Rapid population growth and increasing energy demand in developing countries are the key drivers behind rising concerns such as energy poverty and environmental degradation. Harnessing solar energy can help the developing countries inch closer to sustainable economic growth. This paper presents the performance analysis of a solar water heating system based on an evacuated flat plate collector (EFPC). EFPCs offer higher optical performance and lower thermal losses in comparison with conventional solar collectors. In this study, a multi-parametric analysis provides the guidelines for the design and optimization of a novel low vacuum EFPC system under ambient conditions, for domestic hot water (DHW) applications. A small-scale solar thermal collector system based on a low vacuum (17.5 – 20 kPa) EFPC of a total area of 4.0 m² is designed and installed. The system is coupled with a storage tank comprising of the helical copper coil configuration inside the tank, which is used as a heat exchanger from primary loop to secondary loop. A series of real-time experiments are performed under ambient conditions from December to April. The thermal efficiency of the EFPCs reaches a maximum value of 73.2%, with the glycol-water mixture as a heat transfer fluid at an inlet temperature of 31.2 °C, when the ambient temperature is 15.3 °C, average irradiance is 679.2 Wm-2, and vacuum pressure is 20 kPa. For this duration, the exergy efficiency reaches a peak value of 16%. This EFPC system provides 100 liters of hot water at 57-69 °C per day for DHW consumption when the average ambient temperature is 24 °C. The overall results highlight the potential of EFPCs for hot water applications. Furthermore, an efficiently optimized EFPC system can also be used for space heating during the winter season.

Over the last twenty years, architects and designers have been working towards minimizing the impact that buildings have on the environment. In spite of the fact that many architects claim their buildings are environment-friendly, the claims cannot be justified unless a Life Cycle Analysis (LCA) is conducted. The two major parts of the theoretical basis of the proposed scheme are the concept of sustainability of the environment and methods of assessing the building’s environmental impacts. The objective of this report is to evaluate the possible ecological impact of an educational building through its life cycle, from extracting raw materials to the end of life. In order to accomplish the goal of the study, a single-case method of a life cycle assessment was used to determine which stage of the life cycle (manufacturing, construction, consumption, maintenance, and dismantling) made the most contribution to the overall impact. The main installation system (foundation, frame, wall, floor, roof) of a building will have an impact on the environment during its life cycle. A typical new educational building was used as a case study in Islamabad, along with an optimized LCA method based on energy consumption inventories, the material input and output, and the assessment of the environmental impact.