The building sector consumes a significant portion of global energy use. In this regard, this work was undertaken to study the status of energy efficiency and conservation at a large school building in the northern part of United Arab Emirates (UAE). The annual electrical consumption at the school was analyzed and an awareness survey among the students and teachers was conducted to measure the level of awareness as well as to assess the current energy consumption practices. In order to identify energy saving opportunities, an energy audit was carried out wherein the school energy consuming systems, particularly the lighting and air-conditioning systems, were assessed. Furthermore, thermography scanning of the school building envelope was conducted to examine the building insulation and identify air leakage locations. The building electricity supply and distribution systems were assessed using power analyzer and thermography devices. The energy conservation measures identified include removing the extra lighting, installing motion sensors in classrooms and labs, as well as integrating a Networked Optimization Software with the current HVAC (heating, ventilating and air conditioning) system. The methodology consists of seven fundamental steps: (1) case study data collection (analysis of buildings and utility data); (2) survey of real operation conditions; (3) understanding of building behavior; (4) analysis of energy conservation measures; (5) estimation of energy-saving potential; (6) economic assessment; and (7) proposing Energy Conservation Measures (ECMs). In this regard, the school energy consuming systems (lighting, building envelope, and air conditioning (AC)) were examined to identify possible ways to reduce the school energy consumption. The results indicate that the cost of installing motion sensors in classrooms, and labs is approximately AED 20,000 (United Arab Emirates Dirham), which yields an annual energy saving of AED 93,691. Furthermore, with all energy saving measures, a total annual saving of AED 364,000 is anticipated, which is approximately 16% of the annual electricity bill.

This paper investigates the factors affecting the optimum insulation thickness and its pay-back period, such as heating and cooling energy requirements of building, lifetime, present worth factor, costs of insulation material and installation, costs of energy sources for heating and cooling, heating and cooling system efficiencies, and solar radiation. For this purpose, by considering two cities characterizing the hot and cold climatic conditions, the optimum insulation thickness and its pay-back period have been calculated and a detailed parametric analysis has been carried out. To achieve practical results, the ranges of the parameters considered in the study include the values typically reported in the literature. The variations in the optimum insulation thickness and the pay-back period with all parameters are presented in graphical form. Finally, order of importance and contribution ratios of the examined parameters on the optimum insulation thickness are determined with the help of Taguchi method. It is found that heating degree-days is the most efficient parameter on the optimum insulation thickness with an impact ratio of 27.33% of the total effect while the least efficient parameter is the efficiency of heating system with an impact ratio of 3.21%.

Fuel cells are energy conversion devices that directly convert chemical energy of fuels such as hydrogen to useful work with negligible environmental impact and high efficiency. This study deals with thermodynamic analysis and modeling of polymer electrolyte membrane fuel cell (PEMFC) power systems for portable applications. In this regard, a case study of powering a computer with a PEMFC is presented. Also, an inclusive evaluation of various parameters such as voltage polarization, overall system efficiency, power output, and heat generation is reported. In addition, a parametric study is conducted to study the effect of many design and operation parameters on the overall efficiency. Results show the direct influence of current density and temperature values on optimization of the design parameters in PEMFCs.