The potential of simplified concepts for daylight harvesting

2005 ◽  
Vol 37 (1) ◽  
pp. 21-38 ◽  
Author(s):  
RP Leslie ◽  
R Raghavan ◽  
O Howlett ◽  
C Eaton
Keyword(s):  
New York ◽  
Energy Consumption ◽  
Potential Energy ◽  
Energy Saving ◽  
Solar Irradiance ◽  
Energy Savings ◽  
Climatic Regions ◽  
Switching Behaviour ◽  
Open Plan ◽  
Daylight Harvesting

Daylighting systems offer tremendous potential for reducing the energy consumption of electric lighting, but their usage has been inhibited by high costs and imperfect performance of current technologies. This paper presents predictions of energy savings for two proposed daylighting technologies, a daylight-sensing switch and an automatic blinds system, which employ simple, inexpensive components and designs. Assumptions of solar irradiance, blind position, blind operation behaviour, and light switching behaviour were combined with illuminance data and daylight factors to develop an algorithm for calculating the potential energy usages of six different systems in commercial private offices and open plan offices. Results show that the combined usage of the proposed technologies perform with an average annual energy saving of 24% compared with manual switching and blinds operation in Albany, New York. Compared with a photosensor-operated dimming system, the proposed technologies combined show better performance during summer months. Comparisons were also made for the systems in six US climatic regions.

Modelling energy consumption behaviour using “energy culture” concept for student accommodations in Malaysian public universities

Facilities ◽  
2017 ◽  
Vol 35 (11/12) ◽  
pp. 658-683 ◽  
Author(s):  
Mohd Hafizal Ishak
Keyword(s):  
Energy Consumption ◽  
Potential Energy ◽  
Energy Saving ◽  
Public Universities ◽  
Energy Savings ◽  
Environmental Concern ◽  
Content Type ◽  
Consumption Behaviour ◽  
Potential Energy Saving ◽  
To Come

Purpose In working towards a sustainable campus of public universities, energy consumption behaviour assessment is one of the several issues that requires attention by the facilities manager. Information on energy consumption behaviour is needed to determine potential energy savings. The purpose of this study is to assess energy consumption behaviour for student accommodations in Malaysian public universities. Design/methodology/approach This study focuses on developing energy consumption behaviour models (ECBMs) and assesses the potential energy savings. The “energy culture” framework consolidated with multiple regression analysis is used to strengthen the development of ECBMs. A self-administrated survey involving 1,009 respondents in selected public universities was carried out. Findings The result shows that five factors from the energy culture framework contribute to energy consumption behaviour, namely, building regulation, environmental concern, education, social marketing and direct factors (device and activities). These factors are included in the model for predicting energy consumption levels. The results show that there is a 78 per cent difference in energy consumption between the observed and predicted data. Practical implications This study indicates a high potential energy saving among students of Malaysian public universities. Originality/value The model was tested against the overall students among Malaysian public universities. In future, the model can be tested within hostel accommodations. The present assessment revealed the potential energy saving among the hostel buildings and sets the target regarding which building has a potential to reduce energy. It also helps the facilities managers to come up with strategies for programmes and energy policy in public universities.

Evaluation methods of the daylight performance and potential energy saving of tubular daylight guide systems: A review

2021 ◽  
pp. 1420326X2199241
Author(s):  
Hanlin Li ◽  
Dan Wu ◽  
Yanping Yuan ◽  
Lijun Zuo
Keyword(s):  
Potential Energy ◽  
Energy Saving ◽  
Energy Savings ◽  
Performance Metrics ◽  
Field Measurements ◽  
Building Design ◽  
Estimation Methods ◽  
The Past ◽  
Potential Energy Saving ◽  
Daylight Performance

In the past 30 years, tubular daylight guide systems (TDGSs) have become one of the most popular ways to transport outdoor natural light into the inner space in building design. However, tubular daylight guide systems are not widely used because of the lack of methods to evaluate methods on the suitability of the TDGSs. This study therefore summarizes the daylight performance metrics of TDGSs and presents the estimation methods in terms of field measurements, simulation and empirical formulae. This study focuses on the daylight performance and potential energy savings of TDGSs. Moreover, this study will be helpful for building designers to build healthy, comfortable and energy-saving indoor environment.

Comparison of Energy-Saving Driving Style Strategies

2016 ◽  
Author(s):  
Yigit Fidansoy ◽  
Sohejl Wanjani ◽  
Sebastian Schmidt
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Fossil Fuels ◽  
Design Thinking ◽  
Energy Savings ◽  
Driving Style ◽  
Advisory Systems ◽  
Train Dynamics ◽  
Input Variables ◽  
And Training

Due to the increasing scarcity of fossil fuels and the climate change, the importance of energy efficiency is increasing. This importance is major especially in areas where the energy consumption is high. Rail transport depicts such an area. The highest proportion of energy consumed in the railway is the so called traction energy. This energy is required for the train run. In the timetable, allowances leave a margin for the driving style of train run. By the selective use of strategies that change the driving style, it is possible to exploit these allowances and reduce the traction energy consumption. The first objective of this study deals with the development of algorithms for energy-saving driving style. First, the necessary input variables of the algorithms based on the literature research and the formulas of train dynamics were determined. Then the algorithms were developed to create different energy-saving driving styles, resulting choose the best result which should be shown as a driving recommendation. The developed algorithms were used in an application example in order to calculate the potential of energy-savings. The example should represent the influence of the input variables for a comparison of different situations. At last the acceptance of the determined driving strategies in practice was investigated. By implementing the design thinking method it was identified that driver advisory systems and training programs are necessary to facilitate energy-saving driving in practice.

scholarly journals Field Study Of A Radiant Heating System For Sleep Thermal Comfort And Potential Energy Saving

2021 ◽  
Author(s):  
Christopher L. K. Wang
Keyword(s):  
Potential Energy ◽  
Thermal Comfort ◽  
Energy Saving ◽  
Energy Savings ◽  
Thermal Environment ◽  
Residential Buildings ◽  
Thermal Conditions ◽  
Heating System ◽  
The Body ◽  
Radiant Temperature

As sleep is unconscious, the traditional definition of thermal comfort with conscious judgment does not apply. In this thesis sleep thermal comfort is defined as the thermal condition which enables sleep to most efficiently rejuvenate the body and mind. A comfort model was developed to stimulate the respective thermal environment required to achieve the desired body thermal conditions and a new infrared sphere method was developed to measure mean radiant temperature. Existing heating conditions according to building code conditions during sleeping hours was calculated to likely overheat a sleeping person and allowed energy saving potential by reducing nighttime heating set points. Experimenting with existing radiantly and forced air heated residential buildings, it was confirmed that thermal environment was too hot for comfortable sleep and that the infrared sphere method shows promise. With the site data, potential energy savings were calculated and around 10% of energy consumption reduction may be achieved during peak heating.

Improving Ships’ Efficiency Using Energy Saving Devices (ESDs)

2015 ◽  
Author(s):  
Charinda L. Perera ◽  
Ema Muk-Pavic
Keyword(s):  
Boundary Layer ◽  
Potential Energy ◽  
Energy Saving ◽  
Flow Pattern ◽  
Energy Savings ◽  
Vortex Generator ◽  
Wake Flow ◽  
Container Ship ◽  
Trapezoidal Shape ◽  
Before And After

This research paper describes the CFD work carried out by the authors to investigate the potential energy savings achieved by attaching a Vortex Generator to the hull of a container ship. This is done by computing the flow pattern at the propeller plane before and after the addition of a Vortex Generator, to determine if the addition of the mentioned device presents the propeller with a more favourable inflow. The Vortex Generator is a trapezoidal shape fin attached to the hull which works by inducing vorticity and deflecting streamlines within the boundary layer, thus diverting and equalizing wake flow into the propeller.

scholarly journals Demand Control Strategies of a PCM Enhanced Ventilation System for Residential Buildings

2020 ◽  
Vol 10 (12) ◽  
pp. 4336
Author(s):  
Yue Hu ◽  
Per Kvols Heiselberg ◽  
Tine Steen Larsen
Keyword(s):  
New York ◽  
Energy Storage ◽  
Energy Saving ◽  
Energy Savings ◽  
Control Strategies ◽  
Residential Buildings ◽  
Ventilation System ◽  
Airflow Rate ◽  
Energy Saving Potential ◽  
Demand Control

A ventilated window system enhanced by phase change material (PCM) has been developed, and its energy-saving potential examined in previous works. In this paper, the ventilation control strategies are further developed, to improve the energy-saving potential of the PCM energy storage. The influence of ventilation airflow rate on the energy-saving potential of the PCM storage is firstly studied based on an EnergyPlus model of a sustainable low energy house located in New York. It shows that in summer, the optimized ventilation airflow rate is 300 m3/h. The energy-saving of utilizing a ventilated window with PCM energy storage is 10.1% compared to using a stand-alone ventilated window, and 12.0% compared to using a standard window. In winter, the optimized ventilation airflow rate is 102 m3/h. The energy-saving of utilizing a ventilated window with PCM energy storage is 26.6% compared to using a stand-alone ventilated window, and 32.8% compared to using a standard window. Based on the optimized ventilation airflow rate, a demand control ventilation strategy, which personalizes the air supply and heat pump setting based on the demand of each room, is proposed and its energy-saving potential examined. The results show that the energy savings of using demand control compared to a constant ventilation airflow rate in the house is 14.7% in summer and 30.4% in winter.

scholarly journals Assessment of Energy Saving Potential by Replacing Conventional Materials by Cross Laminated Timber (CLT)—A Case Study of Office Buildings in China

2019 ◽  
Vol 9 (5) ◽  
pp. 858 ◽  
Author(s):  
Yu Dong ◽  
Xue Cui ◽  
Xunzhi Yin ◽  
Yang Chen ◽  
Haibo Guo
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Southern China ◽  
Computational Simulation ◽  
Northern China ◽  
Office Buildings ◽  
Reference Structure ◽  
Cross Laminated Timber ◽  
Climatic Regions ◽  
Heating And Cooling

This research evaluates the operational heating and cooling energy consumption of cross-laminated timber (CLT) office buildings in China. The evaluations involve a comparison of the energy consumption of a reference RC structure and CLT system office buildings. Computational simulation results are based on IES-VE 2019 and show that the estimated heating energy saving ratio of CLT buildings in Harbin, Beijing, Shanghai, and Kunming to the reference structure are 11.97%, 22.11%, 30.94%, and 23.30% respectively. However, the CLT buildings consume more energy for cooling in the summer. The results of the research show significantly higher heating energy reductions for CLT buildings in the Cold Region and Severe Cold Regions of China. Thus, the application of the CLT system is better suited to northern China than southern China. The results of the research can be used in further assessment of the use of CLT systems in different climatic regions in China.

Influence of Volumetric Capacity on Energy Consumption in Oil-Lubricated Compressed Air Systems

2016 ◽  
Vol 8 (4) ◽  
Author(s):  
Pawel Olszewski ◽  
Claus Borgnakke
Keyword(s):  
Mathematical Model ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Potential Energy ◽  
Uncertainty Analysis ◽  
Control Strategy ◽  
Energy Savings ◽  
Compressed Air ◽  
Numerical Code ◽  
Volumetric Capacity

The aim of this research is to estimate the influence of compressed air volumetric capacity on the energy consumption in systems equipped with oil-lubricated screw compressors. A mathematical model of oil-lubricated screw compressors has been proposed. The model is verified by comparing with real measurements, and overall uncertainty analysis is estimated. An in-house developed numerical code (c++) is used to calculate the energy consumption in 252,000 combinations. The final result can be used to estimate the energy efficiency of existing air systems and to assess potential energy savings due to changes in the operation of the system and its control strategy.

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.

Analysis for Energy Savings Potential and Economics of Combined Air-Conditioning System with Temperature and Humidity Decoupled Treatment

2011 ◽  
Vol 280 ◽  
pp. 71-75
Author(s):  
Zhong Chao Zhao ◽  
Dong Hui Zhang ◽  
Yu Ping Chen
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Air Conditioning ◽  
Energy Savings ◽  
Operating Cost ◽  
Air Conditioning System ◽  
Operation Mechanism ◽  
Energy Saving Potential ◽  
Temperature And Humidity

In this paper, the operation mechanism of combined air-conditioning system with temperature and humidity decoupled treatment (CACSTHDT) was presented, and the energy saving potential and economics of CACSTHDT were primarily analyzed through compared with a traditional air-conditioning system. The results indicated that CACSTHDT could save up to 28.64% energy consumption in comparison with a traditional air-conditioning system. The operating cost in one summer only was 71.36% of that cost of traditional air-conditioning system.

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