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• Qualitative outcomes of energy poverty across Australian climate zones are compared. • Outcomes influenced by energy costs and local energy, housing and welfare policies. • Measures of energy poverty and policy responses need to reflect local contexts. Academic interests into energy poverty have been growing since the 1990s. These have ranged from quantitative measures and qualitative reflections, as well as ones that aimed to provide more nuanced definitions. These studies have, however, typically focused on single jurisdictions or across national borders, with very few examining the issue across different climatic and policy contexts within the same nation. This paper aims to address this gap by focussing on differences in climate conditions, local policies and quality of the housing stock across Australia and reflects on how these factors each played a role, to varying degrees, in the prevalence of energy poverty amongst lower-income households across eight metropolitan and regional settings conducted as part of a recent study in Australia. Through a review of focus group, interview and workshop data, it especially highlights the more qualitative impacts of energy poverty, and how each of these factors come to influence the extent to which lower-income households experience energy poverty and the support they were able to access. Additional to the need for more contextualised measures of energy poverty, this paper calls for localised responses to alleviate the negative outcomes reflected by our participants in regard to both energy and housing policies. [ABSTRACT FROM AUTHOR]

Recently there has been growing interest in regenerative evaporative coolers (REC), which can reduce the temperature of the supply air to below the wet-bulb of intake air and approach its dew-point. In this paper, we designed, fabricated and experimentally tested a counter-flow REC in laboratory. The REC’s core heat and mass exchanger was fabricated using stacked sheets composed of high wicking evaporation (wickability of available materials was measured) and waterproof aluminium materials. The developed REC system has a much higher cooling performance compared to conventional indirect evaporative cooler. However, the decision to use the REC for China buildings depends on a dedicated evaluation of the net energy saved against the capital expended. Such an evaluation requires the hourly-based data on the availability of cooling capacity provided by the REC for various climates. The paper used an experiment-based method to estimate the cooling capacity and energy savings provided by the proposed REC for China’s various climates. By using the experimental results and regional hourly-based weather data, the energy saving potential of the REC against an equivalent-sized mechanical air conditioner alone was analysed. The results indicate that, for all selected regions, the REC could reduce 53–100% of cooling load and 13–58% of electrical energy consumption annually. [ABSTRACT FROM AUTHOR]

The use of active thermal energy storage can provide energy savings, cost reduction and CO 2 mitigation by reducing energy demand for heating and cooling, allowing the use of peak load shifting strategies and enhancing the introduction of renewable energies in the sector. The high investment cost of these systems makes mandatory an appropriate control in order to maximize the energy benefits during its operation. Within this context artificial intelligence techniques have been successfully used to control active thermal energy storage units. This paper uses an experimentally validated numerical tool to study the effect of different control strategies on the performance of one TES system applied to the building sector, a ventilated facade with PCM which uses free cooling. Three different strategies were designed to control the ventilated facade based on cost savings, energy reduction and CO 2 mitigation, under different climatic conditions. Results show robust benefits in the three tested control strategies, achieving average savings in comparison to a manual operation of the system of 4.3%, 7.8%, and 16.7%. Moreover, the paper shows that when the control strategy is focused on optimizing cost, the other two benefits claimed by TES systems (energy and CO 2 mitigation) are significantly reduced. [ABSTRACT FROM AUTHOR]

Technology transfer, scientific research and education could have a key role in Mediterranean regions, in order to reduce the environmental impact of the building sector. Recently, the Department of Engineering of University of Sannio has developed a laboratory suitable for performing researches on the dynamic interactions between building envelope components, indoor environment and mechanical systems for a typical climate of south of Italy. The work described within this paper is a part of this large-scale project. Its goals are: (a) to design, test and validate a poly-equipped test room, (b) to perform transient tests to determine performances of common and innovative building components and alternative HVAC systems. More in detail, this paper focuses on the first goal, with the aim to generalize the design approach, requirements and capabilities of calibrated outdoor test facilities, specifically thought for Mediterranean climate. The facility has undergone a substantial amount of characterization tests, aimed at determining its response under yearly operations. The primary conclusions are that the new test facility is usable for a wide range of environmental and indoor conditions, it is functional and has been validated through characterization and preliminary investigations of the behavior of the thermal envelope. Moreover, some experimental results are here analyzed, by evidencing the potentialities of vacuum insulation panels for improving the performances of the thermal envelope, for what concerns both winter and summer seasons. Then, some numerical analyses have been carried out. A 3D CFD model has been calibrated for studying the real distribution of temperatures and water vapor partial pressures within VIP panels. Furthermore, a dynamic energy model of the test cell has been developed by means of Energy Plus, with the aim to use its capability to compare potential configurations that would be installed in future researches, or to evaluate energy, environmental and economic issues. [ABSTRACT FROM AUTHOR]

The acceleration of urbanization and the growth of population are considered to be the reasons of increasing demands for construction, life quality and energy consumption. This leads to more research in climate adaptive strategies such as traditional design methods, construction techniques and building materials. Traditional dwelling has been successful in achieving harmony between dwelling and climatic environment, which is one of the most important conditions for sustainability. Firstly, this paper focused on analyzing the characteristics of traditional dwellings in Qinba mountainous areas to adapt to the climatic environment. Secondly, two typical dwellings constructed respectively with brick and earth materials were selected for monitoring and simulating of its indoor thermal, luminous and ventilation environment in summer and winter. In addition, the research summarized the advantages and disadvantages of the dwelling's physical environment in response to climatic characteristics. It revealed that the traditional earth dwelling is well adapted to the local climate during summer, although the indoor thermal comfort is not fully satisfactory during winter. Finally, we prompted effective climate adaptive strategies of traditional earth dwelling, such as natural ventilation, thermal insulation and thermal buffer space. We want to provide guidance and reference for the development of traditional dwellings in the mountainous areas. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents the evaluation of the current HVAC components and indoor climate of a high tech Naval Depot when the system fails. The methodology of the research was: first, implementation of the heat, air & moisture models of the building and HVAC components. Second, validation of the models using measured data from the existing building control system. Third, simulation of the current and new HVAC systems designs. Fourth, discussion of the usability of the approach. For this specific case, we concluded that the current system design performs well if, in case of a fault, the air supply to the depots is switched off automatically. The construction of the depots has sufficient thermal inertia to maintain a stable indoor climate for a period long enough to allow it to be repaired. The design could be further improved by controlling the indoor climate surrounding the depots instead of inside the depots itself. In such a case, even if the system did not detect a fault and continued supplying uncontrolled air to the surroundings of the depot, the indoor climate in the depot would remain stable. We conclude that the approach presented in this paper has a wider application than this single case study. [ABSTRACT FROM AUTHOR]

In this paper, the thermal and ventilation performance of an ecological house in Helsinki, Finland are presented. The single-family dwelling has a well-insulated, wooden frame construction with no plastic vapour retarder. The measured and simulated results show that the energy consumption of the house is low and that the outdoor ventilation rate is generally satisfactory based on the measured CO2 concentrations. Extrapolating the measured ventilation data shows that, when the operable windows are closed, the ventilation rate is expected to be about 0.45 air-changes-per-hour (ach) in the winter and about 0.25 ach in the summer. The consumption of total primary energy and space heating energy were measured to be 30% less (162 kWh/(m2 a)) and 36% less (76 kWh/(m2 a)) than in typical Finnish houses, respectively. The paper also uses a numerical model to investigate the sensitivity of energy consumption to the insulation level, household electricity and domestic hot water consumption, window area, ventilation rate and heat recovery effectiveness. [Copyright &y& Elsevier]

Thermally activated building system (TABS) is a hydronic cooling system, in which cold water is circulated through pipes embedded in the building structure to remove the heat from the indoor space. This paper proposes a hybrid passive cooling system, in which TABS is integrated with a cooling tower. The performance of this integrated system greatly depends on the climatic conditions of the geographical area. Hence, the feasibility of the proposed system to provide thermal comfort in twelve Indian cities spread over five different climatic regions is investigated using COMSOL Multiphysics. Different cooling scenarios like Roof and Floor cooled TABS (RF) and All Surfaces cooled TABS (AS) are compared. The proposed system performs well in arid and semi-arid regions, and the RF scenario is sufficient to achieve thermal comfort. The system is able to reduce the indoor operative temperature by 14 °C for the arid climatic conditions of Jaipur. In the other three regions, i.e., humid subtropical, tropical wet and dry and tropical wet regions, the performance of the proposed system is relatively low and the AS scenario is required to achieve thermal comfort. [ABSTRACT FROM AUTHOR]

As of 2007 more than half of the world’s population is living in urban areas (a figure expected to rise to 60% by 2030). Thus, the liveability of the high-density city is gradually becoming a central point of focus and concern. A successful skyscraper model of urban planning could provide the possibility to increase city-space vertically as opposed to the current continuous expansion outward, which has obvious environmental consequences. However, skyscraper development, as well as all other new construction and gradually the older building stock, has to comply with current strict regulations on building energy efficiency. Contemporary high-rise examples do not present a sustainable solution to an increasing population or as models of prosperity, as they are linked to high-energy demand, environmental and social imbalances. This paper looks at design strategies towards promoting skyscraper energy efficiency by considering a climatically responsive design, where orientation, the thermal properties of the building envelope and the effect of altitude, become the main design tools. Initial simulations were performed for a residential and an office reference structure 100 m high. Different scenarios were implemented for gradually upgrading the building envelope and studying its relationship with the changing microclimate with altitude (wind speed increase and dry bulb temperature drop) between ground and top level. The advanced envelope was then simulated to up to 400 m high (120 stories high), and heating and cooling loads were compared in relation to different building heights and uses. EnergyPlus is used as the main simulation tool as it accounts for wind speed increase and dry bulb temperature drop with height. The location chosen is Tel Aviv, Israel, a city already growing upwards and expected to have a significant increase in skyscraper construction in the coming years. The results of the simulations performed present the base upon which further design strategies can be implemented towards reducing the environmental impact of this challenging building type. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of occupant lifestyle patterns on the energy performance of the residential buildings with various building envelopes in different climate zones. For this purpose, an existing multi-family apartment building in Iran was selected as the experimental residential building and the validity of energy simulation was examined based on the real data of the building energy consumption. The energy demand of the building before and after renovation was simulated via EnergyPlus for different climate zones. The sensitivity analyses confirmed that the occupants’ behavior has a significant impact on the building's thermal energy usage especially in hot climate areas and can change the heating and cooling loads up to about 90%. Using the validated model, a parametric study was performed to investigate the influences of the occupant's behavior on the efficiency of the building envelope including window and cladding materials in different climate zones. The results show that the interaction between the occupants’ behaviors and envelope materials is significant in that the occupant behaviors can change the strategy of choosing the envelop material types. Fluctuation of thermal energy consumption caused by changing of window types can rise to 20% for this case study. Also, it is shown that underestimating the level of occupancy loads can exaggerate the effects of the envelope on the thermal energy consumption rate. Overall, this study emphasizes the importance of applying near actual user behavior data on energy simulation analyses performed for the studies of building sustainability and lifecycle assessment. [ABSTRACT FROM AUTHOR]

The trend in urban population growth marks the sustainable development of cities as a critical challenge on the path towards the efficient use of resources and the mitigation of the environmental impact of human activity. Scientific studies have generally focused on the quantification of the environmental impact derived from the usage/operational stage of buildings. This study also includes the impact associated with the use of public facilities and services in cities. The aim of this paper is to study the CO 2 emissions from the use stage of buildings and public facilities through different urban planning solutions. Six development scenarios have been evaluated, considering the most common residential building typologies with a common construction surface, which includes: single- family units (detached and semi-detached) and apartment blocks of different building heights. The main finding is the relevant contribution of the use of urban facilities and public services to the overall environmental impact of an urbanized area during its lifespan. The impact of urban planning on the total carbon emissions in cities is shown in the results. The outcome of this research will guide relevant stakeholders in urban development to promote sustainability criteria in urban design guidelines and their inclusion in the policy arena. The results will also help city managers to better understand the role of public services in the overall environmental impact of urbanized areas. [ABSTRACT FROM AUTHOR]

The risks of global warming and the depletion of fossil fuels call for a re-examination of traditional buildings, which have shown satisfactory climate adaptability. Although vernacular dwellings have received considerable attention, few studies investigate other building types. In this paper, the thermal environments of ancient timber-frame halls in northern China were investigated based on field measurements to obtain more evidence of traditional ecological ideology and related strategies. As one of the main types of public buildings in ancient China, six typical halls with different orientations, openings, and ceilings but similar spatial scales and materials were selected; their air temperature, relative humidity (RH), air speed, surface temperature, and globe temperature on typical summer and winter days were measured. The results show that the indoor air temperature of the ancient halls under free-running conditions fluctuated between 22.52 and 29.46 °C in summer and between −8.91 and −2.64 °C in winter, meaning that the indoor environments are comfortable in summer but too cold in winter according to GB/T 50785-2012, which is the Chinese standard for evaluating indoor thermal environments. Further analysis shows that the key strategy for comfort in summer is to have high heat capacity to provide shelter from hot air and solar gains; natural ventilation is considered to be merely an auxiliary approach. Climate-responsive design strategies for winter consist of a south-facing orientation with a maximum window-to-wall ratio and significant thermal insulation to utilize solar gains and to provide shelter from cold air. In addition, the results reveal that ancient halls are limited in their ability to use climatic resources due to technical restrictions. [ABSTRACT FROM AUTHOR]

In this paper a method for separating spikes from a noisy data series, where the data change and evolve over time, is presented. The method is applied on measurements of the total heat load for a single family house. It relies on the fact that the domestic hot water heating is a process generating short-lived spikes in the time series, while the space heating changes in slower patterns during the day dependent on the climate and user behavior. The challenge is to separate the domestic hot water heating spikes from the space heating without affecting the natural noise in the space heating measurements. The assumption behind the developed method is that the space heating can be estimated by a non-parametric kernel smoother, such that every value significantly above this kernel smoother estimate is identified as a domestic hot water heating spike. First, it is showed how a basic kernel smoothing approach is too simple to deliver reliable results. Therefore the problem is generalized to a local least squares problem, which makes it possible to design a robust kernel smoother, which estimate is not affected by the spikes. Furthermore, the generalized model makes it possible to estimate higher order local polynomials. Finally, the results are evaluated and it is found that the method is capable of calculating a reliable separation of the total heat load into the two components. [ABSTRACT FROM AUTHOR]

The paper presents a study of the effect of geometric design of equatorial-facing, double skin façade on energy performance of multi-story office buildings. The investigated parameters relate to the outer skin surface geometry and to the associated air cavity depth between the two skins of this façade system. Two main geometrical designs are investigated. A simple folded plate geometry – saw-tooth that consists of a single fold, and a more complex folded-plate units based on pyramids. The results indicate that although deviation from the basic flat façade leads generally to an increase in heating load, this is counterbalanced by a reduction in cooling load, and a considerable increase in energy generation potential from façade integrated photovoltaic systems. The position of fold and the depth of the cavity have a significant effect on thermal load and energy generation potential. Under the studied climatic conditions (Calgary, Alberta, Canada – 52°N), The total annual electricity generation potential, by the multifold configurations can exceed that of the flat façade by up to 80%. The increase in total electricity generation potential of some designed configurations is accompanied by an increase in time spread of functional electricity over extended period of time. Multifold façade configurations that combine east and west orientations can provide a peak spread of some 4–5 hours. [ABSTRACT FROM AUTHOR]

• Moisture needed to be removed in three building types is calculated. • Salt supported porous composites satisfy most climates and building types. • Zeolites are suitable for return air state, ARI summer and ARI humid climates. • Polyelectrolytes can cope with humid climates and buildings with high wet load. Energy conservation and emission reduction have become a global consensus. As a novel promising energy-saving dehumidification technology, desiccant coated heat exchanger (DCHE)-based air conditioning systems have attracted immense attention recently. This paper provides a quick and reasonable selection of desiccant materials for DCHE systems using water as the cooling medium in different buildings and climates. By the theoretical calculation of moisture needed to be removed in three types of buildings (offices, residential buildings and restaurants) and the analysis of the dehumidification capacity of desiccants in DCHEs reported in the literature, optimal desiccants for different building types and ambient air conditions under given parameters are recommended. Salt-supported porous composite desiccants possess flexible dehumidification performance and can be utilized in most climates and building types, except for extremely humid indoor environments with high requirement for fresh air. Zeolites are especially suitable for return air states, American Air-Conditioning and Refrigeration Institute (ARI) summer and ARI humid climates in buildings with moderate indoor moisture gain, such as offices or residential buildings. Polyelectrolytes can be applied in humid climates and buildings with high indoor wet loads, such as restaurants. This paper offers a promising route to the applications of desiccant materials in novel energy-saving air conditioning technologies. [ABSTRACT FROM AUTHOR]

• This method integrates uncertainty analysis and cluster analysis methods. • Proposed novel zoning indicators are statistically significant. • Moves from traditional weather-based approaches to a performance-based approach. • Robust tool to tackle complex relation between climate and building energy efficiency. • Provide evidence for the rationality of decision making in energy policy. Climatic zoning is an important tool in building energy policy and regulations, smaller and more homogeneous climate zones could help enhance the rationality of energy policymaking. In most countries, climate zoning is based on simplified climate models, and it is difficult to accurately represent the energy demand characteristics of buildings. Therefore, this paper proposes a novel climate subdivision method that tackles the complex relations between climate and building energy-efficient, which move from traditional weather-based approaches to a performance-based approach. Integrate the uncertainty analysis method and the building dynamic performance simulation to extract a novel statistically significant index as the basis for classification. The K -means clustering method and discriminant analysis method are used to obtain and verify the clustering results, respectively. Furthermore, the comparison with clustering results based on degree days confirms the superiority of the new method proposed in this paper in identifying building energy demand. The method is applied to the cold climate zone of China as a showcase. The results show significant differences in building energy demand and the order of key features affecting building performance between each region in the climatic zones. The zone can be further sub-divided into four groups considering the climate factor and building feature uncertainty, and clustering results have been verified by several evaluation indicators. [ABSTRACT FROM AUTHOR]

The absorption or release of heat and moisture by interior surface layers of building envelopes under specific conditions can set effective limits to the extreme levels of indoor air parameters. Moderation of interior climate achieved in this way can contribute to a reduction of energy demands for building conditioning and overall operation cost using a straightforward material solution. In this paper, lime-cement plasters modified by two types of PCM based admixtures are designed specifically for the moderation of relative humidity and temperature fluctuations of the interior environment. The plasters are subjected to a detailed characterization procedure including the assessment of a complex set of basic physical, hygric, thermal and mechanical properties. Experimental results show that the application of small encapsulated PCM particles leads to an up to 10% increase of open porosity, as compared with the reference plaster. Contrary to this fact, the water vapor transport is slightly decelerated, what is attributed to the encapsulating polymer shell which creates impermeable barrier for water vapor transmission. Two contradictory factors affect the liquid water transport, namely the higher porosity of PCM modified plasters and increasing content of not-wettable polymer shells. The moisture storage capacity increases with the increasing amount of PCM in the mix. The moisture buffer value is improved due to the utilization of both PCM admixtures, the developed plasters can be classified as good moisture buffering materials. The thermal conductivity of modified plasters is greatly improved, as well as the heat storage capacity, the additional phase change enthalpy being up to 13 J/g. Although the inclusion of PCM into the lime-cement matrix decreases the mechanical strength, the achieved values of tested mechanical parameters are still satisfactory for the application of the designed plasters in building practice. In summary, PCM modified plasters can be considered a prospective solution for the moderation of interior climate in contemporary buildings. [ABSTRACT FROM AUTHOR]

This paper analyzes the suitability of Gaussian processes for thermal building modelling by comparing the day-ahead prediction error of the internal air temperature with a grey-box model. The reference building is a single-zone office with a hydronic heating system, modelled in TRNSYS and simulated during the winter and spring periods. Using the output data of the reference building, the parameters of a Gaussian process and of a physics-based grey-box model are identified, with training periods ranging from three days to six weeks. After three weeks of training, the Gaussian processes achieve 27% lower prediction errors during occupied times compared to the grey-box model. During unoccupied times, however, the Gaussian processes perform consistently worse than the grey-box model. This is due to their large generalization error, especially when faced with untrained ambient temperature values. To reduce the impact of changing weather conditions, adaptive training is applied to the Gaussian processes. When re-training the models every 24 h, the prediction error is reduced over 21% during unoccupied times and over 10% during occupied times compared to the non-adaptive training case. These results show that the proposed Gaussian process model can correctly describe a building's thermal dynamics. However, in its current form the model is limited to applications where the prediction during occupied times is more relevant. [ABSTRACT FROM AUTHOR]

The Energy Performance of Buildings Directive (EPBD) recast sets out for all Member States the establishment of a comparative methodology framework to calculate cost-optimal levels of minimum energy performance requirements for buildings and building elements. In recent studies, the cost-optimal energy performance of buildings has been calculated in line with the EU's Directive, despite the calculation methodology there mentioned being only a framework that provides a general approach for national calculation methods. This paper defines the parameters needed for the EPBD phasing methodology. The results obtained from the thermal rehabilitation of the building envelope of a Portuguese residential reference building, which are conditioned by the reference building characteristics and by Lisbon's climatic conditions, make it possible to identify the best cost-efficient thermal rehabilitation measures. Conclusions on cost-efficient thermal rehabilitation are as follows: (i) the thermal rehabilitation of the roof produces the greatest variation in the primary energy building consumption (and the floor measures the smallest), (ii) the combination of thermal envelope rehabilitation measures creates synergy effects that lead to better results than single measures (regarding global costs and primary energy consumption), and (iii) it is more advantageous to proceed with a thermal rehabilitation package of measures rather than doing nothing. [ABSTRACT FROM AUTHOR]

Abstract: Double-skin façade (DSF) buildings have been developed and used in both new and renovated buildings to increase human comfort and decrease energy consumption. Daylighting in DSF buildings has received less attention compared ventilation strategies. This paper aims to evaluate the daylighting characteristics of 12 existing DSF systems that are exposed to different climates by using the IES simulation software. The protocol was applied to south-facing models under overcast sky conditions and was implemented under different outdoor illuminance. Different designs of DSF systems significantly affect the indoor illuminance values inside the office. At the office entrance, the indoor illuminance values are free of glare. All DSF models fail to meet the standard indoor illuminance requirement of at least 200lx within 75% of the office space. Among all the DSF models, the percentage of the office space covered with at least 200lx are found in the range of 40–68%, 13–52%, and 5–30% at an outdoor illuminance of (19,000, 12,000, and 6000)lx, respectively. At an outdoor illuminance of 19,000lx, the studied DSF systems from subtropical climates show the best daylighting characteristics and are potential subjects for further optimization. Based on the assumptions of this case study, daylighting analysis shows that the existing 12 DSF systems do not follow daylighting strategies. [Copyright &y& Elsevier]

Abstract: A number of metrics for assessing human thermal response to climatic conditions have been proposed in literature over the last decades. They aim at describing human thermal perception of the thermal environment to which an individual or a group of people is exposed. More recently, a new type of “discomfort index” has been proposed in scientific literature, in standards and in guidelines for describing, in a synthetic way, the long-term thermal comfort conditions in buildings and for predicting uncomfortable phenomena. Most of these new indices synthesize the thermal performance of a building in a single value. We present in this paper a systematic review of 15 indices for the long-term evaluation of thermal comfort conditions in a building. They are here grouped in a limited number of homogenous families according to the assumptions on which they are derived and then they are analyzed according to some key aspects in order to identify their scope, their strengths and weaknesses. Finally, some guidance is provided for future developments. [Copyright &y& Elsevier]

Abstract: Greening the building envelope focusing on green façades with vegetation is a good example of a new construction practice. Plants and partly growing materials in case of living wall systems (LWS) have a number of functions that are beneficial, for example: increasing the biodiversity and ecological value, mitigation of urban heat island effect, outdoor and indoor comfort, insulating properties, improvement of air quality and of the social and psychological well being of city dwellers. This paper discusses a comparative life cycle analysis (LCA) situated in The Netherlands for: a conventional built up European brick façade, a façade greened directly, a façade greened indirectly (supported by a steel mesh), a façade covered with a living wall system based on planter boxes and a façade covered with a living wall system based on felt layers. Beside the environmental benefits of the above described greening systems, it is eventually not clear if these systems are sustainable, due to the materials used, maintenance, nutrients and water needed. A LCA is used to analyze the similarity and differences in the environmental impacts in relation with benefits estimated for two climate types for building energy saving (reduction of electrical energy used for building cooling and heating). [Copyright &y& Elsevier]

Abstract: In Thailand, traditional houses and public buildings were constructed from materials of low thermal mass. Windows and doors in such buildings are well shaded. Open windows, doors, and even gaps in the raised floor allow all interior spaces in a building to be naturally ventilated. Prior to the introduction of air-conditioning, concrete began to replace wood as walling material. New large air-conditioned buildings have glazed and closed windows so all interior spaces require air-conditioning and forced ventilation. Under the present situation, there is a tendency to believe in the merit of thermally massive walls. This paper presents results from an experimental and simulation study on comparative energy and economic performance of thermally light and massive walls that are used to enclose air-conditioned spaces. The spaces are assumed to serve three residential functions and three commercial functions. Results related to residential functions reaffirm the merits of vernacular architecture. Results related to commercial functions are mixed. However, very massive walls are not economical. [Copyright &y& Elsevier]

Abstract: For low-rise buildings, the heat losses or gains through the ground coupled building envelope can be a significant load component. Studies have shown that current simulation tools give dissimilar results for the ground coupled heat transfer (GCHT) with basements. This paper quantifies and explains the differences between EnergyPlus and DOE-2.1e (DOE-2) basement GCHTs based on their results for an all electric code house in a hot and humid climate zone. The code house was modeled with two basement configurations i.e. a conditioned basement and an unconditioned crawlspace. DOE-2 was used with Winkelmann''s basement model and EnergyPlus was used with its GCHT calculator utility, Basement. The results revealed that the ground isolated EnergyPlus houses used 3–23% more cooling, 12–29% less heating and 3–7% lower overall HVAC electricity use when compared to the ground isolated DOE-2 houses. Ground coupling added up to three times more heat loss in EnergyPlus than in DOE-2. This increased the overall energy use difference between these two programs from 3–7% (ground isolated) to 14–25% (ground coupled). These results showed that a truth standard is required for basement heat transfer calculations of low-rise buildings. [Copyright &y& Elsevier]

Abstract: Vernacular architecture is still very popular and constructed widely in North-East India. In this paper, the result of long-term monitoring of two vernacular houses selected one in Tezpur (warm and humid climate) and other one in Cherrapunjee (cold and cloudy climate) are presented. Long-term monitoring work includes the measurements of temperature (inside and outside house), relative humidity (inside and outside house) and illumination level (inside and outside house) for 25 days in all the seasons (January: winter, April: spring/pre-summer, July: summer/monsoon and October: autumn/pre-winter) of the year 2008. Temperatures profile across all the seasons represents strong daily and seasonal fluctuations. Formulae have been developed based on part of the monitoring data to predict the indoor maximum, average and minimum temperatures inside the same house occupied by the same family. The predicted formulae were developed based on the measured data for the month of January and July and were validated with the measured data of April and October months. It is found that the correlation coefficient (R 2 value) is above 0.96 for all the six formulae for the entire monitoring period. [ABSTRACT FROM AUTHOR]

Abstract: Increased awareness on environmental issues, together with requirements imposed by implementation of energy efficiency codes, has generated the need for tools that evaluate thermal performance of buildings. Their objective is to ensure compliance and certification. However, existing computer models are still rudimentary with many limitations for use in early design stages of any architectural project. They require exact data in a stage when designers consider conceptual ideas from a range of options rather than precise details and numbers. Design tools that suggest solutions based on ideas are rare. This disadvantage can be seen in the planning of intelligent facades, where the number of possible configurations can be overwhelming and decisions made in early stages have profound effects on energy and comfort performance. This paper presents NewFacades, a model that helps pass from ideas to significant concepts in the design of intelligent facades. It uses energy and visual comfort strategies abstracted from a prescriptive energy code for hot climates to suggest a range of good starting solutions. Designers can have energy and visual comfort estimations to these alternatives through an advanced stage energy simulation program such as EnergyPlus, or explore them further with other tools. Methods used by the tool are presented here in the context of sample cases. By working on energy principles or relying on local existing energy standards, the model can be extended to all types of climates. [Copyright &y& Elsevier]

Abstract: The main requirements of European Directive 2002/91/EC on the energy performance of buildings (EPBD) are the application of minimum energy performance requirements for new buildings and certification of the energy performance of buildings. Its transposition into the national law of member states of the European Union has signified the appearance of new and more onerous requirements in terms of construction quality from the point of view of energy performance, and in terms of the procedure for certification of the energy performance of buildings. In both cases, the levels required tend to be based on climatic conditions, fundamentally in countries such as Spain, where the climatic variability is very pronounced. This paper presents a methodology developed for the climatic zoning of the localities not included in the above-mentioned regulations in order to facilitate their application. By way of example, the method is shown which was used to generate the climatic files and carry out the subsequent climatic zoning of all the municipalities of the region of Andalusia in southern Spain. [Copyright &y& Elsevier]

Abstract: There are few countries in the world where they have special characteristics including weather conditions, wind direction, and topography. In other words, some countries have multi-climate regions, and needed to be investigated more precisely. Based on these conditions, several cooling systems can be used for each region. In this study, the potential of the direct evaporative cooling (DEC) systems, indirect evaporative cooling (IEC) systems, desiccant wheel (DW) with DEC systems, and combination of theses methods for cooling in the cities of Iran are investigated. In the remaining regions, mechanical cooling systems and absorption systems can be used. According to weather condition and natural resources for water in Iran, DEC can be considered as a serious alternative for cooling. In this paper, based on numerical simulation and long-term meteorological measurements, general set of criteria is obtained. Results show that according to population dispersal DEC systems can provide comfort conditions for 53% of people of Iran. IEC, DW, combination of these systems, and mechanical cooling systems can supply comfort condition in remaining major cities of Iran consequently. Moreover, for showing the uniqueness of weather condition which leads to these varieties of climates, other important cities in the neighboring countries are compared with this numerical simulation code. [Copyright &y& Elsevier]

Abstract: There is evidence from the International Panel of Climate Change that the UK will experience a mean rise in ambient air temperature over the coming years. Such a rise in temperature will change the requirements for heating and cooling of domestic buildings. This scoping paper explores this issue with respect to the housing sector in the Yorkshire Humber Region of the UK and comes to the conclusion that the regions domestic sector poses major problems with respect to the stated carbon savings required by the UK Government. [Copyright &y& Elsevier]

Abstract: The heat consumption in a large geographical area is considered together with climate measurements on a single location in the area. The purpose is to identify a model linking the heat consumption to climate and calendar information. The process of building a model is split into a theoretical based identification of an overall model structure followed by data-based modelling, whereby the details of the model are identified. This approach is sometimes called grey-box modelling, but the specific approach used here does not require states to be specified. Overall, the paper demonstrates the power of the grey-box approach. [Copyright &y& Elsevier]

The energy required to create a comfortable living environment in high-density cities in hot and humid climates usually demands a substantial electricity usage with an associated environmental burden. This paper describes an integrated passive design approach to reduce the cooling requirement for high-rise apartments through an improved building envelope design. The results show that a saving of 31.4% in annual required cooling energy and 36.8% in the peak cooling load for the BASECASE apartment can be achieved with this approach. However, all the passive strategies have marginal effect on latent cooling load, often less than 1%. [Copyright &y& Elsevier]

Commenting on some negative effects of traditional conditioning strategies of indoor thermal environment in warm climates, the authors present a fundamental concept of thermal comfort and acceptability, new air-conditioning strategies by using fluctuating air movement based on the findings of human responses to transient thermal environment, and a prediction of energy saving caused by elevated indoor temperature settings. In addition, how to meet the requirement of providing human-beings a healthy, comfortable and affordable indoor air temperature, and to achieve a goal of sustainable development are also discussed in this paper. [Copyright &y& Elsevier]

• Investigation of two residential buildings in a sub-Arctic region. • One building subject of energy-retrofit, one maintained the original envelope. • No significant improvement to the heat supply after energy efficiency measure. • The thermal indoor climate showed signs of overheating. • The heating system should be reviewed when an energy-retrofit is done. There is a need to improve the understanding and the knowledge of energy efficiency measures for residential buildings in sub-Arctic climate regions. This paper presents an investigation of two identical multi-family residential buildings in the sub-Arctic climate of northern Sweden, before and after renovation. During the renovation, additional insulation of the external walls and new windows were installed in one building, while the other building retained its original envelope. The energy usage data for the past four heating seasons were collected, including data from before and after the renovation. Detailed thermal indoor climate data were gathered for specific months. The data from the two separate buildings showed that the renovation did not result in a significant improvement in energy usage. Prior to the renovation, the energy usage data showed a difference of 2–3% in the heat supply between the two buildings, and this difference persisted after the renovation. On the other hand, the indoor air temperature was raised. The renovated building had an indoor air temperature which was 2 °C higher than the not yet renovated building. IDA ICE models were constructed and validated with the measured data to investigate how a lower indoor air temperature would affect the energy usage and indoor thermal climate. The models showed that with a reduction in the indoor air temperature by 2 °C after the renovation, the thermal climate would maintain an acceptable level according to PMV/PPD standards, and would result in a 13–14% reduction of the heat supply during the cold months. With an annual reduction of 15%, the heat supply could be reduced by 270 MWh per year for the whole area where the buildings are located. This clearly demonstrates the importance of adjusting the heating system after an energy efficiency measure has been performed. [ABSTRACT FROM AUTHOR]

Buildings are responsible for a large share of the energy demand and greenhouse gas (GHG) emissions in Europe and Switzerland. Bottom-up building stock models (BSMs) can be used to assess policy measures and strategies based on a quantitative assessment of energy demand and GHG emissions in the building stock over time. Recent developments in BSM-related research have focused on modeling the status quo of the stock and comparatively little focus has been given to improving the modeling methods in terms of stock dynamics. This paper presents a BSM based on an agent-based modeling approach (ABBSM) that models stock development in terms of new construction, retrofit and replacement by modeling individual decisions on the building level. The model was implemented for the residential building stock of Switzerland and results show that it can effectively reproduce the past development of the stock from 2000 to 2017 based on the changes in policy, energy prices, and costs. ABBSM improves on current modeling practice by accounting for heterogeneity in the building stock and its effect on uptake of retrofit and renewable heating systems and by incorporating both regulatory or financial policy measures as well as other driving and restricting factors (costs, energy prices). [ABSTRACT FROM AUTHOR]

In this paper, a new approach to study the impact of the climate on the optimal sizing of a stand-alone PV/hydrogen/battery-based hybrid building is presented. A general method is described to evaluate the thermal need of the building, as well as the local photovoltaic resource, rather than using specific data available for large purpose applications. The proposed approach enables comparison studies between different places and climatic conditions. Considering a specific autonomous building, a comparative study is provided for different areas worldwide: Moscow, Cairo, Paris, Hanoi and Montreal. A Genetic Algorithm is used to provide an optimal size and energy capacity estimation for each location. The objective is to minimize the total cost while constraining the Loss of Power Supply Probability (LPSP) and the State of Charge (SoC) of the long-term storage element over one year. The sizing results between the different places demonstrate that the local climate has a huge impact on the final price, by highly modifying the PV resource and the thermal need of the building. The results demonstrate an 80% increase variation of the total installation cost between the area of Montreal and the one of Cairo. [ABSTRACT FROM AUTHOR]

This paper evaluates the potential of water-side economizers in the refrigeration system of data centers under different climate conditions. Due to the wide range of conditions along the country (Desert, Mediterranean, Temperate rainy and Tundra climate), Chile is selected as case study. The number of hours per year in which economization is possible is estimated using the data base of 22 weather stations along the country. The refrigeration system is modeled in steady state through a set of thermodynamic equations simultaneously solved using the Engineering Equation Solver (EES). The system performance is evaluated by calculating the Coefficient of Performance (COP) and the Water to Energy Ratio (WER). The latter is a new metric proposed to compare the volume of water required by the system to save 1 MWh of cooling energy. The thermodynamic analysis shows that the chiller decreases its energy usage if water-side economizers are implemented in favorable climates such as cool-summer Mediterranean with winter rain (Csc), temperate rainy (Cfb) and tundra (ET) climates. Here, the use of economizers allows a monthly increase in the COP of 50 to 120% (compared to the conventional operation) and an annual average COP ranging from 7.8 to 9.7. These climates also offer an additional gain of lower water requirements, with annual WER values ranging from 11 to 17 m3/MWh. Desert climates, on the other hand, prevent implementing economizers, offering the lowest annual average COP values (5.6–5.7). In climates in which the complete economization is impossible, the partial use of economizers allows a monthly increase in the COP of 10 to 45%. The costal influence decreases the system performance, reducing the COP and increasing the WER. [ABSTRACT FROM AUTHOR]

• A coupled simulation model of urban microclimate and building energy is developed for high density cities. • Reason agreements were observed between predicted air temperature and measurement data. • Air temperature in street canyons can rise 1–3 ºC on average above the ambient in summer. • Anthropogenic heat dominates temperature rise in street canyons in high density cities. • Temperature rise in street canyon can increase building cooling demand by 15% in summer. The energy performance of a building in a dense city depends to some extent on its surroundings. The impact of the built form, together with anthropogenic heat gains from traffic and building HVAC exhaust, determines external environmental conditions at the Urban Canopy Layer. Existing building energy models are limited in accounting for micro-scale variations of the urban microclimate, which may significantly modify a building's energy performance in density cities. This paper presents the Urban Building Energy and Climate (UrBEC) model, a coupled urban microclimate model (UMM) and building energy model (HTB2) developed to assess the time varying energy performance of a cluster of buildings and the combined heat gains to the external space from direct and reflected solar radiation, traffic and the exhaust from HVAC systems in a high-density city. The simulation results were evaluated by comparison with field measurement data collected from the Sai Ying Pun neighbourhood in Hong Kong, on a summer and winter day. Predicted and measured air and surface temperature at the four locations were found to be in reasonable agreement. Simulation results indicate an average of 1-3 ºC of temperature rise in street canyons compared with the ambient air in summer. Street level air is predicted to be 0.6 ºC warmer than those at higher levels (20m +). Anthropogenic heat from traffic and building HVAC exhaust are the dominant contributors to temperature rise in street canyons in summer, exceeding the contribution from urban surfaces. The predicted building cooling demand is expected to increase up to 15 % in summer due to the warming effect in street canyons. The UrBEC model runs significantly faster than current CFD-based approaches. Therefore, the model has the potential to support early stage design and planning decisions in a dense city. [ABSTRACT FROM AUTHOR]

Neglecting extremes and designing buildings for the past or most likely weather conditions is not the best approach for the future. Robust design techniques can, however, be a viable option for tackling future challenges. The concept of robust design was first introduced by Taguchi in the 1940s. The result of the design process is a product that is insensitive to the effect of given sources of variability, even though the sources themselves are not eliminated. A robust design optimization (RDO) method is for the first time proposed in this paper, for supporting architects and engineers in the design of buildings with robust energy performance under climate change and extreme conditions. The simplicity and the low computational demand of the process underlies the feasibility and applicability of this method, which can be used at any stage of the design process. The results show that the performance of the optimum solution not only has a 81.5% lower variation (less sensitivity to climate uncertainty) but at the same time has a 14.4% lower mean energy use value compared with a solution that is compliant with a recent construction standard (ASHRAE 90.1-2016). Less sensitivity to climate uncertainty means greater robustness to climate change whilst maintaining high performance. [ABSTRACT FROM AUTHOR]

Climate change motivates the pursuit of more efficient solutions for heating and cooling of buildings in order to reduce greenhouse gas emissions. While many investigations have been made into how efficiencies can be improved on a technology level, far less are present for how climate change affects the future heating and cooling demand. In this paper, we analyze the extent in which global climate trends change the theoretical heating and cooling demand of buildings. The results are based on the link between heating and cooling of buildings versus climate, and the definition of steps leading from climate to energy consumption. Three different climate scenarios are considered by using the EURO-CORDEX simulations for the case study of Swiss heating and cooling demand. The most severe climate scenario RCP8.5 leads to a −40% decrease of heating degree days and a + 1300% increase of cooling degree days by the end of the century. The presented results can be used for energy system models and for future building design criteria. [ABSTRACT FROM AUTHOR]