Abstract: Renewable energy resources, which can supplement space and water heating for residential buildings, can have a noticeable impact on natural gas consumption and air pollution. This study considers a technical analysis of a combined solar water heating system with evacuated tube solar collectors for different solar coverage, ranging from 20% to 100% of the total roof area of a typical residential building located in Edmonton, Alberta, Canada. The alternative heating systems were conventional (non-condensing) and condensing tankless water heaters and condensing boilers that were coupled to solar water heating systems. The performance of the alternative heating systems was compared to a traditional heating system, consisting of a conventional boiler, applied to houses of various gross floor areas. A comparison among the annual natural gas consumption, carbon dioxide (CO2) mitigation, and emissions for the various house sizes indicated that the combined solar heating system can reduce the natural gas consumption and CO2 emissions, and increase CO2 mitigation for all the systems that were studied. The results suggest that solar water heating systems are potentially beneficial for residential heating system applications in terms of energy savings and CO2 mitigation.
Abstract: Reinforced concrete (RC) shear wall system of residential buildings is popular in South Korea. RC walls are subjected to axial forces in common and the effect of axial forces on the strength loss of the fire damaged walls has not been investigated. This paper aims at investigating temperature distribution on fire damaged concrete walls having different axial loads. In the experiments, a variable of specimens is axial force ratio. RC walls are fabricated with 150mm of wall thicknesses, 750mm of lengths and 1,300mm of heights having concrete strength of 24MPa. After curing, specimens are heated on one surface with ISO-834 standard time-temperature curve for 2 hours and temperature distributions during the test are measured using thermocouples inside the walls. The experimental results show that the temperature of the RC walls exposed to fire increases as axial force ratio increases. To verify the experiments, finite element (FE) models are generated for coupled temperature-structure analyses. The analytical results of thermal behaviors are in good agreement with the experimental results. The predicted displacement of the walls decreases when the axial force increases.
Abstract: Average temperatures worldwide are expected to
continue to rise. At the same time, major cities in developing
countries are becoming increasingly populated and polluted.
Governments are tasked with the problem of overheating and air
quality in residential buildings. This paper presents the development
of a model, which is able to estimate the occupant exposure
to extreme temperatures and high air pollution within domestic
buildings. Building physics simulations were performed using the
EnergyPlus building physics software. An accurate metamodel is
then formed by randomly sampling building input parameters and
training on the outputs of EnergyPlus simulations. Metamodels are
used to vastly reduce the amount of computation time required when
performing optimisation and sensitivity analyses. Neural Networks
(NNs) have been compared to a Radial Basis Function (RBF)
algorithm when forming a metamodel. These techniques were
implemented using the PyBrain and scikit-learn python libraries,
respectively. NNs are shown to perform around 15% better than RBFs
when estimating overheating and air pollution metrics modelled by
EnergyPlus.
Abstract: In this study, electric field distribution analyses for
three pylon models are carried out by a Finite Element Method
(FEM) based software. Analyses are performed in both stationary and
time domains to observe instantaneous values along with the
effective ones. Considering the results of the study, different line
geometries is considerably affecting the magnitude and distribution
of electric field although the line voltages are the same. Furthermore,
it is observed that maximum values of instantaneous electric field
obtained in time domain analysis are quite higher than the effective
ones in stationary mode. In consequence, electric field distribution
analyses should be individually made for each different line model
and the limit exposure values or distances to residential buildings
should be defined according to the results obtained.
Abstract: Residential buildings consume significant amounts of
energy and produce large amount of emissions and waste. However,
there is a substantial potential for energy savings in this sector which
needs to be evaluated over the life cycle of residential buildings. Life
Cycle Assessment (LCA) methodology has been employed to study
the primary energy uses and associated environmental impacts of
different phases (i.e., product, construction, use, end of life, and
beyond building life) for residential buildings. Four different
alternatives of residential buildings in Vancouver (BC, Canada) with
a 50-year lifespan have been evaluated, including High Rise
Apartment (HRA), Low Rise Apartment (LRA), Single family
Attached House (SAH), and Single family Detached House (SDH).
Life cycle performance of the buildings is evaluated for embodied
energy, embodied environmental impacts, operational energy,
operational environmental impacts, total life-cycle energy, and total
life cycle environmental impacts. Estimation of operational energy
and LCA are performed using DesignBuilder software and Athena
Impact estimator software respectively.
The study results revealed that over the life span of the buildings,
the relationship between the energy use and the environmental
impacts are identical. LRA is found to be the best alternative in terms
of embodied energy use and embodied environmental impacts; while,
HRA showed the best life-cycle performance in terms of minimum
energy use and environmental impacts. Sensitivity analysis has also
been carried out to study the influence of building service lifespan
over 50, 75, and 100 years on the relative significance of embodied
energy and total life cycle energy. The life-cycle energy requirements
for SDH are found to be a significant component among the four
types of residential buildings. The overall disclose that the primary
operations of these buildings accounts for 90% of the total life cycle
energy which far outweighs minor differences in embodied effects
between the buildings.
Abstract: Based on an indoor environmental quality (IEQ) index established by previous work that indicates the overall IEQ acceptance from the prospect of an occupant in residential buildings in terms of four IEQ factors - thermal comfort, indoor air quality, visual and aural comforts, this study develops a user-friendly IEQ calculator for iOS and Android users to calculate the occupant acceptance and compare the relative performance of IEQ in apartments. “IEQ calculator” is easy to use and it preliminarily illustrates the overall indoor environmental quality on the spot. Users simply input indoor parameters such as temperature, number of people and windows are opened or closed for the mobile application to calculate the scores in four areas: the comforts of temperature, brightness, noise and indoor air quality. The calculator allows the prediction of the best IEQ scenario on a quantitative scale. Any indoor environments under the specific IEQ conditions can be benchmarked against the predicted IEQ acceptance range. This calculator can also suggest how to achieve the best IEQ acceptance among a group of residents.
Abstract: Thin-walled elements with a matrix set on a base of
high-valuable Portland cement with dispersed reinforcement from
alkali-resistant glass fibres are used in a range of applications as
claddings of buildings and infrastructure constructions as well as
various architectural elements of residential buildings.
Even though their elementary thickness and therefore total weight
is quite low, architects and building companies demand on even
further decreasing of the bulk density of these fibre-cement elements
for the reason of loading elimination of connected superstructures
and easier assembling in demand conditions.
By the means of various kinds of light-weight aggregates it is
possible to achieve light-weighing of these composite elements.
From the range of possible fillers with different material properties
granulated expanded glass worked the best.
By the means of laboratory testing an effect of two fillers based on
expanded glass on the fibre reinforced cement composite was
verified.
Practical applicability was tested in the production of commonly
manufactured glass fibre reinforced concrete elements, such as
channels for electrical cable deposition, products for urban equipment
and especially various cladding elements.
Even though these are not structural elements, it is necessary to
evaluate also strength characteristics and resistance to environment
for their durability in certain applications.
Abstract: In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.
Abstract: The concern with sustainability brought the need for optimization of the buildings to reduce consumption of natural resources. Almost 1/3 of energy demanded by Brazilian housings is used to provide thermal solutions. AEC sector may contribute applying bioclimatic strategies on building design. The aim of this research is to investigate the viability of applying some alternative solutions in residential buildings. The research was developed with computational simulation on single family social housing, examining envelope type, absorptance, and insolation. The analysis of the thermal performance applied both Brazilian standard NBR 15575 and degree-hour method, in the scenery of Porto Alegre, a southern Brazilian city. We used BIM modeling through Revit/Autodesk and used Energy Plus to thermal simulation. The payback of the investment was calculated comparing energy savings and building costs, in a period of 50 years. The results shown that with the increment of envelope’s insulation there is thermal comfort improvement and energy economy, with a pay-back period of 24 to 36 years, in some cases.
Abstract: In this study, we discussed the effects on the thermal
comfort of super high-rise residences that how effected by the high
thermal capacity structural components. We considered different
building orientations, structures, and insulation methods. We used the
dynamic simulation software THERB (simulation of the thermal
environment of residential buildings). It can estimate the temperature,
humidity, sensible temperature, and heating/cooling load for multiple
buildings. In the past studies, we examined the impact of
air-conditioning loads (hereinafter referred to as AC loads) on the
interior structural parts and the AC-usage patterns of super-high-rise
residences.
Super-high-rise residences have more structural components such
as pillars and beams than do ordinary apartment buildings. The
skeleton is generally made of concrete and steel, which have high
thermal-storage capacities. The thermal-storage capacity of
super-high-rise residences is considered to have a larger impact on the
AC load and thermal comfort than that of ordinary residences.
We show that the AC load of super-high-rise units would be
reduced by installing insulation on the surfaces of interior walls that
are not usually insulated in Japan.
Abstract: Energy consumption is a very important topic these
days especially regarding air conditioning in residential buildings,
since this takes the biggest amount of energy in buildings total
consumption, residential buildings constitute the biggest percentage
of energy consumption in Bahrain.
This research reflects on the effects of shading percentage in
different solar orientations on the energy consumption inside
residential buildings (domestic dwellings).
The research as found that, there are different effects of shading in
changing building orientation:
• 0.69% for the shading percentage 25% when the building is
oriented to the north (0º);
• 18.59% for 75% of shading in north-west orientation
(325º);
• The best effect for shading is in north-west orientation
(315º);
• The less effect for shading was in case of the building
orientation is the north (0º).
Abstract: There-s a lack in understanding the indoor climate of Malaysian residential. The assumption of traditional house could
provide the best indoor environment is too good to be true. This research is to understand indoor environment in three types of
Malaysian residential and thermo recorder TR72Ui were placed in
indoor spaces for measurement. There are huge differences of indoor
environment between housing types, and building material helps to control indoor climate. Traditional house indoor climate was similar to
the outdoor. Temperature in the bedroom of terrace and town houses were slightly higher than the living room. Indoor temperature was 2oC
lower in the rainy season than the hot season. It was hard to control
indoor humidity level in traditional house compared with terrace and
town house. As for conclusion, town house provides the best thermal
environment to the building occupants and can be improved with good
roof insulation.
Abstract: GFRG(Glass Fiber Reinforced Gypsum) wall is a green product which can erect a building fast in prefabricated method, but its application to high-rise residential buildings is limited for its poor lateral stiffness. This paper has proposed a modification to GFRG walls structure to increase its lateral stiffness, which aiming to erect small high-rise residential buildings as load-bearing walls. The elastic finite element analysis to it has shown the lateral deformation feature and the distributions of the axial force and the shear force. The analysis results show that the new GFRG reinforced concrete wall can be used for small high-rise residential buildings.
Abstract: Solar shading designs are important for reduction of building energy consumption and improvement of indoor thermal environment. This paper carried out a number of building simulations for evaluation of the energy performance of different shading devices based on incremental costs. The results show that movable shading devices lower incremental costs by up to 50% compared with fixed ones for the same building energy efficiency for residential buildings, and wing panel shadings are much more suitable in commercial buildings than baring screen ones and overhangs for commercial buildings.
Abstract: The increasing demand for sufficient and clean
energy forces industrial and service companies to align their strategies towards efficient consumption. This trend refers also to the
residential building sector. There, large amounts of energy consumption are caused by house and facility heating. Many of the
operated hot water heating systems lack hydraulic balanced working
conditions for heat distribution and –transmission and lead to
inefficient heating. Through hydraulic balancing of heating systems,
significant energy savings for primary and secondary energy can be
achieved. This paper addresses the use of KNX-technology (Smart
Buildings) in residential buildings to ensure a dynamic adaption of
hydraulic system's performance, in order to increase the heating
system's efficiency. In this paper, the procedure of heating system
segmentation into hydraulically independent units (meshes) is
presented. Within these meshes, the heating valve are addressed and
controlled by a central facility server. Feasibility criteria towards
such drivers will be named. The dynamic hydraulic balance is
achieved by positioning these valves according to heating loads, that
are generated from the temperature settings in the corresponding
rooms. The energetic advantages of single room heating control
procedures, based on the application FacilityManager, is presented.
Abstract: The building sector is the largest energy consumer and
CO2 emitter in the European Union (EU) and therefore the active
reduction of energy consumption and elimination of energy wastage
are among the main goals in it. Healthy housing and energy
efficiency are affected by many factors which set challenges to
monitoring, control and research of indoor air quality (IAQ) and
energy consumption, especially in old buildings. These challenges
include measurement and equipment costs, for example.
Additionally, the measurement results are difficult to interpret and
their usage in the ventilation control is also limited when taking into
account the energy efficiency of housing at the same time. The main
goal of this study is to develop a cost-effective building monitoring
and control system especially for old buildings. The starting point or
keyword of the development process is a wireless system; otherwise
the installation costs become too high. As the main result, this paper
describes an idea of a wireless building monitoring and control
system. The first prototype of the system has been installed in 10
residential buildings and in 10 school buildings located in the City of
Kuopio, Finland.
Abstract: Explosions may cause intensive damage to buildings
and sometimes lead to total and progressive destruction. Pressures
induced by explosions are one of the most destructive loads a
structure may experience. While designing structures for great
explosions may be expensive and impractical, engineers are looking
for methods for preventing destructions resulted from explosions. A
favorable structural system is a system which does not disrupt totally
due to local explosion, since such structures sustain less loss in
comparison with structural ones which really bear the load and
suddenly disrupt. Designing and establishing vital and necessary
installations in a way that it is resistant against direct hit of bomb and
rocket is not practical, economical, or expedient in many cases,
because the cost of construction and installation with such
specifications is several times more than the total cost of the related
equipment.
Abstract: Certifications such as the Passive House Standard aim to reduce the final space heating energy demand of residential buildings. Space conditioning, notably heating, is responsible for nearly 70% of final residential energy consumption in Europe. There is therefore significant scope for the reduction of energy consumption through improvements to the energy efficiency of residential buildings. However, these certifications totally overlook the energy embodied in the building materials used to achieve this greater operational energy efficiency. The large amount of insulation and the triple-glazed high efficiency windows require a significant amount of energy to manufacture. While some previous studies have assessed the life cycle energy demand of passive houses, including their embodied energy, these rely on incomplete assessment techniques which greatly underestimate embodied energy and can lead to misleading conclusions. This paper analyses the embodied and operational energy demands of a case study passive house using a comprehensive hybrid analysis technique to quantify embodied energy. Results show that the embodied energy is much more significant than previously thought. Also, compared to a standard house with the same geometry, structure, finishes and number of people, a passive house can use more energy over 80 years, mainly due to the additional materials required. Current building energy efficiency certifications should widen their system boundaries to include embodied energy in order to reduce the life cycle energy demand of residential buildings.
Abstract: This study was investigated on sampling and
analyzing water quality in water reservoir & water tower installed in
two kind of residential buildings and school facilities. Data of water
quality was collected for correlation analysis with frequency of
sanitization of water reservoir through questioning managers of
building about the inspection charts recorded on equipment for water
reservoir. Statistical software packages (SPSS) were applied to the
data of two groups (cleaning frequency and water quality) for
regression analysis to determine the optimal cleaning frequency of
sanitization. The correlation coefficient (R) in this paper represented
the degree of correlation, with values of R ranging from +1 to -1.After
investigating three categories of drinking water users; this study found
that the frequency of sanitization of water reservoir significantly
influenced the water quality of drinking water. A higher frequency of
sanitization (more than four times per 1 year) implied a higher quality
of drinking water. Results indicated that sanitizing water reservoir &
water tower should at least twice annually for achieving the aim of
safety of drinking water.
Abstract: In this paper a polymer electrolyte membrane (PEM)
fuel cell power system including burner, steam reformer, heat
exchanger and water heater has been considered to meet the
electrical, heating, cooling and domestic hot water loads of
residential building which in Tehran. The system uses natural gas as
fuel and works in CHP mode. Design and operating conditions of a
PEM fuel cell system is considered in this study. The energy
requirements of residential building and the number of fuel cell
stacks to meet them have been estimated. The method involved
exergy analysis and entropy generation thorough the months of the
year. Results show that all the energy needs of the building can be
met with 12 fuel cell stacks at a nominal capacity of 8.5 kW. Exergy
analysis of the CHP system shows that the increase in the ambient air
temperature from 1oC to 40oC, will have an increase of entropy
generation by 5.73%.Maximum entropy generates for 15 hour in 15th
of June and 15th of July is estimated to amount at 12624 (kW/K).
Entropy generation of this system through a year is estimated to
amount to 1004.54 GJ/k.year.