bluuebunny/crossref_metadata_2025 huggingface dataset:
Manufacture of optimized PCM within thermal comfort range to improve building energy performance
Authors: Hun Park Ji , Wi Seunghwan , Lee Jongki , Yeol Yun Beom , Yang Sungwoong , Kim Sumin
Published: October 2019

The objective of study is to manufacture the optimized PCM within thermal comfort range to improve thermal performance and building energy performance. In order to prepare the melting temperature of PCM close to the thermal comfort range, n-octadecane (OT), n-heptadecane (HT), and n-hexadecane (HX) were selected. According to the circulation water bath test to investigate the melting temperature of PCM, the mixed PCMs of OT and HT (OTHT) with 22 to 23 °C were close to the thermal comfort range. In addition, the circulation water bath test of OTHT depending on various mixing ratio, divided into ratios of 9:1 to 1:9, was conducted to evaluate the ideal PCM melting temperature. As a result, melting temperature of OTHTs were measured to be 24 to 26 °C, 23 to 24 °C, 22 to 23 °C, 21 to 23 °C, and 20 to 22 °C, respectively. According to the analysis of thermal performance of OTHTs, OTHT91, where phase change temperature appeared at 24 to 26 °C, were the optimized PCM due to the highest latent heat capacity and ideal melting temperature within thermal comfort range. This indicate that building materials with application of OTHT91 can contribute to reducing building energy consumption and improving thermal comfort of occupants when the indoor condition in buildings is maintained at thermal comfort range.
Application of the ecological valency concept to buildings’ environmental control systems
Authors: Mahdavi A , Teufl H , Berger C
Published: October 2019

Buildings are typically equipped with a number of elements and devices (such as windows, blinds, luminaires, radiators, and fans) to control indoor environmental conditions. The availability, effectiveness, and usability of control devices and their human interfaces constitute arguably an essential aspect of built environments quality and performance. We refer to this aspect as buildings’ indoor-environmentally relevant “ecological valency” (EV) or the “affordance”. It can be interpreted as a descriptor of buildings’ responsiveness toward inhabitants’ needs and requirements. Despite its critical importance, there is currently a lack of systematic evaluation or certifications procedures for objective characterization of indoor environments’ EV as related to the availability and effectiveness of control devices and their human interfaces. The present contribution explores thus the potential for designing and implementing formal procedures toward measurement and certification of indoor environments’ EV.
Modelling drivers of variance and adaptation for the prediction of thermal perception and energy use in zero energy buildings
Authors: Schweiker Marcel
Published: October 2019

As thermal perception is a subjective “condition of mind”, a high variance in observed thermal sensation votes does not come to a surprise. Literature reviews show a large number of individual and contextual influences. However, the quantification of the effect of individual drivers on thermal perception as well as thermal adaptation and their integration into thermal comfort models is still an open field of research. Still, analyses of the energy balance of zero-energy buildings (ZEB) are using assumptions related to the user’s needs e.g. in terms of thermal comfort. First, this paper explores a novel combination of a biophysical model and an adaptive framework (called the ATHB*TNZ approach) and discusses the applicability of such approach to model individual differences in thermal perception. Second, results of an implementation of these individualized comfort prediction on the energy balance of a zero energy building are presented together with the resulting discomfort hours. Results show that the consideration of physiological differences and adaptive processes in the modelling approach can replicate observed variations in thermal perception. The energy balance of a ZEB is hardly affected by set point adjustments due to individual requirements, but discomfort hours strongly depend on individual characteristics of occupants.
Prefabricated and low impact residential modules: comparative analysis between ventilation systems
Authors: Cascone S M , Russo G , Tomasello N , Vitale M
Published: October 2019

The recent natural and anthropic disasters have led some of today’s experimental researches to be oriented towards the study of residences for temporary living. During an emergency, the lack of primary resources and services often forces part of the affected population to live in inadequate health and environmental conditions. These problems are aggravated by the psychological damage to which the displaced people are subjected, as well as by the temporary nature of the residence. The temporary residence project should respect different requirements, e.g. construction speed, the ease of transport and the flexibility of the interior spaces. The aim of the present research is to improve the internal comfort of modular and prefabricated living areas designed for emergencies, through the application of a controlled mechanical ventilation system. The study aims to develop combinable and transportable modules that allow to obtain multiple spatial and planimetric combinations of accommodation thanks to an easy and quick junction system, the same for almost all panels. The easy assembly and disassembly as well as the ease of transport make these modules reusable and easy to install, fundamental characteristics as different emergency situations can occur in places very distant from each other. To achieve the required performance, a controlled mechanical ventilation system has been designed to make the modules adaptable to any environmental and climate context. A comparative analysis was carried out between a mechanical ventilation system and natural ventilation. For the mechanical ventilation an autonomous system for each module was chosen compared to a centralized system with ducts distributed in the house. The proposed solution allows to guarantee an adequate level of air health, without a significant increase of the associated costs.
Intervention field study in the Canadian arctic: Improving ventilation, indoor air quality, and the respiratory health in Nunavik dwellings and children
Authors: Aubin D , Ouazia B , Poulin P , Levesque B , Tremblay F , Boulet L-P , Duchaine C , Degois J , Maltais F , Brisson M , Savignac M
Published: October 2019

Homes with inadequate ventilation and indoor air quality (IAQ) are particularly common in northern and remote communities. Previous studies have observed that the indoor air in these homes can have elevated concentrations of CO2, environmental tobacco smoke, and elevated relative humidity leading to mold issues. These conditions may cause various health problems, such as compromised respiratory health for the occupants and in particular in children with developing respiratory systems. The objectives of this current study were to measure the effectiveness of a targeted optimization of existing heating and ventilation systems at improving ventilation, IAQ, and the respiratory health of children. This study enrolled homes with children under the age 10 in both an intervention group and control group over the winter and spring of 2017-18 in Kuujjuaq, Québec, Canada. Various IAQ, ventilation, and behavioural characteristics were measured both before and after the intervention. Following the intervention, we observed statistically significant reductions in the median values a number relevant IAQ parameters. This study demonstrated that targeted preventative maintenance and optimization of ventilation systems can significantly improve ventilation rates and IAQ.
Performance of surface fluorinated P25-TiO2 on the photocatalytic degradation of volatile organic compounds in indoor environment
Authors: Shayegan Zahra , Haghighat Fariborz , Lee Chang-Seo
Published: October 2019

Volatile organic compounds (VOCs) are considered as a major group of indoor air contaminants with several adverse health effects. Photocatalytic oxidation process (PCO) has been applied for the removal of indoor VOCs. In the PCO process, the adsorption extent of water molecules on the surface of photocatalysts is a decisive factor for PCO efficiency. Water molecules contribute in PCO process either as; a) the main hydroxyl radical’s source and enhance the removal efficiency, or b) compete with VOCs to adsorb on the super-hydrophilic surface of P25 and reduce the photodegradation efficiency. In this study, the effects of surface fluorination on the photoactivity and surface hydrophilicity of commercial P25 were investigated. The fluorinated P25 (F-P25) nanoparticles were synthesized to remove methyl ethyl ketone (MEK) from the indoor environment. Surface fluorination formed the surface ≡ Ti – F by an exchange reaction between the surface hydroxyl groups (OH) and fluoride ions (F−) and decreased the water vapor adsorption on the photocatalyst’s surface. Herein, the photocatalytic efficiency of F-P25 was compared to P25 under a continuous-flow condition with a small residence time (0.026 sec) at four different relative humidity levels (0, 20, 40, and 60%). Furthermore, the performances of F-P25 and P25 on the generation of by-products, including formaldehyde and acetaldehyde were also evaluated. The results revealed that the F-P25 enhanced the photodegradation of MEK compared to bare-P25 in all tested relative humidity levels; however, the generation of the by-products increased as relative humidity increased.
Evaluation of the occupants’ exposition to the indoor environment.
Authors: Wladyslaw Dziedzic Jakub , Yan Da , Novakovic Vojislav
Published: October 2019

User behaviour has a significant contribution to the final energy consumption figures of buildings. As indicated in finding from the IEA EBC Annex 66 project, proper and continuous monitoring of occupant behaviour inside buildings can support reaching of the zero energy-building standard (ZEB). The collected data, however, must be gathered via in situ methodology to avoid potential influences on data quality. Commonly used measurement techniques such as plug-load monitoring, CO2 level sensing or PIR, are sufficient to describe energy-related occupant behaviour at the zone/room level. However, this resolution of description can only be treated as an energy consumption overview as it cannot guarantee an identification of individual indoor environment quality preferences. Development of a solution that can grant access to an individual description of occupant needs requires direct monitoring of their inside building activity. Herein, access to necessary input data can be provided with the use of the depth registration camera because the suggested measuring technique can deliver information about routine occupant positioning inside each zone/room. Additionally, it provides data about the position of the observed occupants’ body limbs. If information about the distribution of the occupants is delivered, it is possible to couple such with a result matrix obtained via CFD studies. Moreover, the coordinates of occupant limb positions can be used as a data-probing device in simulation studies. With such a tool, it will be possible to monitor the exposure of each limb to the thermal properties of indoor air. Collecting data through this methodology can grant access to a more profound understanding of the occupant thermal comfort sensation and the habits that influence building energy use.
Appropriate technology to improve thermal performance of existing window
Authors: Lee Suin. , seok Choi Gyeong , jung Choi Hyun , sik Kang Jae
Published: October 2019

Technological development for reduction of CO2 emissions has been actively carried out globally. In buildings, windows and envelops are the parts that generate the greatest heat loss. Therefore, it is the target to improve primarily for the energy efficiency. Various techniques such as vacuum glass and heat-insulating reinforced frame have been developed to improve the thermal performance of windows, however, these techniques can be applied only for new windows. To apply these technologies, it is necessary to install them in a building on construction or to replace all of windows of existing building. In this paper, we developed the technology to improve the thermal performance of existing windows. This technology can be applied without any movement of occupants or furniture. Moreover, it is affordable, durable and available for everyone without any special expertise or tools. Another benefit of this technology is that it does not affect daylighting and view since it has a high transmittance. In order to verify the performance of it in terms of the thermal aspect, the mock-up experiment and the field test were conducted. Thermal transmittance of windows was measured and analyzed before and after improving their thermal performance with the technology. The result shows that the values of the thermal transmittance of windows have improved by 20% after application of the technology.
Active coating including microorganism for indoor formaldehyde degradation
Authors: Senechal T , Castro C C , Viseur J , Ducoulembier A , Hantson A-L , Lahem D
Published: October 2019

Indoor environmental contamination of residential units and workplaces is a major problem that needs efficient, durable and environmentally friendly solutions. The development of active coatings capable of entrapping and degrading selectively pollutants such as formaldehyde is herein proposed. Freeze-dried Pseudomonas putida sp. cells were introduced in sol-gel coatings. Precursor ratio, thickness and water content of the coatings were the parameters used to optimize their effectiveness on formaldehyde degradation. Although with different abilities, bacterial cells immobilized into the distinct sol-gel formulations were able to degrade formaldehyde. The presence of 3-glycidoxypropyltrimethoxysilane and polyethylene glycol in the sol-gel promoted the enzymatic degradation of formaldehyde as they provide the stability of the humidity of the coatings and so, the well-being of the cells. Storage temperature and time proved to be important variables for keeping the enzymatic activity of degrading-microorganisms incorporated in the sol-gel coatings. Coating formulations promoting the higher abilities to degrade formaldehyde provided also good mechanical properties.
Optimizing Indoor Environmental Quality in hot arid climates
Authors: Wagdi Dalia , Tarabieh Khaled , Grant Phillipa
Published: October 2019

Indoor Environmental Quality (IEQ) is a key indicator of the quality of the built environment and the health of its occupants. The purpose of this study is to investigate a range of IEQ parameters in buildings located in hot, arid climates, representing some of the recurring challenges in offices. The study aims to identify the main IEQ factors and their acceptable ranges, including light, thermal comfort, air quality and noise. An IEQ index is utilized (Wagdi et. al 2017) as a tool which assesses the predefined IEQ parameters in office buildings providing a rating scheme which aggregates the obtained readings. Data collected from offices located in Dubai and Cairo is used to assess the indoor environment against defined benchmarks. The full range of parameters was monitored in a group of office spaces and the obtained readings were used to compute the IEQ index. For this investigation, all offices were completely fit out and tests were performed after at least one month of operation. The recorded results demonstrate that with careful design and informed material selection, acceptable IEQ levels can be achieved. The results and application of the index aim to provide an assessment tool to optimize design and construction practices, ultimately improving employee productivity, comfort and health.
An improved integrated comfort control algorithm with cooling and ventilation systems to maintain indoor relative humidity
Authors: Ho Kim Sun , Ran Yoon Young , Won Kim Jeong , Jun Moon Hyeun
Published: October 2019

This study evaluates an improved Integrated Comfort Control (ICC) algorithm with an air conditioner and ventilator system that considers the outdoor environment to ensure appropriate indoor thermal comfort for occupants. In this investigation, the ICC algorithm has been improved to maintain acceptable indoor humidity levels within a comfortable range using a ventilation system. To evaluate this algorithm, we performed experiments and simulations in a virtual testbed. In Case 1 (mild and humid outdoor air) and Case 2 (hot and humid outdoor air), the comfort ratios increased from 0% to 52.1% and from 0% to 45.0%, respectively, with the improved ICC algorithm. The evaluation results show that the improved ICC algorithm can help indoor conditions to reach a defined comfort range quickly and maintain these conditions well.
Modelling and optimization of helical steel piles as in-ground heat exchangers for Ground-Source Heat Pumps
Authors: Nicholson Sarah R , Mwesigye Aggrey , Dworkin Seth B
Published: October 2019

Ground source heat pumps are a sustainable way to provide building heating and cooling due to their efficient use of near-constant ground temperatures as mediums for heat exchange. Conventional in-ground heat exchangers are limited by the large size of required borehole field installations and the high economic costs, therefore the pairing of in-ground structural helical piles with these heat exchangers offers a system of geothermal heating and cooling which can be more accessible and lower cost than traditional equipment. In this research, a novel helical steel pile was modelled using a 3-D numerical model and finite element analysis. This model was first validated with experimental data from a double-tube pile, with 24-hr transient operation outlet temperatures accurate within 3%. Finally, the steady state heat exchange rate per unit area was calculated, with the new helical steel pile geometry yielding an increase of 8.6 W/m, 13.2 W/m, and 16.2 W/m (for 2 L/min, 4 L/min, and 8 L/min flowrates respectively) over the validation model.
Research on the influence of coal to electric heating on regional power grid in Northern China
Authors: Ding Xingli , Ma Rongjiang , Shan Ming , Rong Xing , Wang Xianlin , Yang Xudong
Published: October 2019

North china has been implementing large-scale coal-to-electricity action, for air pollution reduction and rural household indoor environment improvement. This cause electricity fluctuations and load increase. This paper characterizes patterns of three dominated electric heating equipment in Beijing-Tianjin-Tangshan region (BTT), which are thermal storage electric heating radiators (TSEHRs), air-to-water heat pumps (AWHPs), and low temperature air-to-air heat pumps (AAHPs), and estimate their impact on the power grid system of BTT. Due to physical properties, TSEHRs keep operating as a direct-acting electric heating radiator during the daytime, consequently, caused a high electricity consumption up to 144.3 (kWh/m2); AWHPs had to uninterrupted operate to keep heating each currently in-use room, and electricity consumption was 65.6 (kWh/m2); electricity consumption of AAHPs fell to 29.7 (kWh/m2), benefited from separate installation and intermittent operation. Based on those patterns, the impact on power grid system of large scale adoption in BTT were estimated: daily peak-valley ratios of the typical daily load curve, which respectively turned into 42.5%, 22.4%,21.8% from original 26.5%, and the load increase rates of the original monthly maximum load throughout the year, respectively were 101.5%, 9.0%, 2%.
Simulation and analysis of load shifting and energy saving potential of CO2-based demand-controlled ventilation in a sports training center
Authors: Heidar Esfehani Hamidreza , Schäuble Jakob , Paul Elena , Bohne Dirk
Published: October 2019

This paper aims to evaluate and characterize the impact of optimizing the operation of the HVAC system through maintaining dynamic CO2-based Demand-Controlled ventilation (DCV) on the electricity load profile and energy consumption of the sports training center of Leibniz University Hannover. The actual ventilation control scheme, in which the operation of the HVAC system is operated with a two-stage volume flow controller based on indoor CO2 concentration is improved through two steps to avoid overventilation and reduce power consumption. For this purpose, a detailed multi-zone model of the sports center and energy supply system has been developed in TRNSYS. In the first step, a multi-stage control scenario is implemented considering the occupancy schedules and indoor CO2 concentration measurement data. In the second step, based on an indoor CO2 concentration model, a predictive control scenario is developed and applied. Aiming at characterizing the influence of these operation scenarios on the power consumption of the building, the annual electricity load profiles of the simulation cases will be analyzed and compared with the actual load profile of the building based on the technical planning documents and data provided by building management system (BMS). Simulation results show that utilizing predictive CO2-based DCV leads to a reduction of the peak load electricity by almost 2 kW and the base load by 5 kW as well as decreasing the annual energy consumption by 40 %.
Building-to-vehicle-to-building approach for the NZEB target at a micro-grid level: a comprehensive sensitivity and parametric post-optimality analysis
Authors: Barone Giovanni , Buonomano Annamaria , Forzano Cesare , Palombo Adolfo
Published: October 2019

This paper focuses on a novel energy management approach for cluster of buildings connected in micro-grids by taking advantages from plug-in electric vehicles considered as vector devices for renewable energy exchanges, besides additional high-power appliances and house electricity sources. Such approach allows accelerating the development of nearly zero energy buildings and promoting the deployment of renewable energy sources at a micro grid level. To this aim, a dynamic simulation model, implemented in MatLab was developed for the building energy demands and loads assessment. To show the potentiality of the considered concept and approach, a case study based on a micro-grid consisting of a house and an office building connected by an electric vehicle is presented. The optimization of three different layouts, where electricity is alternatively produced by tilted roof or vertical façade photovoltaic panels is conducted by means of a parametric analysis performed by varying the vehicles energy use, battery capacities and solar field size. Preliminary results show that, by considering economic criteria, by exploiting the renewable energy production on and off-site, the buildings final demands decrease to values lower than those commonly considered for NZEBs.
Experimental assessment of the combined effect of retroreflective façades and pavement in urban canyons
Authors: Castellani Beatrice , Nicolini Andrea , Gambelli Alberto Maria , Filipponi Mirko , Morini Elena , Rossi Federico
Published: October 2019

Retro-reflective (RR) materials represent an opportunity to reduce UHI phenomenon due to their ability to reflect most of the incident energy towards the same incoming direction. The RR behaviour depends on the angular distribution of the incident energy: for small incident angle the radiation is reflected mainly backward in the incoming direction; for large angles RR materials reflect the radiation symmetrically with respect to the surface normal. To overtake the limit of RR materials of being mainly retroreflective only for small angles of incidence, the investigation is focused on the optic interaction between vertical and horizontal RR surfaces. Therefore, the aim of this paper is to investigate the synergic effect of RR pavements and façades on a physical model in which urban canyon layouts with H/W equal to 1 and 2 are represented. To evaluate the global cooling effect of RR pavements and façades, a new parameter, called equivalent albedo, is introduced and calculated over the canyon’s ceiling. The results show that a canyon with RR vertical surfaces and RR pavement reflects outward more radiation than a canyon with RR vertical surfaces and diffusive pavement due to the interaction of optical properties of the materials.
Data-driven prediction models of multi-dimensional energy consumed in public buildings
Authors: Yibo Chen , Umberto Berardi
Published: October 2019

Due to the intense pressure from energy shortage and environmental protection, an accurate prediction of building energy consumption is crucial for different energy conservation applications and policies. Besides simulation models and traditional statistical approaches, a data-driven modelling based on energy records provides new opportunities for predicting the building energy demand. This research is conducted based on the whole procedure of data mining with limited datasets, by making use of machine learning techniques and mathematical statistics. Especially, regarding the temporal and the architectural scales, models can be categorized into the short-term prediction, medium-term prediction and long-term prediction of classified energy consumptions, which also represent different modelling characteristics derived from mass data, limited data and poor data respectively. During the modelling process, the fuzzy C-means clustering and the interdisciplinary Lorenz curve were utilized to recognize different energy patterns. Afterwards, models of the nonlinear Support Vector Regression, the Grey model and the traditional polynomial regression were utilized respectively to output the predicted sequence. In summary, with datasets in current energy platforms, this paper presents a study of data-driven models based on energy records considering the nonlinear and uncertain features of different multi-dimensional models.
Simulation-supported shading design optimisation for a multi-storey building with passive cooling
Authors: Eikemeier S , Wimmer R , Mahdavi A
Published: October 2019

This contribution reports on an ongoing research effort to reduce the heating demand and overheating risk in the cold and warm seasons respectively. A simulation-supported optimisation strategy for life cycle oriented buildings was pursued, resulting also in improved ratings in terms of the concurrently calculated mandatory Austrian energy certificate. Thereby, a range of different building types was considered, including a multi-storey building that uses locally available ecological construction materials and renewable energy. Apart from the heating demand of the building, the indoor environment for selected living units was specifically examined to avoid overheating risk and to increase the thermal comfort for the occupants. To reduce the indoor temperatures for different thermal zones, the dimensions of external shading elements were investigated. Likewise, natural ventilation scenarios were explored to improve summer-time thermal comfort conditions. The results suggest that by using properly dimensioned external fixed shading devices, especially in combination with natural ventilation, the indoor temperatures and also the thermal comfort can be improved significantly, while maintaining the passive house standard according to the Austrian energy certificate.
Prediction of buildings’ cooling energy demand: A comparison of simulation-based and prescriptive approaches
Authors: Alhayek M , Wadi A , Pont U , Mahdavi A
Published: October 2019

Detailed simulation of buildings’ thermal performance can provide useful information for building designers and engineers. However, deployment of detailed simulation involves a number of challenges, including time and effort expenditures not accounted for in many typical building delivery processes. In this context, careful application of simplified methods may provide – at least for a specific class of applications – a reasonable alternative. The present contribution explores this possibility via a specific case study involving a large sample of residential buildings in Gaza, Palestine. This sample includes some fifty multi-unit apartment buildings representing the bulk of residential building stock in Gaza. These buildings were subjected to computational cooling energy demand assessment, whereby both numeric simulation and derivative simplified methods were applied. Numeric simulations were performed using EnergyPlus. For simplified calculations, a regression-based procedure was derived. Toward this end, a number of candidate independent variables (e.g., compactness, effective window-to-wall ration, LEK value, mean effective U-value) were considered and the level of their association with the computed values of the designated building performance indicators was observed. The comparison of the results of the simplified and simulation-based methods revealed a reasonable level of agreement. In other words, the application of the simplified method provides in the majority of the cases performance indicator values that are close enough to the corresponding results of the simulation-based method. This implies that simplified methods and associated prescriptive procedures may provide an attractive alternative to highly detailed simulation studies in cases were the paucity of information and/or computational resources may represent a challenge (e.g., early design stages, insufficient preparedness of the professional community, contextual constraints).
Heating demand and indoor air temperature prediction in a residential building using physical and statistical models: a comparative study
Authors: Sun Y , Joybari M M , Panchabikesan K , Moreau A , Robichaud M , Haghighat F
Published: October 2019

In Canada, space heating accounts for the largest proportion of energy consumption in residential buildings. Therefore, accurately predicting the heating demand and interior temperature of a residential building plays a vital role in estimating the building’s total energy consumption with the consideration of thermal comfort. The prediction results obtained through different models could be used to develop predictive controllers to achieve peak shifting as well as to provide utility providers with valuable information for electric power distribution. Common methods to predict heating demand mainly include physical models and statistical methods. This study used two physical models (i.e. TRNSYS model and TRNSYS-CONTAM model) and one statistical model using supervised machine learning algorithm to predict the heating demand as well as the indoor temperature of a residential building, located in Quebec, Canada. Results show that TRNSYS-CONTAM model has higher accuracy than TRNSYS model no matter in terms of interior air temperature or heating demand prediction, while the statistical model shows better interior air temperature prediction result than physical models.
Control method for adaptive façades based on energy conservation and glare protection strategies
Authors: Lee Dong-Seok , Ji Kyung-Hwan , Jo Jae-Hun
Published: October 2019

This study focuses on the control method of an adaptive façade based on the combination of energy conservation and glare protection strategies. Two evaluation methods are applied. The first method is to determine the appropriate range of the shading states which allow a minimum amount of solar heat gain and lighting energy requirements in the passive zone. The second method is to determine the appropriate range of the shading states which protect discomfort glare. Finally, the hourly optimal shading state can be determined through the two evaluation methods. In the application, the hourly shading state of a dynamic folding system, which can fully close and open in the two directions, is derived and evaluated. The results of the evaluation showed that the optimal control method suggested in this study can deliver effective energy performance while avoiding discomfort glare.
District household electricity consumption pattern analysis based on auto-encoder algorithm
Authors: Jin Yuan , Yan Da , Zhang Xingxing , Han Mengjie , Kang Xuyuan , An Jingjing , Sun Hongsan
Published: October 2019

The energy shortage is one key issue for sustainable development, a potential solution of which is the integration with the renewable energy resources. However, the temporal sequential characteristic of renewable resources is different from traditional power grid. For the entire power grid, it is essential to match the energy generation side with the energy consumption side, so the load characteristic at the energy use side is crucial for renewable power integration. Better understanding of energy consumption pattern in buildings contributes to matching different source of energy generation. Under the background of integration of traditional and renewable energy, this research focuses on analysis of different household electricity consumption patterns in an urban scale. The original data is from measurement of daily energy consumption with smart meter in households. To avoid the dimension explosion phenomenon, the auto-encoder algorithm is introduced during the clustering analysis of daily electricity use data, which plays the role of principal component analysis. The clustering based on auto-encoder gives a clear insight into the urban electricity use patterns in household. During the data analysis, several feature variables are proposed, which include peak value, valley value and average value. The distinction analysis is also conducted to evaluate the analysis performance. The study takes households in Nanjing city, China as a case study, to conduct the clustering analysis on electricity consumption of residential buildings. The analysis results can be further applied, such as during the capacity design of district energy storage.
Mitigation of rising urban temperatures starting from historic and modern street canyons towards zero energy settlement
Authors: Lassandro P , Di Turi S , Zaccaro S A
Published: October 2019

The necessity of restraining global warming to 1.5°C (IPCC Special Report 2018) implies many actions at global and local level in order to reduce CO2 emissions to net zero by 2050. Moreover, in urban area, the intensity of more and more frequent heatwaves is magnified by Urban Heat Island (UHI) effects and it increases the production of CO2 due to the intensification in cooling demand. Over the years, the historic settlement (medieval town) has showed to be more resilient to temperature changes than modern district. This paper compares the historic district with the modern one in Bari (southern Italy) in terms of morphology, type and construction technology through Envi-met simulations. It highlights how the fabric of the old town may have positive impact on summer regime for thermal comfort and its analysis can be useful for the definition of some guidelines for contemporary settlement. Natural solutions (e.g. vegetation, green roofs and water jects) and cool materials are proposed to reduce energy demand according to EU directive 2018/844 and complying with the constraints for consolidated urban area. The aim is also to evaluate the solutions for microclimate mitigation of urban canyons towards zero energy settlement starting from the old town features.
Analysis of monitoring data for a nZEB in Mediterranean climate
Authors: Ascione F , Borrelli M , De Masi R F , De Rossi F , Vanoli G P
Published: October 2019

The proposed paper is focused on some of the main conceptions, design criteria and expected energy performance of a new nZEB built in Benevento, a middle-size city of South Italy with typical Mediterranean climate. It is the result of an Italian research project – SMARTCASE – promoted under the umbrella of the European Regional Development Fund. The paper discusses the results of the wintertime monitoring campaign. Measurements on building envelope are shown as well as monitoring of energy uses and indoor microclimatic conditions. The discussion about the hourly energy balance evidences the effectiveness of selected solutions to reach the zero objective also during the winter and to evaluate the incidence of PV-production.
Roadmap Toward NZEBs in Quito
Authors: Ordoñez Elizabeth , Mora David , Gaudry Karl
Published: October 2019

Equatorial and Andean climate has no extreme temperatures; however, the region has a high diurnal oscillation. The government seeks to contribute to the improvement of housing conditions, which is mainly reflected in the emblematic housing program “Plan Casa para Todos” (PCT). PCT that aims to cover the social demand and reduce the qualitative housing deficit. It has been widely discussed that habitability and the housing deficit cannot be improved if the thermal conditions of dwellings and passive designed strategies are ignored, thus passive design principles, active devices, and renewable energy (RE) offer a way forward. Based on the hypothesis to bring out the possibility of reaching Net-Zero Energy Buildings (NZEB) in Quito, the objective is to develop a roadmap towards possible NZEBs. Inspired by genetic algorithms, optimization models were used to obtain the ideal NZEB for Quito. Simulations were carried using Python software with the calculating engine Energy Plus. First results show that the relationship towards the urban grid, the internal and spatial layout, thickness of walls, roof’s sealing, among other factors, significantly affect the energy-efficiency as well as the thermal comfort conditions. Further research is required from the science-policy interface to apply NZEBs effectively.
Static and dynamic thermal properties of construction components: A comparison in idealized and experimental conditions using lumped parameter models
Authors: Tronchin Lamberto , Manfren Massimiliano , Vodola Vincenzo , Bisegna Fabio , Nardecchia Fabio
Published: October 2019

The U values assumptions for construction components represent a significant source of uncertainty when estimating the energy performance of buildings. This uncertainty affects decision-making processes in multiple ways, from policy making to design of new and refurbished buildings. The correct estimation of both static (e.g. thermal transmittance) and dynamic thermal properties is crucial for quality assurance in building performance assessment. Further, while today many sophisticated simulators are available for building performance modelling, lumped parameter models can help reducing computational time for parametric simulation or optimization and enable inverse estimation of lumped thermal characteristics. A lumped parameter approach for construction components is proposed, for example, by the ISO 52016-1:2017 norm, introducing simplifications that are intrinsically dependent on component’s stratigraphy. This approach complements ISO 13786:2017 norm method, which is limited to steady-state periodic temperature and heat flux boundary conditions. In this research we consider these two different approaches, detailed and lumped modelling, comparing them first in idealized conditions and then in experimental conditions to analyse the robustness of methods.
Development of a multi criteria analysis method to optimize the sustainable architectural design of residential buildings.
Authors: Reuter I , Reiter S
Published: October 2019

This research is dedicated to the development of a multi criteria analysis method to optimize the sustainable architectural design of residential buildings. In this perspective, four axes have been chosen on the entire building life cycle: energy, ecology, health (including well-being) and economy. The building setting will be evaluated as its typology, its size, its construction method, the choice of the materials and of the systems implemented, since all these elements influence energy consumptions, environmental impacts, users’ health and financial costs. In order to be able to compare the four dimensions of this assessment, the developed methodology is based on the translation of energy consumption, environmental impacts and health impacts into energy costs, environmental costs and health costs, which makes them comparable to the building life cycle costs. According to users’ selection of the optimization axis and various optimization and design parameters, based on predefined options, this methodology will produce optimal solutions. Finally, this method will be useful for improving the sustainable performances of buildings, helping to create energy-efficient, ecological, healthy and affordable housing projects.
Assessing the annual power reliability of a residential building in relation to its ventilation system type: The case study of the off-grid container house in Shanghai.
Authors: Satola Daniel , Kristiansen Audun Bull , Dziedzic Jakub , Gustavsen Arild
Published: October 2019

In developing countries, electrification of rural and remote areas is an essential need for improving socio-economic conditions. However, increased access to adequate electricity and upgraded facilities may double or even triple present greenhouse gas emissions related to residential buildings operation. From both socio-economic and environmental perspective, implementation of solar-powered houses is widely considered as a sustainable. Power reliability is a key indicator used in assessing the annual performance of the off-grid housing operation. The primary objective of this article is to ascertain the impact of three main ventilation system types: natural (NV), mechanical with heat recovery (MV) and hybrid (HV) on annual power reliability of the case, off-grid building located in Shanghai. Firstly, three scenarios of hourly electricity loads profiles were calculated from an annual simulation via building performance software (BPS). Secondly, electrical load profiles were integrated into a developed model of alternating current (AC) coupled battery off-grid energy system model. The results indicate that the HV system provided the lowest annual electricity consumption (2847 kWh) and the best annual power reliability (98.6%) when compared to MV (2935kWh, 98.5%) and NV (2901kWh, 98.0%). The article discusses correlation between building ventilation scenarios, electrical loads and resultant annual power reliability. In conclusion economic viability of mechanical/hybrid ventilation implementation in off-grid housing is called into question.
Robust and resilient buildings: A framework for defining the protection against climate uncertainty
Authors: Moazami Amin , Carlucci Salvatore , Geving Stig
Published: October 2019

The design of high-performance buildings has been questioned for their actual performance in operation, where the impact of external perturbations such as occupant behavior and climate has proved to be prominent. These sources of variability, called aleatory uncertainties, are inherent variations of nondeterministic systems and are irreducible. Therefore, one of the main approaches to deal with these uncertainties is to consider them as noise during the design phase. The goal of the design is hence achieving a solution whose performance is least sensitive to the noise. This specific design process is called robust design. In this study, a prospect of climate conditions that a building might face during its lifespan is identified. However, although robust design can support the design of building variants whose performance is insensitive to typical climate conditions and also predictable extreme climate conditions, these building variants cannot be considered protected in case of unforeseeable extreme events. During such events, another property called resilience is required, which focuses on withstanding and recovering during and after the occurrence of the event. This study reviews the concepts of robustness and resilience and organizes them into a framework that clarifies their relationships in the protection of buildings against climate uncertainties.
BIM-BEM support tools for early stages of zero-energy building design
Authors: Spiridigliozzi Giulia , Pompei Laura , Cornaro Cristina , Santoli Livio De , Bisegna Fabio
Published: October 2019

Due to the Energy Performance of Building Directive 2010/31/UE (EPBD) recast, new and existing buildings have the aim to achieve the Zero Energy Buildings (ZEBs) requirements, in order to reduce the carbon emission and the energy building demand. Therefore, the building process cost is increasing, related to the applications of performant construction and efficiencies energy systems. In literature, several studies highlight the importance of innovative approaches in order to reduce the cost of the ZEB targets achievement, during the early stage design process. In this framework, Building Information Modeling (BIM) is a useful process that integrated building design since the first design stage, providing high-performance energy solutions and obtaining a single model reducing time and cost during the building design. In fact, in Italy, the regulatory obligations are progressively defined: with the Ministerial Decree 560 of 1 December 2017 (Baratono Decree), the time scale with which the obligation to use BIM will come into force has been established. The obligation started from 1 January 2019 for public tenders for an amount equal to or greater than 100 million euros, then there will be a gradual entry up to 2025 for public works contracts worth less than one million. The research proposes a new workflow that allows to performing energy analysis through the BIM and Building Energy Modeling (BEM) optimization interoperability, allowing to support the zero-energy building during the early stage design.
Towards a phylogenetic classification of the Ocotea complex (Lauraceae): an analysis with emphasis on the Old World taxa and description of the new genus Kuloa
Authors: Trofimov Dimitrij , Rohwer Jens G
Published: October 2019

Ocotea is one of the largest genera in the Lauraceae (c. 400 spp.), and it has been known to be paraphyletic with respect to most other genera of the New World Lauraceae for almost 20 years. In the traditional circumscription, Ocotea contains not only Neotropical species, but also about 45 species from the African region, including Macaronesia, Madagascar, and the Comoro and Mascarene Islands. Only a few of the species have been included in previous molecular systematic analyses. Here we present a phylogenetic analysis, based on ITS and psbA-trnH sequences of 168 Lauraceae species, including 151 taxa from the Ocotea complex, among them 26 of the 45 Palaeotropical species currently placed in Ocotea. Our results show that the Old World species belong to two well-supported and morphologically distinguishable clades, one of which is placed unresolved among the Neotropical clades of the Ocotea complex, whereas the other is sister to Cinnamomum section Cinnamomum. The two clades can also be differentiated based morphologically. As a step towards a phylogenetic classification, we recognize the second group as the new genus Kuloa.
Premovement Suppression of Corticospinal Excitability may be a Necessary Part of Movement Preparation
Authors: Ibáñez J , Hannah R , Rocchi L , Rothwell J C
Published: October 2019

In reaction time (RT) tasks corticospinal excitability (CSE) rises just prior to movement. This is preceded by a paradoxical reduction in CSE, when the time of the imperative (“GO”) stimulus is relatively predictable. Because RT tasks emphasise speed of response, it is impossible to distinguish whether reduced CSE reflects a mechanism for withholding prepared actions, or whether it is an inherent part of movement preparation. To address this question, we used transcranial magnetic stimulation (TMS) to estimate CSE changes preceding 1) RT movements; 2) movements synchronized with a predictable signal (predictive timing or PT movements); and 3) self-paced movements. Results show that CSE decreases with a similar temporal profile in all three cases, suggesting that it reflects a previously unrecognised state in the transition between rest and movement. Although TMS revealed reduced CSE in all movements, the TMS pulse itself had different effects on movement times. TMS given ~200 ms before the times to move speeded the onset of RT and self-paced movements, suggesting that their initiation depends on a form of trigger that can be conditioned by external events. On the contrary, PT movements did not show this effect, suggesting the use of a different triggering strategy prioritizing internal events.