operational parameters that condition the thermal performance of the heat pump and the running costs during exploitation. One less-studied area is the relationship between the pumping costs in a given system and the heat exchange rate. This work analyzes the investment and operating costs of representative borehole heat-exchanger configurations with varying circulating flow rate by means of a combination of analytical formulas and case study simulations to allow a precise quantification of the capital and operational costs in typical scenario. As a conclusion, an optimal flow rate minimizing either of both costs can be determined. Furthermore, it is concluded that in terms of operating costs, there is an operational pumping rate above which performance of geothermal systems is energetically strongly penalized.

This paper presents a structured strategy for integrating the Sustainable Development Goals (SDGs) into university courses by linking them to competencies and learning outcomes. The proposed methodology, based on fuzzy logic, evaluates the degree of alignment between teaching activities and selected SDGs through matrices that connect competencies with assessment activities and expected learning outcomes, improving the gap regarding the inclusion of the SDGs and their articulation in terms of competencies. The approach was applied to two subjects from the Master’s Degree in Renewable Energy and Energy Efficiency at the Distance University of Madrid: “Electricity Market” and “Wind Energy”. In both cases, the learning outcomes were redesigned, and the activities were adjusted to ensure meaningful incorporation of sustainability principles into the curriculum. The method enables quantification of each activity’s contribution to the SDGs and supports a critical review of curriculum design to ensure coherent integration. The results indicate that project-based activities show the highest alignment with the SDGs, particularly with Goals 7, and 12, which achieve an average rating of 0.7 (high). The developed tool provides a practical and replicable solution for sustainability-oriented curriculum planning and can be adapted to other disciplines and educational programs.

A research project was developed in Spain to undertake some studies on the geothermal use of pile foundations (PITERM PROJECT). The experiment consists of a specifically designed, constructed and fully monitored geothermal precast pile driven at Polytechnic University of Valencia. An important distinctive feature of the developed pile was the fact that it was assembled from two identical sections connected with a specific joint, developed by Rodio-Kronsa. This allows the installation of much longer precast piles into the ground. The pile is under two types of loads: mechanical and thermal. The mechanical load was applied by means of a mechanical frame anchored to the ground and three additional anchors used to induce an active compressive force. The thermal load was produced by means of a thermal rig able to inject heat or extract heat from the pile at any desired programable heat injection/extraction rate. One of the features of this precast pile is its geometry, similar to a single U borehole heat exchanger (BHE) which is not common in thermoactive piles, usually equipped with probes attached to the armatures. In our study, we have characterized the thermal behaviour of the precast pile experimentally and simulated its temperature response by means of a TRNSYS model. This article describes part of a test series carried out where the mechanical and thermal behaviour of a pile subjected to thermal and mechanical loads simulating a real pile in a building was studied. Therefore, this publication has only focused on the thermal performance of the pile and its thermal modelling by computer. From this model, the thermal parameters of the soil–pile system have been extracted and compared with those of a single standard single U BHE. In essence, our assessment points to a quite similar thermal behaviour of the studied precast pile compared to a conventional single U borehole heat exchanger of the same length and equivalent diameter, while the installation costs of such elements would be substantially lower due to its double, structural and thermal, function.

La introducción de nuevas metodologías en la docencia universitaria facilita el proceso de aprendizaje de los alumnos a la vez que ayudan a mejorar su motivación. Por otro lado, la introducción de nuevas herramientas en el proceso de evaluación enriquece y clarifica la realimentación ofrecida a los alumnos mientras que la evaluación entre pares les hace partícipes en la misma. En este artículo se refleja la experiencia de aplicación en la asignatura optativa de Geotermia de 4 Curso del Grado en Ingeniería de la Energía de nuevas metodologías en la docencia, en concreto la clase inversa y las charlas coloquio realizadas en formato seminario por un profesional experto en la materia; y también de nuevas metodologías en la evaluación de la asignatura, mediante la introducción de rúbricas y evaluación entre pares. Todas estas nuevas herramientas docentes han permitido que los alumnos adquieran un conocimiento más práctico de la asignatura y que se haya podido dedicar más tiempo a la resolución de casos reales de forma presencial en el aula porque los alumnos ya acudían a ella con un bagaje teórico previo. Finalmente, en el artículo se analizan los resultados académicos obtenidos después de la introducción de estos instrumentos innovadores en comparación con años anteriores, la opinión de los alumnos obtenida mediante una encuesta respecto a esta nueva metodología docente y nuevo proceso de evaluación mediante rúbricas y entre pares, y el rol y experiencia de los docentes durante la aplicación de estas nuevas metodologías docentes y de evaluación.

Implementación de los Objetivos de Desarrollo Sostenible (ODS) en la asignatura optativa Geotermia de 4º Curso del Grado en Ingeniería de la Energía