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Abstract: The systematic, transparent and accurate on-line energy information of the production process is quite the basis of mill energy management and conservation. An Energy Management System (EMS) was built according to the characteristics of the energy usage in a typical newsprint paper mill. The EMS first realized the process data acquisition and integration, second fulfilled the on-line energy information calculation from the integrated data. A water and steam properties query component based on IAPWS-IF97 was developed and plugged into the EMS to facilitate the energy calculation of water and steam. The practical performance in the paper mill showed that the integrated energy information of the whole mill was gained and the on-line energy supervisory was achieved. In the end a systematic, transparent and accurate energy usage profile is obtained and it would provide the valuable fundamental energy data for the further energy analysis and optimization in the EMS. [Copyright &y& Elsevier]

Abstract: Coupling exothermic with endothermic reactions is proposed as a significant improvement in reactor performance and energy integration. Furthermore, it forms an initial step for process optimization using pinch method. Through coupling of the exothermic reaction with endothermic one, oxidation with reduction, dehydrogenation with hydrogenation, hydration with dehydration, and even a series of tandem reactions, the utilization of energy and materials can be optimized. The underlying goal of this paper is to provide an extensive review through the years 1994–2011 of coupling exothermic and endothermic reactions as an important measure in process integration and intensifying. Developments in coupled reactions, classifying suitable reactors for couplings and categorizing several types of coupling exothermic and endothermic reactions are investigated in this study. Finally, various information concerning coupled reactions are presented in tables. Superiorities of novel models (coupled configurations) to the conventional configurations are clarified. Ultimately, various suggestions are proposed for further work. Results show that the short distance between heat sink and heat source can increase the efficiency of the heat transfer meanwhile incorporating two separated processes with coupled reactors can reduce the size of equipment. [Copyright &y& Elsevier]

Abstract: Apparent window size contradictions arise when optimizing simultaneously for low energy (small sizes) and visual comfort (large sizes). Diverse multi-objective optimization methods exist, but basic questions must be solved beforehand such as choosing appropriate evaluation measures. This work aims to determine the suitability of combined optimization criteria on window sizing procedures for low energy consumption with high visual comfort and performance. The paper showcases diverse measures available to valorise energy consumption and visual aspects. A series of energy and visual criteria were selected, defining acceptance thresholds for dynamic evaluations. Whole-building computer simulations were performed on a standardized office located in a temperate climate. Discrete window-to-wall ratio variations were studied to demonstrate how these criteria affect the solution space. Results were classified using a graphical optimization method, obtaining a solution space satisfying both energy and visual requirements. Most project expectations can be met within the range of sizes. However, unprotected windows barely meet acceptance criteria, needing additional control devices. Applying various related criteria with adequate values increases the diversity of acceptable solutions but too many limits it. Clear objectives and acceptance ranges have to be conceptualized in order to translate them into decisions. This becomes important when involving team design. [Copyright &y& Elsevier]

Abstract: The optimization of building cooling heating and power (BCHP) system is helpful to improve its comprehensive performance including energetic, economic and environmental aspects. However, the optimal results are closely dependent on the initial setting parameters. This paper deduces the energy consumption of BCHP system following the electrical load and presents the optimization problem of BCHP system that includes the decision variables, the objective function, the constraint conditions and the solution method. The influences of the initial parameters, which include the technical, economic and environmental parameters, the building loads and the optimization setting parameters, on the optimal decision variables and the performances of BCHP system are analyzed and compared. The contour curves of the performances of BCHP system in comparison to the conventional separation production (SP) system, and the sensitivity of the optimal decision variables to the initial parameters are obtained. [Copyright &y& Elsevier]

Abstract: The present paper reports a numerical investigation of spatial optimization of heat-exchanger by acting on its positioning in the vehicle’s cooling module. This analysis also elucidates how to act on the different parameters influencing heat-exchanger performance in order to optimize their functioning. A two-dimensional computation code permits optimizing the performance of the cooling module by positioning different heat exchangers, in both the driving and stop phases of the vehicle. The ultimate aim is to apply new control approaches to real vehicles so as to reduce pump and compressor energy consumption and thus fuel consumption. Compared to a reference “in-series” configuration of the cooling module HXs (in which the different HXs are superposed in the airflow direction), an “in-parallel” configuration (in which the different HX surfaces are in a row with respect to the air flow direction) increases the thermal power of the HXs by 4.4% and decreases the pressure losses by 0.9%. [Copyright &y& Elsevier]