###### Abstract
[3] reports the results of an experimental campaign, performed on a full-scale double-skin facade, using the in situ measurement methodology. The thermodynamic behavior of the facade is studied under real exterior climatic conditions in Romania in hot and cold seasons, and performance indicators in terms of pre-heating efficiency and dynamic insulation efficiency were determined. Three summer periods are analyzed, each corresponding to the outdoor air curtain scenario for three ventilation modes in naturally or mechanically ventilated single-story DSF buildings. Results revealed that the third ventilation scenario, which combines horizontal and vertical openings, gives the best efficiency of 71.3% in the double skin facade functioning. During the cold season, the channel facade behaved like a thermal buffer between the building and the exterior air, ensuring the requisite thermal energy for partial or integral heating of the building. case, while in the best cooling scenario it reached 88.74%, assuring a rise in the power production of 6.49%. In their article, [PERSON] et al. [6] describe a methodology for the simulation and the design of a solar tracker system, making use of the advantages that the orientation and efficiency of the PV panel offer due to the latitude and the number of hours of sunshine in the testing area. This proposed methodology was experimentally validated through the implementation of a single-axis solar tracker at a specific location (36.261\({}^{\circ}\) latitude), allowing the incorporation of a high-availability, low-precision, and low-cost tracking mechanism. Based on the results, the feasibility of this type of solar tracker for latitudes close to 36\({}^{\circ}\) was demonstrated by the lower cost of this tracking system compared to traditional commercial systems. Furthermore, this system contributed increased collection efficiency compared to a fixed device. Our results provide an excellent platform for engineering technology researchers and students to study the design theory of a sun-tracking solar system. Photovoltaic/thermal (PV/T) systems are innovative cogeneration systems that ensure the cooling of photovoltaic (PV) backsides, as well as the simultaneous production of electricity and heat. However, producing an effective means of cooling the PV back is still a challenge that affects the electrical and thermal performance of the PV/T system. In their work [7] [PERSON] et al., present a PV/T numerical model to simulate the heat flux based on the energy balance implemented in MATLAB software. The numerical model is validated through a comparison of the three-layer PV model with the NOCT model and tested under the operation conditions of a continental temperate climate. Moreover, the effect of velocity and water film thickness as important flow parameters on heat exchange and PV/T production is numerically investigated. The results revealed that the PV model strongly agrees with the NOCT variant. An efficient heat transfer was obtained while increasing the velocity and water film thickness, with optimal values of 0.035 m/s and 7 mm, respectively, at an inlet temperature of 20 \({}^{\circ}\)C. The PV/T system ensures a maximum thermal power of 1334.5 W and electrical power of 316.56 W (258.8 W for the PV). Finally, the comparison between the PV and PV/T system under real weather conditions showed the advantage of using the PV/T. One of the biggest challenges the world is facing these days is to reduce the greenhouse gases emissions in order to prevent global warming and limit its effects. Since a significant quantity of CO\({}_{2}\) emissions result from the energy production process required in industrial applications or the use of buildings, waste heat recovery is an important aspect in the fight to preserve the planet. In paper [8], an innovative waste heat recovery system, capable of recovering waste heat energy from a variety of cooling liquids used in industry or in different processes, was designed and subjected to experimental investigations.