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Energy consumption and air-conditioning usage in residential buildings of Malaysia

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... Malaysian residential sector final energy consumption is divided into five aggregated categories; appliances, cooking, space cooling, lighting and water heating [6]. Meanwhile, typical terrace household energy use is segregated into cooking (45%), cooling (29%), others (11%), lighting (8%) and laundry/cleaning (7%) [7]. Under the cooling category, 17% is used up for air conditioning, 10% for ceiling fan and 2% for other types of cooling devices. ...
... In 2016, Berkeley National Lab reported that global AC installation will reach 700 million by 2030 and 1.6 billion by 2050. Accordingly, several local studies on the terrace house dwellers revealed more than half of the survey respondents owns AC unit, with at least two units installed in each households [7,18]. These indicators show AC will remain significant and more may be installed in the future. ...
... Malaysian residential electricity end use can be categorised by refrigeration (21.1%), cooking equipment (14.7%), air-conditioning (11.9%), washing machines (10.5%), illumination (5.1%) and others (36.7%) [19]. A typical monthly terrace house electricity consumption were 455kWh [7]. Under TNB's revised domestic tariff (Tariff A) [20], consumers pay RM 0.218/kWh for the first 200kWh (1kWh-200kWh), RM 0.334/kWh for the next 100 kWh (201kWh-300kWh), followed by a substantially higher rate of RM 0.516/kWh (301kWh-600kWh), RM 0.546 (601-900kWh) and RM 0.571 for the subsequent kWh used. ...
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Accounting for the government’s intention towards sustainable energy development and the deployment of Malaysia’s first smart grid system, inclusive participation of residential units will transform their role from consumers to prosumers, enabling them to become “positive nodes” of the smart grid system. This paper evaluates the simulation output of a grid displaced electricity demand of a significant terrace-based housing cohort in Malaysia. Utilising Integrated Environmental Solution Virtual Environment (IESVE) as the simulation tool, solar panel retrofitted to the existing terrace houses in urban centres across peninsular Malaysia is investigated in order to identify its potential to displace current grid electricity demand, consequently shaving peak demand and reduced household’s ‘s electricity bill.
... Adoption of climate sensitive building (CSB) design, that is designed for local climates, can improve indoor thermal comfort and limit the demand for AC usage. In Malaysia, residential AC usage is heavily weighted toward the evening [24], making night-time thermal comfort an important element of CSB design in this context. Indeed, indoor temperatures in Malaysian residences are much warmer at night than ambient temperatures [25], making residential CSB design may be a potential leverage point for altering AC usage. ...
... Night-time indoor temperatures are an important factor for AC usage in Malaysian residences. Indeed, a survey in Johor Bahru shows that AC usage is heavily weighted toward evening/night hours, peaking at 11 p.m. (80% of AC owners using AC), while day-time use is much lower (10% of AC owners using AC), even though 70% of residences are occupied during the day [24]. Most Malaysians do not use window ventilation at night, resulting in indoor temperatures being 4 °C warmer than outdoor ambient temperatures (Increased Temperature in CIB); this gap is reduced to 2.5 °C with window ventilation and to 0.5 °C when effective mechanical ventilation is also employed [25]. ...
... Night-time indoor temperatures are an important factor for AC usage in Malaysian residences. Indeed, a survey in Johor Bahru shows that AC usage is heavily weighted toward evening/night hours, peaking at 11 p.m. (80% of AC owners using AC), while day-time use is much lower (10% of AC owners using AC), even though 70% of residences are occupied during the day [24]. Most Malaysians do not use window ventilation at night, resulting in indoor temperatures being 4 • C warmer than outdoor ambient temperatures (Increased Temperature in CIB); this gap is reduced to 2.5 • C with window ventilation and to 0.5 • C when effective mechanical ventilation is also employed [25]. ...
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Dependence on air-conditioning (AC) for residential cooling and ventilation is a health and sustainability challenge. In hot temperatures, climate-sensitive buildings (CSB) can complement and/or substitute for AC usage in achieving thermal comfort. Many countries facing such conditions-particularly in tropical climates-are developing quickly, with rising populations and income creating demand for new housing and AC. This presents a window for adoption of CSB but could also result in long term lock-in of AC-dependent buildings. Here, a simple system dynamics model is used to explore the potential and limitations of subsidies to affect futures of housing stock and night-time AC usage in Malaysia. The effectiveness of subsidies in achieving high uptake of CSB and resulting health benefits is highly dependent on homebuyer willingness to pay (WTP). A detailed understanding of WTP in the Malaysian context and factors that can shift WTP is necessary to determine if CSB subsidies can be a good policy mechanism for achieving CSB uptake.
... In Southeast Asia, apart from Singapore, national surveys of energy use in households have hardly ever been conducted at national level. However, there are a number of studies at city or regional scale with sample sizes ranging from 100 to 10 0 0 households such as in Indonesia [7] , Malaysia [8] and Thailand [9] . ...
... This method has been widely used in many studies [8,[14][15][16][17][18] . The number of appliances and the frequency of use were the average values from the survey. ...
... Fig. 17 shows the comparison between several cities and countries in terms of household energy consumption by types of end use. The data were synthesised from various sources and studies [4,7,8,25,26] . Data on lighting and water heater consumption of Ho Chi Minh city were not available, they were therefore combined into other end-use categories. ...
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The domestic sector is responsible for approximately a third of total energy consumption in Vietnam. However, research on the details of energy consumption in this sector is relatively poor and there is a lack of data on actual energy use in households. This study attempts to fill the gap by providing an analysis of appliance penetration, usage behavior, and actual energy consumption of Vietnamese homes. Data were collected from a survey of 60 households in Tuy Hoa City on the South-Central Coast of Vietnam in 2017. The result shows that the average energy consumption was 4492 kWh per household per year, in which electricity and liquefied petroleum gas accounted for 74.4% and 25.6% respectively. The breakdown of current energy consumption revealed that cooling was the primary consuming end-use with 31.9% of the total, followed by cooking gas with 25.6% and kitchen appliances with 18.5%. Energy consumption for typical households with various ownership levels of air conditioner were also predicted. The results of this study are therefore a valuable reference for policy makers, energy planners and Vietnamese households themselves to understand the existing energy consumption characteristics and identify potential ways to improve energy efficiency in dwellings.
... For instance, in some cities, air-conditioning requirements take the full capacity of electricity grids [3,6]. According to Toe and Kubota [7], final energy use in residential and commercial sectors in Malaysia increased more than sevenfold between 1980 and 2007, at a higher rate than the total amount of energy-demand growth rate, based on the Ministry of Energy, Green Technology, and Water National Energy Balance 2007 report. In residential buildings, a large portion of electricity consumption was attributed to air-conditioning systems, as the ownership of air-conditioners expanded from approximately 12,000 to 764,000 households from the 1970s to the 2000s [7,8]. ...
... According to Toe and Kubota [7], final energy use in residential and commercial sectors in Malaysia increased more than sevenfold between 1980 and 2007, at a higher rate than the total amount of energy-demand growth rate, based on the Ministry of Energy, Green Technology, and Water National Energy Balance 2007 report. In residential buildings, a large portion of electricity consumption was attributed to air-conditioning systems, as the ownership of air-conditioners expanded from approximately 12,000 to 764,000 households from the 1970s to the 2000s [7,8]. ...
... Mohit and Mahfoud [36], via a survey, found out that especially double-story terraced houses could not satisfy occupants' needs for thermal and natural lighting comfort. Thus, most of the occupants opt for mechanical ventilation systems to solve the ventilation problem [7]. Meanwhile, based on Nugroho study [18], preliminary study using a field measurement on thermal comfort in a single-story terraced house in the context of Malaysia, it is revealed that the design of the single-story house in Malaysia is insufficient and not effective in providing thermal comfort through natural ventilation. ...
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The provision requirement of 10% openings of the total floor area stated in the Uniform Building By-Law 1984 Malaysia is essential for natural lighting and ventilation purposes. However, focusing on natural ventilation, the effectiveness of thermal performance in landed residential buildings has never been empirically measured and proven, as most of the research emphasized simulation modeling lacking sufficient empirical validation. Therefore, this paper drawing on field measurement investigates natural ventilation performance in terraced housing with an air-well system. The key concern as to what extent the current air-well system serving as a ventilator is effective to provide better thermal performance is to be addressed. By adopting an existing single-story air-welled terrace house, indoor environmental conditions and thermal performance were monitored and measured using HOBO U12 air temperature and humidity, the HOBO U12 anemometer, and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter for a six-month duration. The results show that the air temperature of the air well ranged from 27.48 °C to 30.92 °C, with a mean relative humidity of 72.67% to 79.25%. The mean air temperature for a test room (single-sided ventilation room) ranged from 28.04 °C to 30.92 °C, with a relative humidity of 70.16% to 76.00%. These empirical findings are of importance, offering novel policy insights and suggestions. Since the minimum provision of 10% openings has been revealed to be less effective to provide desirable thermal performance and comfort, mandatory compliance with and the necessity of the bylaw requirement should be revisited.
... Pal et al. [30] also proved that the occupant behaviour in using heating appliances affected the energy consumption from an office in France. In contrast, Kubota et al. [19] conducted a survey with 338 respondents on Sustainability 2021, 13, 818 4 of 31 terrace houses in Malaysia and found that occupants did not consider outdoor temperatures while using air conditioning appliances. This was because Malaysia has hot and humid weather conditions regularly and outdoor temperatures remain almost constant throughout the year. ...
... Jaffar et al. [28] studied energy demand for residential buildings in Kuwait using 250 households and they found that most occupants set the temperature of air conditioning between 20 • C and 22 • C. In other studies, Kubota et al. [19] reported that occupants in Malaysia set the temperature between 20 • C and 21 • C based on a survey from 213 respondents. Hisham et al. [32] who performed field measurements on 19 dwellings consisting of low-cost apartments and one terraced house in Malaysia, found that the temperature setting of air conditioning ranged from 16 • C to 28 • C. ...
... Kim [5] discovered that the average operating time for air conditioners was 0.32 h/day in 2250 households in Korea. In contrast, Kubota et al. [19] found that the average operating times for air conditioning appliances in Malaysia was 6 h/day. Zaki et al. [33] studied 38 dwellings in Kuala Lumpur and found that the average operating times of air conditioning appliances mostly ranged from 1 h/day to 6 h/day. ...
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Electricity-saving strategies are an essential solution to overcoming increasing global CO2 emission and electricity consumption problems; therefore, the determinant factors of electricity consumption in households need to be assessed. Most previous studies were conducted in developed countries of subtropical regions that had different household characteristic factors from those in developing countries of tropical regions. A field survey was conducted on electricity consumption for Malaysian households to investigate the factors affecting electricity consumption that focused on technology perspective (building and appliance characteristics) and socio-economic perspective (socio-demographics and occupant behaviour). To analyse the determinant factors of electricity consumption, direct and indirect questionnaire surveys were conducted from November 2017 to January 2018 among 214 university students. Direct questionnaire surveys were performed in order to obtain general information that is easily answered by respondents. On the other hand, some questions such as electricity consumption and detailed information of appliances must be confirmed by the respondents’ parents or other household members through an indirect questionnaire survey. The results from multiple linear regression analyses of the survey responses showed that appliance characteristic factors were the main variables influencing electricity consumption and house characteristics were the least significant. Specifically, air conditioners, fluorescent lamps, and flat-screen TVs emerged as appliances with the most significant effect on electricity consumption. Occupant behaviour factors had a more significant influence than socio-demographic factors. The findings in this study can be used by policymakers to develop electricity-saving strategies in Malaysia.
... Thus, more than a fifth of the energy demand were for cooling purpose signifying a large scope for building's thermal performance improvement, implementation strategies utilising innovative technologies for higher efficiency and clean energy generation. Another study by Toe (2013) and Kubota et al. (2011) found that AC ownership have increased among Malaysian households, where AC owners consume 1.4 more energy than the average terrace house resident population. Thus, typical electricity generation from power plants operating on coal and gas can be reduced, especially during critical peak load demand, leading to a positive impact on the Malaysian electricity sector. ...
... The higher household incomes were attributed by these factors; two persons were earning for the household, a majority of the respondents were middle class society and employment in urban areas paid relatively higher. As such, larger income signifies better purchasing power, driving aspiration for better living standard, as implied by other similar studies (Toe, 2013; Kubota et al., 2011;Isa et al., 2010). Furthermore, a study by Kubota et al. (2011) discovered a direct relationship between high income and AC ownership. ...
... As such, larger income signifies better purchasing power, driving aspiration for better living standard, as implied by other similar studies (Toe, 2013; Kubota et al., 2011;Isa et al., 2010). Furthermore, a study by Kubota et al. (2011) discovered a direct relationship between high income and AC ownership. Thus, the change in spending contributed to the shift in consumption pattern that drove expansion in energy demand within this sector. ...
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Increasing demand for energy and associated issues of the traditional grid entail Malaysia (spearheaded by Tenaga Nasional Berhad-Malaysia’s leading utility) to pursue a smart grid transformation plan. Indeed, the smart grid is perceived as an attractive solution due to its reliable, secure and sustainable electricity delivery system. As the energy demand of the residential sector is a fifth of the national energy consumption in Malaysia, the performance of present and future houses will have a significant impact on electricity grid support requirements. As such, investigating existing energy consumption profile and its housing typology is indispensable to appraise Malaysian smart grid development through the identification of energy generation potentials and usage profile of its domestic consumers. An engaged study has identified a significant scope for improvements to the current and future housing stock, by reducing energy demand for cooling while increasing indoor comfort levels. This paper analyses the current state of the Malaysian terrace houses, the most common residential type in the country, using results of the first nationwide energy consumption survey on samples across peninsular Malaysia. As the terrace house type – expression of the growing middle class - makes up around forty per cent of the national housing stock, any improvement of its performance will have significant impact on national energy strategies. Data acquired from the survey will be used to develop a base case simulation model of the selected house type. Dynamic thermal simulation via Integrated Environmental Solution (IES) will be utilised to investigate potential energy savings and design optimization strategies in the subsequent research phase, to develop an enhanced breed of houses aligned to thesmart grid system. Study results confirm great potential of this relevant house type, connected to energy conservation and on-site generation therefore providing valuable insights for design improvements to the existing and future stock. Furthermore, household income increase and limited use of air conditioning indicate occupants’ ability to achieve better living standards but cautious spending on AC usage deterred by high energy costs. Such behavioural pattern can be further enhanced through smart meter installation to better inform occupants about their energy consumption.
... This figure is even more relevant when considering the forecast 3.1% annual growth of energy usage (APERC, 2006) and makes the implementation of effective energy conservation strategies in the housing construction sector an urgent matter. Kubota et al. (2011) broke down energy use in a typical terrace house, one of the most common types in the country, into five categories: cooking (45%), cooling (29%), others (11%), lighting (8%) and laundry/cleaning (7%). This included both electricity (major usage) and fossil fuel energy (cooking usage). ...
... below, which shows data about household size, income and employed family members, comparing survey results with data from literature and statistical records. The average household size from the survey is higher than the national figure, yet lower than an earlier study by Kubota et al. (2011). In addition, respondents also earn relatively high salaries, with higher average household income compared to the national value, and at least two employed household members. ...
... High household income implies better purchasing ability and aspiration to better living standards. This is supported by various studies - (Toe, 2013;Kubota et al., 2011;Isa et al., 2010) -that recorded an increasing number of air conditioning (AC) systems in terrace houses, previously considered luxury items. A cascade effect drives the energy demand increase (Endut and Jajri, 2010). ...
... The AC usage in residential areas is typically high and influences the load curve significantly. Moreover, Kubota et al. (2011) conducted a survey in Johor, Malaysia and calculated the yearly average electricity consumption for each appliance based on the quantity, usage time, and electric capacity of each item. They found that AC is the biggest contributor with the highest electricity Table 1 Past studies on field measurements and surveys of residential electricity consumption. ...
... Tjaden et al., 2015 Germany 74 households -Gaps in the measurements were replaced with measured data from the same time frame of the respective day of the previous week. Kubota et al., 2011 Johor, Malaysia 388 households (survey) -Results only represented the area in Johor. Kavousian et al., 2013 USA 1628 households -Use of aggregate (low-resolution) consumption data -Using energy intensity as the only indicator for analyzing electricity consumption Kindaichi et al., 2017 Japan 100 detached houses -The data from 2007 was used, which questions the reliability of the results. ...
... This is because the heat load was large right after the AC was turned on. According to Kubota et al. (2011) and Zaki et al. (2017) the Malaysian AC usage behaviour differs between daytime and nighttime since most Malaysian residents regularly use the AC during their sleeping hours and hardly use the AC during at daytime. Meanwhile, Fig. 12(c) shows that the peak demand of other appliances occurred in the morning i.e. from 5:00 to 9:00. ...
Article
In residential buildings, accurate forecast of time-varying electricity demands is important for the estimation and prediction of electricity consumption. Information of the end user's electricity consumption patterns is necessary as it has a significant impact on the load curve in the utility grid. Thus, this study aims to provide detailed information on the electricity use and indoor thermal environment for typical residential buildings. Field measurements were conducted in 19 selected dwellings in Kuala Lumpur, Malaysia to specifically measure the total and the air conditioner (AC) electricity usage along with the indoor thermal environment. There were significant differences in the total electricity consumption among low-, middle-, and high-income dwellings. However, for the AC electricity consumption, the different income groups do not display notable differences. This might be due to the occupant behaviour of using the air conditioner mostly during sleeping hours. The measurement results of all targeted dwellings showed that the daily averages of the total and the AC electricity consumption are 14.5 kWh/day and 3.9 kWh/day, respectively. The daily averages of the AC electricity usage in the living room and the bedroom are 2.7 kWh and 4.4 kWh, respectively. The fraction of the daily peak demand from all targeted dwellings shows that the peak at the nighttime is due to the use of the air conditioner. Moreover, the patterns of hourly indoor thermal environment showed an average of 30.1 °C (living room) and 29.3 °C (bedroom). Generally, the comfort level for the indoor temperature lies between 23 °C and 26 °C, while for relative humidity, the comfortable range is between 40% and 70%. These findings provide preliminary understanding of the detailed characteristics of residential electricity use and indoor environment in Malaysian dwellings and can be used to predict the electricity demand in the future.
... Figure 4 shows the climograph for Malaysia, based on secondary data from the weather station in Sultan Abdul Aziz Shah Airport, Selangor Malaysia [31]. Malaysia has a hot and humid climate throughout the year; therefore, the monthly average outdoor temperature and humidity is almost constant in most towns, as confirmed by Kubota et al. [32], Swarno et al. [23], and Zaki et al. [33]. The average monthly outdoor temperature was 27.8 °C, and the average monthly relative humidity was 82%. ...
... Figure 4 shows the climograph for Malaysia, based on secondary data from the weather station in Sultan Abdul Aziz Shah Airport, Selangor Malaysia [31]. Malaysia has a hot and humid climate throughout the year; therefore, the monthly average outdoor temperature and humidity is almost constant in most towns, as confirmed by Kubota et al. [32], Swarno et al. [23], and Zaki et al. [33]. The average monthly outdoor temperature was 27.8 • C, and the average monthly relative humidity was 82%. ...
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Energy-saving strategies are required to address the increasing global CO2 and electrical energy consumption problems. Therefore, the determinant factors of electrical energy consumption consist of socio-demographic changes, occupant behavior, house and appliance characteristics, or so-called techno-socioeconomic factors, which all need to be assessed. Statistics models, such as the artificial neural network (ANN), can investigate the relationship among those factors. However, the previous ANN model only used limited factors and was conducted in the developed countries of subtropical regions with different determinant factors than those in the developing countries of tropical regions. Furthermore, the previous studies did not investigate the various impacts of techno-socioeconomic factors concerning the performance of the ANN model in estimating monthly electrical energy consumption. The current study develops a model with a more-in depth architecture by examining the effect of additional factors such as socio-demographics, house characteristics, occupant behavior, and appliance characteristics that have not been investigated concerning the model performance. Thus, a questionnaire survey was conducted from November 2017 to January 2018 with 214 university students. The best combination factors in explaining the monthly electrical energy consumption were developed from occupant behavior, with 81% of the variance and a mean absolute percentage error (MAPE) of 20.6%, which can be classified as a reasonably accurate model. The current study’s findings could be used as additional information for occupants or for companies who want to install photovoltaic or wind energy systems.
... Nevertheless, people living in a hot and humid country like Malaysia tend to use the AC by setting it at the lowest set point temperature [3]. The average set point temperature has been found to be 20.8℃, while more than 15% of the respondents IOP Publishing doi: 10.1088/1757-899X/1051/1/012073 2 set the temperature to between 16 and 17℃, which is considered the lowest set point temperature [4]. Therefore, the temperature settings are used as a reference and the indoor temperature is somewhere between the AC air temperature and the ambient temperature. ...
... This is due to occupants of office buildings in tropical regions who prefer the indoor temperature to be lower than 20°C. This type of preference occurs because of the high daytime outdoor temperature i.e. approximately 32°C [4,5]. ...
Article
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The use of an air conditioner (AC) becomes essential in residential buildings, particularly in a hot and humid climate to optimize indoor thermal comfort. To accelerate the process of space cooling, occupants tend to use the lowest set point of the AC thermostat setting to achieve the desired thermal comfort in the indoor environment. A field study was conducted to investigate the occupants’ thermal preferences in experimental living rooms at four AC set point temperatures (16°C, 20°C, 24°C, and 28°C). The indoor thermal environmental measurement and questionnaire survey were conducted on 63 respondents with 252 samples. The results of the thermal sensation vote (TSV) revealed that at the AC set point temperatures of 16°C and 20°C, 38% and 62% of the respondents voted ‘cold’, respectively. Meanwhile, they voted ‘a bit warmer’ for their thermal preference (TP). At the set point temperature of 24°C, 41% of the respondents voted ‘neutral’ for TSV, while 54% voted ‘no change’ for TP. At the same time, for the set point temperature of 28°C, 38% of the respondents voted ‘slightly warm’ for TSV and ‘a bit cooler’ for TP. In short, the respondent might have different thermal preferences even though they were experiencing the same thermal condition. This finding also indicated that there is a limit to how much the AC can provide uniform thermal satisfaction among occupants in the same room with a single control of the set point temperature.
... Based on a study about the energy consumption and air conditioning usage in residential buildings of Malaysia [1], two surveys were conducted in Johor Bahru. The first survey was carried out on October 2004 to understand the occupants" behaviors about air-conditioning usage [1]. ...
... Based on a study about the energy consumption and air conditioning usage in residential buildings of Malaysia [1], two surveys were conducted in Johor Bahru. The first survey was carried out on October 2004 to understand the occupants" behaviors about air-conditioning usage [1]. The second survey was done in October 2009 to reveal household consumption structure in the same residential area. ...
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High power consumption cooling devices such as air conditioners increase electricity power demands. In this project, an alternative solar-powered cooling system is suggested to reduce the air temperature to human comfort level and reduce their household electricity usage. Plants are used in this project to undergo transpiration, which is a natural process where moisture is carried from the roots to the underside of the leave to be evaporated. Heron‟s fountain technique was applied to reduce the power consumption of the water pump by lifting up water using gravity. Power consumption is reduced to 23 watts per hour and the air temperature around 1 °C to 2 °C of a 90 square feet single bedroom depending on the surrounding condition. This gives human a range of thermal comfort of 25 °C to 29 °C in residential buildings.
... Consequently, a higher percentage of AC installations was exhibited in bedrooms than in communal spaces, such as living areas or dining rooms by Kubota et al. (39). In general, rooms with larger floor areas and better natural ventilation can potentially increase indoor wind speed, resulting in the mitigation of the thermal discomfort of occupants. ...
... In the case of working rooms at home during the MCO period, the RRRs for stopping and starting AC use during this period were 0.287 and 0.527, respectively, which were statistically significant. Since these RRRs are less than 1, the changes relative to not changing people install ACs in private rooms more often than in communal spaces, such as living areas or dining rooms (39). Therefore, people working remotely in communal spaces, accustomed to using ACs at the office, could easily curb AC use during the MCO period. ...
Article
Remote work (working from home) became a norm rather than an exception for the global workforce during the COVID-19 pandemic, influencing every facet of life in both positive and negative ways. The stringent action of the Malaysian government in enacting the Movement Control Order (MCO) motivated the investigation of its impact on the energy consumption behaviour of working people regarding air-conditioner (AC) use. To this end, this study conducted a cross-sectional survey through an online platform. An ordinal logistic regression model (ORL) was used to analyse the collected data of 1873 respondents to determine the factors influencing the ordinal variable of interest, AC-usage behaviour during remote work. Next, the variable with unordered categories, the MCO-induced change in AC-usage behaviour, was analysed using a multinomial regression model (MLT) to identify the potential determinants. Finally, a reason analysis unveiled aspects behind the transition in AC use during remote work. This study identified stopping AC use during remote work despite using it at the office before the MCO period as the most significant change in AC-usage behaviour due to MCO. This change was frequently adopted by people with medium-level incomes and high electricity bills. By contrast, participants unfamiliar with their electricity bill were most likely to start AC use during remote work, although they did not use it before the MCO. Participants working remotely in the communal spaces of their houses preferred to stop using ACs during MCO compared to private room users. Furthermore, age group and ethnicity significantly influenced AC-usage behaviour in remote work and changes in such demeanours. These findings recommend policy interventions to expedite limited AC use for a sustainable energy sector, even during future climatic emergencies.
... The saving energy concept in this type considers the low-speed rotation for the compressor but rise in high rate acceleration to achieve the set temperature. At this time the compressor slows down the rotation speed but in such manner that this running maintains the gas pressure for keeping the temperature constant by fluctuating over the setting value with low ripple rate [65], [66], as shown in Fig. 5. The block diagram of an air-conditioner with a variable-speed compressor/motor is demonstrated in Fig. 6. ...
... Then the compressor smoothly starts run with growing speed according to the difference between the set and the actual temperatures. The electronic-based control strategy of variable speed variable voltage (VVVF) performs a significant behavior with lower consumption as compared with the traditional one, which consumes about three times its rated power [65], [68]- [70]. ...
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DC power has spread back, especially in residential microgrid PV systems, as a variety of modern electronic loads became available commercially. The compatibility of household appliances with a DC distribution system with the best voltage-level is the areas that not yet made a practically extensive appearance, and it is still in the research phase. This work mainly explores these issues by 1) providing a review on the concerning research efforts, 2) identifying the gaps in the existing knowledge, and 3) exploiting the recent advances in the commercial household appliances. The paper discusses the electrical diagrams of household appliances, classifying them, and understanding how each one consumes the power. The work also extrapolates a new architecture to reduce the losses of the overall system and grow its efficiency up. These improvements are achieved by proposing a DC-environment with two levels of voltage to cover all the recently produced appliances. The energy transfer efficiency is the key factor that calculated to evaluate the appliance performance. The study outcomes can serve as a guide for establishing standardizations for DC microgrid and designing a more efficient DC power distribution networks with minimal energy converters.
... The monthly outdoor temperature is almost constant, i.e., the range of a minimum of 26-28 • C and a maximum of 31-33 • C, with an average temperature difference of 6.7-8.3 • C. The annual relative humidity (RH) value ranges from 58 to 66%. Additionally, it receives abundant solar radiation to produce sustainable solar energy [32]. The daily average, maximum, and lowest outside temperatures data of Weather Underground recorded from the weather station at Sibu Airport are shown in Figure 2 [33]. ...
... The annual relative humidity (RH) value r from 58 to 66%. Additionally, it receives abundant solar radiation to produce susta solar energy [32]. The daily average, maximum, and lowest outside temperatures d Weather Underground recorded from the weather station at Sibu Airport are shown i ure 2 [33]. ...
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The Sustainable Development Goals of the United Nations strive to maximize development needs, while minimizing environmental deterioration, without jeopardizing the needs of future generations. Nevertheless, due to urbanization, the escalating trend in natural-resource use, particularly electricity and water, is currently a crucial challenge for sustainable development. One of the promising options is the smart home, which is an extension of building automation with smart characteristics in monitoring, analyzing, controlling, and cloud computing with networked smart devices. Due to the lack of appropriate infrastructure and conscious consumption, its global adoption in the construction industry remains low. We present a technical feasibility of a multi-functional experimental smart home to support the Sustainable Development Goals of the United Nations in terms of water and energy conservation. The layered architecture of the cloud platform with an application program interface enables seamless integration of heterogeneous smart-home technologies and data sources. Use cases demonstrated its capacity to conserve electrical energy and water resources in support of the United Nations’ Sustainable Development Goals. Aside from that, the smart home’s electricity self-consumption of at least three autonomy days was confirmed with zero emissions and electricity bills, and a reduced supply-water consumption.
... ( Kubota et al. 2011). ...
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Household electricity wastage poses a sustainability issue. Ergonomic interventions that prevent wastagethrough technological innovations are expensive and complex,making consumers unwilling to adopt them.The study aimed to investigate the motivations and impediments in avoiding electricity wastage. Thirteen Repertory Grid interviews were conducted on household electricity users relating to the behaviour of those living with them.The key motivational themes found were altruistic and egoistic reasons while the impediments were perceived behavioural control, hedonism and self-efficacy.Based on the research findings, a behavioural-modification framework was developed to encourage consumers to adopt a higher level of responsible electricity practice through the following suggested interventions – (1) reframing sustainability from ‘future-for-others’ to ‘present-for-us’, (2) clarifying responsible consumption and (3) performance feedback. The research identified the key motivations and impediments of being a responsible household electricity user and provided a framework to encourage a higher responsibility level. Practitioner Summary Household electricity wastage poses sustainability issue: excess CO2& high costs. We developed a mindset changing behavioural modification framework. We investigated HFE issues: motivations & impediments of avoiding the wastage, i.e. altruistic, egoistic, behavioural control, hedonism & self-efficacy. The framework provides governments insights into strategies to address the wastage.
... [3]. Refer to the previous study, most of the buildings prefer to assign maximum cooling load to accommodate the comfort level [4]. Therefore, the energy demand especially in cooling load has increase and currently burdens the building owner. ...
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Wall is one of the structures elements that resist direct heat from the atmosphere. Modification on several structures is relevance to reduce filtrate thermal movement on wall. Insulation material seems to be suitable to be implemented since its purpose meets the heat resistance requirement. Insulation material applied as to generate positive impact in energy saving through reduction in total building energy consumption. Fiberglass is one of the insulation materials that can be used to insulate a space from heat and sound. Fiberglass is flammable insulation material with R Value rated of R-2.9 to R-3.8 which meets the requirement in minimizing heat transfer. Finite element software, ABAQUS v6.13 employed for analyze non insulated wall and other insulated wall with different wall thicknesses. The several calculations related to overall heat movement, total energy consumption per unit area of wall, life cycle cost analysis and determination of optimal insulation thickness is calculated due to show the potential of the implementation in minimize heat transfer and generate potential energy saving in building operation. It is hoped that the study can contribute to better understanding on the potential building wall retrofitting works in increasing building serviceability and creating potential benefits for building owner.
... For instance, refrigeration and air-conditioning systems are two thermal systems that place a very high demand on power. It is reported that air-conditioning and refrigeration appliances consumed the largest amount of electricity domestically (Kubota et al., 2011). Also, in major office spaces, the combined wattage demand of air- condioners and refrigerators exceed those of other appliances. ...
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The study investigated the comparative performance of R290 and R22 refrigerants in a domestic air-conditioning system. It used a 2 hp window split air-conditioning system with Capella D oil as lubricant. Performance analysis which include coefficient of performance, cooling capacity, energy consumption and thermal conductivity and viscosity at vapour and liquid phases were determined. The results were employed to carry out the comparative analyses of the efficiency of R290 as a replacement alternative to R22 refrigerant in a domestic air-conditioning unit. The findings show that although R22 performed better in terms of its coefficient of performance and cooling capacity, R290 however showed better results in terms of its energy consumption, thermal conductivity and viscosity at the liquid and vapour phases. Further to this, there is no marked difference in the pull-down time results. The consequence of the results is that R290 can be a suitable alternative air-conditioning refrigerant to R22, the performance notwithstanding. However, the performance can be further improved with a reconfiguration of the thermo-physical properties of the thermodynamic system such as the lubricant. This can be achieved by taking advantage of the ability of metallic and non-metallic nanoparticles to improve the thermal and physical properties of the lubricant and by extension the thermodynamic system. Thus, with improvement in the thermal conductivity and viscosity of the lubricant, there can be further improvement in the performance of R290 as air-conditioning refrigerant. Going by the findings and coupled with the fact that R22 is environmentally malignant, R290 can become a suitable alternative in the long run.
... A heating load of 10kW is specified to the evaporator. The average Malaysia electricity consumption is about 1kW [13]. Therefore, the system can provide cooling up to ten households. ...
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This paper presents a mathematical modelling on the evaluation of cooling, heating and power performance of a hybrid system of Organic Rankine Cycle and Vapour Compression Cycle. The system is assumed to be powered through solar parabolic trough collector and is able to generate a cooling power of 10 kW. Refrigerants R134a or R245fa are chosen as the working fluid of the system. The system is constructed using commercial energy modelling tool AspenPlus. Analysis is performed to determine the effect of changing the mass flow rate split ratio on the energy output. The effect of using subcritical and supercritical working fluid is also compared. Particular attention is paid toward the condition where the power output is equivalent to the energy consumption in view of creating a self-powered cooling and heating system. The result shows that the coefficient of performance for system using R245fa is higher compared to that using R134a. However, the system using R134a allows a self-powered cooling and heating system to be achieved to be achieve at a much higher mass split ratio, resulting the system to be 35% more efficient in the performance.
... Buildings energy consumption is expected to frequent changes in the way how they are used, maintained and refurbished that may affect their energy consumption and supply costs (Gruber et al., 2015).In addition, energy consumption for building cooling system accounts for 57% from total energy consumed in buildings (Rismanchi et al., 2012). Specifically, some studies in Malaysia showed that the average rate of building cooling energy consumption increased by 1.4 % per year (Kubota et al., 2011). The extent of this cooling energy consumption is 60% outpaced from total building energy consumption in Malaysia (Chong et al., 2015;Saidur et al., 2009). ...
Article
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The building cooling system is served as important function providing a comfortable environment for building occupants. Indeed, the building cooling system is a demand-oriented with sustainable building management strategy which is desirable for balancing between both building usage and energy demand. At present, the management of the cooling energy building demand often raised concerns on potential reduction of building Operational and Maintenance (O&M) cost. The integration between O&M cost involved was used as a benchmark strategy for building energy-saving potential with regard to high system performance. To address these issues, this study focused at the medium size office building Universiti Teknologi Malaysia (UTM). The present work integrates centralised building cooling system, Heating, Ventilating and Air Conditioning (HVAC) equipment and cooling energy demand loads. The cooling energy data is based on site-measured data collected and engineering-cost analysis. Engineering-cost analysis results demonstrated that the operation and maintenance cost of cooling tower system increased by 3 % per year due to the annual inflation rate. It is considered that method in this study can be applied to provide the guideline for building energy consumption and strategic management cost.
... To the best of our knowledge, none exists thus far. The closest that we could found was the survey done by [1], which focused their study on the use of air conditioning in the residential buildings in Malaysia. The survey, which was done in 2010, covered the residents in one of the cities in Malaysia, which is Johor Bahru. ...
Conference Paper
In the recent years, the world has witnessed significant surge in energy consumption due to the increasing population. The world’s population exceeded 7 billion in 2011 and is predicted to be more than 9.3 billion by 2050. Increase in the population will increase the energy consumption, which will result in a number of negative consequences. Thus, it is crucial to plan, monitor and subsequently manage the energy consumption in order to control and minimise its negative impacts. To do this, it is necessary to first obtain the information on the current practice in energy consumption amongst the domestic consumers. In our study, a survey to obtain the information was performed. Focusing on the electricity consumption, information on the residents ownership with respect to the six identified electrical appliances that contributed most to the electricity consumption and their behaviour in general and in using the appliances were collected. The behaviour was measured by means of the ten predefined electricity saving behaviour gathered from the literature and previous research work. Analysis results showed that all of the appliances significantly affect the household electricity consumption and four out of the ten electricity saving behaviour is significant to the household electricity consumption. Findings can serve as a basis for energy consumption planning and related areas such as the development of household electrical energy consumption recommendation model.
... The long-term electric consumption data are adopted from [42] to determine the electric consumption in a year. Based on the surveyed data from [43], the percentage of electricity consumption and the air-conditioner is about 14% and 21%, respectively. Therefore, we calculate the electricity consumption by subtracting the overall electricity consumption from the electrical usage of the heater and air conditioner. ...
Article
This study proposes a design of polygeneration system based on solid oxide fuel cell to supply electricity, hot water, cooling, and hydrogen. This system also integrates the stationary supply for electric and hydrogen cars. The polygeneration system is developed based on energy, economic and environment simulation models by taking into account its application for the residential building. Four system configurations were designed based on the grid connection and the vehicle type and subsequently evaluated to determine the performance of the system in regard to the criteria such as efficiency, reliability, primary energy saving, cost saving as well as carbon dioxide reduction. Moreover, a strategy of selling the available hydrogen was also considered to analyze the competitiveness of the proposed system with the conventional separated system. Depending on these criteria, analysis of fuel cell size with respect to the coverage of demands was also conducted. The proposed system achieved primary energy savings, cost saving and emission reduction of about 73%, 50% and 70% respectively. The hydrogen selling strategy has a significant effect in reducing energy cost close to 51% for the configuration with electric vehicle station.
... Cooling system and lighting consume the most energy compare to others housing appliance [4]. The design of the building envelopes and material used play an important role in reducing the energy consumption of the building. ...
Article
Energy consumption for residential use in Malaysia is keep increasing yearly in order to maintain the internal thermal comfort of the building. Roof insulation material plays a vital role in improving the thermal comforts of the building while reduce the cooling load of the building. Oil palm industry in Malaysia had grown aggressively over the past few decades. Tons of oil palm waste had produced during the process such as empty fruit bunch fiber. Another waste material that available and easy to obtain is paper. Paper is a valuable material that can be recycled. Waste paper comes from different sources such as newspaper, office and printing papers. This study will take advantage of the available resources which could contribute to reduce the environment impact. The aim of this study is to investigate the thermal performance of roof insulation materials using mixture of oil palm fiber and paper pulp with different ratio and thickness. This study found that the thermal performance of the paper pulp is slightly better compare to the oil palm fiber. Thermal conductivity of the particle board reduces around 4.1% by adding the 10% of paper pulp into the total density of the particle board. By adding 75% of paper pulp, the thermal conductivity of the particle board could be reduced to 24.6% compare to the oil palm fiber board under the similar condition. Therefore, from this study, it could be concluded that paper pulp has high potential to be used as a building insulation material.
... The air-conditioning system was set at 20.8 degrees Celsius from 10:00 p.m. to 6:00 a.m. every day in the master bedroom and two other bedrooms on the first floor based on findings by Kubota et al. [38]. The electricity consumption was assumed to be constant throughout the operation of the house. ...
Article
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The building industry has a significant impact on the environment due to massive natural resources and energy it uses throughout its life cycle. This study presents a life cycle assessment of a semi-detached residential building in Malaysia as a case study and assesses the environmental impact under cradle-to-grave which consists of pre-use, construction, use, and end-of-life phases by using Centre of Environmental Science of Leiden University (CML) 2001. Four impact categories were evaluated, namely, acidification, eutrophication, global warming potential (GWP), and ozone layer depletion (ODP). The building operation under use phase contributed the highest global warming potential and acidification with 2.41 × 10 3 kg CO 2 eq and 1.10 × 10 1 kg SO 2 eq, respectively. In the pre-use phase, concrete in the substructure has the most significant overall impact with cement as the primary raw material. The results showed that the residential building in Malaysia has a fairly high impact in GWP but lower in acidification and ODP compared to other studies.
... In particular, air conditioning system significantly contributed to the residential electricity consumption. It is reported that AC system consumed about 17 percent of total energy in household sector, and followed by ceiling fans (10 percent) [12]. However, using ceiling fan as a substitute for air conditioning is expected to reduce energy consumption without sacrificing thermal comfort through creating air motion in the residences. ...
Article
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Globally, building sector currently consumes around of 40 percent of total energy and it is predicted to further rapidly increasing up to 80 percent by 2040. This study aims to investigate some design options to achieve thermal comfort and reduce energy consumption. In Indonesia, building sector consumes around of 37.8 percent of the total nationwide energy consumption. Computer simulations using EDGE and EnergyPlus were performed in this study to obtain embodied energy value and obtain operative temperature respectively. EDGE uses monthly quasi-steady-state calculation method based on the European CEN5 and ISO 13790 standards while EnergyPlus uses dynamic simulation model based on hour-by-hour (or higher resolution) outputs. A single storey building with 12 different parameters and design configurations including one base model were developed for this simulation. Some parameters were evaluated such as wall materials, roof materials, Window to Wall Ratio (WWR), window shading, ventilation opening, solar PV and ceiling fan. The simulation results showed that modification of U-value of wall and roof, increased WWR value, presence of window shading, additional rooster above windows with WWR of 9 percent and additional ceiling fans would optimize the embodied energy saving of building by 20.2 percent. Under these circumstances, final embodied energy saving of building was around of 63,939 MJ. This result was 10,837 MJ higher than that of the base model. Simulation results showed that the operative temperature mostly did not exceed the upper comfortable limits.
... 00 Source: Saidur, M. et al. (2007), JPPH (2013), DOSM (2014a), DOSM (2014b), EPU (2014), KRI (2014)Note:Kubota et al. (2011) conducted a survey on household energy consumption in Johor, Malaysia to analyse energy requirements for cooling, cooking and appliances. Data from this study on energy requirement for cooking, cooling and electric appliances per household is used in MAED for the base year. ...
Conference Paper
This thesis studies the challenges of formulating strategies for decarbonising the energy systems in many countries that are battling to reduce carbon emissions and seriously considering incorporating environmental issues in the process of energy planning and policy-making. It presents the development of mathematical models and analysis to obtain insights on optimal and near-optimal decarbonisation strategies. The energy system of Malaysia is used as a case study to analyse energy related issues and investigate the decarbonisation of the energy systems. Under the landscape of demand–supply uncertainties at a multiregional level, a novel Modelling to Generate Alternatives (MGA) hybrid (MAED-OSeMOSYS) approach has been developed to capture the electricity trade option between three regions of Peninsular, Sabah and Sarawak, analysing in detail the end-use technologies of various sectors and the integration of end-use technologies with the power sector. It analysed the possibility of achieving least-cost optimal decarbonisation targets in Malaysia and concluded that the development of advanced and clean technologies needed in the system across all sectors, mainly power, industry and transportation. Further, it also investigated the near-optimal decarbonisation strategies that provided different insights on the possible evolution of a low carbon electricity sector in Malaysia with the implementation of the MGA technique. Additional investments and flexibility in categories of technology constraints imposed in the system. These constraints influence the type of technology to be deployed and make a difference in the diffusion of the power technologies, which result in carbon emissions reduction in the system. The application of the MGA technique provides researchers with the flexibility to explore alternative pathways within a cost optimal solution range, which provides new knowledge in the application of this technique to the OSeMOSYS model. This thesis provides insights to policy makers of middle-sized countries on feasible decarbonisation and investment strategies that may have important investment, trade and policy implications and relevance at a national and international level. This research on its own merits gives Malaysia and other similar middle-sized developing countries a high added value to its energy modelling analysis, which is scarce in comparison to energy modelling research of developed countries.
... Also, the findings identified failure to clean the heating, ventilating and airconditioning systems, to close doors and windows while ACs were on and avoidance of the use of efficient refrigerants and new ACs are major factors that negatively impact EE for the manufacturing industries. The findings are consistent with similar studies conducted by Kubota et al. (2011) on energy consumption of air-conditioners in Malaysia. ...
Conference Paper
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Building Information Modelling (BIM) implementation in the design and construction phases of road projects has increased significantly during the last decade, while the application of BIM for the operation and maintenance phase of roads is less developed. BIM can offer an integrated and unified asset management process based on all phases of a road project, leading to significant savings in time and cost. COBie (Construction Operation Building information exchange) is the data handover solution applicable for vertical infrastructure (buildings). Australian and New Zealand Road Authorities are working on an adaptation of COBie, called CONie (Construction Operation Network information exchange), that considers linear infrastructure requirements for asset management. One of the challenges required to support the development of this data handover framework is the lack of a harmonised data schema for asset management in terms of asset name, definition, and categorisation. The purpose of this paper is to argue that developing and utilising a harmonised and synthesised object model of road assets will assist Australasian road organisations to increase efficiency in asset management, especially through collaboration. This paper describes the procedure followed to harmonise road asset databases that has been used as a basis for developing CONie. The described aim was achieved through collecting relevant data from Road Authorities and the developers of road standards in Australia and New Zealand. The collected data was harmonised and synthesised. The harmonised database was then mapped to the building Smart ifcRoads project. Regarding the existing road assets, a categorisation system is suggested by authors. It introduces the main categories including relevant subcategories and asset types. The developed database of road assets provides a basis for asset management, operation and maintenance purposes by road organisations beside being used for CONie development.
... Also, the findings identified failure to clean the heating, ventilating and airconditioning systems, to close doors and windows while ACs were on and avoidance of the use of efficient refrigerants and new ACs are major factors that negatively impact EE for the manufacturing industries. The findings are consistent with similar studies conducted by Kubota et al. (2011) on energy consumption of air-conditioners in Malaysia. ...
Conference Paper
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The COP21 Paris Agreement and the Glasgow Climate Pact require urgent abatement of the current fossil-based energy consumption. In 2021, the Global Status for Buildings and Construction Report pinpointed buildings as responsible for 36% of the global energy consumption; 36% of this energy consumption by end-use of commercial buildings corresponds to space heating. Heating loads in commercial buildings can be reduced by building envelope retrofits, efficiency upgrades of heating equipment, energy management, and influencing energy users' behaviour. Traditional engineering assessment methods use capacity metrics such as the building load coefficient (BLC) for the building infrastructure or the coefficient of performance (COP) for heating and cooling equipment to measure how far the improvements can go. In-office buildings, one way to optimize operation systems for space heating is to modify set points, but the set parameters constrain the associated savings; for example, changes to the indoor temperature are limited, to maintain a safe indoor environmental quality (IEQ). However, these capacity metrics and constraints do not reflect the interaction between building occupants and the heating system, nor the resultant capacity for energy reductions. This paper reviews the literature on energy assessment tools focused on occupant heating behaviour. The findings suggest the need for a standard method to assess occupants' behavioural aspects related to the final energy use in commercial buildings and the consequent potential for energy conservation.
... The testing focused on gathering data from the master bedroom since it recorded a percentage of 98% in terms of air conditioner activation frequency from a sample number of 332 residents in Malaysia based on a previous research in 2011 [11]. The testing is conducted with the following placements: ...
... For residential buildings, Kubota et al. (2011) found that 65 % of homeowners in Malaysia use air-conditioning at least six hours a day. Meanwhile, Rahman et al. (2017) indicated that fans are among the most popular electrical appliances in households. ...
... Accordingly, we assume that these appliances are commonly used and owned by households while other appliances are not as important or rarely used such as microwaves and vacuums (Ponniran et al., 2012). The result of this study is similar with Kubota et al. (2011) that revealed the highest percentage of appliances ownership in Johor Baharu were refrigerators, washing machines, rice cookers, televisions and ceiling fans. This is might be respondent sharing similar socioeconomic characteristic between households in Johor Baharu and Seremban. ...
Article
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The growing trend of energy consumption in urban area has created negative impacts to the urban environment because the issues related to energy use and urban developments are largely dependent on human aspects and mobilized by the inhabitants of the city itself. This study aims to estimating the electricity consumption with regards to electrical appliances usage and carbon emissions in domestic sector of urban area. The study revealed that average electricity power consumption was 648.31 kWh. Meanwhile, refrigerator and air conditioning recorded as the highest electricity consumption appliances compared to other appliances. In terms of type of house, household from bungalow house consumed more electricity power and resulted to high carbon emissions compared to other households. The study suggested that the level of knowledge, awareness, commitment, attitude and behavior of electricity consumption among household should be intensified. Besides, the number of energy saving appliances also needs to be improved and encourage smart energy consumption that led to the sustainable urban development.
... In addition, Mekhilef et al. [7] reported that the average usage of AC overnight was 1086 kWh, higher than the daytime AC usage of 730 kWh per year in a high-rise residential building in Kuala Lumpur. Kubota et al. [8] conducted a survey on energy consumption and AC usage in terrace houses in Johor Bahru, Malaysia, and found that 80% of the respondents switched on the AC by 23:00 and that more than 50% of them continued to use AC until 05:00. In the study by Ono et al. [9] that involved multiple dwellings in Kuala Lumpur, AC usage was found to be mostly frequent at nighttime, including the sleeping period. ...
Article
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Comfort temperature and sleep quality involving 20 participants were determined in two cases: Case A (arbitrary, controlled air-conditioner setting) and Case B (adjustment of 3 °C higher than the setting of Case A with cool bed linen). Data of indoor thermal comfort and electricity consumption were collected every night throughout the measurement period. Questionnaires on thermal comfort and sleep quality were distributed twice a night for a duration of three nights for each case; the first night was for respondents’ adaptation and the following two nights were for measurement. The sleep quality of the respondents was objectively measured using a commercially available activity tracker. Results found that most respondents were thermally comfortable in both cases, with 39% lower energy consumption reported for Case B compared to Case A. The thermal conditions of Case B were found to be more tolerable than those of Case A. Most respondents reported to have a calm and satisfied sleep for both cases. Comfort temperature and Sleep Efficiency Index (SEI) were found to be maintained in both cases.
... Many households had many electric fans, and they were regularly used. Unlike the previous study in Malaysia [28], few households had ceiling fans in Chiang Rai, and most ceiling fans were attached to lighting. Most households in rural areas did not use any heating equipment. ...
Article
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This study investigated the differences in household energy consumption between urban and rural households in northern Thailand, with a particular focus on air-conditioner ownership and use. In-depth visits to 32 households in Chiang Rai were undertaken in 2016 and 2017. The data collection covered six aspects: household attributes, ownership of electric appliances, use of air conditioners (ACs), intentions to conserve electricity, desire to purchase electric appliances in the future, and prospects for a future lifestyle. Traditional stilt houses can still be found in rural areas, but ACs have been introduced as rural houses have modernized. The typical period of AC use in rural areas was 2 to 4 months during summer. In urban households, ACs were used for a longer period, from 3 to 12 months each year. In addition, rural households usually used ACs for only a few hours each day before sleeping, whereas urban households often used them while they slept and some used them throughout the day. Households with children and grandchildren tended to use the AC for longer periods. These results suggest that promotion of environmentally friendly lifestyles for younger adults to control overuse of ACs would be key to reducing energy consumption in the future.
... Meanwhile, the duration for air conditioners and fans is 8 hours. The operating durations used for these appliances are consistent with a survey finding as well as SIRIM assumptions on typical time used for common household appliances in Malaysia (Kubota et al., 2011). For refrigerators and televisions however, the annual electricity consumption was taken directly from the equipment performance test report by SIRIM, which was provided by the participating companies. ...
Article
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One of Malaysia's key strategies to promote efficient use of energy is by implementing the Minimum Energy Performance Standards (MEPS). Under this regulation, five common household appliances (air conditioner, refrigerator, fan, television, and lamp) must comply with MEPS requirement in order to be sold in Malaysian market. This study collected sales data from major suppliers to estimate the annual sales volume of MEPS-compliant appliances from 2013 to 2015. The sales estimates were used to determine the total electricity consumption and saving during the same time period. The study found that the local market is already saturated with 5-star rated televisions and fans in 2015. Meanwhile, the lamp market proportion is dominated by compact fluorescent lamps (CFL) with efficacy range from 50 to 55 lumens/watt. By the end of 2015, the total cumulative annual electricity saving gained after MEPS implementation is 2,685 GWh, which translates to a total annual cost saving of MYR 850 million and fossil carbon emission reduction of 1,726 ktCO2eq. By identifying and quantifying the multiple impacts of MEPS implementation in Malaysia, this work not only
... In contrast, TV, washing machine, standing fan, socket, iron, and RTM were recorded less than 1% for electricity usage. Basically AC is the highest electricity consumption and has a significant effect on the total electricity consumption compare to other appliances [17][18][19][20][21][22][23][24][25], but it is contradicted with this household. It might be due to the use of AC as shown in Figure 7 only during the sleeping time for around four hours since the owner also used the ceiling fan at the same time. ...
Article
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This paper describes the pattern of electricity consumption from total and selected domestic appliances at a typical terrace house in Malaysia. The measured appliances can be classified into four groups on the basis of pattern of use which are ‘standby’ (TV), ‘active’ (massage chair, charger of hand phone, laptop and power bank, washing machine, air-conditioners, iron, standing fan, shower heaters, rice cooker, toaster, microwave), ‘cold’ (refrigerator) and ‘cold and hot’ (water dispenser). The major contribution of monthly electricity consumption comes from ‘cold’ appliances that consume 118.8 kWh/month followed by ‘active’ appliances that consume 87.8 kWh/month and ‘cold and hot’ appliance with 52.5 kWh/month. ‘Standby’ appliances shown a small contribution to the total electricity with 0.9 kWh/month. The amount of energy consumed depends on time-of-use, power characteristics of particular appliances as well as occupancy period.
... Due to climate changes, air conditioning (AC) is used for thermal comfort and improvement of indoor air quality. However, AC energy consumption is the greatest energy use more than half of total energy consumption in buildings in tropical region [2]. In addition, predictions show that the energy consumption in developed countries will be increasing by 50% during the next 15 years [1] [3], the methods for estimating energy use are divided into two categories: Forward modeling and Inverse modeling. ...
Article
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The purpose of this study is to develop simplified cooling/heating load models for a various air-conditioned room, applying the Buckingham-Pi theorem. The model is used to estimate cooling/heating loads of air-conditioned room at reduced calculation time. An experimental room for cooling load had been set up at Chiang Mai University, Thailand in summer season during March to April in 2018. On the other hand, an experiment room for heating load had been set up at Mie University, Japan during December 2018 to February 2019. Room temperatures were set at 27 °C–25 °C for cooling and 24 °C–21 °C for heating. Collected data, such as room air temperature, room relative humidity, ambient temperature and solar radiation were used to calculate appropriate constants for cooling/heating load model. To validate the accuracy of the simplified model, calculated heating/cooling load from the model was compared to the calculated cooling/heating load from the traditional method. The results demonstrated that the simplified model developed from Buckingham-Pi theorem could estimate the cooling/heating load by low computational complexity with acceptable accuracy, comparing to results from traditional calculation method.
... Air Conditioning and Refrigeration (ACnR) systems have become an essential need in the recent years due to their importance to carry daily life applications like cooling control and, food and medical preservation. Malaysia, for example, is one of the countries that demand ACnR systems such as air-conditioners and refrigerators in 99% of its infrastructure; which in return consume 38% of the overall household energy consumption [1]. Many researches have been conducted to optimize the energy consumption of the ACnR systems by improving the coefficient of performance (COP) of the systems. ...
... When both systems (DHAPC and DHCBC) are combined together, they produce maximum reduction rates for the operative temperature and humidity of up to 20% and an average power consumption of 1.86 kW (680 kWh/year). Considering that the annual energy consumption for cooling (air conditioning and ceiling fans) in Malaysian housing is 1973.6 kWh/year (29% of total consumption) [28,30], this could represent an overall saving of circa 66% of power consumption for cooling purposes. ...
Article
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The pressure to provide social housing in a fast and economic way, as well as outdated regulations, constrain the design of these buildings, having serious implications for the comfort of occupants and the environment. This becomes more critical in hot-humid climates, such as Malaysia, with uniformly high temperature and humidity and low wind speeds. In its capital, Kuala Lumpur, an extensive program of construction for high-rise social housing is being carried out, however, shortly after the flats are occupied, or as soon as they can afford it, the residents fit wall mounted air conditioning units. This research started by looking at Malay vernacular architecture and the traditional strategies for ventilation and cooling. After a review of current building regulations and green tools employed in the country, two campaigns of fieldwork were carried out to assess the actual indoor and outdoor thermal and air quality conditions in the buildings, which were found to be inadequate for both the local regulations and international recommendations. The fieldwork also allowed the identification of the critical design issues to address. A ventilation and filtering ceiling system has been identified as one of the possible solutions for the current situation and has been tested through physical and computer models. The system improves comfort by reducing the air temperature, humidity, and amount of airborne particles and gases, as well as constantly providing an adequate airflow rate. It is the first attempt to develop what we have named the ‘airhouse’ standard for tropical countries.
Chapter
A substantial increase in world energy consumption has resulted in global rising pattern of building energy consumption. This trend is predicted to continuously rise as a result of economic prosperity and accelerated growth in living standards for shifting to contemporary lifestyle. Hence, the need for energy-efficient technologies in buildings is pivotal in order to reduce energy consumption and mitigate global environmental impact. Amongst these technologies, the application of air-to-air energy recovery system is proven as one of the significant solutions towards reducing energy consumption and providing fresh outdoor air in buildings. The system is defined as a mechanical system that able to conserve energy by transferring heat or mass from a stream at a high temperature to a low-temperature stream through a core. It was also able to remove stale, polluted air indoor spaces and replaces it with fresh outdoor air. In order to have an in-depth understanding of the system, this chapter discusses the mechanism and the application of the system in various climatic conditions such as winter and summer conditions; cold and extremely cold climate conditions; and hot–humid condition.
Chapter
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Conventional methods to analyze building energy are of limitation and difficult to determine the best building envelope structure, best material thermal properties, and the best way for heating or cooling. In this paper, the research on the inverse problem for phase change materials and the application in building envelope by our group was reviewed, which can be used to guide the building envelope thermal performance design, material preparation and selection for effective use of renewable energy, reducing building operational energy consumption, increasing building thermal comfort, and reducing environment pollution and greenhouse gas emission. This paper also presents some current problems needed further research.
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The construction industry and building materials consume a large amount of resources and energy during its extraction, production, construction, throughout its use and even demolition process, hence causing high impacts to the natural environment. Apart from an increase in energy use, these impacts of materials range from ecological degradation, harm to human health and global warming. In order to reduce the impacts, an assessment and analysis of building materials is crucial prior to the design and construction of buildings to predict the risks and enable the decision makers to minimize those risks. This chapter gives an overview of the lifecycle approach in material selection and the assessment and analysis of materials used in the construction based on ISO 14040:2006 and ISO 14044:2006. It also presents the results of the testing on life cycle assessment of common building materials adopted in mosque construction in Iraq based on five categories: global warming, ozone depletion, human toxicity, acidification and eutrophication. This study identifies the stages in which the materials have greater impact and give recommendation in reducing the overall impact of the materials used.
Chapter
This chapter aims to review the previous lighting technologies and discuss the impact of lighting design and user behaviour to the energy consumption of lighting as well as life cycle assessment of luminaires. Energy for lighting can consume between 31 % (in retail store applications) and 60 % (in educational settings) of an organization’s electricity budget. The price of electricity has never stopped its rising trend due to the global issue of energy scarcity. Therefore, a lot of efforts have been made in seeking ways to cut the electricity bill by reducing the energy consumption of lighting system and operating more efficiently. Insight will be shed onto the status of energy consumption by lighting, current lighting technologies, design and control, and the life cycle assessment of luminaires. Finally, a less resource depriving and low energy consuming way of using artificial lighting is proposed.
Chapter
Microalgae are considered one of the most promising feedstocks for biofuels. Interest in algae-based biofuels and chemicals has increased over the past few years because of their potential to reduce the dependence on crude oil-based fuels and chemicals. Algae is the most suitable and sustainable feedstock for producing green energy. However, numerous challenges associated with declining fossil fuel reserves as energy sources have accounted for a shift to biofuels as alternative product from algae. Algae is a source for renewable energy production since it can fix the greenhouse gas (CO2) by photosynthesis and does not compete with the production of food. This chapter, therefore, presents a review on the prospects of algae for biofuel production and also highlighted in this article is the macroalgae-based biofuels energy products obtained from algae as the raw biomass. In a nutshell, algae are the most sustainable fuel resource in terms of environmental issues.
Article
Accurate estimations of the stochastic natures of energy demand for air-conditioner (A/C) use, which are affected by the diverse occupant behaviour, are needed, for the design and operation of residential cogeneration systems and distributed generation systems coupled with renewable energy sources and supply-demand management technologies. However past studies have mainly focused on developed countries, and knowledge of tropical regions, including many emerging countries with large populations, remains limited. We conducted field measurements of occupants' A/C usage behaviour in 38 dwellings in Kuala Lumpur, Malaysia. Measured data were considered as a function of start and end times, duration, and frequency of A/C usage in each dwelling. Analysis showed that A/C events were rare during daytime; however, there was a drastic increase in the frequency of A/C usage at night. Based on this, a simple algorithm to synthesize stochastic time patterns of A/C operation schedules was developed. The validity of the model was demonstrated through comparison with observational data.
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