Pedro García-Regodeseves

Learning Analytics tools are employed to assess student engagement with the Virtual Campus in an undergraduate Fluid Mechanics course at university level in Spain. This is aimed at obtaining a diagnosis of the course problematics which include low attendance rates, poor performance on activity tests and exams and a high number of re-enrolments. A total amount of 67,902 records from the online platform are analyzed to understand activity trends and information distribution. Specific indicators like percentage gap are defined and correlated with evaluation data for deeper insights. Different profiles of students are identified as a function of the interaction level with the platform. Significant correlation has been found between the level of interaction and the academic results of the students. While proactive profiles exhibit remarkable performance rates, no low-activity profiles were capable of passing the course. The continuous evaluation was found neither correlated with the interaction nor with the final exam marks, so its redefinition is suggested as future work. It is also shown that the higher the average number of student enrolments, the lower the participation and performance in the course. No bias was observed with respect to the gender variable. Moreover, the daily analysis of the records has discovered overall trends about the students’ habits. Learning Analytics is demonstrated as a useful tool for the specified purpose. It is also proposed to evaluate the effectiveness of further actions for the improvement of the course in future academic years.

In the current context of the energy transition, Integrated Solar Combined Cycle (ISCC) power plants are an alternative that are able to reduce carbon emissions from combined cycle (CC) power plants. In addition, the coupling to an energy storage system based on molten salts benefits hybridization, allowing the energy surplus to be to stored to cover peaks in energy demand. Because it is a recent technology, the determination of the optimal injection points for the solar-generated steam into the combined cycle is a critical issue. In this work, a thermodynamic model of a hybrid natural gas and solar thermal CC power plant has been developed using Thermoflex to analyze the integration effects in terms of efficiency and power. For all the steam injection candidate positions, the effects of ‘power boosting’ and ‘fuel saving’ operation modes have been simulated, considering operation conditions that are compatible with the useful range of molten salts. The results show that injection of steam at the high-pressure line before the steam turbine increases the cycle’s gross efficiency with respect to the reference case, estimating a reduction of carbon emissions of 6696 kg/h in the ‘fuel saving’ mode and an increase in gross power of 14.4 MW in the ‘power boosting’ mode. Hence, adapting current combined cycles for hybridization with solar power is a viable solution in the transition period towards more sustainable energy sources.