bluuebunny/crossref_metadata_2025 huggingface dataset:
Ventilation mode effect on thermal comfort in a mixed mode building
Authors: Kim Jungsoo , de Dear Richard , Tartarini Federico , Parkinson Thomas , Cooper Paul
Published: October 2019

Between 2017 and 2018, we conducted a longitudinal field experiment in a mixed-mode ventilation building located in Wollongong Australia, with a particular focus on occupant thermal comfort and adaptive behaviour. This study investigated how different building operation modes i.e. air-conditioning (AC) and natural ventilation (NV), can have an impact on occupant perception of thermal comfort. Time-and-place matching of objective (physically measured indoor climate parameters, outdoor meteorological data, and building operational information) and subjective data (i.e. occupant survey questionnaires) enabled empirical investigation of the relationships between those parameters. The result of the analysis revealed that subjective perception of indoor thermal environment can be affected by different modes of building operation. Occupants were found to be more tolerant of, or adaptive to, the indoor thermal conditions when the building was in the NV mode of operation compared to the AC operational mode. The applicability of the adaptive comfort standard to the mixed-mode ventilation context was also discussed.
Improvement of thermal comfort in naturally ventilated classrooms by phase change material roofs in Taiwan
Authors: Chang S F , Hwang R L , Huang K T
Published: October 2019

This paper researched the effects of different types of insulated roofs, PCM roofs, and composite roofs on the overheating risk (Ihot
) in the naturally ventilated classroom in Kaohsiung, Taiwan. The EnergyPlus was applied to simulate the hourly operative temperatures in the classroom. The optimal melting temperature (tmp
) and thickness of the PCM roof, as determined from design day, were 36°C and 26mm, respectively, which are consistent with the results from year-round simulations. The design PCM roof could decrease the Ihot
by up to 64%, leading to an effect equivalent to the decrease by 25mm insulation. However, with thickness of PCM>26mm or insulation>25mm, their effect on the Ihot
was not significant. The changes of Ihot
was insignificant while tmp
of PCM roof in the range of 34-40°C, and Ihot
increased rapidly when tmp
>40°C. The effect of tmp
of composite roof on the Ihot
was not significant.
Design of online platform and visualization system based on three-dimensional spatial information for occupant satisfaction with indoor environment quality
Authors: Lee Jongwon , Kim Deuk-Woo
Published: October 2019

Prior evaluations of building energy performance have focused on quantitative performance based on mathematical models while overlooking the value of quality of residential life. The Post-Occupancy Evaluation (POE) method is regarded as an important component of the value judgment process for enhancing the quality of actual building performance. Accordingly, we developed a cost-effective open-source survey platform to collect data on occupant satisfaction. This study focuses on the evaluation indexes of indoor environment quality (IEQ) and conducted a pilot test. The difference of this platform compared with existing online survey systems is that the survey information is linked with the shape and spatial information of the building. This study’s online platform for surveying occupant satisfaction is expected to significantly reduce the time and costs required for conventional IEQ occupant satisfaction surveys. In addition, the collected survey responses are analyzed through a database and visualized as a prototype based on 3D spatial information, providing more intuitive feedback to the owner and occupants of the building.
Indoor environmental monitoring of residential buildings in Saudi Arabia, Makkah: a case study
Authors: Alaboud M , Gadi M
Published: October 2019

In Saudi Arabia, buildings require significant amounts of energy, especially during the cooling season, because of excessive air conditioning demands related to the high outdoor temperatures. Residential buildings consume more than 50% of electricity in the Kingdom of Saudi Arabia, where air conditioning loads represent 70% of the consumption. The main aim of the paper is to improve indoor thermal performance of existing residential buildings in Saudi Arabia, using Makkah as a case study. The methodology is to choose typical low-rise residential buildings to evaluate indoor thermal performance of existing residential buildings in Makkah, then calibrate this with the simulated results taken from thermal analysis software (TAS) to validate them, finally adding few energy efficiency measures to decrease the cooling load in the case study building. The result is expected to show similarity between the two results and also indicate that the energy conservation measures used can decrease the cooling load to as high as 34.5%.
Experimental setup and testing of an in-field system for real-time occupant feedback
Authors: Lassen N , Josefsen T
Published: October 2019

Thermal comfort and air quality in buildings have been found to be the 2nd and 5th largest sources of complaints among occupants in modern office buildings. In building operation, the determination of control setpoints is normally based on a combination of theoretical models and feedback from occupants. The feedback is most often unstructured and based on face-to-face information transfer, costing time for building operators and with no possibility for systematic learning over time. In practice, operating temperature ranges as small as 1-2°C are usually adopted in order to prevent complaints from occupants in office buildings. Research has however shown that narrow temperature ranges do not result in higher occupant satisfaction, and several researchers have proposed that control of buildings should be done based on continuous subjective feedback from the occupants in the building. This article covers the design and proof of concept for a non-intrusive system for continuous occupant feedback in offices. The system consists of a feedback terminal for capturing day-to day overall satisfaction with indoor climate, a smart phone based system for capturing personal comfort thresholds, and physical measurements of room temperature and CO2 level. Longitudinal tests were conducted in selected rooms in two buildings near Oslo in Norway, measuring a total of 20 office desks in regular use over 3-5 months. The findings indicate that this simple and inexpensive system collects information about the occupant’s perception of the indoor climate. Further work must be done to give this information value for building control and learning.
IEQ and energy improvement of existing buildings by prefabricated facade additions: the case of a student house in Athens
Authors: Ferrante Annarita , Fotopoulou Anastasia , Semprini Giovanni , Cantelli Davide , Ruggiero Silvia , Karalis Michalis , Efthymiou Chrysanthi , Papadaki Dimitra , Assimakopoulos Margarita-Niki
Published: October 2019

The aim of this paper is to evaluate and illustrate the energy saving potential and Indoor Environmental Quality (IEQ) performances of a façade addition on existing and low energy performing buildings. Different technical solutions are proposed and all IEQ indicators’ simulation results are presented for the case of a students’ building block of the 80’s located in Athens. The building is the demonstrator of the “Pro-GET-onE” Horizon 2020 project, that aims to demonstrate the attractiveness and the energy efficiency of a renovation strategy based on new façade additions combining inteGrated Efficient Technologies (GETs). The research project proposes the highest transformation of the existing building’s shell with external added volumes, which generate energy efficient buffer zones and at the same time increase the building’s volume (with balconies, sunspaces and extra rooms). This strategy gives also the possibility to increase IEQ performance, in different ways depending on the architectural solutions, the selected materials and the adopted technological solutions. As a general statement, the facade addition solution leads to an increase of the thermo-hygrometric conditions (both for the cold winter season and the summer period), of the facade sound insulation and consequently the acoustic comfort, and of the indoor air quality. The lighting and the visual comfort are a critical point due to the enlargement of the existing surface of the rooms: specific light enhancement techniques have been studied to optimize indoor light, therefore minimizing the drawbacks of façade expansions, and will be suggested for the final design of the case study. The detailed analysis of individual units (additions) led to the formulation of hypotheses for targeted energy retrofitting interventions in different options; with different scenarios of integrated RES technologies, these options have been analysed both separately and in combination, to assess the technical, the energy feasibility and the IEQ performance in each scenario.
Experimental evaluation of the cooling and heating dynamics for a vertical ventilation concept in a generic car cabin
Authors: Dehne Tobias , Westhoff Andreas
Published: October 2019

A low-momentum ceiling-based ventilation concept is compared to dashboard ventilation in a full-scale generic car cabin (GCC).The dimensions of the cabin correspond to the interior of a typical mid-size car. To provide different boundary conditions, representing winter and summer, the GCC is equipped with a jacket cooling/heating. Thermal manikins simulate the heat release and the obstruction of passengers. With the objective to verify the thermal comfort and the global heat transport characteristics in the GCC, the velocities as well as the air and surface temperatures are recorded. In the present study, the cooling and heating dynamics of the low-momentum ceiling ventilation are examined and compared to a simplified dashboard ventilation with regard to thermal comfort and heating/cooling efficiency. It is found that the cooling and heating dynamics of the low-momentum ventilation differ significantly in comparison with the dashboard ventilation. Overall the low-momentum ceiling offers several benefits regarding the thermal comfort and efficiency.
An approach to develop a green building technology database for residential buildings
Authors: Shen Jialei , Zhang Jianshun
Published: October 2019

Buildings consume approximately 39% of the total energy used in US, of which 53% is consumed by residential buildings. Besides, indoor air quality (IAQ) have significant impacts on occupant health since people spend on average around 90% of their time indoors. Nowadays, a great number of green building technologies (GBTs) have been developed and implemented in buildings for reducing energy consumption and improving IAQ. This paper proposes an approach to develop a green building technology database for residential buildings including their the technology’s feature and performance for energy saving and IAQ improvement under different building configuration and climate conditions. The GBTs are collected from case study buildings. For each study case, the GBTs are classified by the Virtual Design Studio (VDS) building assessment method. A local reference building is first defined for the region where the case building is constructed. Both forward-step evaluation of a proposed GBT to a reference building and backward-step tracking of the contribution of the technology to the case building are conducted. A scalability analysis is also conducted to understand the practical application of the performance parameters to other cases with different building design. EnergyPlus and CHAMPS-Multizone are used to analyse the energy and IAQ performance for each technology. The approach is verified by a case study of two single-family houses in US.
Appropriate technology to improve the condensation resistance of existing window
Authors: Lee Suin , seok Choi Gyeong , jung Choi Hyun , sik Kang Jae
Published: October 2019

The dilapidated windows in old buildings lead to not only energy loss but also condensation, which can cause damages to finish materials and structures, which can adversely affect the residential environment of residents. In the research, in order to prevent the occurrence of condensation, the airtightness performance improvement technology of window(Windbreak) and the thermal insulation performance improvement technology of window(Attached glazing) were selected. Then, these two technologies were applied to real old apartment houses for performance verification. TDR (Temperature Differential Ratio) was calculated by measuring the surface temperature of the window before and after the application of the two technologies, and the quantitative evaluation was performed by comparing the measured values. As a result, the condensation prevention performance was enhanced by about 17.69% result for the installation of the attached glazing and the windbreak. Especially, it was more effective in the lower part of the glazing where condensations mainly occurs.
Improving the indoor climate of the traditional Ottoman houses in the Medina of Algiers
Authors: Benchekroun Marwa , Chergui Samia , Ruggiero Francesco , Di Turi Silvia
Published: October 2019

The implementation of energy efficiency in historic buildings is limited and different parameters inhibit the improvement of microclimate conditions or energy performance. The aim of our research is to study the residential buildings of the old city of Algiers and to highlight the colonial and post-colonial transformations. The hygrothermal comfort is studied in order to identify a typical model of house having undergone transformations. This work requires a scientific and multidisciplinary approach integrating historical understanding, modern non-destructive inspection techniques and advanced experimental and numerical analysis methods (modelling and thermal dynamic simulation). The results show that in some cases of traditional houses, the transformations have been positive. The modification had a good functioning to modulate the variations of temperature and an indoor air quality allowing the occupants to profit from various zones of comfort. In other cases the undergone transformations generated enormous disorder resulting from discomfort situations. This work will provide adequate solutions to improve energy efficiency and sustainability for this residential heritage.
Concentration levels and impact factors of benzene series in Chinese dwellings
Authors: Yin Yihui , Hou Beibei , Pei Jingjing , Liu Junjie
Published: October 2019

In this study, a nation-wide field measurement has been carried out in Chinese residence to obtain BTEX(benzene series) concentration levels and characteristics. Concentrations of benzene series (benzene, toluene, xylene and ethylbenzene) indoor were sampled in 223 dwellings covering 5 climate zones in China during 2016.12-2017.12. The arithmetic mean concentrations of benzene, toluene, xylene and ethylbenzene were 6.78μg/m3, 17^g/m3, 17.68μg/m3 and 9.87μg/m3, respectively. Higher concentration of BTEX and higher standard limit were founded in China than that in other countries and organizations. We identify some reasonable sources for specific data group, impact factors on decoration year, frequency of smoking and cooking of benzene series concentration were studied. Toluene concentration decreased with increase of decoration year, and concentration of benzene concentration in smoking families were higher than that in non-smoking families. No direct correlation between cooking frequency and indoor benzene concentration were founded. This study also provided statistical data on benzene exposure in new decorated residences and a discussion on setting limit values for standard.
Analysing the effects of thermal comfort and indoor air quality in design studios and classrooms on student performance
Authors: Ranjbar A
Published: October 2019

This study aimed to explore the various effects of different ventilation modes on the thermal comfort and indoor air quality in design education environment. It also investigated the relationship between the ventilation mode and student performance. Thus, an experimental study was conducted in both studio and classroom environments, in Interior Architecture and Environmental Design Department at Bilkent University, Ankara, Turkey. CO2 concentration values, indoor air temperature and humidity values as the main parameters of thermal comfort and indoor air quality was measured in both winter and summer seasons under the three modes of ventilation: 1) without opening door and windows mode setting; (2) natural ventilation mode and (3) the HVAC ventilation mode achieved by the TROX school-air unit. Under these three different modes for both attention and concentration levels, 100 students from the winter season, 50 students from summer season for the classroom environment, and 20 students from the winter season, 16 students from summer season for the studio environment participated. Results were calculated in IBM SPSS 21 software separately for both seasons and three different ventilation modes. As a result, the experimental and performance results have shown that the HVAC unit mode achieved the most satisfactory indoor environment in both seasons and higher levels of student performance.
Usability and comfort in Canadian offices: Interview of 170 university employees
Authors: Ouf Mohamed , Tamas Ruth , O’Brien William
Published: October 2019

Increasing building automation to improve energy efficiency introduces a risk of reducing occupants’ perceived control and overall comfort. To this end, this paper presents a field study that used contextual techniques to explore the relationship between occupants’ perceived control and comfort, as well as their preferences for building automation. A total of 170 occupants in 23 Canadian university campus buildings were interviewed in their offices using semi-structured interviews. All interviews entailed verbally administering a survey while photographs were systematically used to identify the context of occupants’ interactions with building controls. Findings revealed that occupants’ perception of comfort was moderately correlated to their perception of control over their indoor environment. Occupants also showed an overwhelming preference for more control opportunities in their offices (e.g. operable windows and dimmable lighting controls). Conducting interviews in offices yielded many interesting anecdotes and enabled the researcher to identify contextual issues related to building controls’ accessibility, which may have been unnoticed otherwise. The findings of this research contribute to a broader debate within the research community about the appropriate level of building automation to optimize energy efficiency and occupant comfort.
Impact of essential-oil-based cleaning products on indoor air quality: From liquid composition to test emission chamber
Authors: Angulo Milhem S. , Verriele M. , Nicolas M. , Thevenet F.
Published: October 2019

As society has become aware of health hazards related to the exposure to chemicals, major efforts have been made to address indoor air current problematic. Consequently, popularity of “green” cleaning products has upsurge. These products are formulated with essential-oils relying on their anti-bacterial properties to improve indoor air quality. Indeed, essential oils might contain a hundred of odorous molecules, mainly terpenes and terpenoids (TerVOCs) which acts as antibacterial agents. Nonetheless, do essential-oil-based products really contribute to indoor air quality improvement? This study is addressed to evaluate emissions from the use of essential-oils-based cleaning products by various scale experiments. Firstly, a correlation of liquid composition from 7 natural cleaning products with their emission potentials has been investigated. Volatile fractions are evaluated by using micro-chamber testing. A total of 28 terpenes are quantified among products in the liquid form. Nevertheless, only 22 species are detected in gas samples with a yield ranking from 9.1 % to 99.8 %. Results do not verified a direct correlation between liquid mass and emitted concentrations of terpenes. Indeed, chemical affinities between terpenes and solvent matrix in product formulation are evidenced. Then, 4 products from different cleaning purposes have been selected for emission evaluation in a test chamber of 1-m3. Product application process are correlated to real case scenario regarding applied quantity and loading factor. Emitted terpenes and carbonyl compounds are quantified by off-line and on-line chromatography measurements. Results evidenced that peak concentrations from terpenes reached up to 1.5 h after cleaning activity. Major compound emitted concentration range from 121 to 152 μg/m3, in the test chamber, for different product categories. Specific emission dynamic is evidenced for formaldehyde, in where continuous increasing concentration is revealed due to the presence of formaldehyde releasers. This study contributes to further assessment of exposure hazards related to cleaning activities.
Indoor air quality performance in air-conditioned museum gallery
Authors: Sulaiman R , Kamaruzzaman S N , Yau Y H
Published: October 2019

The performances of IAQ in Malaysian museum galleries have not been well investigated. As a hot and humid country, air conditioning (AC) systems are used in enclosed galleries. Improper AC systems may affect IAQ levels as they may not only affect people but also artefacts deterioration. Selected IAQ parameters were measured in selected museum galleries in Peninsular Malaysia by using active sampling with multiple sensors at several points continuously. Results on average values for indoor temperature and carbon dioxide complied with people and artefact threshold level. However, air velocities were far below the recommended level. Visitors’ influx influenced CO2 levels but did not affect the resuspension and reposition of PM1. It started to increase when the CO2 decreased. This highlighted the contribution of this research as guideline for IAQ in museum is only up to the concentration of PM2.5. Poor Va and the existence of PM1 were expected due to the inefficiencies of the AC systems as higher cooling capacity did not influence better IAQ performance. It was concluded that, IAQ performance in the selected galleries did not perform well due to poorly ventilated cool air supply and improper layout of air inlets due to the ceiling heights and hanging decorative ceiling.
Energy consumption for domestic hot water use in Norwegian hotels and nursing homes
Authors: Taxt Walnum Harald , Sørensen Åse Lekang , Ludvigsen Bjørn , Ivanko Dmytro
Published: October 2019

Domestic Hot Water (DHW) production constitutes a significant proportion of the energy demand of modern buildings, and as the building envelope is improved the share increases. This article discusses the results from a measurement campaign in Norwegian hotels and nursing homes. The energy demand for DHW and distribution heat losses for 3 hotels and 3 nursing homes are shown. The results show that number of bedrooms is a better parameter for describing DHW consumption than sqm of heated floor area. There are large variations in the measured distribution losses, mainly due to malfunctioning of the hot water circulation system. For nursing homes, the measured energy consumption is significantly lower than the normative profiles, which can have large impact on the requirements for the design of the building heating system. For hotels, the measured energy consumption is in the range of the normative profiles.
Application of Comfort Range Control logic for thermal comfort and energy saving in VRF system
Authors: Park Sohyun , Kim Joowook , Song Doosam
Published: October 2019

In Korea, in order to reduce building energy, the policy applying insulation standard of passive house level to new buildings from 2017 was established. However, the concept of passive house applied in the Central and Western Europe area is feared to increase the cooling load in hot and humid areas in summer like Korea. Therefore, we propose a control logic for reducing the cooling energy in summer while maintaining occupants’ thermal comfort that can apply to VRF system installed in passive buildings. In this paper, Comfort Range Control logic based on ASHRAE Comfort Chart for occupants’ thermal comfort and energy saving was applied to VRF system in the actual office space of passive building in Korea. The indoor environment and energy consumption according to the conventional control method, Set-Point Control, and Comfort Range Control proposed in this study were analyzed by field measurement.
A robust chiller sequencing control method for enhancing cooling supply reliability and energy efficiency
Authors: Liao Y D , Cai Z B , Fang Z S
Published: October 2019

Control of heating, ventilation and air-conditioning systems (HVAC) has become an active area of research due to the significant energy expenditures and maintenance cost. Among the various controls of HVAC systems, chiller sequencing control is of great importance for multi-chiller plant to keep cooling reliability, system stability and energy efficiency. However, conventional chiller sequencing control usually lacks consideration of system stability and the accessional cost caused by the sequencing actions. Especially, those short-time or unnecessary sequencing actions become the main reason for operators to shut down automatic control. To enhance the reliability of chiller sequencing control, a robust hybrid predictive control is developed. This control is developed based on the typical total cooling load-based control and use an ARX prediction model to double check necessity of the sequencing actions. Case studies were carried out on a TRNSYS dynamic simulation with the configuration data from a real secondary school. Results showed that the switch number can be reduced more than 20% and operation cost can be reduced up to 4.25% without scarified in thermal comfort and energy efficiency.
Characterization of heat load profiles in buildings and their impact on demand side flexibility
Authors: Walnum H T , Justo Alonso M , Clauß J , Lindberg K
Published: October 2019

A data set of heat load measurements for 197 buildings from different building categories (apartment blocks, hotels, nursing homes, offices and schools), have been analysed to evaluate the potential for peak shaving. A moving average filter is applied to investigate how smoothening of the load profiles can reduce the peak loads. It is shown that for short term peak shaving, apartment blocks and hotels have the highest potential (around 8% for a two hour period), while for longer term peak shaving, the results are more even for all the building categories. Schools stand out, with a large difference in heat consumption between inside and outside opening hours, leading to a large flexibility potential on daily basis, but this would require a large amount of stored energy. As it is difficult to control, and thereby reduce the peaks for unknown loads, a prediction model is applied to the data, to analyse the predictability. It is shown that the peak shaving potential is reduced 90-30 % when analysing only the predictable loads. The biggest difference is in the short-term potential for apartment blocks and hotels, while difference is smaller in the long-term (24-hour) peak shaving potential.
Monitoring and Evaluation of Nearly-Zero Energy House (NZEH) with Hybrid HVAC for Cold Climate – Canada
Authors: Demirezen G , Ekrami N , Fung AS
Published: October 2019

A Nearly Zero Energy Home (NZEH) in Strathroy, Ontario, Canada was monitored and studied to evaluate its performance for both heating and cooling seasons. The house is a new built and is equipped with an electric-natural gas hybrid spacing heating system. A high efficiency natural gas furnace and an electric air source heat pump (ASHP) were coupled to meet the space heating demand of the house. The house also benefits from on-site renewable energy generation (solar PV). The original system was controlled by a simple switch over thermostat that drives furnace or ASHP based on the outdoor temperature as a single decision-making factor. The system then was upgraded with a cloud based Smart Dual Fuel Switching System (SDFSS) controller that considers time-of-use (TOU) pricing, fuel cost, weather forecast, and equipment efficiencies and capacities. This multi-variable decision-making process defines an optimal schedule for the hybrid system to run more efficiently and more economically. A detailed monitoring system, including sensors, meters, and data acquisition system, was installed to collect all required information at a 2-minute interval. The furnace and ASHP were studied separately to verify their capacities and efficiencies. Then the overall hybrid system and its controller were monitored to identify its effectiveness. A complete model of the house and the hybrid system were developed and validated with experimental data. Thereafter, the system was run by the SDFSS controller. All of these scenarios were compared against each other and benchmarked. In addition, the factors affect indoor air quality (IAQ) were studied in detail. The preliminary result has shown that SDFSS controller provides a cost effective, feasible, cleaner and healthier IAQ options to run the hybrid system in a NZEH.
Cost-efficient Nearly Zero-Energy Buildings (NZEBs)
Authors: Erhorn-Kluttig H , Erhorn H , Illner M , Engelund Thomsen K , Wittchen K , Mørck O , Sanchez Mayoral Gutierrez M , Zinzi M , Mattoni B , Fasano G , Šijanec-Zavrl M , Jacimovic M
Published: October 2019

The next level of energy performance of new buildings within the European Union will be the Nearly Zero-Energy Building (NZEB). A lot of work has been spent on pilot and demonstration buildings on this and even higher energy performance levels throughout many EU countries. However, most of the high performance buildings realised so far result in additional investment costs when compared to the current national minimum energy performance requirements. The considerably higher investment costs are one of the main barriers to the early application of the NZEB-level in Europe. The EU Horizon 2020 project CoNZEBs works on technical solution sets that result in lower investment costs for NZEBs, bringing the costs close to those of conventional new buildings. The project focus is on multi-family houses. In each of the four participant countries Germany, Denmark, Italy and Slovenia a team of researchers is analysing which sets of market-ready technologies at the building envelope, the services systems for heating, domestic hot water, ventilation and cooling (where required) in combination with renewable energy systems can fulfil the NZEB requirements at lower costs than those incurred by the national mainstream NZEB application. Additional efforts are being spent on the life-cycle costs and the life-cycle analysis of the solution sets, as well as on the impact of future developments of primary energy factors, energy costs and technology efficiencies. Since details of the CoNZEBs work are presented in several additional papers, this document gives an overview of the different tasks and results that are available so far.
A simulation study on the performance of double skin façade through experimental design methods and analysis of variance
Authors: Jankovic A , Goia F
Published: October 2019

Systematic studies of the thermal fluid dynamic behaviour of building envelope systems through experiment analyses is limited by the relevant amount of time and high costs necessary to carry out a relevant number of tests covering all the possible configurations. Building simulation can be used as a tool to support the design of the experiments, i.e. to test, in a parametric way, different configurations to highlight the main trends, and therefore select the most relevant cases to be tested experimentally. Such a preliminary activity to maximize the effectiveness of the experiments may relates to both parametric analysis of indoor/outdoor boundary conditions, as well as parametric analysis of building envelope configurations. In the framework of a research project on double skin facade (DSF) systems where experiments are planned on a full-scale prototype, a model of a DSF is realized in a whole building energy software tool, and used to carry out a preliminary sensitivity analysis, by means of orthogonal array method and analysis of variance. Simulations were carried out in EnergyPlus, using the Airflow window module, and under steady-state conditions, a series of variables (cavity depth, venetian blinds tilt angle, airflow rate) have been investigated to assess their impact on the heat extract through the ventilation air and the total heat transmission between the outdoor and indoor environment. The results show that the main driver in the performance of DSF considering net heat rate transfer is the irradiation impinging on the façade in terms of boundary conditions, and coherently, the shading device is the feature that most affects the performance of the system among the characteristics of a DSF.
Machine learning algorithms for classification of boiler faults using a simulated dataset
Authors: Shohet Rony , Kandil Mohamed S , McArthur J J
Published: October 2019

Building performance has been shown to degrade significantly after commissioning, resulting in increased energy consumption and associated greenhouse gas emissions. Continuous Commissioning using existing sensor networks and IoT devices has the potential to minimize this waste by continually identifying system degradation and revising control strategies to adapt to real building performance. Due to its significant contribution to GHG emissions, building heating, particularly gas boiler systems are critical systems for detecting decreased performance. A review of boiler performance studies has been used to develop a set of common faults and degraded performance conditions, and these have been integrated into a MATLAB Simulink emulator to create a labelled dataset with approximately 27,500 cases for training and testing boiler fault classification models. Classification algorithms such as K-nearest neighbour, Decision tree, Random Forest and Naïve Bayes have been tested and the results show that decision tree methods gave the best prediction (97.8% accuracy) followed by Random forest (95.0%) and KNN for K = 3 (88.1%). Naïve Bayesian and KNN for K = 9 classification both gave poor results.
Research on active solar energy comprehensive utilization system for Tibetan rural dwelling
Authors: Feng Xu , Yuan Deng , Hongqiang Li , Yimo Liu
Published: October 2019

In view of the problem that in rural Tibet the solar radiation is too strong and the deep plan of traditional residential buildings has resulted in poor natural lighting, the author proposed an active natural daylighting system. The system makes full use of the abundant solar energy resources in Tibet without changing the existing structure of the building. It improves the living environment and the indoor comfort by four working modes, including light reflection guidance, thin film amorphous silicon photovoltaic power generation, Synergistic application of lighting and shading and building insulation. The research results show that with this system, the indoor illumination time extends by 3 hours and the average indoor light depth increases by more than 3.5m. Meanwhile, 119.58 degrees’ electric power can be provided per year and the building thermal insulation performance can be improved. This system has broad application prospects in rural areas of Tibet and may inspire new ideas for other relevant design.
Energy and exergy analysis of waste-water heat recovery in a multi-family residential complex
Authors: Kayo Genku , Shukuya Masanori , Martinac Ivo
Published: October 2019

This article provides an approach to analysing the energy and exergy efficiency of a waste-water heat recovery system. The system studied is installed in a multi-family residential complex in Stockholm, Sweden. The heat recovery unit in question consists of eight coaxial, counter-flow heat-exchangers connected in parallel, with waste-water flowing through the internal pipe and cold brine (propylene glycol 25%) ducted through the external pipe. The analysis was carried out based on data collected by a building monitoring system (BMS) during five winter months (heating season). The energy analysis (using average hourly values) showed that on average 10.7 kW (Span: 1.1 - 38.7 kW) of waste-water heat was delivered to the cold brine. On the other hand, the exergy analysis (using the same data) showed that on average 12% (Span: 3 - 24%) of the exergy contained in the waste-water was delivered to the cold brine, while on average 76% (Span: 60 - 88%) was consumed during the process. Access to accurate and detailed performance measurement data was found to be essential for analysing the exergy and energy performance of the heat recovery system. In conclusion, this article demonstrates that it is vitally important to consider both the first and second laws of thermodynamics to achieve a wholesome understanding of heat recovery from waste-water systems.
Tuning approach of dynamic control strategy of temperature set-point for existing commercial buildings
Authors: Afroz Zakia , Shafiullah GM , Urmee Tania , Higgins Gary
Published: October 2019

Indoor environmental parameters especially the air temperature have substantial effect on energy consumption in commercial buildings and indoor thermal comfort. This study presents a tuning approach of dynamic control strategy of temperature set-point with a view to improving occupants’ thermal comfort while simultaneously minimizing energy consumption. To determine optimum temperature set-points in response to ambient conditions, this study investigates the thermal comfort conditions of a commercial building based on real time series data. To quantify thermal environmental conditions for human occupancy, this study uses the graphical comfort zone method proposed by ASHRAE Standard 55-2017 through a rigorous analysis. Based on this analysis the study narrows down the comfort range in the context of seasonal variations and proposes tuning the Master Temperature Set-Points (MTSP) with 4.8°C variable linear band between upper and lower temperatures dependent on a simple algorithm. This re-setting strategy of temperature set-point ultimately offers extended lower and upper boundary limit for variable linear band. Extension of linear band for MTSP reduces the gap between temperature set-point and outdoor temperature which ultimately offers less heating and cooling energy consumption. Results show that implementation of this proposed approach would lead to monthly 2707.94 kWh energy savings either from heating or cooling or both during winter and summer season.
Effects of increasing urban albedo in the Greater Toronto Area
Authors: Zahra Jandaghian , Umberto Berardi
Published: October 2019

Increasing surface reflectivity decreases the skin and air temperature, which potentially reduces cooling energy demands. The state of the art online numerical Weather Research and Forecasting model (WRF) is used to investigate the effect of increasing albedo in Toronto, Ontario, during the 2018 heat wave period (July 2nd through July 5th) on urban climate and building energy consumption. The study couples the WRF with a multi-layer of the Urban Canopy Model (ML-UCM) and Building Energy Model (BEM). The ML-UCM is a part of the land-surface parameterization to predict the heat and moisture fluxes from canopies to atmosphere. The BEM is coupled with Building Effect Parameterization to predict the energy consumption of buildings. BEM simulates the effect of heat generation from buildings on urban climate. The reflectivity of roofs, walls and roads are increased from 0.2 to 0.65, 0.60 and 0.45, respectively. Albedo enhancement leads to a decrease in air temperature by around 1°C and an increase in wind speed which induce a reduction in skin temperature. The combined effect of decreased solar heat gain by buildings and decreased air temperature reduced the energy consumption of HVAC systems by 3-5%, confirming the positive effect of increasing the albedo on urban climate.
A systematic methodology for energy modeling improvement of cross-ventilated buildings in dense urban areas
Authors: Shirzadi Mohammadreza , Mirzaei Parham A. , Naghashzadegan Mohammad
Published: October 2019

Cross-ventilation strategy is an efficient and reliable method, which has been used in modern zero-energy buildings and traditional buildings for reducing building energy consumption and improving indoor air quality. The accuracy of current models based on building energy simulation (BES) and computational fluid dynamics (CFD) are questionable in dense urban areas. Hence, in this paper, a systematic methodology is introduced aiming to improve the energy modeling accuracy of cross-ventilated buildings in urban areas. The methodology comprises of three main steps for validation metric definition, CFD model calibration, and BES model calibration. The CFD model calibration is based on the stochastic optimization of the closure coefficients while BES model calibration is carried out by using results of the calibrated CFD model and approximation models. The proposed method was applied to a small multi-story building surrounded by eight buildings in a neutral atmospheric boundary layer (ABL) in Rasht city, Iran. According to the results, the accuracy of the modified BES model is 60% higher than the default BES model in prediction of the cross-ventilation energy-saving potential.
Energy and environmental analysis of urban environment: methodology and application of an integrated approach
Authors: Salamone F , Belussi L , Danza L , Nunzio Antonello Di , Ghellere M , Meroni I
Published: October 2019

The new vision of Smart Cities drives policies regarding sustainability of urban environment in terms of reducing consumption, environmental impacts and improving energy efficiency and safety of building sector. The mutual interaction between buildings and the surrounding built environment can affect all these fields. In particular, the paper investigates this interaction in order to analyse the energy behaviour of buildings at urban scale and the effect on the outdoor comfort. To reach this goal a multi-level and multi-purpose model was developed based on a synergic and integrated bottom-up approach for both energy efficiency and outdoor comfort analysis. The energy analysis is based on the identification of reference buildings with known energy performances, defined sing information available at Public Authorities, statistical studies and data from field surveys. A multi-level parametric approach used for the outdoor comfort analysis allows to identify the Universal Thermal Climate Index (UTCI) and the related stress level of the district starting from the environmental data available at rural station. The model allows the estimation of the current energy and environmental behavior of the built environment and identifies possible renovation scenarios.
A cost-effective building in the Mediterranean area: Passivhaus design and energy modelling
Authors: Russo P. , Colaci De Vitis G. , Gentile G.
Published: October 2019

An actual cost-effective approach to high performances building in the Mediterranean area has been still missing: this project was carried out applying the Passivhaus approach to several building solutions using PHPP 9. Integrated design approach made possible a cost-effective building: all the designers involved were forced to work together and PHPP was used as a design tool, starting in the very first phases of the process. The initial concept was unfortunately far from a simple form and there were a lots of thermal bridges. The majority of those were completely solved, however, we decided not to design a thermal-bridge-free detail in some cases, but simply minimize the impact of the losses and verify internal surface temperatures. Triple-pane for windows would have certainly minimize the heating demand, but a low-e double-pane is cheaper and also maximize the solar heat gains. In summer, solar gains would be a real problem in this climatic zone and for this reason shading systems were optimized to offer protection in summer and large gains in winter. The whole design process was simultaneously followed by real time energy calculations with PHPP as a design tool. A compact unit for each apartment provides ventilation, heating, cooling and hot water production. Really low heating and cooling demands made possible to heat and cool only with a post treatment after the recovery on the airflow.
Study on reducing the environmental burden of a government building with an energy saving system
Authors: Sonoda Yuya , Kuwahara Ryoichi
Published: October 2019

This study aims to grasp the energy consumption of the government buildings currently being planned. The target building is the new government building in U City Japan, which is planned as a zero energy building for ZEB ready. In addition, considering the latest equipment to be introduced to the government building, energy simulation was performed using the Building Energy Simulation Tool (BEST) program. Simulation results revealed that the annual primary energy consumption was reduced by 30% below the reference value. In the future, the energy consumption will be further reduced by examining the methods for operation and control of the heat source equipment.
Influence of microclimate boundary conditions in net zero energy settlements on HVAC efficiency
Authors: Grazia Matteo Di , Piselli Cristina , Pisello Anna Laura
Published: October 2019

Net zero energy buildings (NZEB) represent reality of new constructions in Europe for environmentally sustainable energy efficiency. The shift to net zero energy settlements represents a further opportunity to achieve extra-energy saving, thanks to utilities sharing, renewables optimization, and microclimate mitigation. This last aspect concerns the opportunity to improve settlements outdoor microclimate conditions in both hot and cold seasons, in a variety of climate conditions, with the purpose to improve occupants’ wellbeing. At the same time, microclimate mitigation at inter-building scale may also involve relatively less severe boundary conditions able to reduce both cooling and heating demand of buildings and better working conditions for HVAC systems, e.g. heat pumps and air-to-air heat exchangers. This extra-energy saving, achievable with no extra costs, may represent an interesting opportunity to be taken into account in net zero energy settlements design and construction. This study analyzes this energy saving in a net zero energy settlement in Italy, built thanks to an on-going Horizon 2020 project. The influence of microclimate mitigation strategies is assessed in terms of energy saving benefits for the heat pump working conditions. Results demonstrate that this further benefit represents a non-negligible, environmentally sustainable, strategy for energy efficiency of NZEB in new inter-building scale developments.
HN_ZEB technologies applied for the cosntruction of On Plein Air tourist villages and Standard Sustainable Production
Authors: Pascalis Roberto De , Palmisano Francesco , Clori Francesco , Uva Rocco Luciano , Martano Sergio
Published: October 2019

The “Glamor On Plain Air” holiday system, combined in the luxury and ultra-luxury sector, represents a new large area of interest towards which the qualified tourist market is strongly oriented. One of the tourist assets is constituted by the sustainability and compatibility of the holiday in a system strongly oriented towards the circular economy, the containment of consumption as well as the significant respect for nature and the containment of the environmental impact towards a reduction of global warming. From this point of view, the use of HN_ZEB technology for the restructuring or design of this type of tourist facilities that require particular and exquisite tricks in every aspect of the project is perfectly framed, precisely to be included in the exclusive lists of relative use at international level.