bluuebunny/crossref_metadata_2025 huggingface dataset:
A personal visual comfort model: predict individual’s visual comfort using occupant eye pupil size and machine learning
Authors: Cen Lingkai , Choi Joon-Ho , Yao Xiaomeng , Gil Yolanda , Narayanan Shrikanth , Pentz Maryann
Published: October 2019

Lighting, as a significant component of indoor environmental quality, was found to be a primary contributor to deficient indoor environments in today’s workplace. This resulted from the fact that current guidelines are derived from empirical values and neglect the prevalence of computer-based tasks in current offices. A personal visual comfort model was designed to predict the degree of an individual’s visual comfort, as a way of evaluating the indoor lighting of the environment. Development of the model relied on experimental data, including individual eye pupil sizes, visual sensations, and visual satisfaction in response to various illuminance levels used for tests of six human subjects. The results showed that (1) A personal comfort model was needed, (2) the personal comfort model produced a median accuracy of 0.7086 for visual sensation and 0.65467 for visual satisfaction for all subjects; (3) To develop a prediction model for the sample group, the Support Vector Machine algorithm, outperformed the Logistic Regression and the Gaussian Naïve Bayes in terms of prediction accuracy. It was concluded that a personal visual comfort model can use a building’s occupant’s eye pupil size to generate an accurate prediction of that occupant’s visual sensations and visual satisfaction that can, therefore, be applied with lighting control to improve the indoor environment and energy use in that building.
Building Energy and IAQ improvement by Coupled Model
Authors: Heibati Seyedmohammadreza , Maref Wahid , Saber Hamed
Published: October 2019

The building performances are related to Energy Efficiency and Indoor Air Quality (IAQ). Modeling is one of the best accurate tools for measuring the building performance. Nowadays, Energy Efficiency and IAQ are modeled individually for buildings. Improvement strategies in both areas are analyzed separately. The fundamental problem in Energy and IAQ modeling is related to interaction to each other. This problem makes the modeling results unrealistic to the building performance solutions. To avoid this problem, in this current research, Energy and IAQ models are coupled simultaneously as a new co-simulation method. EnergyPlus and CONTAM are used as Energy and IAQ models, respectively. With the co-simulation method, these two models are coupled together. The method is based on the exchange of control variables between both models dynamically and simultaneously. As a result, the exchanges of temperature and air flow variables are corrected. The verification of the new model is based on the comparison of the simulation and analytical results of temperature and air flow variables. In the next step, this new coupling-co-simulation method for a townhouse building is done in two cases: a leaky and a tight building envelopes. Both cases are compared in two types of ventilation systems: infiltration only, and exhaust only. At this point, the simulated air change rates, gas energy use, and particles concentrations are compared for each case. Finally, the necessity of the accuracy of this new method is concluded.
Field measurement on the particle concentrations and exposures in five residential buildings in Korea
Authors: Kang Kyungmo , Kim Hyungkeun , Gyu Lee Yun , Kim Taeyeon
Published: October 2019

This study measured five apartments in the Daejeon. There is higher fluctuation for ambient air particle conditions. The average PN (particle number) concentrations was 5.2x108/m3. There are differences between five sites because of fluctuation for ambient air conditions. Particle concentration has different each occupant schedule. I/O ratios were different by occupancy schedules. Indoor particles exceeded 0.7 μm was significant emitted indoor activities. This result comes from two reasons. 1) Penetration by envelopes. 2) Indoor sources by occupants’ activities. PN decay rate (a+k) were 0.49-4.29 h−1 during indoor peak events. Total emitted particles (σ) was 0.0136.15 x 1013 particles per events. The cooking generated PN were wide range because of different event conditions. The ventilation rate is not enough to remove particles.
Development of numerical heat and mass transfer model for predicting total heat exchange performance in Energy Recovery Ventilator
Authors: Sotokawa H , Kameishi K , Chung J , Yoo S , Ito K
Published: October 2019

An energy recovery ventilator (ERV) is a widely used equipment that can recover sensible and latent heat. To improve its performance, it is essential to understand the heat and moisture transfer mechanism in the ERV. Against this background, overarching objectives of this study are to develop mathematical/numerical models for predicting and clarifying the hygro-thermal (i.e. heat and moisture) transfer mechanism in the heat exchange element of the ERV in terms of (i) simplified model for sensitivity analysis, and (ii) comprehensive model to integrate hygro-thermal transfer equations with computational fluid dynamics (CFD) analysis. Toward this end, we conducted fundamental experiments to measure temperature, humidity, and enthalpy exchange efficiencies in the scale-down ERV unit model, and then, numerical analyses were conducted according to the experimental scenario. As results of this study, we confirmed the reasonable prediction accuracy of our proposed numerical models for predicting total heat exchange performances.
RELaTED, decentralized & renewable Ultra Low Temperature District Heating, concept conversion from traditional district heating
Authors: Lumbreras Mugaguren Mikel , Garay Martínez Roberto , Sánchez Zabala Víctor
Published: October 2019

District Heating (DH) are a very efficient system for heating in urban areas and they are considered as key elements for the de-carbonization of the European Cities. High performance levels and low operational energy costs are part of the identity of these heating networks. The reduction of supply-line temperatures allows the possibility to introduce new low-grade and renewable source energy production, reducing dependence on fossil fuel-based energy plants. Moreover, heat-losses in distribution pipelines are also reduced, since the gradient temperature between supply line and ambient temperature is reduced. Operation of decentralized & Ultra Low Temperature (ULT) systems may adapt for the introduction of weather-dependent, distributed heat sources such as solar systems. Furthermore, although very dependent on local availability, waste heat streams from commercial and industrial installations are also considered because of the stability of heat supply all year round, resulting in minimally carbon intensive processes. Regarding building features, the reduced heat load derived from the transition from current buildings to Nearly Zero Energy Buildings (NZEB), RELaTED allows for the novel concept called prosumer, where buildings can deliver energy to the grid from decentralized energy sources installed in the building. In RELaTED, different subsystems are being developed by different industrial partners, to prove their efficiency in 4 real demonstration sites: Tartu (Estonia), Belgrade (Serbia), Vinge (Denmark) and Iurreta (Spain). A 3-FS (3-Function Scheme) DH substation that permits buildings to become prosumers. Two types of solar collectors, one is an all polymeric glazed collector and the second one is an unglazed collector, both as components of Building Integrated Large Solar Thermal Systems (BILSTS) solar loop. Finally, a reversible and high efficiency heat pump for domestic hot water is being developed. In this paper, an approach to ULT concept is studied, including transitory phases of the conversion.
Triple function substation and high-efficiency micro booster heat pump for Ultra Low Temperature District Heating
Authors: Lumbreras Mugaguren Mikel , Garay Martínez Roberto , Sánchez Zabala Víctor , Korsholm Østergaard Kasper , Caramaschi Matteo
Published: October 2019

District-Heating (DH) covers around the 9% of the total heat demand in the EU, with a proven highperformance levels and low operational costs. DH may suffer adaptations in order to maintain competitiveness with individual heating systems. The most important one is the reduction of supply temperatures up to 50°C, emerging the concept of Ultra Low Temperature (ULT) DH. ULT DH allows the transmission and distribution heat losses minimization, since heat losses are proportional to the temperature-gradient between supply line the ambient, increasing overall system performance. Furthermore, enables the integration of low-grade energy sources with low marginal costs, such as solar thermal energy or waste heat from industrial and commercial buildings. This study presents the combination of a novel 3 function-scheme (3FS) substation and a micro booster heat pump for domestic hot water. The novel design of the substation allows different operation modes between the grid and the building according to the temperature level and demand range every moment. Regarding the microbooster, this unit is used directly to lift the temperature of the domestic hot water (DHW), so that risk of legionella is avoided and that the required comfort temperature is reached. Preliminary test for the energy performance of the booster heat pump was measured on serially produced units according to tapping profiles and methodologies of standard EN16147. DHW coefficients of performance of 5.2 and 8.5 were measured for heat source supply temperatures respectively of 25 and 40 °C and return temperatures of 22 and 30 °C. This paper explores the possible operational modes of a 3FS in combination with a Building Integrated Solar Thermal System (BISTS) and a Microbooster heat pump.
Heat analysis for energy management in neighbourhoods: case study of a large housing cooperative in Norway
Authors: Sørensen Å L , Lindberg K B , Walnum H T , Sartori I , Aakenes U R , Andresen I
Published: October 2019

As a basis for energy management in apartment blocks, this paper characterises heat use in a large housing cooperative in Norway, with in total 1,058 apartments. Heat measurements with hourly resolution are available from 20 heating substations. Average specific heat delivery is 139 kWh per heated floor area. A linear regression model is described, modelling specific heat delivered to the apartments. Models are also used for separating heat to domestic hot water (DHW) from the total heat delivery, with a modelled DHW heat delivery of 34 kWh/m2. Daily heat load profiles are presented, for delivered heat during weekdays and holidays in the annual seasons. The study shows a potential for shifting heat loads in time on a neighbourhood level.
Experimental and numerical investigation of a thermal storage medium for ground source heat pump applications
Authors: Mwesigye A , Nguyen H V , Salt D , Daneshazarian Reza , Dworkin S B
Published: October 2019

As a means of improving performance and alleviating thermal imbalance issues associated with ground source heat pump systems, ground thermal energy storage is becoming increasingly appealing. Moreover, an efficient means of transferring energy from the borehole to the surroundings is crucial. In this paper, an experimental and numerical investigation of the performance of a thermal storage medium for ground source heat pump applications is presented. A thermal storage tank of 1 m diameter and 1.5 m height equipped with temperature sensors at different radial positions and depths was used. It incorporates a 150 mm-dimeter steel pipe in which a 25.4 mm u-shaped pipe is placed to emulate a borehole. A numerical model was developed using a finite element-based approach and validated with the obtained experimental data. Different bentonite-sand mixtures with varying thermal conductivities were considered inside and around the emulated borehole. A reduction in the tank temperature difference of about 57% was achieved by using bentonite-sand mixtures inside the borehole and around the borehole (in the tank) compared to using only bentonite inside the borehole and sand around the borehole. Results further show that the heat transfer performance increases by about 320% with the use of the bentonite-sand mixtures compared to the separated bentonite and sand arrangement. Moreover, the potential for energy storage with phase change material around the emulated borehole has been demonstrated.
Performance of VRF systems based on large scale monitoring
Authors: Liu Hua , Qian Mingyang , Yan Da , Berardi Umberto
Published: October 2019

Variable Refrigerant Flow (VRF) systems are refrigerant systems, which are generally comprised of an outdoor unit serving multiple indoor units connected by a refrigerant piping network. It is important to evaluate the performance of VRF systems, which can help the design and operate of VRF systems. Performance test done by manufactory can reveal the performance of VRF systems in designed conditions. However, it is hard to reveal effective performance in real buildings. The field test is complicated compared with the test in the laboratory and can only conduct on typical samples rather than large scale samples. However, typical samples are not enough for reflecting the performance of large scale VRF systems samples. A simple method of evaluating the performance of large scale VRF systems samples is necessary. This paper proposed and calculating model for electricity consumption and cooling demand of VRF systems based on measured operating data in the laboratory. The paper used the calculating model combined with 344 samples operating data from real residential buildings to calculate the performance of a large scale VRF. This paper analyzed the VRF systems’ performance with different influencing factors such as climate zones, cooling duration and outdoor temperature for the recommendation for VRF systems’ designing and operation.
Residential dual core energy recovery ventilation system for ventilation of northern housing
Authors: Ouazia B , Won D. , Arsenault C , Li Y
Published: October 2019

Heat/energy recovery ventilation systems are types of HVAC that can reduce energy consumption and improve the ventilation rate of housing in cold climates. Their performance achieved to date has been inadequate due to equipment failures (freezing of cores, noise, etc.). Freezing of cores is common in extremely cold climates. Single core HRV/ERV units are usually equipped with defrost strategies such as recirculation of exhaust stale air across the heat exchanger and back into the supply air to the house. These defrost strategies can undermine ventilation standards (ventilation rate requirement not being met during recirculation). This paper presents a rigorous investigation on the performance of dual core energy recovery system that provided a continuous ventilation rate at outdoor temperatures below -10°C without frost protection. The dual core ERV had higher apparent sensible effectiveness (up to 12% more) and apparent total effectiveness (up to 9% more) than a conventional single core ERV. It showed no sign of frost problems after four weeks of winter testing, continuously provided outdoor air without stopping to defrost, unlike the conventional single core ERV which required up to 7.5 hours defrosting per day, and also provided a higher supply air temperature (up to 3°C) to indoors with a total whole-house energy saving of 4.7%.
Study on the heat transfer performance of the ceiling radiant panel
Authors: Ichikawa Yuki , Kuwahara Ryoichi , Sato Hideki
Published: October 2019

The purpose of this study is to acquire data to examine the design method of radiant air conditioning in Japan. The radiant panels were installed in the population weather chamber, and the convective heat transfer coefficient and the radiant heat transfer coefficient on the upper side and the lower side of the radiant panel were experimentally calculated. As a result of this experiment, the radiant heat transfer coefficient was larger than the convective heat transfer coefficient during cooling and heating. In addition, CFD simulation of the thermal environment and airflow in the environmental control chamber was conducted. From the simulation results, it found that there was almost no temperature unevenness in the environmental control chamber, and the air flow was very small. There were differences in the comparison between the experimental values and the analysis values of the vertical temperature distribution.
Performance evaluation of Active Chilled Beam under cooling operation in real office conditions in a high-performance building
Authors: Upadhyay Rohit , Mora Rodrigo
Published: October 2019

This study investigates the operation of Active Chilled Beam under cooling operation in single occupant office in a high-performance LEED Gold Building at the British Columbia Institute of Technology in Vancouver. The thermo-fluid phenomena of room air were studied inside a few offices under cooling operation in stable room temperature conditions. Active Chilled Beams were found performing effectively in cooling mode operation. Surface temperature distribution and the air temperature distribution in the occupied zone were found uniform at all heights and close to the room setpoint. The air velocities were within the recommended air velocity set by ASHRAE Standard for thermal comfort except at the colliding jet between two beams in some offices. The operative temperature measured near the occupant was found close to the room setpoint. The supply air velocity and supply air temperature at both the slots of the beam were found different. It was concluded that the difference in supply air velocity could be due to the uneven pressure distribution in the primary air plenum owing to the connection method of the duct to the primary plenum and the difference in temperature could be due to the circuit arrangement of heat exchanger inside the Active Chilled Beam, which needs further research and investigation of the beam characteristics in a controlled environment.
Evaluation of thermal comfort and heat stress indices in different countries and regions – A Review
Authors: Yasmeen Sadia , Liu Hong
Published: October 2019

Energy efficiency, sustainability, productivity, thermal comfort, occupational health issues are emanating from rising global temperature associated with climate change. The prime purpose of this review is to focus on the present models to evaluate thermal comfort and heat stress level in various parts of the world in order to, identify the significant limitations in the development appropriate model. To assessed thermal comfort and heat stress a considerable number of models are already existing where about 40 models exist for only to determine heat stress itself. Existing comfort models are criticized for less metabolic rate, cloth insulation, not suitable for the outdoor diverse climate or for over or underestimation of the thermal concessions. On the other hand, to assessed heat stress WBGT-index is most widely used because of its simplicity. Several studies raised its limitations, whereas the PHS model is more appropriate but hard to understand for general people. For Thai people, HSI (Heat Stress Index) is best rather than others claimed by the authors. Thermal Work Limit (TWL) is suitable for both indoor and outdoor environments. Authors adopt the approaches to determine the region-based comfort and stress level through exploiting different models. For better evaluation models were improved through including or excluding new variables since the first development of thermal comfort indices. However, no unique model has developed afterward. Perfection and utilities of models depend on regional climatic behavior, which is apart from other relevant aspects. Therefore, further study should be necessary to establish a unique model or if not reasonable then focus on to obtain the accurate model for each climatic region.
Application of data mining in understanding the charging patterns of the hot water tank in a residential building: a case study
Authors: Mirnaghi M , Panchabikesan K , Haghighat F
Published: October 2019

Today’s buildings are adequately informative because of the wide implementation of the building automation system (BAS). In this regard, data mining (DM) tools have an excellent ability to interpret and discover interesting, unknown information from raw data collected from BAS. The present work is a case study, in which DM tools (such as clustering and decision tree) are applied to understand the operational pattern of a hot water storage tank (sanicube) used in a residential building, located in Scotland. The main objective of this study is to explore the correlation among the important features (storage tank temperature, solar collector, the operation of the sanicube heating element, etc.) in the chosen building. Interesting correlations and patterns between the solar collector, storage tank, sanicube-heating element are explored. The clustering results show the existence of different charging patterns of the storage tank and it highly influences the space heating (SH) and domestic hot water (DHW) temperature. The main inference from the result is that the charging of the storage tank is not automatic, and it is influenced by the occupancy behaviour. To maintain the temperature of the storage tank and subsequently to meet the SH and DHW demand, the operation of both solar collector and sanicube heating element (during night time) is recommended rather than operating only the solar collector.
Energy performance of building-integrated electrochromic and photovoltaic systems
Authors: Cannavale Alessandro , Martellotta Francesco , Ayr Ubaldo
Published: October 2019

Innovative nanotechnology-based devices can offer multiple advantages in terms of renewable energy harvesting as well as energy saving in buildings. Among the technologies that can be used in transparent and semi-transparent building envelopes, neutral-colored perovskite-based heterojunction photovoltaic (PV) cells and solid-state electrochromic (EC) devices may play a pivotal role. These classes of devices have proven to offer significant benefits in terms of energy saving and enhancement of indoor visual comfort. In this work, the two types of technologies will be compared by considering two similar buildings equipped with glazing embodying such devices, with reference to specific climate conditions.
Numerical study of residential Smart Dual Fuel Switching System (SDFSS) with on-site solar photovoltaic system
Authors: Shukla Saunak , Tung King , Yu Danilo , Fung Alan S
Published: October 2019

Building energy consumption accounts for approximately 36% of total energy consumption in the world. Since buildings are capable of on-site electricity generation and exhibiting predictive pattern of heating and cooling, the focus of this study is to investigate the Smart Dual Fuel Switching System (SDFSS), comprising a natural gas furnace and an air-source heat pump (ASHP), working in conjunction with on-site solar photovoltaic system. Base-case scenario using 1.5-ton rated capacity ASHP with 8.5 heating seasonal performance factor (HSPF) yielded only 4% cost savings and 15% greenhouse gas (GHG) emission reduction when compared to natural gas furnace space heating scenario. With an ASHP of 2-ton rated capacity and HSPF of 10 working in conjunction with solar photovoltaic (PV) system of 4.08 kWp, the cost savings of SDFSS increased to 12% and the GHG emissions reduction of 45%. SDFSS integrated with the grid is expected to yield significant benefits. It can help avoid situation of buildings drawing electricity all at once and reduce the overload on the grid. Also, it can redirect electricity generated from the solar PV system of a building for which using natural gas furnace is more economical to a building whose space heating demands can be met with this excess electricity. Higher ASHP performance and capacity, higher carbon pricing, and higher solar PV electricity generation will lead to the design of a more economical and sustainable SDFSS.
From awareness to energy saving: using user engagement to change occupants’ behaviour
Authors: Ayr Ubaldo , Guarini Davide , Martellotta Francesco , Porcelli Daniela , Sacchetti Antonio , Siliberti Massimiliano , Sulpasso Leonardo
Published: October 2019

Scientific literature in the last years provided clear evidences of the determining role occupants play in achieving the highest standards in energy saving and how bad management of HVAC systems, hot water, openings, and electric equipment, may result in increased consumptions, energy waste, and lack of comfort. Based on such assumptions, a campaign to promote occupants’ awareness about energetic implications of many daily actions has been launched at the beginning of 2018, by means of a smartphone app. Meanwhile, a selection of the most active users has been given a control unit capable of monitoring occupants’ movements, electric energy consumptions, indoor temperature and relative humidity, illuminance and carbon dioxide concentration. Such parameters can be accessed by means of another app, allowing the users to immediately see the effect of their actions in terms of energy savings and indoor environment quality. In addition, it is possible to monitor occupants’ habits, set (and send) specific alerts, and verify whether the suggestions given by the app actually induced relevant changes in users’ behaviour. The paper presents and discusses a preliminary set of the collected data and provides evidences of the positive feedback induced by the combined use of both apps and the control unit.
District heating thermal plant fed by biomass residues in a rural area of Central Italy
Authors: Manni M , Petrozzi A , Nicolini A , Cotana F
Published: October 2019

According to the European goals defined in EU Dir. 28/2009, biomass represents a valid alternative to fossil fuels. Combined heat and power (CHP) biomass plants are considered as advantageous in those rural areas which show critical issues regarding the disposal of organic wastes from agriculture and forestry activities. Furthermore, the connection of those villages to the national energy grid requires high operational costs which can be avoided by realizing an autonomous district system exploiting available renewable sources. The hereby study aims at demonstrating all these benefits through the presentation of a pilot project about a district heating system powered by a CHP biomass plant. The intervention has been proposed for a group of buildings located in Perugia, Central Italy. Their connection to the plant would be realized through an underground pipeline. Both the biomass exploitation and the district scale guarantee significant economic and environmental advantages. Indeed, the installing costs can be paid back in less than ten years considering (i) the savings from avoided natural gas exploitation and (ii) incomes from the disposal of wooden organic wastes.
Design and testing of I-ZEB, a zero energy laboratory for the integrated evaluation of the performance of building components and HVAC systems
Authors: Ludovico Danza , Lorenzo Belussi , Matteo Ghellere , Francesco Salamone , Chiara Scrosati , Fabio Scamoni , Alice Bellazzi , Anna Devitofrancesco , Benedetta Barozzi , Italo Meroni , Claudio Maffè , Michele Depalma
Published: October 2019

The scientific community, along with the worldwide governments, debate about the performances of buildings for decades and today the subject is still of topical interest. The recent regulatory framework requires increasingly high energy-efficient buildings in order to reduce the overall impact of building sector and to improve the user’s well-being. Several stakeholders are called upon to contribute to this end. The collaboration between the professional, industrial and scientific sectors is an engine of this challenge. Following this path, the Construction Technologies Institute (ITC) of the National Research Council of Italy (CNR) has recently developed a zero energy laboratory with the aim of creating the best platform where companies of the building sector and research bodies can share their expertise for the development and the test of products and systems to reach the Zero Energy Building (ZEB) standard. The paper focuses on the design and testing phases of the laboratory. High performance envelope, efficient HVAC and renewable energy systems are the technical pillars of the laboratory. Several characterization tests have been carried out in order to choose the most suitable technical solutions. The integrated solutions (products and systems) are tested through a continuous monitoring: energy and the Indoor Environment Quality (IEQ) variables measurements are performed.
Towards an ontology for holistic building occupant information modelling
Authors: Salimi S , Nik-Bakht M , Hammad A
Published: October 2019

Occupant behaviour (OB) is a critical factor affecting the building performance from aspects such as energy/comfort management, emergency planning, space management, and safety/security. Several ontologies were previously developed to formalize modelling/exchanging occupant-related information for each of these applications. The present study aims to provide a holistic occupant ontology to support integrated building management solutions. Rather than offering a brand new ontology, we integrate the existing models, and create the linkages required for semantic integration among them. Two main dimensions framing our occupant ontology include: building function and occupancy information. We mapped the available ontologies (within and outside the domain of OB), to capture existing gaps for semantic integration across multiple use-cases, within each of these dimensions. The gaps were then translated into competency questions, and from there, we developed meta-classes and relations required for the high-level occupant ontology. Upon the completion and deployment, the proposed occupant ontology can result in better information exchange and integration with building simulation models for various use-cases.
Techno-economic feasibility of Sewage Wastewater Heat Recovery (WWHR) based Community Energy Network (CEN) in a cold climate - a case study of Ryerson University, Toronto, Canada
Authors: Kwiatek Conrad , Sohail Usama , Fung Alan S , Joksimovic Darko
Published: October 2019

Wastewater is an underutilized and readily available source of carbon free thermal energy. The energy derived from wastewater can be augmented using heat pumps to supply thermal energy to buildings. Due to favorable temperatures, wastewater sourced heat pumps are able to operate more efficiently than air and ground sourced heat pumps. This paper evaluates the potential of using wastewater heat recovery (WWHR) to provide heating and cooling to a mid-sized university campus located in the urban center of Toronto, Canada.
Sustainable design for zero carbon architecture
Authors: Al-Temmamy M Z , Abd-Rabo L M
Published: October 2019

The energy is used for construction, operation and demolition in the building sector is the most significant source of carbon dioxide (CO2) emissions which is predicted to affect the environment. Therefore, under the Paris Convention, this paper explores the current situations and the way forward for achieving zero carbon building (ZCB). Firstly, ZCB’s are expected to decrease energy requirement via effective ‘passive and active design solutions ‘, then secondly by means of renewable energy supply systems to meet remaining energy demand. The focus would be on the ‘building envelope ‘that involves the shape, orientation, and building elements which usually remain unchanged throughout their life cycle. Naturally, the HVAC system and any building-integrated energy supply are going to be an integral part of the design. All of these are going to significantly reduce the demand for energy and CO2 emissions, which are an optimized solution for a comfortable and healthy environment.

In order to move forward, this paper encourages that ZCB principles should be explicitly determined within the need for computational modelling of buildings and their energy performance throughout the life-cycle of the building. Also, technical solutions may vary, but can be clarified around passive solutions and energy efficiency, on- and off-site renewable energy technologies, and carbon offsetting measures as these are explained in the case study.
The research on the influence of building air tightness to energy consumption of residential building in a hot summer and cold winter zone in China
Authors: Liu Yuan , Li Baizhan , Cao Xinyun
Published: October 2019

The hot summer and cold winter zone in China belong to the non-central heating area. In recent years, with the improvement of people’s living standards, more and more residential building have begun to adopt various heating methods. However, many existing buildings have poor air tightness level, and the indoor thermal environment is in a bad condition, which also causes a great waste of energy. Based on the actual measurement of the airtightness of a demonstration building, this paper studies the effects of residential airtightness on heating and air conditioning energy consumption and indoor thermal environment in winter. The simulation results show that in the hot summer and cold winter zone, the level of air tightness also influence the heating and air conditioning energy consumption, but the impact on heating energy consumption is more obvious. In addition, when selecting energy-saving measures, the relationship between the level of air tightness and the level of insulation should be weighed. We should not reduce energy consumption only by improving the airtightness level. Otherwise, the investment is large and the energy saving effect is very poor.
Life-cycle cost and environmental assessment of nearly zero-energy buildings (NZEBs) in four European countries
Authors: Mørck Ove , Gutierrez Miriam Sanchez Mayoral , Thomsen Kirsten Engelund , Wittchen Kim B.
Published: October 2019

Nearly zero energy buildings (NZEBs) are required as the minimum standard for all new buildings in Europe by January 2021. These buildings should, according to the Energy Performance of Buildings Directive (EPBD) [1], be cost optimal, i.e. the cost of constructing and operating the building over its lifetime should be at its minimum. The EU Horizon 2020 research project CoNZEBs, identify and assess technology solution sets that lead to significant cost reductions of new NZEBs in four EU member states. The project initially identified baseline costs for minimum energy performance buildings, NZEB and beyond NZEB in the four countries and then a number of solution sets with lower investment costs than those of typical NZEBs. The next step was to carry out life cycle cost and environmental assessment analyses on the identified solution sets and compare these to minimum energy performance, typical NZEB and beyond NZEB buildings. The results of this work for one of the countries – Denmark – is presented below as an example.
Impact of temperature and moisture dependent conductivity of building insulation materials on estimating heating and cooling load using typical and historical weather data
Authors: Siu C Y , Wang Y Y , Liao Z
Published: October 2019

This paper investigates the impact on heating and cooling load estimation when effective thermal conductivity of materials is incorporated into building energy simulation in conjunction with historical weather data. Under current practice, thermal performance of building envelope systems is usually represented by a lumped nominal conductivity value. In reality, effective conductivity is influenced by many factors such as temperature and moisture content. To minimize computing time, building energy simulation is also conducted with typical meteorological weather data, which is sufficient in estimating average energy use of buildings, but lacks the ability to truly reflect building performance under long term weather conditions. Preliminary research has been conducted by simulating a typical residential house in Toronto using WUFI plus - a comprehensive hygrothermal building simulation program. Historical CWEED - 1998 to 2014 weather data and typical weather files CWEC-1990s and 2016 have been used for this work. The results shows:1)a reduced representativeness of typical weather data in building energy simulation as climate changes over time; 2)estimation using typical weather data is not representative of any individual historical year and 3)performance of insulation materials changes when temperature and moisture dependant conductivity is considered and affects the results of building energy simulation.
A nearly Zero Energy Building in Mediterranean climate: a case study in Mesagne (Apulia)
Authors: Stasi R , Paterno S , Stragapede A , Liuzzi S , Stefanizzi P
Published: October 2019

This paper presents the case study of an nZEB building located in the municipality of Mesagne (Apulia, BR). It is a building of 309 m2 of usable floor space with two floors above ground. The building is a proof that a correct integrated design of the HVAC system and the building envelope can easily lead to an nZEB building with high performance in terms of energy consumption and comfort. The external envelope of the building is a structure in tufa blocks plus a mixture of hemp and hydraulic lime plus blocks of hemp and lime. Hemp lime is a mix of renewably sourced hemp shiv, a specially formulated lime binder and water. The air conditioning system is based on a controlled mechanical ventilation with air pre-treatment through an underground tube exchanger. A numerical simulation of the overall building-plant system performance was made with DesignBuilder in order to evaluate the energy consumption for air conditioning and the thermohygrometric comfort in the building. Several simulations were carried out to compare the incidence of different building-plant system on total energy consumptions: one without earth-to-air heat exchanger, one without heat-recovery and recirculation, one without solar shading.
Technoeconomic assessment of solar combined heat and power systems based on hybrid PVT collectors in greenhouse applications
Authors: Wang Kai , Pantaleo Antonio Marco , Mugnozza Giacomo Scarascia , Markides Christos N.
Published: October 2019

This paper presents a technoeconomic analysis of a solar combined heat and power (S-CHP) system based on hybrid photovoltaic-thermal (PVT) collectors for distributed cogeneration in a greenhouse tomato-farm in Bari, Italy. The thermal and electrical demands of the greenhouse of interest are currently fulfilled by a gas-fired CHP system that features an internal combustion engine (ICE) prime mover, and partially by an auxiliary gas boiler and electricity from the grid. A PVT-water S-CHP system is designed and sized based on a transient model, with hourly weather data and measured demand data given as inputs. Annual simulations are performed to predict the transient behaviour of the S-CHP system and to assess the system’s energy outputs. The economic profitability of such solution is also evaluated by considering the investment costs and cost savings due to the reduced on-site energy consumption. The results show that, with an installation area of 30,000 m2, the PVT S-CHP system is able to cover up to 73% of the annual thermal demand of the greenhouse, while delivering a net electrical output 2.6 times that of the annual electrical demand. This performance is similar to that achieved by the equivalent ICE-CHP system (92% and 2 times, respectively). Furthermore, the total annual cost saving of the PVT S-CHP system is more than 6 times higher than that of the ICE system, due to the much lower fuel cost of the PVT system. Similarly, the potential CO2 emission reduction associated with the PVT system is considerably higher, at 3010 tCO2/year saved (vs. 86 tCO2/year). The payback time of the PVT system is not significantly longer than that of the ICE system (10.4 years vs. 8.4 years), but its levelized cost of energy is much lower (0.076 €/kWh vs. 0.132 €/kWh) due to the higher annual cost savings. These results indicate that such PVT S-CHP systems have an excellent technoeconomic potential in the proposed greenhouse applications and could be competitive over conventional fossil-fuel-based ICE-CHP systems in terms of energetic, economic and also environmental metrics.
Study on building performance considering climate characteristics for university facility in Japan
Authors: Naito Yuki , Kuwahara Ryoichi
Published: October 2019

This study was investigated the building performance of each area for university facilities. The purpose is to propose optimal building performance for each area. As the background, the target building needs the energy-saving renovation. The target building has been built for 25 years and aged. In addition, the primary energy consumption of the target building is larger than the primary energy consumption of standard university facilities. Therefore, it is necessary to renovate buildings and facilities, and plans should be made to save more energy. This research method was examined changing the building performance for each area by using the Building Energy Simulation Tool (BEST) program of the energy simulation. Building performance is the thermal insulation of the outer wall and the type of glazing. As a result, In Ube, primary energy consumption tends to increase if thermal insulation performance is increased too much. In Sapporo, primary energy consumption tends to decrease as thermal insulation performance increases. In Naha, it turned out that increasing the thermal insulation performance is not effective.
Towards a universal ranking system for design parameters’ impact on buildings’ lifecycle energy
Authors: Panizza Rafaela O , Nik-Bakht Mazdak
Published: October 2019

The energy consumption of buildings depends on numerous factors that can be categorized in four major categories: geometry parameters; location; attributes of electric and mechanical systems; and behaviour of users. Most of the existing publications on ‘energy-consumption influencing parameters’ test the sensitivity of energy consumption to these inputs in a single building; not making it possible to correlate different projects. The purpose of this study is to evaluate the impact caused by the model when evaluating parameters. In this paper we have studied a series of nine real-world design projects in cold climate (Québec, Canada) to analyse the behaviour of thirteen design parameters. Among the four major categories mentioned above, our scope is limited to geometry parameters (variation in climate, mechanical systems and occupants is excluded). The parameters include building orientation; window-to-wall ratio; overhang size; insulation; and Solar Heat Gain Coefficient (SHGC) for windows. All parameters are analysed using the Morris method for sensitivity analysis and are ranked based on the simulation results. According to the results, window-to-wall ratio and orientation show lower variation among different models while insulation, overhangs and SHGC appear to be more sensitive. The developed analysis is the starting point to what can be a shortcut for designers to control energy consumptions efficiently in new designs.
Building performance monitoring: from in-situ measurement to regression-based approaches
Authors: Tronchin Lamberto , Manfren Massimiliano , Vodola Vincenzo , Nastasi Benedetto
Published: October 2019

Simple and robust data analysis methodologies are crucial to learn insights from measured data and reduce the performance gap in building stock. For this reason, continuous performance monitoring should become a more diffuse practice in order to improve our design and operation strategies for the future. The research presented aims to highlight potential links between experimental approaches for test-facilities and methods and tools used for continuous performance monitoring, at the state of the art. In particular, we explore the relation between ISO 9869:2014 method for in-situ measurement of thermal transmittance (U) and regression-based monitoring approaches, such as co-heating test and energy signature, for heat load coefficient (HLC) and solar aperture (gA) estimation. In particular, we highlight the robustness and scalability of these monitoring techniques, considering relevant issues in current integrated engineer design perspective. These issues include, among others, the necessity of limiting the number of a sensors to be installed in buildings, the possibility of employing both experimental and real operation data and, finally, the possibility to automate and perform monitoring at multiple scales, from single components, to individual buildings, to building stock and cities.
Influence of LCA procedure on the green building rating tools outcomes
Authors: Mattoni Benedetta , Bisegna Fabio , Evangelisti Luca , Guattari Claudia , Asdrubali Francesco
Published: October 2019

Building energy performance has a key role in the international energy scenario. Labelling procedures have been developed in several countries for certifying the environmental sustainability of buildings, aiming at reducing energy consumptions and environmental impacts.

In this study, the impacts of the insulating materials on the energy and environmental performance of a residential building have been analysed. From previous studies developed by the same authors, it emerged that the sustainability protocols LEED and ITACA take into account the thermal properties of the insulating materials but their impact on the environment is not adequately considered. Starting from these considerations, in this work a life cycle analysis was carried out on the four insulating materials in order to highlight if and to what extent they differ in terms of environmental impacts. What emerged from the results is that the balance between nature, origin and amount of input materials strongly influences the results and the natural materials are not always the most sustainable and eco-compatible.
Towards resilient cities: Advancements allowed by a multi-criteria optimization tool to face the new challenges of European Union’s climate and energy goals
Authors: Buggin Antonio , Gennusa Maria La , Peri Giorgia , Rizzo Gianfranco , Scaccianoce Gianluca , Scarpa Massimiliano , Schibuola Luigi , Tambani Chiara
Published: October 2019

The United Nations as well as the European Union are strongly committed in promoting a transition towards more sustainable and resilient cities. Indeed, they are increasingly affected by different types of threats, among which the natural ones such as earthquakes, fires, and floods (shocks) and climate variability (stresses). Cities are quite often unable to cope with the adverse effects of such natural hazards. This circumstance leads to the need of introducing resilience-related criteria (besides commonly used sustainability indicators) in decision-making processes. This paper investigates at which extent the inclusion of such new indicators, within multi-criteria assessment tools for supporting the decision-making process by Public Administrations, modifies the prioritization processes of a given set of planned actions to be implemented in cities, which are based instead on the above-cited commonly used indicators. The outcomes of the analysis demonstrated that the introduction of resilience among the prioritization criteria significantly modifies the list of priorities established using only sustainability indicators.