The Impact of the Application of Energy Efficiency Measures on the Energy Consumption of Residential Building
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The Impact of the Application of Energy Efficiency Measures on the Energy Consumption of Residential Building 1Nada Yamoul, 1Latifa Dlimi, 2Khalid El Harrouni and 3Achraf Chakir Baraka 1Department of Physics, Faculty of Sciences, Ibn Tofail University, Kenitra City (14000), Morocco 2National School of Architecture, Rabat, Morocco 3Department of Mathematics, Faculty of Sciences, Ibn Tofail University, Kenitra City (14000), Morocco Key words: Energy efficiency, thermal building Abstract: This study presents the impact of the regulations in Morocco, bioclimatic measures, thermal application of energy efficiency measures on the energy comfort, bioclimatic diagrams, thermal insulation consumption of residential building. In this study, we analyzed the importance of the application of the RTCM Corresponding Author: and bioclimatic measures located in different climatic Nada Yamoul contexts. The results showed that the thermal insulation of Department of Physics, Faculty of Sciences, Ibn Tofail the building envelope can reduce the energy consumption University, Kenitra City (14000), Morroco related to the heating and air conditioning. In addition, according to the results of that study, it was determined Page No.: 2218-2228 that using principles of the bioclimatic architecture and Volume: 15, Issue 10, 2020 appropriate design strategies are essential to achieve ISSN: 1816-949x indoor comfort conditions. Investigating and Journal of Engineering and Applied Sciences methodological tools were based on the documentation, Copy Right: Medwell Publications plans, photos and surveys. INTRODUCTION increase of around 6.4%. Concerning residential which represents 29% of the total energy consumption of the The building sector is considered as one of the most country, it constitutes an important potential deposit in dynamic sectors in Morocco, insofar as it creates wealth terms of rationalization of energy consumption and and employment and energizes the industrial and mining energy saving through the adoption of energy efficiency sectors. This sector plays a major role in the economic measures and the integration of renewable energies, and social development of the country with a contribution hence, the need to be part of an energy-saving approach. to the national GDP of almost 7% and to the employment Given the energy importance of the building sector of 9% of the active population. This is justified by the and in order to achieve its environmental objectives on a sustained pace of population growth and urbanization. national and international scale, notably those of the Paris Indeed, Morocco has an urbanization rate of 62%, thus agreement, the agenda of the Sustainable Development showing a remarkable increase in the urban population Goals (SDGs) and from the new Urban Agenda, Morocco and in households. has adopted an energy strategy, aiming at an energy In addition, the residential and tertiary building sector saving of12% by 2020 and 15% by 2030 from which the is the second most energy-intensive sector with 33% of residential sector will contribute 19% and the tertiary total energy consumption in Morocco and contributes to sector by 10%[1]. 11% of GHG emissions. In this sense, a legal arsenal has been put in place, The energy consumption of the building sector is namely law 47-09 relating to energy efficiency with the experiencing a significant acceleration due to the rapid aim of strengthening the energy performance levels of development of the housing stock, estimated at an constructions to be built or renovated, through the 2218 J. Eng. Applied Sci., 15 (10): 2218-2228, 2020 Building The study of thermal comfort is very important not only for the quality of the interior atmospheres but also for the quantity of energy to be provided by the Thermal Indoor air equipment (Fig. 1). Normative references of thermal comfort quality comfort[3]: C ISO 7730: Analytical determination and y s r g interpretation of thermal comfort by calculating the r e s e U En PMV and PPD indices and by local thermal comfort criteria C ISO 10551: Assessment of the influence of the Visual Acoustical comfort comfort thermal environment using subjective judgment scales C ASHRAE 55 standard: which defines comfort as a condition of mind which expresses satisfaction with Installation the thermal environment and is evaluated by a subjective evaluation Fig. 1: Design consistent with thermal comfort and energy efficiency Several evaluation methods and combinations have been developed by the researchers, based on experiments implementation of incentive measures to guarantee a carried out for the simultaneous manipulation of the better energy balance of buildings by climatic zones and variables of thermal comfort Among these methods, we law 13-09 relating to renewable energies which promotes can cite: the production of energy and the use of renewable energy sources in level of buildings and technical equipment. C Value of PMV and PPD Progress has been made with the aim of improving C Effective temperature resulting temperature thermal comfort and reducing the heating and air C Equatorial comfort index conditioning needs of buildings. This process was marked C Thermal stress index by the adoption of the Thermal Building Regulations in C Operating temperature Morocco (RTCM) which aims to produce a new C BRS method generation of constructions meeting minimum energy C Bioclimatic diagrams (Givoni, Olgyay, Mahoney, efficiency requirements according to climatic zones. This etc.) approach has been consolidated by the production of new standards in terms of sustainability and energy efficiency The ISO 7730 standard introduces two indices in buildings. for the evaluation of the thermal comfort of the occupants[4]: Thermal comfort: Thermal comfort is one of the The PMV (Predicted Mean Vote) index which components of what is called the “indoor environment”, represents the preference of individuals expressed as a the others are air quality, lighting and acoustics[2]. Thermal comfort is defined as a state of satisfaction function of the difference between the production of with regard to the thermal environment. It is a complex metabolic heat and the dissipation of heat in the room subjective concept that is highly interdisciplinary and under given temperature and clothing. It allows to predict involves various phenomena. Consequently, the the average vote of a group of people on a graduated scale evaluation methods are different depending on the aspects while expressing their thermal sensation. It is calculated we are interested in. as follows: Thermal comfort can be defined as a sensation produced by a system of physical, psychological, PMVe- 0.303.+0.028 ×Lexp -0.036. M physiological factors, leading the individual to express the well- being of his state. Thermal comfort can be The PPD: index of the Predicted Percentage of characterized in several ways: Dissatisfied (PPD) is an index which establishes a quantitative prediction of the percentage of dissatisfied C The absence of complaints for discomfort (Fanger) people thermally determined from the PMV. The PPD C Lack of general well-being index is expressed as a function of the relationship: C Conditions for which the body’s self-regulatory mechanisms are at a minimum level of activity 42 0.3353.PMV +0.2179PMV (Givoni) PPD 100.95e- 2219 J. Eng. Applied Sci., 15 (10): 2218-2228, 2020 h×T+h×T T ca rmr r h+hcr 50 40 Where: Probable T : Dry temperature measured by an ordinary heatstroke a 30 -1 thermometer placed in the shade C 1 m sec 0.4 m sec-1 T : Wall temperature or mean radiant temperature -1 mr DBT° 20 0.1 m sec hc : Convection transfer coefficient expressed in W/ 100-800 2 -2 m K 10 w m 2 hr : Radiation transfer coefficient expressed in W/ m 0 K 10 20 30 40 50 60 70 80 90 100 RH (%) (Olgyay, 1963) Thermal comfort in Morocco: Given the regional Fig. 2: Givoni diagram differences marked by the 6 climatic zones in Morocco, two strategies are to be adopted according to the needs: Bioclimatic analysis methods: Bioclimatic diagrams are tools for climate analysis and synthesis that allow C Winter comfort responds to the strategy of heat you to choose the main architectural options based which consists of capturing solar energy and storing it in the mass keep by insulation and distribute it in on the requirements of thermal comfort and climate the building profiles. C The comfort of summer responds to the cold strategy The principle consists in comparing on a single graph, which consists of protecting from the sun’s rays, “a polygon of comfort”, representing the external minimizing internal heat, dissipating excess heat and conditions and the area of thermal and hygrometric cooling naturally influence of certain architectural solutions or certain devices. This makes it possible to predict the human Application of the RTCM prescriptive approach: The comfort zone and to deduce the means of intervention by regulation adopts the use of two approaches: the architectural or technical devices which can restore the prescriptive approach and the performance approach. The zone of thermal satisfaction[5]. The diagram of Olgyay prescriptive approach consists of imposing a minimum Givoni: thickness of insulation on the walls, roof, floor and According to Givoni. B: “This method is based on a” glazing. Whereas the performance approach consists in bioclimatic diagram” showing the human comfort zone in relation to ambient air temperature and humidity, average verifying that the projected annual thermal transfers of the radiant temperature, wind speed, solar radiation and building are below a threshold defined by the regulations. evaporative heat loss”[6]. The demonstrator projects integrating the energy The method assumes that thermal comfort cannot be efficiency standards covered by the Thermal Construction estimated from the only parameter that is the air Regulations in Morocco (RTCM) were carried out as part temperature but involves several factors such as humidity of the National Program for Energy Efficiency in and air speed. Given the diversity of thermal comfort Buildings funded by the EU.