The Effects of Physical Parameters of Buildings on Energy Consumption
Fatemeh Bateni*
*Department of Architecture and Urbanism Engineering,
Qazvin Islamic Azad University, Qazvin, Iran
Email:
fatemeh.bateni87@gmail.com
Abstract
Nowadays, over 40% of energy consumption in the world occurs in the
building sector. Given such a significant impact,
designing buildings with
long-term energy efficiency is of substantial importance. The purpose of
the present study is to assess the thermal performance of a vast
spectrum of parameters, including building orientation, window-to-wall
ratio, transparency, and geographical direction in a cold and temperate
climate. To this end, a case study is conducted on eight samples of
prevalent building plans in Ilam city, located in the west of Iran. The
results of the data analysis were written as mathematical functions, and
ultimately, the proposed pattern function related to the four selected
criteria of the optimal pattern was presented by comparing the functions
of thermal comfort and natural lighting. In conclusion,
square-shaped plans are the most
optimal, and higher length-to-width ratios lead to higher energy
consumption.
Keywords : Physical Parameters; Residential Buildings; Energy
Consumption; Square-shaped Plans; Building Designing
Introduction
In every country, the building sector is responsible for more than one
third of the total energy consumption (1). As a result, the amount and
methods of energy consumption in buildings have always been a concern in
construction projects. However, such a concern can be considerably
mitigated by using modern technologies and adhering to the existing
construction standards. In many countries, the shape and form of
buildings are chosen based on climate conditions, which in turn affect
how energy is consumed; in other words, the forms of buildings are
selected through strategies that are suitable to the climate
(1). Accordingly, the most
important related indices include the type of materials, building
orientation, thickness of walls, openings, and type of ceiling (2, 3).
Attention has been paid to these indices, and today, architects also
take them into account when reviewing the rules and changes to optimize
energy consumption and lessen the consequences of unregulated
consumption.
The direct or indirect consumption of fossil fuels in buildings emits a
large amount of CO2 into the atmosphere. Contemplating and recognizing
the means to reduce CO2 production and consume energy in an optimal
manner are instrumental to confronting the incorrect use of energy
(4-6). This amount of emission amounts to nearly 40% of the entire CO2
(i.e., 842 million tonnes per year) (7), which entails 36% of the
global energy consumption (8-10). Today, energy saving refers to the
implementation of solutions specified under various regulatory
frameworks (11, 12). Global guidelines on the energy performance of
buildings require the adoption of tools for calculating energy
consumption performance, applying the minimum performance standards
during the design process, operating the construction, licensing the
building, and ensuring control over heating and cooling systems (13-15).
In fact, interior thermal comfort is considered the main driver of
energy consumption in buildings (11, 16, 17), which can be of importance
in two areas, including the type of consumed and the physical factors
involved in energy consumption and suitable efficiency.
Due to the inevitable degradation in their physical performance, many of
the existing buildings are unlikely to be regarded as “green”
buildings in terms of energy consumption. The physical performance of
buildings should be specified in detail prior to any construction or
system maintenance operations (18-20). There are numerous studies
conducted on areas such as consumer behaviour, construction operation
and system repair and maintenance, envelope function, lighting, hot
water and heating systems, building materials, and HVAC (heating,
ventilation, and air conditioning); these studies have offered a variety
of models on energy reinforcement strategies and economic assessment of
different types of existing structures in residential and
non-residential buildings (21, 22).
In Europe, the AR ranking, which assesses the physical performance of
buildings, is used to enhance the energy performance of degraded
buildings. This method provides reliable information regarding how
energy is consumed or wasted in these types of buildings, with the
ultimate purpose of reducing energy consumption and specifying the
effect of each physical dimension on the amount of energy consumption.
Nonetheless, collecting consistent data on the existing buildings is
difficult, and the energy performance assessment of these buildings is
commonly done using simplified data obtained from refined data and
tables from different sources (23, 24). The same approach is adopted in
this study.
Numerous studies conducted in this area have examined optimal building
designs; therefore, many more passive solutions have been proposed
regarding energy reduction and efficiency in the building sector.
Studies have shown that the energy performance of buildings depends on
five factors, including weather, building design, urban geometry, system
efficiency, and residents’ behaviour (25). According to evidence, the
architectural design helps to reduce energy consumption (26, 27). In
design and construction principles, inactive design strategies and
bioclimatic designs are the main solutions to minimize energy demand
(28). Studies have classified building designs into six parameters,
which include the shape of the building, transparent surfaces,
orientation of the building, thermal-physical features, building
materials, and distances between buildings (29, 30).Clearly, energy
source provision is one of the future concerns of mankind. The essential
actions to mitigate these concerns may include controlling energy
consumption, using clean energies, and employing modern knowledge for
constructions with minimum energy consumption (31).
In the present study, the design and construction of buildings in cold,
temperate, and Mediterranean climates are highlighted. The empirical
designing and constructing of buildings via different materials has, in
many cases, offered substantially suitable potentials to create
buildings that consistently involve optimal energy consumption. These
indices have been mostly related to available materials, consistency
between the climate and buildings, and the method of using renewable
energies through building architecture, acquired through experiment over
time. Given changes in lifestyle, fuel diversity, economic costs, family
behaviour, available materials, and climate change, it appears that
previous methods cannot meet the requirements of optimal energy
consumption. Given such a fact, it is necessary to employ the technology
of today’s world to optimize these indices and make use of new energy
consumption methods in buildings. All in all, reducing energy
consumption in buildings requires accurate, practical answers to the
issue. As a result, the present study seeks to examine the effect of
buildings’ physical features on the extent of energy consumption;
further, different types of buildings and prevalent architectures in
this study were compared to calculate energy consumption in various
forms and provide suitable strategies for optimizing energy consumption
in these buildings.
Materials and Methods
The present research is an applied, design-based study conducted using
the analytical approach. The purpose of the study was to evaluate the
physical parameters of residential buildings with the prevalent edge
ratios in Ilam City – located in Iran – in order to provide an optimal
pattern relative to the assessed parameters. Accordingly, eight
prevalent residential building plans with the same total area (156
m2) were taken into account (Samples A, B, C, D, E, F,
G, and H).
Generally, the A/C and lighting systems in a residential building
account for 40% and 11% of the total energy consumption, respectively.
The eight samples in this study were examined in terms of thermal
performance and lighting of the entire building. The physical
characteristics of buildings, such as materials and the type of
openings, were considered the same across all eight samples in the data
analysis. Materials used in this study are as follows: