Influence of the Advancement in the LED Lighting Technologies on the Optimum Windows-to-Wall Ratio of Jordanians Residential Buildings

Abstract

Based on recent developments and the predicted future advancement of lighting technologies, researchers are now questioning the extent to which daylight is effective in lowering the overall energy consumption of buildings. As light-emitting diode (LED) luminaires are highly energy efficient, the amount of power consumed for lighting purposes can be reduced, even in situations where the lighting system is at its full power. It has already been demonstrated that LED-lighting technologies can facilitate significant energy savings through minimizing window size (the main source of heat loss in buildings), and there is considerable potential for developing the LEDs’ source efficacy and lighting-product efficiency to ultimately achieve levels of efficacy of approximately 350 lumens per Watt (lm/W). For building designs to be sustainable in the future, it is critical that the windows-to-wall ratio (WWR) is optimized to minimize both heating and cooling loads, as well as the total energy consumed by the building for lighting, according to the efficiency of the LED, while still maintaining a suitable lighting level for occupants. This research examines the influence of the WWR on the total amount of energy consumed by standard buildings in Jordan using various LED luminaires (existing and projected efficiencies). DesignBuilder software was utilized to analyze the effect of LED-technology development on optimizing the WWR for a typical residential structure in Jordan. The research presents beneficial recommendations with respect to optimizing the WWR for primary decision-makers in the design of residential buildings with enhanced energy efficiency, considering the losses and gains associated with solar heat and light to capitalize on solar energy with no adverse impacts by windows size. The outcomes suggest a WWR of 17% could be achieved by typical residential buildings in Jordan that have extremely efficient LED lighting systems (350 lm/W), which is more than 50% less than the existing level of 40% recommended by multiple standards. Additionally, this study highlighted that when the efficiency of LED technologies increases, the energy demand of the building will be reduced because of lower energy usage combined with heat gain resulting from the LED efficiency.

Critical Review on the Energy Retrofitting Trends in Residential Buildings of Arab Mashreq and Maghreb Countries

“…The final screening process yielded 41 relevant studies in the AMM countries, with 32 studies found in Mashreq countries and 9 in Maghreb countries, as shown in Figure 7. In the Mashreq countries, there were 18 studies in Jordan [64,65,[69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84], 9 in Egypt [85][86][87][88][89][90][91][92][93][94], 2 in Palestine [95,96], 2 in Iraq [97,98], 1 in Lebanon [99], and no study was presented for Syria. In the Maghreb countries, there were 5 studies in Algeria [100][101][102][103][104], 3 in Morocco [105][106][107], 1 in Tunisia [67], and no study was presented for Libya.…”

Development of a Linear Regression Model Based on the Most Influential Predictors for a Research Office Cooling Load

“…The contribution of solar irradiance through the wall is much smaller compared to the window; at the same time, the solar light can be used to light the room. The windowsto-wall ratio should be optimised to minimise both heating and cooling loads, as well as the total energy consumed by lighting while maintaining a suitable lighting level for occupants [35]. The work hour variable is also an important predictor because it deals with daily work schedules, but it is substantially connected with NoM and NoF.…”

Evaluating and Enhancing the Energy Efficiency of Representative Residential Buildings by Applying National and International Standards Using BIM

“…In terms of local research, on the one hand, numerous studies have been conducted to investigate energy consumption for both new and existing residential buildings in Jordan, such as [18,[37][38][39][40][41][42][43][44][45]. However, most of these studies focused on improving indoor comfort levels and increasing the energy efficiency in residential buildings.…”