scholarly journals Integrating Daylighting with Task-Ambient Lighting for Enhanced Energy Savings in Office Spaces

2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Simeon Nyambaka Ingabo ◽  
Pipat Chaiwiwatworakul
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Fundamental Aspect ◽  
Free Standing ◽  
Ambient Lighting ◽  
Lighting Energy ◽  
Task Lighting ◽  
Shading Devices

Daylighting has been widely studied as a fundamental aspect of spatial illumination and energy efficient façade design. Effective installation and control of shading devices diminishes the adverse effects of prevailing climatic conditions on building envelope performance and reduces resultant lighting and cooling energy consumption. Task-ambient lighting as a free-standing approach has also been proven to reduce lighting energy consumption compared with typical general ambient lighting. This study estimates the energy saving potential of integrating daylighting through fixed external horizontal shading slats with task lighting. Spot measurements were taken in a test room to validate a daylight calculation program. Full year indoor work plane daylight simulations were performed for office spaces of different floor areas and varying window to wall ratios. Indoor daylight quality was assessed using the Useful Daylight Illuminance metric and three different task lighting schemes explored.  Lighting energy savings of 10% to 90% were estimated under the three schemes in comparison to similar office spaces with common unshaded heat reflective glazing.

Evaluation of impact of passive design measures with energy saving potential through estimation of shading control for visual comfort

2017 ◽  
Vol 42 (3) ◽  
pp. 220-238 ◽  
Author(s):  
Lakshya Sharma ◽  
K Kishan Lal ◽  
Dibakar Rakshit
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Climatic Conditions ◽  
Design Parameters ◽  
Visual Comfort ◽  
Passive Design ◽  
Lighting Energy ◽  
Insulation Thickness ◽  
Heating Loads ◽  
Cooling Loads

Residential and commercial buildings together account for one-third of world’s final energy consumption, thus making energy management in buildings of considerable significance. Passive design concept that depends on climate and location can be used as an effective and economical method to reduce the energy consumption in buildings. Seven cities in India, each representative of different geographic and climatic conditions, were selected for analysis. This article studies how the peak cooling and heating load are affected by varying some of the passive design parameters for each of the seven cities. The parameters varied are wall insulation thickness, roof insulation thickness, overhang depth, window orientation, and window-to-wall ratio. Results show that optimized passive design could reduce the peak cooling and heating loads by about 50%. Shading reduces cooling loads but is found to increase heating loads. In some of the locations, both heating in winter and cooling in summer are needed and designers should adopt appropriate passive measures depending on the location. Also for the same building, evaluation of shading is done in the context of lighting energy savings. An algorithm has been developed to iteratively alter and analyze set of roller blind positions to maintain visual comfort; as a result, the corresponding potential annual energy savings due to lighting were estimated. It was also observed that even after providing visual comfort to the occupants, energy savings only reduced by approximately 1% as compared to the case when visual comfort was overlooked.

Impact of roof shading on building energy performance in warm & humid climatic places of India

2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Energy Performance ◽  
General Assumption ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Passive Cooling ◽  
Base Case ◽  
U Value ◽  
The Impact

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.

scholarly journals Determination of Optimum Envelope of Religious Buildings in Terms of Thermal Comfort and Energy Consumption: Mosque Cases

Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6597
Author(s):  
Ahmet Bircan Atmaca ◽  
Gülay Zorer Gedik ◽  
Andreas Wagner
Keyword(s):  
Thermal Properties ◽  
Energy Consumption ◽  
Thermal Comfort ◽  
Thermal Insulation ◽  
Energy Savings ◽  
Gain Factor ◽  
Building Envelope ◽  
Comfort Level ◽  
Humid Climate ◽  
Savings Rate

Mosques are quite different from other building types in terms of occupant type and usage schedule. For this reason, they should be evaluated differently from other building types in terms of thermal comfort and energy consumption. It is difficult and probably not even necessary to create homogeneous thermal comfort in mosques’ entire usage area, which has large volumes and various areas for different activities. Nevertheless, energy consumption should be at a minimum level. In order to ensure that mosques are minimally affected by outdoor climatic changes, the improvement of the properties of the building envelope should have the highest priority. These optimal properties of the building envelope have to be in line with thermal comfort in mosques. The proposed method will be a guide for designers and occupants in the design process of new mosques or the use of existing mosques. The effect of the thermal properties of the building envelope on energy consumption was investigated to ensure optimum energy consumption together with an acceptable thermal comfort level. For this purpose, a parametric simulation study of the mosques was conducted by varying optical and thermal properties of the building envelope for a temperature humid climate zone. The simulation results were analyzed and evaluated according to current standards, and an appropriate envelope was determined. The results show that thermal insulation improvements in the roof dome of buildings with a large volume contributed more to energy savings than in walls and foundations. The use of double or triple glazing in transparent areas is an issue that should be considered together with the solar energy gain factor. Additionally, an increasing thickness of thermal insulation in the building envelope contributed positively to energy savings. However, the energy savings rate decreased after a certain thickness. The proposed building envelope achieved a 33% energy savings compared to the base scenario.

Effect of the Window Position in the Building Envelope on Energy Consumption

2018 ◽  
Vol 7 (3) ◽  
pp. 1861
Author(s):  
Neveen Y. Azmy ◽  
Rania E. Ashmawy
Keyword(s):  
Energy Consumption ◽  
Light Intensity ◽  
Environmental Performance ◽  
Lower Energy ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Natural Lighting ◽  
Energy Plus ◽  
Window Position

Windows play a significant role as they largely influence the energy load. Although there are many studies on the energy-efficient windows design, there is still a lack in information about the mutual impact of windows’ size, position and orientation on the energy loads. In this paper, the effect of different window positions and orientations on the energy consumption in a typical room in an administrative building that is located in the hot climatic conditions of Cairo city, Egypt is considered. This case study has been modeled and analyzed to achieve good environmental performance for architectural space, as well as assessing its impact on the amount of natural lighting required by using the Energy Plus program. The study concludes that the WWR (Window Wall Ratio) 20% square north-oriented upper  opening consumes 25% lower energy than the rectangular 3:1 opening in the lower west-oriented façade. The upper openings are the highest in terms of light intensity, as they cover about 50% of the room area. The WWR 30% rectangular north-oriented upper 3:1 opening consumes 29% lower energy than the rectangular lower 3:1opening in the façade. Regarding light intensity, the upper openings are the best for natural lighting as the light covers more than 60% of the room area.                                                                                                                                                               

Study on movable light-shelf system with location-awareness technology for lighting energy saving

2016 ◽  
Vol 26 (6) ◽  
pp. 796-812 ◽  
Author(s):  
Heangwoo Lee ◽  
Sang-hoon Gim ◽  
Janghoo Seo ◽  
Yongseong Kim
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Energy Savings ◽  
Full Scale ◽  
Location Awareness ◽  
Energy Saving Potential ◽  
Recent Increase ◽  
Lighting Energy ◽  
External Conditions ◽  
Incoming Light

Various ongoing studies regard light-shelves as one solution to the recent increase in lighting energy consumption. However, in previous light-shelf systems, the direction of incoming light was determined by external conditions, thereby limiting the efficiency of lighting energy saving. The purpose of the present study was to develop a movable light-shelf system with location-awareness technology and verify its performance. In this study, a full-scale testbed was established in order to test the proposed movable light-shelf system with location awareness as well as to verify its energy saving potential. The results were analysed and compared with the performances of previous fixed (Case 1) and movable (Case 2) light-shelf systems without location-awareness technology. The obtained results were as follows. (1) The proposed light-shelf system can respond to external conditions and to the location of the occupant by means of the control axis of the light-shelf module angle through modulation between the control axis of the angle of the previous light-shelf and the reflector of the light-shelf. (2) The proposed light-shelf system provides 90.0% and 86.6%/91.0% energy savings in comparison to Case 1 and Case 2, respectively.

scholarly journals A Comparative Study: Energy Performance Analysis of Conventional Office Buildings at Lucknow

2020 ◽  
Vol 20 (1) ◽  
pp. 24-34
Author(s):  
Farheen Bano ◽  
Vandana Sehgal
Keyword(s):  
Energy Consumption ◽  
Time Use ◽  
Energy Savings ◽  
Energy Performance ◽  
Building Envelope ◽  
Office Buildings ◽  
Energy Audit ◽  
Energy Usage ◽  
Factors Affecting ◽  
Using Data

In this study, the energy consumption of three government and three private office buildings in Lucknow was investigated, and the energy performance index (EPI) for each building was determined. The main purpose of this research was to assess the energy usage of the buildings and identify factors affecting the energy usage. An analysis was performed using data from an energy audit of government buildings, electricity bills of private office buildings, and an on-site visit to determine building envelope materials and its systems. The annual energy consumption of buildings has been evaluated through EPI. The EPI, measured in kilowatt hour per square meter per year, is annual energy consumption in kilowatt hours divided by the gross floor area of the building in square meters. In this study, the energy benchmark for day-time-use office buildings in composite climate specified by Energy Conservation Building Code (ECBC) has been compared with the energy consumption of the selected buildings. Consequently, it has been found that the average EPI of the selected buildings was close to the national energy benchmark indicated by ECBC. Moreover, factors causing inefficient energy consumption were determined, and solutions for consistent energy savings are suggested for buildings in composite climate.

scholarly journals Improvement of energy performances of existing buildings by application of solar thermal systems

Spatium ◽  
2009 ◽  
pp. 19-22 ◽  
Author(s):  
Aleksandra Krstic-Furundzic ◽  
Vesna Kosoric
Keyword(s):  
Energy Savings ◽  
Residential Buildings ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Solar Thermal ◽  
Existing Buildings ◽  
Thermal Systems ◽  
Climate Conditions ◽  
Solar Thermal Collectors ◽  
Reduction Of Co2

Improvement of energy performances of the existing buildings in the suburban settlement Konjarnik in Belgrade, by the application of solar thermal systems is the topic presented in this paper. Hypothetical models of building improvements are created to allow the benefits of applying solar thermal collectors to residential buildings in Belgrade climate conditions to be estimated. This case study presents different design variants of solar thermal collectors integrated into a multifamily building envelope. The following aspects of solar thermal systems integration are analyzed in the paper: energy, architectural, ecological and economic. The results show that in Belgrade climatic conditions significant energy savings and reduction of CO2 emissions can be obtained with the application of solar thermal collectors.

scholarly journals The impact of building envelope retrofit measures on postwar MURBS in Toronto

2021 ◽  
Author(s):  
Sara Damyar
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Energy Use ◽  
Energy Savings ◽  
Building Envelope ◽  
Simulation Software ◽  
Energy Simulation ◽  
Reduce Energy Consumption ◽  
The Impact ◽  
Current Standards

Building envelope retrofits is one of the options available to reduce energy consumption of postwar MURBs in Toronto. This study evaluates the impact of building envelope retrofits that meet current standards on energy consumption of a Toronto postwar MURB; utilizing eQUEST energy simulation software. Further upgrades also take place to evaluate how the impact of building envelope retrofits on energy use can be increased and optimized for all assemblies of building envelope and airtightness. Moreover, the retrofit strategies are ranked based on cost and energy-saving effectiveness. The results of the analysis reveal that building envelope retrofit based on OBC-2012 standards can reduce the energy consumption by up to 44%. Furthermore, the optimal RSI values of all building envelope components were found to be equal or less than code requirements which outcomes significant energy savings. Lastly, the ranking of the strategies helps to identify the best option according to the priorities of a project.

scholarly journals Energy Efficiency of Novel Interior Surface Layer with Improved Thermal Characteristics and Its Effect on Hygrothermal Performance of Contemporary Building Envelopes

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 2012 ◽  
Author(s):  
Jan Fořt ◽  
Jiří Šál ◽  
Jan Kočí ◽  
Robert Černý
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Computational Simulation ◽  
Thermal Characteristics ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Heat Fluxes ◽  
Passive Cooling ◽  
Fuel Price ◽  
Climate Conditions

Facing the consequences of climate change and fuel price rises, the achievement of the requirements for low-energy consumption of buildings has become a challenging issue. On top of that, increased demands on indoor hygrothermal conditions usually require the utilization of additional heating, ventilation, and air-conditioning (HVAC) systems to maintain a comfortable environment. On this account, several advanced and modern materials are widely investigated as a promising way for reduction of the buildings’ energy consumption including utilization of passive heating/cooling energy. However, the efficiency and suitability of passive strategies depending on several aspects including the influence of location, exterior climatic conditions, load-bearing materials used, and insulation materials applied. The main objective of this study consists of the investigation of the energy performance benefits gained by the utilization of advanced materials in plasters by computational modeling. Results obtained from a computational simulation reveal the capability of the studied passive cooling/heating methods on the moderation of indoor air quality together with the reduction of the diurnal temperature fluctuation. Achieved results disclose differences in terms of energy savings for even small variation in outdoor climate conditions. Additionally, the effectivity of passive cooling/heating alters considerably during the summer and winter periods. Based on the analysis of simulated heat fluxes, the potential energy savings related to improved thermal properties of the applied plaster layer reached up to 12.08% and thus represent an interesting passive solution towards energy sustainability to meet the criteria on modern buildings.

Interpretation and Analysis About Energy Savings in Commercial Green Houses Using Custom-Made Shadenets As Well As Thermal Reflective Screens

2017 ◽  
Author(s):  
Subin MattaraChalill ◽  
Chinnapalaniandi Periasamy ◽  
Pillai Nandakumar ◽  
Ram Karthikeyan
Keyword(s):  
Energy Consumption ◽  
Plant Growth ◽  
Temperature Control ◽  
Large Scale ◽  
Energy Savings ◽  
Microstructural Analysis ◽  
Climatic Conditions ◽  
Operational Cost ◽  
Active Radiation ◽  
Selection Of

Greenhouses are known to be the modern outlook for the agronomical industry in terms of high-end yield especially in the regions where climatic conditions are not stable like in the Middle East, Europe, and United States. Crop optimization is one of the major challenges facing the farmers and the controlled production centers can dictate this difficulty in the upcoming market. Greenhouses are considered as the high -tech production centers which can support the food industry to have a green revolution through the mass production of the vegetables and spices. Properly designed commercial greenhouses can increase the yield by minimizing the operational cost especially in terms of reducing the energy consumption. In order to have a properly designed greenhouse, the selection or up gradation of the shade structures can play a vital role. Conventional greenhouses are made of polycarbonate sheets and in some cases the polyhouses by using simple polyethylene sheets. In this scenario, the main drawbacks were the energy consumption, operational expenses and the effectiveness of the indoor temperature control. Custom designed shades based on the crop requirements can provide high production rate by reducing the energy consumption. The detailed microstructural analysis in conjunction with the photosynthesis demand can provide a better selection of the shade-net or curtains. Greenhouse shade structure can be upgraded using the motorized specially designed nets or by using thermal-reflective screens. This up gradation can provide four stage advantages. In stage one this can decrease the 50% of heat energy and which will save the HVAC operational cost. During the stage, two better temperature control during the day and night will provide a good environment to provide proper PAR (Photosynthetically Active Radiation)[5] for photosynthesis, in the wavelength range of 400 to 700 nanometer. Third and fourth stages are the protection from the frost as well heat stress during the different climatic conditions. In the present market condition, the commercial greenhouses are being built in large scale by neglecting the energy saving options in shade structures. The commercial greenhouses using the upgraded shade structures can save the operational cost by 25 to 30%. Selection of this shade-nets or curtains can be done using the detailed microstructural analysis of the material. Shade-nets/curtains can be controlled manually, mechanically or can be automated in large-scale greenhouses. Flowering dates in the plants can be accelerated using the shading materials and delayed by the use of control treatment, which coincides with the results obtained in the previous studies [1]. This has proven with high land experiments [2]. Greenhouse shade nets are used in order to protect crops and plants from adverse weather conditions, animals and pests, besides providing suitable conditions for plant growth. The essential performance properties required for greenhouse shade nets are the resistance to solar radiation and weathering. The intensity of the Photo Synthetically Active Radiation (PAR) directly influences plant growth. Other nonvisible radiations are ultraviolet (UV), infrared (IR) and far infrared (FIR)[16]. Polypropylene and polyester are more resistant to UV radiation than polyethylene, which is resistant to radiations in the visible region. The use of greenhouse shade nets in outdoor conditions also requires them to be resistant to abrasion[3]. The objective of the present work is to examine the effectiveness of the properly selected shade-net/curtain in commercial greenhouses in terms of high yield energy savings. This study was conducted to compare the traditional polycarbonate sheet with the innovation of properly designed shade curtain made-up from high-density polyethylene (HDPE) fiber reinforced material discover the best shading method for plant growth in an ideal energy conservation scenario. The study was conducted in the two identical greenhouses (planted with lettuce crop) located in Al Khawaneej farm in the Emirate of Dubai in the United Arab Emirates. Yield versus the energy consumption has been observed in a period of time and obtained the reduction in energy consummation of almost 20 to 30 %.

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