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Highlights • The aim of this research is to investigate the thermal performance of the prototype building to assess overheating in the summer, particularly the long-term heatwave period in the UK. • To understand the impact of energy efficient technologies on occupants' wellbeing and health in order to identify occupants' thermal comfort level in these types of dwellings. • The study adopts a quantitative research design based on indoor monitoring, in-situ measurements and dynamic simulation modelling. • This clearly indicates that due to this prototype house's structural construction material behaviour in a heatwave and its location (southwest facing orientation), it is susceptible to very high overheating risk. • The results found from the monitoring during a long-term heatwave in the summer of 2018 provided strong evidence for overheating and thereby thermal discomfort in many occupied spaces, particularly on the first floor followed by several spaces on the ground floor. Meanwhile, all the occupied spaces appeared to be well above the acceptable thermal comfort benchmark throughout the data collection period. • To calibrate the building performance, as well as the building materials and components adopted in the model, the measured indoor environment data were scrutinised in conjunction with the IES simulation results. Abstract There is growing evidence that terraced houses—thermally lightweight, well insulated, naturally ventilated with three exposed wall surfaces—are at risk of overheating, especially in south-eastern England. The aim of this study is to evaluate the building performance and develop a reliable building simulation, which will be employed in the second phase of the study: developing affordable and feasible passive design strategies to support the energy-efficient building systems of the construction industry. This paper reports on the results from the first phase of the study where a quantitative methodology, including indoor and outdoor environmental monitoring, in-situ measurements and building simulation modelling, was adopted. The performance of a case study was modelled and simulated via employing Integrated Environmental Solutions (IES) software suite. The results from the base-case were analysed according to the adaptive thermal comfort of Chartered Institution of Building Services Engineers (CIBSE) Technical Memorandum 52 guidelines: The Limits of Thermal Comfort—Avoiding Overheating in European Buildings. The spaces studied within the case study house were observed to exceed the acceptable limits of thermal comfort; particularly, the large bedroom within this zone exceeded the upper limit for overheating up to 11 h daily. Furthermore, the results from the monitoring study indicate a high risk of summertime overheating across all the case study settings, especially during short-term peaks in outdoor temperatures. The main reasons for the problematic thermal performance were identified as well-insulated and fully air-tight building fabric, the lack of sufficient ventilation through the living spaces and excessive heat gains through the composite cladding material. [ABSTRACT FROM AUTHOR]

This paper analyses annual energy performance of atrium type hotel building in Belgrade. The objective is to examine the impact of the atrium on the hotel building’s energy demands for space heating and cooling. Integrated approach through numerical simulations that include Belgrade climate data and thermal comfort parameters, indicates an optimal model of hotel building with atrium for this area. Building energy simulation is carried out using EnergyPlus simulation engine, as a basic tool in the process of building energy optimization. The methodological approach includes the creation of a hypothetical model of an atrium type hotel building, numerical simulation of energy performances of several design alternatives of the hotel building with atrium, and comparative analysis of the obtained results. The main task of analysis is to change certain parameters in the particular model (for example, building structure, orientation, etc.) and to observe how the changes influence energy performance of the building. The goal of this research is to show that the atrium contributes to the heating and cooling energy savings in the rest of the building, but also that the atrium itself demands a lot of energy for its air-conditioning. The most sustainable solution should be to cover energy demands for atrium by using the renewable energy sources. In this case, the atrium can contribute to the energy efficiency of the hotel building in Belgrade climatic conditions, thus reducing its negative impact on the environment. [ABSTRACT FROM AUTHOR]

Despite the acknowledged positive effects of vegetation at urban, neighborhood and building scales, there are still only limited comprehensive design tools for multi-scale evaluation of the microclimate and thermal benefits of plants and building-integrated vegetation (BIV) systems. The paper describes a case study in the city of Palermo (Italy) that applied simulation methodology to quantitatively assess the microclimate effects of different neighborhood and building retrofit scenarios where vegetation plays a main role. The simulation workflow moves from a micro-urban to a building scale assessment by linking the ENVI-met software to the building energy simulation program EnergyPlus. The study takes two complementary directions. Firstly, it analyses the influence of plants on urban microclimates to enhance outdoor and indoor temperatures. Secondly, it assesses the benefits of different technical solutions applied to buildings, including BIV systems and windows substitutions, to further improve their thermal behavior. The results of the simulations show a significant reduction in outdoor and indoor temperatures, questioning traditional urban renovation practices and drawing attention to the importance of multi and inter-scale approaches for high-accuracy investigations into buildings’ thermal performances. [ABSTRACT FROM AUTHOR]

Diffuse ceiling ventilation (DCV) is a novel air distribution system that utilizes the suspended ceiling as diffuser for inlet air. The performance and system characteristics have, so far, mainly been tested in laboratory experiments and numerical simulations yielding good results in terms of occupant comfort at high ventilation rates. To supplement these results and study the performance under realistic conditions, a classroom retrofitted with a mechanical exhaust-driven DCV system has been investigated and reported in this paper. The performance was evaluated in terms of air movements and preheating capabilities in the plenum, as well as ventilation effectiveness and thermal comfort in the occupied zone. No evidence for the presence of a fully sustained pressure chamber effect was found though; instead, measurements indicate that the supplied air characteristics changed as function of distance from the plenum inlet, due to cross-contamination with room air and too low pressure resistance in the suspended ceiling. The DCV system performed satisfactory, though, both during quasi-steady-state and under transient conditions, sustaining a fully mixed occupied zone without any risk of draught or discomfort due to vertical temperature gradients. Ventilation effectiveness was comparable to conventional mixing ventilation with indications of displacement effects. [ABSTRACT FROM AUTHOR]

It is known that building performance usually involves different criteria such as the energy consumption, thermal comfort, thermal loads and internal temperatures, which can make its assessment more complex. Thus, this paper aims to describe a decision-making process to improve some criteria related to the energy efficiency of residential buildings considering a multicriteria approach. Computer simulation using EnergyPlus v8.3-2014 was performed to assess the thermal and energy performance of a residential building for four different climates in Brazil (Belém, Campo Grande, Curitiba and Florianópolis). The performance criteria were the degree-hours and energy consumption for air-conditioning (both for heating and cooling) in different decision makers’ preference scenarios. The performances of eight constructive systems were evaluated considering uncertainties related to the operational variables of the building, obtained through field survey. The results showed that some systems had statistically equivalent performance considering the range of uncertainty. The system of masonry with double massive brickwork performed better for three climates; for Belém, however, an adequate system highly depends on the preference scenario. Nonetheless, different preference scenarios would indicate different adequate systems for all climates. This study used a method of decision-making which enables the possibility for future analyses of other performance alternatives, design variables, and performance criteria. [ABSTRACT FROM AUTHOR]

Variable refrigerant flow (VRF) systems vary the refrigerant flow to meet the dynamic zone thermal loads, leading to more efficient operations than other system types. This paper introduces a new model that simulates the energy performance of VRF systems in the heat pump (HP) operation mode. Compared with the current VRF-HP models implemented in EnergyPlus, the new VRF system model has more component models based on physics and thus has significant innovations in: (1) enabling advanced controls, including variable evaporating and condensing temperatures in the indoor and outdoor units, and variable fan speeds based on the temperature and zone load in the indoor units, (2) adding a detailed refrigerant pipe heat loss calculation using refrigerant flow rate, operational conditions, pipe length, and pipe insulation materials, (3) improving accuracy of simulation especially in partial load conditions, and (4) improving the usability of the model by significantly reducing the number of user input performance curves. The VRF-HP model is implemented in EnergyPlus and validated with measured data from field tests. Results show that the new VRF-HP model provides more accurate estimate of the VRF-HP system performance, which is key to determining code compliance credits as well as utilities incentive for VRF technologies. [ABSTRACT FROM AUTHOR]

Occupant behavior is a major contributing factor to building energy consumption. Large discrepancies might occur when occupants with diverse types in terms of behavior patterns reside in an identical building. Moreover, it is vital to derive several kinds of typical occupant behavior that represent the assemblage of occupants in a simplified way as the reference for building designers and energy policy makers. This paper presents a preliminary research on occupant behavior categorization through the building energy simulation, where some typical occupant air-conditioning behavior patterns use in Chengdu, China have been derived from a large-scale questionnaire survey based on the energy consumption levels. These typical occupant behavior patterns could be used as the context for an overview of building energy in a community, as well as the evaluation of building energy-saving technology where occupants are involved. Further efforts are required in the algorithm of dividing occupant behavior into typical patterns, the validation of the classification results, and the analysis of other behaviors. [ABSTRACT FROM AUTHOR]

Traditionally, in building energy modeling (BEM) programs, occupant behavior (OB) inputs are deterministic and less indicative of real world scenarios, contributing to discrepancies between simulated and actual energy use in buildings. This paper presents a new OB modeling tool, with an occupant behavior functional mock-up unit (obFMU) that enables co-simulation with BEM programs implementing functional mock-up interface (FMI). The components detailed in the development of the obFMU include an overview of the DNAS (drivers-needs-actions-systems) ontology and the occupant behavior eXtensible Markup Language (obXML) schema, in addition to details on the creation of the obFMU that contains the co-simulation interface, the data model and solvers. To demonstrate functionality of the tool, three examples of occupant behaviors were simulated, including: (1) turning on and off lights, (2) opening and closing windows, and (3) turning on and off the air conditioners. The obFMU can be used via co-simulation with all building simulation programs that implement the FMI, thus users are not limited to a particular tool. Another advantage is the use of obXML schema to represent occupant behavior, standardize the description of occupant behavior enabling information exchange. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) has been studied in the building science realm for about three decades. However, the following two aspects of the building control have not been studied thoroughly in MPC research. One is the impact of the mixed-mode cooling system on the active heating ventilation and air conditioning (HVAC) energy consumption, and the other is the differences of individual thermal comfort preference and its impact on energy. This paper proposes an occupant-oriented mixed-mode EnergyPlus predictive control system to optimize HVAC energy consumption while meeting the individual thermal comfort preference. A web-based dashboard is implemented in the test-bed building for three months to collect individual thermal comfort preference data. The data analysis results suggest that occupants have various tolerances and preferences about thermal comfort. The simulation results show that, during one week of a typical swing season, the mixed-mode system further reduces the active HVAC energy consumption, and the diversified occupant thermal comfort preference has significant impact on HVAC energy consumption. [ABSTRACT FROM AUTHOR]

This paper introduces a Human and Building Interaction Toolkit (HABIT) for simulating the thermally adaptive behaviors and comfort of office occupants alongside building energy consumption. The toolkit uses the Building Controls Virtual Test Bed (BCVTB) to co-simulate a field-tested, agent-based behavior model with an EnergyPlus medium office model. The usefulness of the toolkit is demonstrated through a series of zone and building-level case study simulations that examine the wisdom of pairing local heating and cooling options with strategic thermostat set point offsets, judging from the energy, Indoor Environmental Quality (IEQ), and cost perspectives. Results generally suggest that trading efficient local heating/cooling options for whole space conditioning has both energy and comfort benefits, saving up to 28% of monthly HVAC energy while improving the acceptability of thermal conditions in a Philadelphia climate. Nevertheless, cost analysis shows that the fuel source of conserved energy must be considered – particularly in the case of personal heater use, which adds to electric plug loads and associated utility and CO 2 emissions cost penalties. Moreover, costs from even small changes in simulated occupant productivity tend to overwhelm energy costs, suggesting the need to improve the accuracy and precision of available productivity models across multiple seasons and climates. [ABSTRACT FROM AUTHOR]

In tropical countries such as India, increasing the roof albedo helps to reduce the heat ingress through the roof. This further reduces air-conditioning energy consumption in conditioned buildings and increases comfort in unconditioned buildings. In order to help users determine the benefits of high albedo roofs under varying conditions, a simple calculator has been developed. Parameters such as location, building type, roof area, and surface properties of the roof are taken as inputs. Annual EnergyPlus simulations are performed for the given parameters and the results are displayed in both graphical and tabular formats. It also calculates the simple payback by comparing a given base case roof albedo with the proposed roof albedo. The calculator can perform comfort simulations for unconditioned buildings and simulates measures including a radiant barrier system and under deck roof insulation. The calculator also runs a parametric simulation between insulation thickness and roof albedo to find an optimum roof insulation thickness based on incremental internal rate of return. This paper presents the features of the cool roof calculator and the type of analysis that can be performed using the cached results. [ABSTRACT FROM AUTHOR]

The subject of this paper is the residential buildings’ thermal performance and comfort in the city of São Paulo, taking into account the climate changes and the greater vulnerability of the elderly related to the environmental conditions. The aim is the evaluation of thermal performance and comfort in residential buildings under the RCP 8.5 scenario from the IPCC Fifth Assessment Report, as well as under the heat wave occurred in January and February 2014. This study is based on real case studies and computer simulations carried out using EDSL TAS. Three elderly dwellings were surveyed and monitored aiming the comparison between measurements and computer simulation to calibrate the models. For the computer simulations, simulated and measured climate data were employed. Results were analyzed comparing comfort conditions in the different climate scenarios and among the case studies, following two adaptive comfort indexes selected for this study. Analysis revealed a tendency of change in comfort conditions following the progression of the climate scenarios, showing an increase in heat sensation and a decrease in cold sensation. The results show that the combination of both phenomena, climate change and heat wave, may lead to a potential effect of heat discomfort. [ABSTRACT FROM AUTHOR]

Outdoor thermal comfort has been a widely concerned issue in tropical and subtropical cities. In order to assess the conditions of outdoor thermal comfort, quantitative information on different spatial and temporal scales is required. This paper employs a numerical model (SOLWEIG – SOlar and LongWave Environmental Irradiance Geometry) to examine the spatial and temporal variations of mean radiant temperature ( T mrt ), as an indicator of radiant heat load and outdoor heat stress in high-density sub-tropical urban environment in summer. The SOLWEIG model is found to simulate the six-directional shortwave and longwave radiation fluxes as well as T mrt very well. Simulation results show that urban geometry plays an important role in intra-urban differences in summer daytime T mrt . Open areas are generally warmer than surrounding narrow street canyons. Street canyons are sheltered from incoming direct solar radiation by shading of buildings while open areas are exposed to intense solar radiation, especially along the sunlit walls where high T mrt is observed due to reflected short-wave radiation and long-wave radiation emitted from the sunlit building walls. The present study confirms that there are great potential in using urban geometry to mitigate high radiant heat load and daytime heat stress in the compacted urban environment. In high-density subtropical cities where high daytime T mrt causes severe thermal discomfort in summer, dense urban structures are able to mitigate the extremely high T mrt and improve outdoor thermal comfort. However, the shading strategy has to be cautious about air ventilation in such a dense urban environment. [ABSTRACT FROM AUTHOR]

Technological advances in the field of energy conversion have led to the development of multi-carrier energy systems (MCESs). The ability of MCESs to manage different forms of energy can improve the efficiency and reliability of power systems. This paper attempts to address the dynamic behavior of loads in reliability evaluation of MCESs. A Markov-Chain Monte-Carlo approach is employed to model the dynamic behavior of thermal loads. The proposed model also investigates the mutual dependence between different forms of energy and its influence on availability of supply. Numerical simulations of an energy hub are provided to demonstrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]