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In recent years, net zero or plus-energy buildings (PEB) have been widely analyzed and discussed for their benefits of increasing energy savings and reducing greenhouse gas emissions. A successful transition to energy-efficient buildings must, however, develop an efficient method that examines technical, economic, environmental and social criteria. In this paper, a method for design optimization based on spatial analysis combined with multi-criteria decision-making was proposed for achieving plus-energy buildings in Algeria. To apply the proposed method, a single family residential building was chosen. First, the annual energy consumption of the building at 40 locations was evaluated and the results are then interpolated for the whole country. The best energy efficiency measures and renewable energy are then chosen using the Analytic Hierarchy Process (AHP) method. Finally, energy balance and spatial analysis were carried out based on the geographical information system. The results showed the energy plus target was achieved in large parts of the country using a high-performance envelope, more efficient appliances and solar energy (solar photovoltaic and thermal). In addition, the southern provinces, mainly Adrar, Tindouf, Bechar, Ouargla, and Illizi, have identified the most suitable areas for setting up new buildings with an energy-plus target. In addition, applying the method will reduce the overall energy demand by 43 % and reduce GHG emissions in the country by around 23 % by 2030. Therefore, the method will have a significant impact on sustainability locally and worldwide. [ABSTRACT FROM AUTHOR]

Abstract Nowadays, all industry, including the agri-food sector, faces the urgent need to increase its competitiveness in order to survive in a global market. In this context, it is vital to ensure a strong, renewed and innovative industrial base throughout all stages of the value chain, capable of competing internationally and differentiating itself by the quality of its products and services. Since wealth generation cannot be dissociated from productivity, which in turn is closely related to the trinomial: processes, technologies and quality, it is concluded that the implementation of this strategy requires a commitment to the qualification of organizational management, operational management, project management and processes and productive systems themselves and associated technologies. This paper presents the characterization of the energy consumption and technologies in bakery and pastry sector, one of the most significant in the Portuguese agri-food sector. [ABSTRACT FROM AUTHOR]

Abstract Buildings are consuming a high percentage of material resources throughout the world. Green building movements have emerged at a rapid pace since the beginning of the 1990s. The green building rating system developed by the Abu Dhabi Urban Planning Council as part of the sustainable development initiative was launched in UAE in 2010 on the name of Estidama, according to which a new building can score on seven different credit categories. This paper examined the Resource Energy (RE) credit category of the Pearl Rating system on an existing typical old Emirati house and concluded that the existing residential private building stock in UAE has a high potential of becoming Estidama certified. The total points achieved were 16 out of the maximum 21 points in the RE credit category. A number of retrofit strategies were applied in the form of insulation, passive cooling integration and onsite renewable energy generation using the Autodesk Revit® 2017 with Sefaira® 2017 plugin. Future recommendations for the existing building stock are addressed. [ABSTRACT FROM AUTHOR]

Abstract Renewable energies are getting progressively widespread due to the growing worry of carbon discharges. There has been a substantial volume of advancement being made in renewable energy sources. One of the remarkable ones is wind power. The common myths of building a wind turbine in highways suburban, and coastal areas are the extent of the machine, and the turbulence may affect the performance of the turbine that ultimately may uncover a poor return on investment. In this paper, some laboratory testing was performed on a conventional turbine and a wind lens turbine to determine if there are any potential applications for the Wind lens turbines in a turbulent environment. Highways, coastal and suburban areas may prove appropriate for this kind of turbine. However, there is still additional analysis required on the effects that these turbines may have on local fauna migration patterns. It is also important to check if the noise pollution generated by the wind lens turbines are enough to cause disruption. Two different types of edges were also embraced to see whether performance in such a location relies more on blade type than the design of the turbine. From the testing in a lab-scale wind tunnel, it was found that on average the wind lens design provided a 40% increase in efficiency both in the Betz coefficient and tip speed ratio of the turbine. However, the wind lens turbine requires further assessment to determine its suitability in environments not exposed to constant wind currents such as highways. There is a possibility that the wind lens turbine can be applied in a turbulent setting with further assessment and enhancements to the manufacturing process of the turbine models. [ABSTRACT FROM AUTHOR]

Abstract Energy and water insecurities are global challenges, especially in arid and semi-arid regions. This paper proposes an optimal energy-water nexus management approach in residences using alternative energy and water resources, these alternatives are rainwater harvesting system, greywater recycling system, water storage, and gravity-fed distribution system. The Solving Constraint Integer Programming (SCIP) solver, in MATLAB's OPTI toolbox, is used to solve the multi-objective optimization problem. Simulation results show that the optimal tank sizing and system operations will minimize the capital and operational cost of the system. The solver produced a potable water savings of 20.5% and an energy savings of 62.54%. [ABSTRACT FROM AUTHOR]

Abstract The buildings around the world consume about one-third of final energy in both residential and commercial sectors. To reduce annual power consumption, however, energy saving in construction of division has a particular importance. In this paper, the effect of green roof along with rooftop photovoltaic (PV) solar panels on energy efficiency of a typical building is investigated in a comprehensive analytic approach. For this purpose, three vegetation coatings including crops, grass, and shrub as well as three commercial solar panels including CanadianSolar, Suntech, and Trina are considered and evaluated. The technical and economic analyses of this project have been simulated with DesignBuilder (DB) and PVSOL software respectively, using Net Present Value (NPV) method. According to the results, the reduction of energy consumption in presence of green roof is about 0.1%. The simulation results of PV system shows the electricity production is up to 26 MWh in a year and the return of capital will be between 6.5 to 7.5 years. In addition, the maximum reduction of carbon dioxide emissions is annually 16.31 tons which will be obtained by installing crops and Trina solar panels simultaneously. [ABSTRACT FROM AUTHOR]

Abstract Organic Rankine cycle (ORC) engines in waste-heat recovery applications experience variable heat-source conditions (i.e. temperature and mass flow-rate variations). Maximising ORC system performance while accounting for off-design operation in response to such variations is of crucial importance for the financial viability and wider adoption of this technology. In this paper, the off-design performance of an ORC engine is investigated in a heat-recovery application from a stationary internal combustion engine (ICE), employing a screw expander and two heat exchanger (HEX) architectures. Unlike previous studies where the ORC expander and HEX performance are assumed fixed during off-design operation, here we consider explicitly the time-varying characteristics of these system components. Nominal system sizing results indicate that the screw expander isentropic efficiency exceeds 80%, and that the heat transfer area requirements of plate HEXs (PHEXs) are 50% lower than those of double-pipe HEXs (DPHEX). Following nominal system design, the ORC engine operation is optimised at conditions relating to part-load (PL) operation of the ICE. Although, the heat transfer coefficients in the evaporator decrease by 30% at PL, the HEX effectiveness increases by up to 20% due to higher temperature differences between the working fluid and the heat source, and the performance of the PHEX appears less sensitive to off-design operation conditions. The optimum PL screw expander efficiency maps reveal only a minor reduction of the expander efficiency (by 2%) relative to the design conditions. Optimum off-design maps indicate that the power output of the ORC engine reduces to 72% of full-load for an ICE at 60% of full-load, and that ORC engines with PHEXs generate slightly more power for the same heat-source conditions. Overall, the tool developed predicts ORC performance over an operating envelope and allows the selection of optimal HEX and expander designs. The findings can be used by ORC plant operators to optimise the ORC engine power output given varying on-site heat-source conditions, and by ORC vendors to inform HEX and expander design decisions. [ABSTRACT FROM AUTHOR]

Abstract Advanced building structures are extremely complicated with a large number of dynamically interacting components and widely equipped with multi-zone air conditioning (ME A/C) systems. In this paper, multi-zone commercial building systems are built as second order Resistance-Capacitance (RC) models with individual zones communicating to the whole network through neighbors. The presented thermal dynamics are different from that in our previous work [8], which does not consider the wall's thermal dynamics. The second order RC models are more accurate in capturing the thermal dynamics of a building in comparison with the first order model employed in [8]. We first propose a hierarchical distributed method using ME A/C systems in commercial building for demand response. The idea of the upper layer strategy is based on the balance of building's energy demand and users' comfort level to generate reference signals. The lower layer is designed as distributed model predictive controllers (DMPC) to track the reference signals whereas energy cost and demand are reduced. Simulation results are provided to verify the effectiveness of the proposed control. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the Yangtze River Delta city group for the study, first, using data envelopment analysis estimates the energy efficiency of the city, and found that the Yangtze River Delta city group showing lower energy efficiency overall. Within the urban agglomeration 26 prefecture-level cities, Zhoushan is the only one achieving relatively effective energy efficiency. The spatial heterogeneity of energy efficiency in the urban agglomeration in the Yangtze River Delta is then measured using the Moran's I index (including local), confirming the existence of low-energy efficiency clusters centered around Hefei and clusters of high-energy agglomeration centers centered around Hangzhou. Then the spatial error model is used to test the various factors that affect the energy efficiency of the urban agglomeration in the Yangtze River Delta based on the circumvention of spatial heterogeneity. The conclusion shows that there is a positive correlation between industrial structure, investment, scale, foreign trade and energy efficiency. Government influence and system is negatively related to energy efficiency. Finally, based on the conclusion, this paper puts forward the policy suggestion of promoting the energy efficiency of the urban agglomeration in the Yangtze River Delta. [ABSTRACT FROM AUTHOR]

Abstract Buildings use significant amount of energy worldwide, with mechanical air-conditioning systems accounting for a large proportion of the total energy consumed. Utilizing natural ventilation can achieve a comfortable indoor thermal environment while reducing the use of air-conditioning and building energy consumption. However, previous studies mainly focused on either thermal comfort or energy conservation by utilizing natural ventilation. The correlation between thermal comfort and energy performance due to the effect of natural ventilation is important, but has not been studied thoroughly in literature. Moreover, natural ventilation in buildings is greatly affected by building geometry, material property, outdoor environmental condition and occupancy, which were not fully incorporated in the previous studies. This paper presents a framework based on building information modeling (BIM) to study the effect of natural ventilation on the correlation between thermal comfort and energy performance. BIM provides 3D building models with detailed geometric and material information as well as the building location and type that help determine the outdoor environmental condition and occupancy, thereby improving the accuracy of natural ventilation simulation. A case study was conducted using the proposed framework, aimed at investigating the natural ventilation in a residential flat in Hong Kong at different seasons. The results show that utilizing natural ventilation cannot always achieve thermal comfort. Natural ventilation brings cool air in late spring (April) during which the indoor temperature can be controlled at a comfortable level and the energy use for mechanical ventilation can be saved. The proposed framework helps evaluate the natural ventilation in buildings for maintaining indoor thermal comfort at minimal energy use, thereby creating a more sustainable built environment. [ABSTRACT FROM AUTHOR]

Abstract Residential sector has been recognised as a critical sector for energy conservation in Singapore. Research gap exists to understand the relationship of personality traits, demographics and energy behaviour of the residents. Through detailed questionnaires, demographics, energy conservation behaviour and Big Five personality traits were collected from the households in both public and private housing. The sample size of this study consists of 394 households. The results show that agreeableness, openness and conscientiousness have significant positive correlations with different aspects of energy conservation behaviour. In addition, the results illustrate that household income level and highest education level had statistical correlations whereas age and gender have no statistically significant correlation with energy conservation behaviour. Detailed discussion has been provided in this paper. Lessons from the study can help to refine current energy-saving campaigns in Singapore. [ABSTRACT FROM AUTHOR]

Abstract It has been a hot issue to investigate the cement production associated with potential effects of its environmental emissions from the perspective of conversion efficiency. This paper aims to analyzethe thermal process containing the energy and resource accounting and conversion process with exergy metrics. The resource exergy conversion efficiency, exergy loss rate, and recycling rate are calculated and compared considering each section of the cement production chain. The results show that the milling stage has the highest conversion efficiency, followed by the clinker calcinations, while those of raw material preparation and pulverized coal preparation are much lower. Due to the temperature differences, the clinker calcination section has the highest exergy loss rate, followed by the waste gas treatment section. The raw material preparation section has a low exergy loss without high temperature stages. The pulverized coal preparation and cement milling sections have the lowest exergy loss. Also, coal power preparation section has the highest recycling ratio, followed by raw material preparation with large amount of sensible heat exergy, while the clinker calcination section has a lower ratio due to coal combustion. [ABSTRACT FROM AUTHOR]

Abstract Most of the production facilities in Europe make use of compressed air to drive equipment for manufacturing and Compressed Air Systems (CAS) account for about 10% of the total electrical energy consumption of European industries. Therefore, reducing CAS energy consumption is a crucial task to meet the European goals of improving energy efficiency and reducing environmental impact of the industrial sector. This work is part of a wider research activity aimed at developing a strategy to optimize the energy use in CAS. In particular, this paper shows the importance of monitoring energy consumption and control energy use in compressed air generation, to enable energy saving practices, enhance the outcomes of energy management projects, and to guide industries in energy management. We propose a novel procedure in which measured data are compared to a baseline obtained through mathematical modelling (i.e. regression functions) to enable faults detection and energy accounting, through the use of control charts (i.e. variations' control and the Cumulative Sums). The effectiveness of the proposed methodology is demonstrated in a case study, namely the compressed air system of a pharmaceutical manufacturing plant. [ABSTRACT FROM AUTHOR]

Abstract Cities account for over 75% of all primary energy usage in the world with buildings making up the bulk of this usage. It is well acknowledged that the building energy usage is greatly impacted by urban context and thus understanding the relationships between building energy use and surrounding urban systems is critical for more energy efficient and holistic planning. This paper proposes a Data-driven Urban Energy Analytics (DUE-A) workflow to investigate and quantify the relationships between building energy usage and the spatial proximity of other urban systems. A case study of 530 buildings in a mid-size city in the Unites States is conducted to validate the performance of the workflow and demonstrate the statistical significance of relationships between building energy use and spatial proximity of other systems. Results show that spatial proximity of other buildings, roads and trees can have both positive and negative impacts on the mean, variability and distribution of building energy usage, and indicate that more holistic planning and design of cities could unlock urban energy efficiency and low-carbon municipal pathways. [ABSTRACT FROM AUTHOR]

Abstract Passively designed buildings are the tradition of historic areas of metropolitan Cairo. According to UNESCO, Cairo was inscribed on the World Heritage in 1979 under the title of "Islamic Cairo", recognizing its unquestionable historical, archaeological and urbanistic importance. Among Islamic Cairo Heritage buildings, Wekalet El-Ghouri is located in Al-Azhar area, was built in 1504 by the Memluk Sultan Qunsuwah El Ghouri. This research paper aims to investigate such historical passive design of Wekalet El-Ghouri in terms of energy efficiency simulations using eQuest, whereas sustainability assessment used a developed generic rating criterion for existing buildings. The 40 cm brick walls Wekala building was examined in comparison to its images; 12 cm, and 25 cm envelopes and simulated to compare its green rating calculated by the generic optimized rating criterion. The original passive case of the building showed the highest earned credit points by the generic criterion. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes novel decentralized control design methods for occupant comfort and energy saving in smart multi-zone buildings. First, the graph-based modeling technique for buildings is utilized to obtain a simplified lumped model for thermal dynamics of zones. Second, the graph theory is employed to derive features of the model useful for the control design. Next, two methods are proposed based on the pole placement in linear matrix inequality (LMI) region technique and the Lyapunov inequality to synthesize decentralized controllers to track the reference temperatures set by users for their thermal comfort and to save energy. The effectiveness of the proposed designs are then illustrated in a numerical example. [ABSTRACT FROM AUTHOR]

Abstract The impact of existing buildings on the environment is on the rise; thus to achieve environmental sustainability requires sustainable upgrade (SU) of existing built facilities. Over the years, SU has focused on technologies with little attention given to the nature and conditions of existing buildings. The purpose of this paper is to identify existing building characteristics that impact SU. A detailed literature review on the nature and characteristics of existing buildings, as well as energy and environmental performance was undertaken. A survey questionnaire with all the determinants of existing buildings was administered to sustainability and construction professionals in Australia. The results show that size of building, age of building, U-value of wall, U-value of ceiling, area of external wall, thickness of insulation materials, occupancy, size of window opening, life span of sustainable technologies, and the type of building impact sustainable upgrade of existing buildings for energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract The impact of existing buildings on the environment is on the rise; thus to achieve environmental sustainability requires sustainable upgrade (SU) of existing built facilities. Over the years, SU has focused on technologies with little attention given to the nature and conditions of existing buildings. The purpose of this paper is to identify existing building characteristics that impact SU. A detailed literature review on the nature and characteristics of existing buildings, as well as energy and environmental performance was undertaken. A survey questionnaire with all the determinants of existing buildings was administered to sustainability and construction professionals in Australia. The results show that size of building, age of building, U-value of wall, U-value of ceiling, area of external wall, thickness of insulation materials, occupancy, size of window opening, life span of sustainable technologies, and the type of building impact sustainable upgrade of existing buildings for energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract Wastewater treatment plants (WWTPs) are considered as energy-intensive facilities. Against the background of stricter policy requirements and discharge standard, thousands of municipal WWTPs are experiencing upgrading and reconstruction in China. However, the accompanying energy consumption cannot be ignored. Based on the statistical analysis of energy consumption and relevant factors from data of more than six thousand WWTPs over China, in this paper we analyzed the most influential factors related to energy consumption, which include treatment technology, wastewater amount, removed pollutants, social and economic characteristics, etc. Furthermore, we set up systematic method of energy performance assessment for WWTPs and explored the potential of energy saving in WWTPs. Results showed that processing capacity, organic pollutant concentration, discharge standard and economic factors have major effects on energy efficiency. Although sludge treatment and disposal normally consume intensive energy, it is possible to recover energy from biomass in the sludge. The results indicate that there is huge potential for energy saving and recovery in WWTPs, and we propose a conceptual roadmap for energy efficiency improving in WWTPs in China. [ABSTRACT FROM AUTHOR]

Abstract Shipping is a major contributor to the global CO 2 emissions. It is important to improve the ship energy efficiency and reduce the ship emissions. Various emission reduction measures have been proposed to reduce the ship emissions. In order to evaluate the efficiency of these emission reduction measures, it is necessary to evaluate the reduction of fuel consumption for these measures. However, due to the complex of ship energy system, it is difficult to assess the ship fuel consumption under different scenarios considering both operational and weather conditions through physical systems or simulation models. In this paper, a Gaussian process metamodel is developed to predict the ship fuel consumption for different scenarios. This model not only considers the effects of operational conditions such as speed and trim, but also takes into account the impacts of weather conditions such as wind and wave effects. The effects of these factors on ship fuel consumption are further evaluated. The case study indicates the accuracy and efficiency of using Gaussian process metamodel for ship energy consumption prediction. [ABSTRACT FROM AUTHOR]

Abstract For the last decades energy efficiency initiatives have avoided enormous amounts of energy consumption, to the favor of the environment and consumer expenditures. Although there is still a big potential for further energy efficiency improvements it is time to move further and start preparing the whole energy system for the challenge of oversupply from intermittent renewable energy sources, particularly in the power sector. In 2015 the maximum one-hour power oversupply from wind turbines alone in Denmark happened the 26th of June, peaking at around 900 MW and the oversupply over a 15-hour period was 10 GWh. Known solutions to make use of oversupply in the power sector are power export, energy storage and halting the power generation. The power export needs to rely on sufficient capacity at local interconnectors, power demand in the importing country and there is an economic gain in the export. Energy storages can range from storing of power in batteries, pumped hydro, synthetic fuels to fuel displacing at other energy sectors. The last option is stopping the turbines, which should be avoided. The optimum energy storage would have large capacity, fast charging, high recovery efficiency and low cost. Scoring high on all criteria’s can be difficult when focusing on a single energy sector. By widening the perspective and start taking advantages of synergies between the energy sectors there is a possibility to score high on all three criteria’s. In this paper the potential of utilizing synergies between the power and heat sectors will be explored by considering the projections for the Danish energy system in 2025. The result of the analysis shows the optimum energy storage of renewable power is achieved through fuel displacement in the heating sector in combination with utility sized heat pumps, electric boilers and large thermal storages. [ABSTRACT FROM AUTHOR]

Abstract Durability is an important aspect that has not to be neglected in ZEB design. The requirements for buildings energy needs reduction and increase of renewable energy sources stimulated designers to integrate technologies in an efficient way. This ambitious goal must meet the capacity of the technical solutions to guarantee their performances over the years. The durability of materials and technologies is a topic that warrants further analyses in order to assess the proper efficiencies and the expected lifetime of a ZEB. Typically the energy balance of a ZEB is calculated by considering the annual energy flows or rarely the whole life cycle. The most used approaches consider constant performance of materials and technical elements over the lifespan. However, the performance loss of a single element can cause an imbalance in the behavior of a ZEB, for which persists a thin balance between inlet and outlet flows. The paper provides a critical point of view on this issue paying attention on the following technical solutions implemented in a case study for which the current scientific literature provides analysis on the degradation during their lifetime: glazing systems, VIPs, PV panels and GSHPs. [ABSTRACT FROM AUTHOR]

Abstract A module of ceramic tile with integrated a silicon amorphous thin film solar cell was tested in working conditions. The ceramic modules were installed on a ventilated façade in a 3 stories laboratory building completely equipped with sensors to detect the thermal and energetic behavior of the prototype. The experimental campaign aimed at monitoring the energy and thermal performances of the ventilated BIPV façade in the current configuration. The paper describes the output of the experimentation. Specifically, the operative temperature, the global efficiency and the electric production of the system have been evaluated in real working condition. [ABSTRACT FROM AUTHOR]

Abstract Lighting systems have a fundamental role for the overall buildings energy consumption. Therefore, remarkable efforts are required for optimizing the lighting systems energy use and for finding new daylight harvesting solutions. In this paper, the impacts on daylight harvesting provided by different room and window geometries and their effects on energy savings are presented. An academic classroom with only one window is chosen as case study and it is supposed that the window orientation is modified according to the four cardinal points. A climate-based approach was chosen for the multiple simulations, carried out via DIVA software, by assuming: square and rectangular classroom geometries with the same total area; square and rectangular window shapes having Window to Floor Ratios (WFRs) equal to 8% and 12%; two different dimmable lighting systems, in order to quantify the energy savings, by considering fluorescent and LED dimmable lamps. The daylight analysis, performed by evaluating both the Daylight Factor (DF) and the Daylight Autonomy (DA), showed that room and window geometries have high influence on daylight harvesting maximization, allowing remarkable energy savings (up to 48.5%) with respect to non-dimmable lighting system. In particular, the best energy result, equal to 467.5 kWh/yr, was obtained with rectangular room and window geometries coupled with LED lamps and WFR equal to 12%. [ABSTRACT FROM AUTHOR]

Abstract The paper presents the operation mode of a ventilation chimney placed in a historical building through the use of Design Builder, a modeling and dynamical simulation software. The aim is to verify the improvement of the comfort level and energy efficiency of the simulated environments through the usage of the duct as a passive ventilation system. The method adopted to intervene in a complex system, such as that represented by historic buildings, is to enhance the preexisting architectural values through their conversion into devices able to improve the performance of the building in terms of CO 2 and energy consumption reduction. The case study is Palazzo Bruni-Riga, a valuable building located in the historic center of L’Aquila. The building has a double ventilation duct, probably also used as a light-pipe, in correspondence of two windowless rooms of similar dimensions. The dynamical simulations presented concern the analysis of the passive ventilation duct and its effects on the thermo-hygrometric well-being of the modeled rooms. The goal of this paper and this research in general, is that the wise use of such devices installed in times when there were no air conditioning systems, allows you to better use the ventilation chimneys, and have the maximum thermal indoor comfort, with the minimum effort and use of mechanical systems. Through the simulations it was possible to verify that through the use of the ventilation chimney, it is possible to have the indoor comfort conditions, by checking the Fanger indices for the data obtained from the simulations carried out. [ABSTRACT FROM AUTHOR]

Abstract Building envelopes under various climates behave differently, in this paper the actual thermal transmittance or U-value of five different wall assemblies are evaluated and compared with values, calculated using standard EN ISO 6946. The experiment is carried out in five test buildings with equal spatial orientation, the same ceiling and floor assemblies as well as the same windows and doors mounted in each building. The thermal transmittances for these partitions are assumed to be well known and therefore, by knowing temperature difference and heat sources inside the building, the thermal transmittance of wall assembly can be calculated. It is shown that for small buildings the corner effects are of great importance and therefore a more precise calculation of them are done. [ABSTRACT FROM AUTHOR]

Abstract In this paper is the first attempt to structure energy management in buildings retrofitted by Energy Service Company to maintain designed energy performance level. The energy performance of multifamily buildings is investigated. More specifically, ex-post energy data of the buildings are analysed to see the dynamics of the energy performance. The analysis is based on a unique dataset that combines data from energy meters and energy monitoring system. The results indicate that multifamily buildings with proper energy management keep designed energy efficiency level meanwhile providing in the energy performance contract guaranteed indoor temperature in space heating season. [ABSTRACT FROM AUTHOR]

Abstract The non-energy-intensive nature of the food processing industry has led to a common trend where management energy has only secondary role to other productions costs, resulting in minimal oversight from management and short-term solution. Within cold storage facilities, 60–70 % of the electrical energy used is for refrigeration. For fish processing companies, one of the main energy users are the refrigeration units. The aim of the current paper is to make an algorithm based on case study in order to evaluate fish refrigeration electricity consumption and compare results with similar studies. Energy consumption for processing fish depends on installation, equipment and process. Process of cooling and refrigeration builds up about 16 % of the total energy in canning sector. This study has shown that refrigeration builds up about 24 % in average. From calculations, it can be concluded that average electricity consumption for fish refrigeration at the factory is 380 kWh per ton of product. In literature, sources it can be found that electricity consumption for industrial freezers are 70–130 kWh per ton of product. [ABSTRACT FROM AUTHOR]

In recent years, demand-based control in HVAC systems have achieved a great amount energy saving by providing precise services in according to actual demand. As the premise of determining actual demand, occupancy information has a significant impact on building heating, cooling and ventilation in building control and energy auditing. In this paper, a Wi-Fi probe based occupancy detection method is applied to detect the occupancy in typical office buildings. Given the Wi-Fi coverage and smart devices are widely used in modern buildings, Wi-Fi probe requires no initial investment and could scan the Internet connection request and response of occupants. Previous studies suggest time-series and stochastic characteristics of occupancy information, this research proposed a Time-Window based Markov Chain (TWMC) model to detect occupancy. An on-site experiment was conducted in this study to validate the proposed method. The results report an accuracy of over 80% (x-accuracy when x equals 4). Compared to actual occupancy profile, the proposed model shows over 88% of supply air amount reduction in energy simulation with an absolute deviation less than 20%. By integrating the proposed TWMC model based on Wi-Fi probe and demand-based control system, the energy consumption of HVAC system could be significantly reduced. [ABSTRACT FROM AUTHOR]

The indoor temperature in traditional Variable Air Volume (VAV) systems is controlled synchronously by increasing or decreasing the damper of the valve based on the return air temperature. However, the thermal comfort cannot be guaranteed since the load inside may not be evenly distributed, energy is wasted due to continuing cool down space even though no occupants inside. Thus, this paper introduced a coordinated control strategy aiming to improve energy efficiency and thermal comfort of large-scale rooms. A case study was presented on a summer day to show the benefits of the proposed method. The selected chamber is divided into two subzones with each controlled by a separated VAV box. Typically, each zone can be controlled independently by regulating its corresponding VAV box to track the temperature set point. Since occupants may move randomly, the worst scenario is that one subzone was fully packed. In this case, the corresponding representative temperature cannot be cooled down to its set point, and an extra airflow rate may be needed using its neighbor VAV box to cool down the air inside. To achieve this function, the thermal coupling effect between zones is considered with the Heat Transfer Coefficient (HTC) integrated into the control platform established in TRNSYS. The simulation results show the proposed control can deal with the dynamic variation of load distributions inside. The introduction of heat exchange between adjacent zones can improve the accuracy of the temperature controls. The energy consumption of the variable speed supply fans was compared with conventional control, approximately 10% of energy saving was achieved. [ABSTRACT FROM AUTHOR]

In the 21st conference of the parties (COP21) of United Nations, both renewable energy and energy efficiency were recognized as essential means for low-carbon future. It is estimated that around 20-50 % of energy input to industries is lost as waste heat. Low-grade heat is abundantly available from renewable sources like solar, biomass and geothermal. There is a need to develop technologies which can utilize very low-grade heat (<100 °C). This paper reports the design and optimization of heat driven systems for utilizing very low-grade waste heat in tropical conditions. The Ejector Refrigeration System (ERS) has been selected, designed and simulated to producing cooling from low-grade heat. Organic Rankine Cycle (ORC) has been designed and simulated for producing power and a novel hybrid configuration is proposed to produce power and cooling simultaneously. The ERS and ORC optimization involves the selection of most suitable working fluids, working conditions, sizing of components, and optimizing configurations. For system level modeling with real properties of working fluids, EES (engineering equation solver) and EBSILON (a commercial thermal system design tool) are being used in this work. For design optimization of ejector, EES and ANSYS-FLUENT (a commercial CFD solver) are being used. With EES model, the ORC system has been found to operate at 5.2 % overall efficiency. The results from EES model have been verified by the EBSILON model. The EES model for ERS gives the COP of 0.48. The EES model developed for ejector nozzles can be used to design any supersonic nozzle for the desired inlet and outlet pressers and exit velocity. A novel hybrid cycle configuration has been proposed. This novel configuration uses ejector simultaneously for two purposes; to reduce the work-producing-expander outlet pressure and to compress vapor for cooling cycle. The preliminary modeling results show that the output of this configuration is 27 % higher than simple ORC. [ABSTRACT FROM AUTHOR]

Air conditioning and cooling systems account for about 40 % of total electricity usage in data centers. Free cooling is a novel and promising technology that can decrease the load ratio of electrical chiller and save cooling energy consumption accordingly, through making full use of natural free cooling source. In this paper, four typical free cooling systems are analyzed and compared, to show their mechanisms, main features, energy saving effects and applicable situations respectively. (1) Direct fresh air cooling is of the highest free cooling potential. However, it is hard to meet indoor air quality demand due to the indoor-outdoor air mixing. (2) Rotating wheel heat exchanger can be used for indirect free cooling, since indoor and outdoor air flow in different paths for heat exchange. While its power usage effectiveness (PUE) increases inevitably under the same climatic conditions. (3) Heat pipe can be integrated with rack back plate to enhance heat transfer with free cooling sources. Its cooling efficiency can increase by 3-5 times compared to traditional heat exchangers. (4) In water-based free cooling system, a heat exchanger is installed in parallel with electrical chiller and the system can work under three modes according to different outdoor temperature. Increasing the load ratio of free cooling can decrease PUE and save electricity usage. In practical applications, the cooling system design for data centers depends on various factors, such as indoor air quality requirement, local climatic conditions, energy saving demands, room space, capital investment and operation costs. [ABSTRACT FROM AUTHOR]

Ventilation is one of the most energy demanding parts of deep underground mining operations due to the extensive amounts of energy needed to cool (or heat) the substantial amount of air flow in underground workings. This considerable amount of energy demand can be partially satisfied by extracting renewable energies or using alternative energy solutions available at mine sites. In Canada, some mining operations have the opportunity to create a Seasonal Thermal Energy Storage (STES) unit by blowing mine intake air through large volumes of rock mass dumped in a decommissioned pit. This technique allows for creation of the so-called “Natural Heat Exchanger (NHE)” which moderates seasonal air temperature oscillations. This paper signifies a novel heat transfer model for performance assessment of a NHE system. It investigates the potential for energy savings by implementation of variable number and position of ventilation trenches in underground mines. In this regard, a 3-D heat transfer model is developed to evaluate the thermal storage and the heat transfer between broken rock mass and ventilated air flow and also to specify how design parameters such as position and number of ventilation trenches will affect the heat transfer performance as well as the total energy savings. The results of this study show that NHE can be applied in thermal management of underground mines with the aim of decreasing energy consumption for heating, cooling and ventilation purposes. [ABSTRACT FROM AUTHOR]

This paper proposes a real-time certification system using Internet of Things (IoT) technologies to apply near-realtime data for measuring indoor comfort. We make use of the parameters of Leadership in Energy and Environmental Design (LEED), which is a building standard and certification system used across the world. These certifications basically use static values, for example, energy efficiency of electricity, water, and gas usage, while IoT technologies are provided with near-real-time values. The proposed certification system has the potential to provide information on a home's current status, for instance, age deterioration. This paper describes means of collecting real-time data using IoT technologies and provides results regarding how the system provides useful information to residents for maintaining indoor comfort. To test the system's applicability, we utilized data collected by two household types for one month. The results indicate the difference between static and dynamic data using the certification system. [ABSTRACT FROM AUTHOR]

Urban building energy models are emerging tools meant to analyze and understand the energy performance of multiple buildings within a dense urban area. However, accurate performance prediction of these models remains a challenge because of their inability to account for the inter-building energy dynamics and interdependencies in an urban area. This paper analyzes the literature to highlight the limitations of current urban scale energy simulation models and proposes a new Data-driven Urban Energy Simulation (DUE-S) workflow capable of capturing inter-building effects on a building’s energy usage. Specifically, DUE-S combines a data-driven machine learning model with a traditional physics-based energy simulation to enable more accurate simulation results on multiple scales (single building, community, urban). More accurate and robust energy performance characterization and simulations of urban buildings could provide valuable insight on early-stage building design, building conservation and portfolio management, and urban energy efficiency policy-making crucial to helping our cities transition to a more sustainable energy future. [ABSTRACT FROM AUTHOR]

In this paper we test the hypothesis of convergence in China’s regional energy efficiency in agriculture over a time period that ranges from 1995 to 2014. The potential convergence is analysed by two different methodologies in this paper. Firstly, the output value of the agriculture energy consumption per unit is tested and the sigma-convergence is presented by means of standard deviation (SD). Secondly, the widely-used Barro-type regressions indicate that the unconditional beta-convergence exists during the entire period. [ABSTRACT FROM AUTHOR]

While technology advancements are increasingly improving the energy efficiency of buildings, occupant behavior remains a critical factor in ensuring the effectiveness of such enhancements. To this end, numerous eco-feedback systems have been developed to reduce building energy use through adjusting occupants’ behaviors. The information represented in an eco-feedback system affects the users’ engagement, motivation, and interpretation. In this paper, we introduce a new information representation method in which a building information model (BIM) is integrated with energy use information to enhance visual representation of energy use. The BIM-integrated energy visualization approach developed in this paper allows users to visualize energy consumption values of each building room through a color-coding scheme in an as-built BIM. Colors correspond to the levels of energy consumption in individual rooms compared to other rooms in a building, which enables a visually intuitive normative comparison for building eco-feedback systems. This representation may lead to increased user engagement in and improved interpretation of eco-feedback systems. [ABSTRACT FROM AUTHOR]

Even if numerous studies were published over the last decades about the CO 2 capture process by aqueous amine solutions, only one paper was found so far in the literature concerning the use of microwave (MW) to regenerate the spent solutions. The present work was then performed to investigate the regeneration efficiency of MEA aqueous solutions by MW while testing various amine concentrations including the well-known 30 wt%. Stripped CO 2 quantities were compared to the MW energy absorbed by the solution to find the optimal regeneration conditions. The heating rate of solutions by MW was found to be influenced by their heat capacity and viscosity, two parameters with opposing effects giving rise to a maximal heating rate for concentrations of 50-60 wt% MEA. By performing absorption and regeneration cycles, the cyclic CO 2 capacity of each solution was found and compared to the amount of MW energy absorbed by the solution during the stripping step. The lowest energy per mole of stripped CO 2 ratio was found for the 50 wt% MEA solution which ratio is 33 % lower than the value found for the benchmark 30 wt% MEA. [ABSTRACT FROM AUTHOR]

Daylightophil concept towards architectural design plays a crucial role in building thermal comfort, as a way to highperformance architecture in which multi-objective optimization technics adopted to enhance interaction of building envelope and level of energy efficiency. Performance-based design is to control heat transfer from inside to outside, solar heat load from outside to inside, better efficiently in solar energy, maximum usage of sunlight, innovative building envelope for green biotecture, support inside of the building from glare etc. This paper presents a comprehensive review of Innovative Building Envelope Technologies, which interact with solar energy. Different types of such building envelope technologies, which are explored, are: building window shading, energy frame, vertical garden, solar façade (BIPV, BIPV/T, BIST), adaptive solar façade, building integrated intelligent materials, double skin façade, climate adaptive building shell, micro-algae façade system. Then the mentioned technologies are evaluated according to solar energy gain efficiency and architectural adaptability factors by a group of experts. The results of the research show that in terms of architectural adaptability vertical gardens along with algae bioreactor façade systems and in terms of energy efficiency, algae bioreactor façade, solar facades (BIPV/T) and Climate adaptive building shells (CABS) acquire the highest score. The overall evaluation results demonstrate that CABS as well as vertical garden, solar façade (BIPV/T type), Adaptive solar Envelope (ASE) group stand at the second and the third levels, respectively and algae bioreactor façade devotes the highest average score to itself. The results emphasized on the role emerging technologies such as algae bioreactors and other green developments on future building envelopes. [ABSTRACT FROM AUTHOR]

Energy Performance Certificates (EPCs) are expected to be a useful instrument for stakeholders (including final users), enabling to compare building energy performances within a purchasing/renting decision process. Thereby, EPCs should have a direct impact on the value of the properties, affecting the market attractiveness, as well as driving the investors in the energy renovations process. Nevertheless, a survey to real estate agents reveals a perceived low reliability of EPCs, representing one of the main barriers in their full implementation. The paper presents the EPCs impact in the building market and an analysis on energy efficient buildings in eight European countries. [ABSTRACT FROM AUTHOR]

ABRACADABRA is an European Project funded by the Horizon 2020 Program, based on the assumption that substantial increase in the real estate value of the existing buildings can play a key role in the deep renovation. The project aims at demonstrating to the key stakeholders and financial investors the attractiveness of a new renovation strategy based on volumetric Add-ons and Renewable energy sources (AdoRES) intended as one (or a set of) Assistant Building unit(s) - like aside or façade additions, rooftop extensions or even an entire new building construction - that "adopt" the existing buildings (the Assisted Buildings) to achieve nearly zero energy. The creation of these AdoRES aims at reducing the initial investment allocated for the deep renovation of the existing building creating an up-grading synergy between old and new. The ABRA strategy can thus result in the implementation of a punctual densification policy that aims at fostering the investments in deep renovation of the existing built environment, driving process innovation in the construction and the real estate sector. The paper, after outlining the main aspect of the project, focuses on a case study in Italian context, where different technological solutions and related economic impact are analysed: from a deep renovation to AdoRES strategies and different scenarios of renovation. The preliminary feasibility study and cost assessment, show the benefit given by the presented strategy in overcoming actual financial e tecnical barriers. [ABSTRACT FROM AUTHOR]

Since climate changes are now evident, it is not only important to achieve high level of energy efficiency, but also to think about retrofit actions in order to mitigate the natural hazard impacts and to make buildings resilient. The paper focuses on climate change effects in summer and investigates how it is possible to reduce them through façade retrofitting solutions (external insulation, PCM, green wall, cool materials) in Mediterranean climate. The goal is to develop a set of climatic resilience indicators for opaque envelopes in order to consider resilience ability against climate change, both inside and outside of buildings. [ABSTRACT FROM AUTHOR]

Data centers are facilities hosting a large number of servers dedicated to data storage and management. In recent years, their power consumption has increased significantly due to the power density of the IT equipment. In particular, cooling represents approximately one third of the total electricity consumption, therefore efficiently cooling data centers has become a challenging problem and it represents an opportunity to reduce both IT energy costs and emissions environmental impact. The efficiency of computers room air conditioning (CRAC) systems can be increased using both advanced control techniques and new free cooling technologies, such as the indirect adiabatic cooling (IAC), that is the humidification of air under adiabatic conditions. Water sprinkled by spray nozzles humidifies and cools down the air taken from the outside, which then cools down the computers room air by means of a crossflow heat exchanger. In this way, the process air temperature is economically reduced and the cooling process is effective even when the outside temperature is warmer than that desired in the computers room. Beside the traditional approach, that improves energy efficiency of CRAC systems through advanced hardware design, nowadays advanced control systems offer the opportunity to improve both efficiency and performance by mostly acting on software components. In particular, a model-based paradigm can result very useful in the design of the controller. This approach involves three main steps: plant modelling, controller design, and simulations. In this paper, First-Principle Data-Driven (FPDD) techniques have been considered in the modelling phase, in order to obtain a model as simple as possible but accurate enough. All the main components of the plant, such as fans, spray nozzles, heat exchanger, and the computers room have been taken into account and they have been calibrated exploiting real data. The dynamics of the computers room variables (e.g. temperature) are slower than those of the components of the cooling system, due to higher thermal inertias of the computers room. Therefore, fans, heat exchanger, and spray nozzles are described by static models, whereas the computers room is described by a LTI dynamic model. Once obtained a model of the plant, a simulation environment based on Matlab/Simulink is designed accordingly. The developed control system is hierarchical: a supervisor determines the best combination of CRAC water and process air flows which minimizes the total power consumption, while satisfying the cooling demand. This system energy management problem is formulated as a non-linear optimization problem, subject to internal air condition requirements and system operating constraints. The optimization problem is repeatedly solved at each supervision period by using a population based stochastic optimization technique (Particle Swarm Optimization). Results of simulations show that the proposed control system is effective and minimizes the input electric power while satisfying both the data center thermal load and system operating constraints. [ABSTRACT FROM AUTHOR]

Energy Performance Certificates (EPCs) are expected to be a useful instrument for stakeholders (including final users), enabling to compare building energy performances within a purchasing/renting decision process. Thereby, EPCs should have a direct impact on the value of the properties, affecting the market attractiveness, as well as driving the investors in the energy renovations process. Nevertheless, a survey to real estate agents reveals a perceived low reliability of EPCs, representing one of the main barriers in their full implementation. The paper presents the EPCs impact in the building market and an analysis on energy efficient buildings in eight European countries. [ABSTRACT FROM AUTHOR]

ABRACADABRA is an European Project funded by the Horizon 2020 Program, based on the assumption that substantial increase in the real estate value of the existing buildings can play a key role in the deep renovation. The project aims at demonstrating to the key stakeholders and financial investors the attractiveness of a new renovation strategy based on volumetric Add-ons and Renewable energy sources (AdoRES) intended as one (or a set of) Assistant Building unit(s) – like aside or façade additions, rooftop extensions or even an entire new building construction – that “adopt” the existing buildings (the Assisted Buildings) to achieve nearly zero energy. The creation of these AdoRES aims at reducing the initial investment allocated for the deep renovation of the existing building creating an up-grading synergy between old and new. The ABRA strategy can thus result in the implementation of a punctual densification policy that aims at fostering the investments in deep renovation of the existing built environment, driving process innovation in the construction and the real estate sector. The paper, after outlining the main aspect of the project, focuses on a case study in Italian context, where different technological solutions and related economic impact are analysed: from a deep renovation to AdoRES strategies and different scenarios of renovation. The preliminary feasibility study and cost assessment, show the benefit given by the presented strategy in overcoming actual financial e tecnical barriers. [ABSTRACT FROM AUTHOR]

Since climate changes are now evident, it is not only important to achieve high level of energy efficiency, but also to think about retrofit actions in order to mitigate the natural hazard impacts and to make buildings resilient. The paper focuses on climate change effects in summer and investigates how it is possible to reduce them through façade retrofitting solutions (external insulation, PCM, green wall, cool materials) in Mediterranean climate. The goal is to develop a set of climatic resilience indicators for opaque envelopes in order to consider resilience ability against climate change, both inside and outside of buildings. [ABSTRACT FROM AUTHOR]

Data centers are facilities hosting a large number of servers dedicated to data storage and management. In recent years, their power consumption has increased significantly due to the power density of the IT equipment. In particular, cooling represents approximately one third of the total electricity consumption, therefore efficiently cooling data centers has become a challenging problem and it represents an opportunity to reduce both IT energy costs and emissions environmental impact. The efficiency of computers room air conditioning (CRAC) systems can be increased using both advanced control techniques and new free cooling technologies, such as the indirect adiabatic cooling (IAC), that is the humidification of air under adiabatic conditions. Water sprinkled by spray nozzles humidifies and cools down the air taken from the outside, which then cools down the computers room air by means of a crossflow heat exchanger. In this way, the process air temperature is economically reduced and the cooling process is effective even when the outside temperature is warmer than that desired in the computers room. Beside the traditional approach, that improves energy efficiency of CRAC systems through advanced hardware design, nowadays advanced control systems offer the opportunity to improve both efficiency and performance by mostly acting on software components. In particular, a model-based paradigm can result very useful in the design of the controller. This approach involves three main steps: plant modelling, controller design, and simulations. In this paper, First-Principle Data-Driven (FPDD) techniques have been considered in the modelling phase, in order to obtain a model as simple as possible but accurate enough. All the main components of the plant, such as fans, spray nozzles, heat exchanger, and the computers room have been taken into account and they have been calibrated exploiting real data. The dynamics of the computers room variables (e.g. temperature) are slower than those of the components of the cooling system, due to higher thermal inertias of the computers room. Therefore, fans, heat exchanger, and spray nozzles are described by static models, whereas the computers room is described by a LTI dynamic model. Once obtained a model of the plant, a simulation environment based on Matlab/Simulink is designed accordingly. The developed control system is hierarchical: a supervisor determines the best combination of CRAC water and process air flows which minimizes the total power consumption, while satisfying the cooling demand. This system energy management problem is formulated as a non-linear optimization problem, subject to internal air condition requirements and system operating constraints. The optimization problem is repeatedly solved at each supervision period by using a population based stochastic optimization technique (Particle Swarm Optimization). Results of simulations show that the proposed control system is effective and minimizes the input electric power while satisfying both the data center thermal load and system operating constraints. [ABSTRACT FROM AUTHOR]

Although the Moroccan climate is generally mild and temperate, both heating in winter and cooling in summer are required to reach comfort levels in different regions. The building energy consumption related to the heating and cooling can be reduced by several solutions like the use of suitable shading. This paper presents a study of the effect of overhangs and fins on the heating and cooling energy demand in the city of Marrakech. A simulation study has been performed by using the TRNSYS Simulation Program to determine therequired energy for heating and cooling depending on orientation of the window and the overhangs and fins dimensions. Furthermore, practical tables, to determine rates of cooling energy reduction by using overhangs, were established. [ABSTRACT FROM AUTHOR]

Gas-phase polymerization is a method that is widely used in the polymer production process. The heterogeneous reaction between monomer gas and solid catalyst takes place in the fluidized bed reactor to produce the polymer product. The design and production planning of this process is a difficult task due to the complicated fluid behavior and polymerization reaction inside the fluidized bed reactor. In this paper, a model of the fluidized bed polymerization reactor for linear low density polyethylene (LLDPE) production is developed using the Aspen Custom Modeler (ACM) to predict the polymer characteristics and flow behavior. The developed model is then integrated to the main process flow simulation in order to optimize the energy consumption in the polymer production process. The results show that the total energy requirement is reduced while maintaining the same polymer characteristics. [ABSTRACT FROM AUTHOR]

Thailand’s final energy consumption has been continuously increasing in the building sector. In terms of electricity consumption, this sector is the largest electricity consuming sector, and accounted for 57.9% of total electricity consumption in 2013. The fossil fuel consumption is dominated by liquefied petroleum gas within these sectors. Therefore, the fossil fuel and electricity demand satisfying the end-user requirement substantially affect the climate change especially the contribution of greenhouse gas (GHG) emission. Changes of GHG emissions depend not only on the economic development but also on population growth. Consequently, the aim of this paper is to evaluate and provide the long-term energy saving potential and the GHG mitigation by the implementation of Thailand’s Energy Efficiency Plan 2015 (EEP2015) during 2010-2036. The energy saving potential and environmental impacts are analyzed by using the Long-range Energy Alternative Planning system (LEAP). The evaluation of energy saving potential and environmental impacts, the residential sector is divided into three areas namely; Greater Bangkok, municipal, and rural areas. The commercial sector is divided into eight building types including offices, hotels, hospitals, department stores, schools, hypermarkets, condominiums, and miscellaneous. The business-as-usual (BAU) scenario is excluded the energy efficiency improvement. While, alternative (AL) scenario includes all existing measures in the EEP2015. In the residential sector, the highest energy consuming and GHG emission area is the rural area. In the commercial sector, offices contribute the highest GHG emissions. Energy demand and GHG emissions in both sectors will increase from 12.8 Mtoe and 43.2 Mt-CO 2eq in 2005 to 39.6 Mtoe and 131.1 Mt-CO 2eq in 2036 in the BAU scenario. The study discloses that EEP2015 can reduce the energy demand and the GHG emissions in both sectors by 19.1% and 31.2% in 2036, respectively. [ABSTRACT FROM AUTHOR]