scholarly journals Performance Evaluation of External Light Shelves by Applying a Prism Sheet

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4618 ◽  
Author(s):  
Heangwoo Lee ◽  
Janghoo Seo
Keyword(s):  
Performance Evaluation ◽  
Energy Consumption ◽  
Economic Efficiency ◽  
Energy Savings ◽  
Building Energy ◽  
Full Scale ◽  
Natural Light ◽  
Building Sector ◽  
Sector Research ◽  
Lighting Energy

To address the increased use of lighting energy in the building sector, research on the use of light shelves has been increasing. Previous studies have focused on applying operating techniques to improve daylighting performance, which reduces the economic efficiency of light shelves and the building energy savings. This study proposes the use of prism sheets to improve the performance of light shelves, a concept which was validated by evaluating the performance related to saving building energy and improving indoor light uniformity through a full-scale testbed. This study used an external light shelf with no prism sheet, a window with a prism sheet applied, and a window with both an external light shelf and prism sheet applied as Case 1, Case 2, and Case 3, respectively, and analyzed the illuminance distribution and lighting energy consumption required to maintain the optimal indoor illumination for each case. This study also derived the optimal specifications for each case to save building energy and considered the flow of natural light to analyze the performance evaluation results. The main findings are as follows: (1) the optimal specifications to improve daylighting performance were derived for Case 1, requiring the application of operating techniques; (2) Case 2 was not suitable for saving energy and improving light uniformity when compared to Case 1; and (3) Case 3 was effective in saving building energy. In Case 3, even when the light shelf was fixed at 20° without moving, it saved building energy and improved light uniformity compared to Case 1. However, the prism sheet in Case 3 should be detached during winter to maximize building energy savings.

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.

Energy savings potential of new aeration system: Full scale trials

2012 ◽  
Vol 7 (4) ◽  
Author(s):  
A. Lazić ◽  
V. Larsson ◽  
Å. Nordenborg
Keyword(s):  
Control System ◽  
Energy Consumption ◽  
Total Energy ◽  
Energy Savings ◽  
Treatment Plant ◽  
Full Scale ◽  
Total Energy Consumption ◽  
Aeration System ◽  
Fine Bubble ◽  
Aeration Control

The objective of this work is to decrease energy consumption of the aeration system at a mid-size conventional wastewater treatment plant in the south of Sweden where aeration consumes 44% of the total energy consumption of the plant. By designing an energy optimised aeration system (with aeration grids, blowers, controlling valves) and then operating it with a new aeration control system (dissolved oxygen cascade control and most open valve logic) one can save energy. The concept has been tested in full scale by comparing two treatment lines: a reference line (consisting of old fine bubble tube diffusers, old lobe blowers, simple DO control) with a test line (consisting of new Sanitaire Silver Series Low Pressure fine bubble diffusers, a new screw blower and the Flygt aeration control system). Energy savings with the new aeration system measured as Aeration Efficiency was 65%. Furthermore, 13% of the total energy consumption of the whole plant, or 21 000 €/year, could be saved when the tested line was operated with the new aeration system.

scholarly journals The Impact Assessment of Climate Change on Building Energy Consumption in Poland

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4084
Author(s):  
Hassan Bazazzadeh ◽  
Peiman Pilechiha ◽  
Adam Nadolny ◽  
Mohammadjavad Mahdavinejad ◽  
Seyedeh sara Hashemi safaei
Keyword(s):  
Climate Change ◽  
Energy Consumption ◽  
Thermal Load ◽  
Building Energy ◽  
Building Energy Consumption ◽  
Building Sector ◽  
Energy Demands ◽  
Heating Load ◽  
The Impact ◽  
The City

A substantial share of the building sector in global energy demand has attracted scholars to focus on the energy efficiency of the building sector. The building’s energy consumption has been projected to increase due to mass urbanization, high living comfort standards, and, more importantly, climate change. While climate change has potential impacts on the rate of energy consumption in buildings, several studies have shown that these impacts differ from one region to another. In response, this paper aimed to investigate the impact of climate change on the heating and cooling energy demands of buildings as influential variables in building energy consumption in the city of Poznan, Poland. In this sense, through the statistical downscaling method and considering the most recent Typical Meteorological Year (2004–2018) as the baseline, the future weather data for 2050 and 2080 of the city of Poznan were produced according to the HadCM3 and A2 GHG scenario. These generated files were then used to simulate the energy demands in 16 building prototypes of the ASHRAE 90.1 standard. The results indicate an average increase in cooling load and a decrease in heating load at 135% and 40% , respectively, by 2080. Due to the higher share of heating load, the total thermal load of the buildings decreased within the study period. Therefore, while the total thermal load is currently under the decrease, to avoid its rise in the future, serious measures should be taken to control the increased cooling demand and, consequently, thermal load and GHG emissions.

scholarly journals Development of Window-Mounted Air Cap Roller Module

2018 ◽  
Author(s):  
Heangwoo Lee ◽  
Janghoo Seo
Keyword(s):  
Energy Consumption ◽  
Indoor Environment ◽  
Building Energy ◽  
Building Energy Consumption ◽  
Test Bed ◽  
Lighting Energy ◽  
Scale Test ◽  
And Performance ◽  
Indoor Lighting ◽  
Indoor And Outdoor

While previous research has shown the use of attachable air-caps on windows to efficiently reduce a building’s energy consumption, the air-caps considered had to be attached to the entire window’s surface, thus limiting the occupants’ view and creating the inconvenience of needing to detach and attach the air-caps. In this study, a window-mounted air-cap roller module using Velcro tape that may be easily attached, detached, and rolled up or down was developed and performance tested in a full-scale test bed. It was found that as the area of the air-caps attached on a window increased, the required indoor lighting energy increased. However, the window insulation improved, thus reducing the cooling and heating energy needed. Attaching the air-caps to the entire window surface effectively reduced the building’s energy consumption, but views through the window may be disturbed. Thus, the developed window-mounted air-caps enable an occupant to reduce the building energy consumption and maintain their view according to their need. The findings of this study may contribute to a reduction in building energy consumption without sacrificing a pleasant indoor environment. Further studies may be needed to verify their efficacy under varying indoor and outdoor conditions.

scholarly journals An Ontology-Based Framework for Building Energy Management with IoT

Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 485 ◽  
Author(s):  
Clement Lork ◽  
Vishal Choudhary ◽  
Naveed Ul Hassan ◽  
Wayes Tushar ◽  
Chau Yuen ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Management ◽  
Management System ◽  
Energy Savings ◽  
Environmental Parameters ◽  
Building Energy ◽  
Building Energy Efficiency ◽  
Commercial Building ◽  
Building Energy Management ◽  
Building Management

In this paper, we develop an ontology-based framework for energy management in buildings. We divide the functional architecture of a building energy management system into three interconnected modules that include building management system (BMS), benchmarking (BMK), and evaluation & control (ENC) modules. The BMS module is responsible for measuring several useful environmental parameters, as well as real-time energy consumption of the building. The BMK module provides the necessary information required to understand the context and cause of building energy efficiency or inefficiency, and also the information which can further differentiate normal and abnormal energy consumption in different scenarios. The ENC module evaluates all the information coming from BMS and BMK modules, the information is contextualized, and finally the cause of energy inefficiency/abnormality and mitigating control actions are determined. Methodology to design appropriate ontology and inference rules for various modules is also discussed. With the help of actual data obtained from three different rooms in a commercial building in Singapore, a case study is developed to demonstrate the application and advantages of the proposed framework. By mitigating the appropriate cause of abnormal inefficiency, we can achieve 5.7%, 11.8% and 8.7% energy savings in Room 1, Room 2, and Room 3 respectively, while creating minimum inconvenience for the users.

scholarly journals Scenario Analysis for GHG Emission Reduction Potential of the Building Sector for New City in South Korea

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5514
Author(s):  
Seo-Hoon Kim ◽  
SungJin Lee ◽  
Seol-Yee Han ◽  
Jong-Hun Kim
Keyword(s):  
Climate Change ◽  
Energy Consumption ◽  
South Korea ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Building Energy ◽  
Building Sector ◽  
Ghg Reduction ◽  
New City

A new government report on climate change shows that global emissions of greenhouse gases have increased to very high levels despite various policies to reduce climate change. Building energy accounts for 40% of the world’s energy consumption and accounts for 33% of the world’s greenhouse gas emissions. This study applied the LEAP (Long-range energy alternatives planning) model and Bass diffusion method for predicting the total energy consumption and GHG (Greenhouse Gas) emissions from the residential and commercial building sector of Sejong City in South Korea. Then, using the Bass diffusion model, three scenarios were analyzed (REST: Renewable energy supply target, BES: Building energy saving, BEP: Building energy policy) for GHG reduction. The GHG emissions for Sejong City for 2015–2030 were analyzed, and the past and future GHG emissions of the city were predicted in a Business-as-Usual (BAU) scenario. In the REST scenario, the GHG emissions would attain a 24.5% reduction and, in the BES scenario, the GHG emissions would attain 12.81% reduction by 2030. Finally, the BEP scenario shows the potential for a 19.81% GHG reduction. These results could be used to guide the planning and development of the new city.

scholarly journals Dilution effect of the building area on energy intensity in urban residential buildings

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jingxin Gao ◽  
Xiaoyang Zhong ◽  
Weiguang Cai ◽  
Hong Ren ◽  
Tengfei Huo ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Intensity ◽  
Energy Savings ◽  
Residential Buildings ◽  
Dilution Effect ◽  
Building Energy ◽  
Residential Energy ◽  
Stirpat Model ◽  
Building Area ◽  
Consumption Energy

Abstract Urban residential buildings make large contributions to energy consumption. Energy consumption per square meter is most widely used to measure energy efficiency in urban residential buildings. This study aims to explore whether it is an appropriate indicator. An extended STIRPAT model was used based on the survey data from 867 households. Here we present that building area per household has a dilution effect on energy consumption per square meter. Neglecting this dilution effect leads to a significant overestimation of the effectiveness of building energy savings standards. Further analysis suggests that the peak of energy consumption per square meter in China’s urban residential buildings occurred in 2012 when accounting for the dilution effect, which is 11 years later than it would have occurred without considering the dilution effect. Overall, overlooking the dilution effect may lead to misleading judgments of crucial energy-saving policy tools, as well as the ongoing trend of residential energy consumption in China.

scholarly journals A Basic Study on the Performance Evaluation of a Movable Light Shelf with a Rolling Reflector That Can Change Reflectivity to Improve the Visual Environment

2020 ◽  
Vol 17 (22) ◽  
pp. 8338
Author(s):  
Heangwoo Lee
Keyword(s):  
Performance Evaluation ◽  
Energy Use ◽  
Energy Savings ◽  
Luminance Contrast ◽  
Visual Environment ◽  
Basic Study ◽  
Lighting Energy ◽  
Save Energy ◽  
Indoor Spaces ◽  
A Performance

In recent years, the need for comfortable visual environments in indoor spaces has increased energy use in buildings. There have been diverse studies on using a light shelf to solve this problem. It is an effective system that allows external natural light deep into indoor spaces through reflection. However, prior studies have used light shelves with a fixed reflectivity, and there are few studies on improving the visual environment through light shelf control. Therefore, this study proposes a movable light shelf with a rolling reflector that can change the reflectivity. To achieve these objectives, we conducted a performance evaluation of the system’s ability to save energy and improve the visual environment. This study built a real scale testbed and conducted a performance evaluation by deriving values for lighting energy consumption, uniformity, and luminance contrast depending on the light shelf variables. We conclude that (1) the light shelf system achieved an energy savings of 13.6% and 5.7%, respectively, compared to a fixed type light shelf, whose reflectivity cannot be changed, and a traditional movable light shelf; (2) in terms of improving the visual environment, results suggest that the visual environment could be improved using a light shelf by deriving light shelf variables that disturb indoor uniformity; and (3) the results verified glare generation conditions by deriving luminance contrast caused by the variables of light shelf angle and its reflectivity.

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.

Sign in / Sign up

Export Citation Format

Share Document