Building Lighting Systems Research Articles

IMPACT OF RETROFITTING ENERGY-EFFICIENT DESIGN STRATEGIES ON ENERGY USE OF EXISTING COMMERCIAL BUILDINGS: COMPARATIVE STUDY OF LOW-IMPACT AND DEEP RETROFIT STRATEGIES

This article discusses energy-efficient retrofitting design strategies for commercial office buildings, and examines their effect on energy consumption. The objective of the research was to study how to integrate passive design strategies and energy-efficient building systems to improve building performance, and reduce the energy consumption of existing buildings in three different climate types (cold, mixed and hot climates). First, properties of existing buildings were analyzed based on national CBECS database to determine typical characteristics of office buildings located in Chicago, Baltimore and Phoenix, including size, building envelope treatment and building systems. Then, fourteen different prototypes were developed, varying the building shape and orientation to represent different building stock, and energy modeling was conducted to establish energy usage baseline. Multiple design considerations were investigated based on extensive energy simulations and modeling, where low-impact and deep retrofits were considered. Low-impact strategies included improvements to the building envelope, lighting systems and optimization of HVAC systems operation (without upgrading heating and cooling equipment). Deep energy retrofits also included improvements to building envelope and lighting, and considered changes and improvements to HVAC systems (specifically, integration of radiant systems). Energy modeling was conducted for all prototypes, and results were obtained for the baseline (current energy usage), and energy usage considering low-impact design strategies and deep retrofits. A total of 126 energy models was developed, simulated and analyzed, providing a dataset that captured energy usage for investigated scenarios. The comparative analysis of simulation results was used to determine how specific techniques lead to energy savings in different climate types, as well as for buildings of various shapes and orientations.

Minimizing computational cost and energy demand of building lighting systems: A real time experiment using a modified competition over resources algorithm

Lighting systems in buildings have substantial influence on both the occupants' productivity and energy efficiency. This paper addresses the problem of minimizing the energy necessary to provide predefined scheduled lighting levels upon a set of targets through an optimization technique. An experimental setup has been designed, built and used to gather data regarding the influences of five light sources upon three targets. The optimization problems corresponding to different lighting demands were solved with the recently introduced Competition Over Resources bio-inspired metaheuristic optimization algorithm. Modifications on this algorithm were proposed in order to enhance its performance in terms of convergence speed and computational effort. The modified algorithm was firstly tested with classical benchmark functions, and then with a real time lighting problem. Once algorithm performance improvements were verified, the energy consumption over a scheduled lighting demand was measured under different test conditions as to evaluate potential savings whilst minimizing the computational cost of running the algorithm. Using the proposed modifications, the best parameters for each lighting demand condition in the predefined schedule have been identified. By using these parameters along with a strategy of reusing the best solution while the lighting demand does not change, smaller population sizes in the algorithm could be used. Finally, the minimum algorithm population size at which energetic performance begins to be affected was identified. Promising results in terms of energy efficiency and reduced computational effort were achieved.

Building Energy Management Systems: The Age of Intelligent and Adaptive Buildings

Building automation systems (BAS), or building control systems (BCS), typically consist of building energy management systems (BEMSs), physical security and access control, fire/life safety, and other systems (elevators, public announcements, and closed-circuit television). BEMSs control heating, ventilation, and air conditioning (HVAC) and lighting systems in buildings; more specifically, they control HVAC?s primary components such as air handling units (AHUs), chillers, and heating elements. BEMSs are essential components of modern buildings, tasked with seemingly contradicting requirements?minimizing energy consumption while maintaining occupants? comfort [1]. In the United States, about 40% of total energy consumption and 70% of electricity consumption are spent on buildings every year. These numbers are comparable to global statistics that about 30% of total energy consumption and 60% of electricity consumption are spent on buildings. Buildings are an integral part of global cyberphysical systems (smart cities) and evolve and interact with their surroundings (Figure 1) [2]. As buildings undergo years of exploitation, their thermal characteristics deteriorate, indoor spaces (especially in commercial buildings) get rearranged, and usage patterns change. In time, their inner (and outer) microclimates adjust to changes in surrounding buildings, overshadowing patterns, and city climates, not to mention building retrofitting [3], [4]. Thus, even in cases of ?ideally? designed BEMS/HVAC systems, because of ever-changing and uncertain indoor and outdoor environments, their performance frequently falls short of expectations. Unfortunately, the complexity of BEMSs, large amounts of constantly changing data, and evolving interrelations among sensor feeds make identifying these suboptimal behaviors difficult [1], [5]. Therefore, traditional data-mining algorithms and data-analysis tools are often inadequate.

Artificial Versus Natural Light Source Identification with Light Intensity Sensors for Energy Monitoring

Studies have shown that increasing the granularity of energy consumption information in buildings could facilitate achieving energy saving objectives. Lighting systems in buildings are one of the main consumers of electricity with a share of approximately (direct and indirect) 23 percent of the total electricity in the US. Direct monitoring of lighting systems is not feasible due to challenges for instrumentation. In this study, we are proposing an approach for monitoring of lighting systems energy consumption by using single light intensity sensors. Load monitoring through light sensors is challenging due to the contribution of natural light in variation of the signal magnitude in the captured time series. Accordingly, we have proposed a new feature in frequency domain that helps us identify artificial light (AL) source type and improve AL event detection. Field experimental study showed the effectiveness of the proposed feature by eliminating all false positives in event detection.

High-Performance Renovation of Iranian Historical Buildings to Substitute Active Lighting Systems with Natural Light (Case Study: Shahi Bank, Tehran)

In this research, building lighting systems and façade glazing system and architectural design of ‘Shahi Bank’ have been evaluated and developed on the basis of the analysis on natural light patterns, which have been derived based on the simulation process by ECOTECT software.During the simulation process, both conditions before and after the design, have been examined and compared with each other. The results from simulations show that absence of appropriate light levels in the middle of the main hall can be solved by locating three light tubes, which could provide an adequate natural light level for this space.

Retrofitting Solutions for Energy Saving in a Historical Building Lighting System

The study evaluates the potential energy saving achievable by replacing the existing lighting system in a historical building.The analysis focused on an office in the Abbey of San Lorenzo ad Septimum, that is located in Aversa (southern Italy) and houses the Department of Architecture and Industrial Design of the Second University of Naples.The influence of various actions, such as different types, different arrangement and different mounting height of luminaires and different walls reflectance values were evaluated in terms of Lighting Energy Numeric Indicator LENI and illuminance uniformity. Finally, the influence of three different types of windows were considered.

Energy savings analysis and harmonics reduction for the electronic ballast of T5 fluorescent lamp in a building's lighting system

Lighting is one of the major energy end uses, which accounts for approximately 20–30% of electricity consumption in buildings. In fact, the fluorescent lamp is the most employed lamp in a lighting system for both inside and outside the building. The ballast is one of the major components of fluorescent lamps; it exists commercially as an electromagnetic ballast, a low loss ballast and an electronic ballast. To reduce energy consumption in a lighting system, the electronic ballast has already been introduced for profit in terms of its peak demand reduction and energy conservation in the building. However, when the electronic ballast functions, harmonics will be generated. Hence, this paper investigates energy savings and the generation of harmonics when using a fluorescent T5 lamp with electronic ballast in a building. The efficiency indices in terms of illumination, energy savings, and harmonics are also evaluated and compared with the fluorescent T8 lamp operating with a low watt loss electromagnetic ballast, which is also widely used. The obtained results are useful for the design and decision to install a fluorescent T5 lamp with electronic ballast in building lighting system to conserve energy and/or reduce energy consumption for the future of the country.

Retrofitting the Electric Lighting and Daylighting Systems to Reduce Energy Use in Buildings: A Literature Review

This paper presents a literature review about energy-efficient retrofit of electric lighting and daylighting systems in buildings. The review, which covers around 160 research articles, addresses the following themes: 1) retrofitting electric lighting in buildings, 2) electric lighting energy use and saving potential and 3) lighting retrofit strategies. The retrofit strategies covered in the review are: replacement of lamp, ballast or luminaire; use of task-ambient lighting design; improvement in maintenance; reduction of maintained illuminance levels; improvement in spectral quality of light sources; improvement in occupant behavior; use of control systems; and use of daylighting systems. The review indicates that existing general knowledge about lighting retrofit is currently very limited and that there is a significant lack of information concerning the actual energy performance of lighting systems installed in the existing building stock. The resulting key directions for future research highlights issues for which a better understanding is required for the spread and development of lighting retrofit. (Less)

Efficiency assessment of balancing devices application in the lighting systems of buildings

In the article there are discussed the using of balancing devices in lighting systems of buildings carried out on the basis of lighting devices with LED light sources, in order to increase their efficiency by eliminating the single-ended modes, which arise at random switching on and switching off the power single-phase receivers and lighting loads. It is proposed the possible variants for power supply of lighting devices with LED light sources, including through the balancing thyristor voltage regulator, which is a source of direct current and fully balanced the load. Transition to the DC power supply will help reduce losses, costs of electricity and the higher harmonic components of current and voltage, increase the coefficients of power, reliability and electrical safety of these systems. The technical and economic evaluation of different variants of power supply of LED light sources is done in the article, the variant with the best specifications is proposed. It is proposed in the future to perform the scheme of power supply of buildings in combined variant, which implies the power supply of power electrical receivers from AC 380/220 V, and the lighting power consumers - from the DC network.

User satisfaction adaptive behaviors for assessing energy efficient building indoor cooling and lighting environment

Abstract Many techniques for managing sustainability including sustainable building assessment tools and standards have been developed globally. The sustainable building assessment tools measure the user satisfaction dependent to environmental and economic aspects of energy efficient building practices. However, these tools have not yet measure energy efficiency index by involving user satisfaction from adaptive behaviors dependently, which can determine the actual energy consumption versus the planed energy consumption of the building. Hence, this research aimed at providing a comprehensive list of adaptive behaviors for assessing energy efficient building indoor environment in design phase of building lifecycle. The study focused on identifying and establishing adaptive behaviors that are in response to indoor conditions provided by Cooling and Lighting systems in energy efficient office buildings. This research involves adaptations across Technological and Personal. The research was conducted in two phases. Phase one identified the list of user satisfaction adaptive behaviors through a systematic approach. Next, an expert input study was conducted to validate the findings of the literature review. Expert input data was collected using Delphi structured close group discussion method, and then analyzed through Grounded Group Decision Making (GGDM) method. Eight experts were involved in four sessions of the GGDM application procedure. The research established 18 adaptive behaviors relevant to cooling system in energy efficient indoor environments, and 18 adaptive behaviors relevant to the lighting system. The comprehensive list of user satisfaction adaptive behaviors can be applied in both current and future sustainable building assessment tools׳ energy efficiency indexes. This aids architects, engineers, facility managers, building owners, consultants, authorities, contractors, and academic researchers in accreditation of building users, building design and reduction of building׳s energy consumption.

Research of Communication Method of Intelligent Building Lighting System Based on CAN Bus

This paper proposes an intelligent lighting control system based on CAN. Compared with the traditional lighting control system, it overcomes the effect of relatively scattered control and disadvantages of poor management, poor real-time and low degree of automation. In explaining the overall design of intelligent lighting system framework and communication protocols based on CAN bus communication, it analyzes the real time capability and puts forward the optimization scheme. It also proposes an implementation of SJA1000 CAN communication modules to achieve application to intelligent lighting system.

Acoustics and Lighting Education in Architectural Engineering: Experience of WPI

AbstractThe growing complexity of buildings requires architectural engineering to integrate many different specialized capabilities, among which building physics often plays a primary role. Architectural engineers must understand all building systems and be able to apply physics principles to the building envelope and indoor environment. This paper discusses the content and educational approaches of two new courses, Building and Architectural Acoustics and Building Electrical and Lighting Systems, in the new architectural engineering program at Worcester Polytechnic Institute (WPI). For both courses, teaching through project-oriented education presents unique challenges. The projects the classes focused on included optimizing the lighting design at the Worcester Art Museum and the acoustic design in WPI classrooms. This hands-on approach, focusing on both actual measurements and simulations, encourages students to develop a professional attitude for applying theoretical principles to the solution of engin...

Spatiotemporal lighting load disaggregation using light intensity signal

Lighting systems in commercial buildings are major contributors to the electricity consumption while occupants of these buildings are usually not aware of the effect of their energy-related behavior on the electricity consumption. A non-intrusive load disaggregation approach for lighting systems in office buildings was proposed and evaluated to provide high granularity spatiotemporal load monitoring. In our approach, we proposed a process for artificial light event detection and power consumption estimation using light intensity signals and rooms’ contextual information (i.e. room area and number of possible states for lighting fixtures). Three event detection algorithms: generalized likelihood ratio test, signal-shape driven event detection, and enhanced naïve event detection were proposed and evaluated. The signal-shape driven event detection algorithm outperformed on data collected in rooms where the natural light was used in conjunction with artificial light source. The correlation between the illuminance in a room and power consumption associated with that level of illuminance was used for power consumption estimation. The evaluations in rooms (with and without natural light) showed the feasibility of accurate power estimation when the sensor is installed closer to the floor and the estimation is informed by the possible operating states of lighting fixtures.

Design of Intelligent Building Lighting System Based on CAN Bus

The traditional lighting control system has the problem that short communication distance, slow transmission speed and high error rat. This paper presents and designs an intelligent lighting control system based on CAN bus. Describing the design framework of intelligent lighting system, it focuses on the realization of CAN communication module of SJA1000. The intelligent lighting control system based on CAN bus is a distributed intelligent control system. Compared with the traditional lighting control system, it overcomes the effect of relatively scattered control and disadvantages of poor management, poor real-time and low degree of automation.

Lighting control strategy for energy efficient office lighting system design

Lighting is the highest consumer of electrical energy in office buildings and it is one of the areas that offer many opportunities for improving the energy efficiency thereby reducing the energy consumption. This paper presents control strategy for energy efficient office lighting system design. The energy efficiency of a typical office building lighting system in Dubai is examined in this paper. The impact of use of natural lighting and artificial lighting on the HVAC system is assessed and highlighted. Lighting control algorithm is developed with the ultimate goal of achieving energy efficiency and health aspects of occupants into consideration. It is simulated using control systems simulation software functional explorer (FX) tools and recommendations are forwarded. The proposed control algorithm can be used as a reference to other new buildings to be built in Dubai or Middle East in general.

설비공학 분야의 최근 연구 동향 : 2012년 학회지 논문에 대한 종합적 고찰

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2012. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. The conclusions are as follows : (1) The research works on thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and valves, fuel cells and power plants, ground-coupled heat pumps, and general heat and mass transfer systems. Research issues are mainly focused on new and renewable energy systems, such as fuel cells, ocean thermal energy conversion power plants, and ground-coupled heat pump systems. (2) Research works on the heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, and industrial heat exchangers. Researches on heat transfer characteristics included the results for natural convection in a square enclosure with two hot circular cylinders, non-uniform grooved tube considering tube expansion, single-tube annular baffle system, broadcasting LED light with ion wind generator, mechanical property and microstructure of SA213 P92 boiler pipe steel, and flat plate using multiple tripping wires. In the area of pool boiling and condensing heat transfer, researches on the design of a micro-channel heat exchanger for a heat pump, numerical simulation of a heat pump evaporator considering the pressure drop in the distributor and capillary tubes, critical heat flux on a thermoexcel-E enhanced surface, and the performance of a fin-and-tube condenser with non-uniform air distribution and different tube types were actively carried out. In the area of industrial heat exchangers, researches on a plate heat exchanger type dehumidifier, fin-tube heat exchanger, an electric circuit transient analogy model in a vertical closed loop ground heat exchanger, heat transfer characteristics of a double skin window for plant factory, a regenerative heat exchanger depending on its porous structure, and various types of plate heat exchangers were performed. (3) In the field of refrigeration, various studies were executed to improve refrigeration system performance, and to evaluate the applicability of alternative refrigerants and new components. Various topics were presented in the area of refrigeration cycle. Research issues mainly focused on the enhancement of the system performance. In the alternative refrigerant area, studies on CO2, R32/R152a mixture, and R1234yf were performed. Studies on the design and performance analysis of various compressors and evaporator were executed. (4) In building mechanical system research fields, twenty-nine studies were conducted to achieve effective design of mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, renewable energy systems, and lighting systems in buildings. New designs and performance tests using numerical methods and experiments provide useful information and key data, which can improve the energy efficiency of buildings. (5) In the fields of the architectural environment, studies for various purposes, such as indoor environment, building energy, and renewable energy were performed. In particular, building energy-related researches and renewable energy systems have been mainly studied, reflecting interests in global climate change, and efforts to reduce building energy consumption by government and architectural specialists. In addition, many researches have been conducted regarding indoor environments.

Light Extraction Improvement for LED COB Devices by Introducing a Patterned Leadframe Substrate Configuration

We propose a patterned leadframe substrate (PLS) configuration for light-emitting diode chip-on-board devices (LED COBs) with regular triangular structures on it. The mechanism of this method is analyzed through ray dynamics, which indicate that the light-propagating regimes are considerably different as the structure inclination angle α changes. For typical encapsulant materials (refractive index=1.41), the optimal α is 22.5°~45°. Then the performance of LED COB devices with PLS configurations are verified through 3-D Monte Carlo ray-tracing simulations as well as experimental measurements. Results show that the light-extraction efficiency is significantly improved. A simulated enhancement of 42% and a measured enhancement of 41.07% are observed. These results are in good consistency with the ray dynamic analysis, confirming our predictions about PLS methods. Furthermore, we find that such an LED COB configuration also provides a way to change the angular distribution of intensity from half-peak side angle 101.84° to 141.80°. The findings of our work represent a new concept for LED COB packaging design of great practicality in building lighting systems.

Research on Energy Saving Directing at Building Lighting System

The thesis states the building lighting regulated system composition, basic functions and work processes. Based on the compensation principle, making use of transformer controlled voltage source and the controlled current source model, the thesis analyzes the principle of the system voltage. According to the illumination and life span character of the lighting lamps and lanterns in different voltage, the thesis gets the optimal power supply of building lighting system electric lamps and lanterns. Finally, the building indoor lighting using optimal power supply voltage lighting and energy saving rate of building exterior wall using time-varying stabilized voltage control scheme are analyzed and calculated.

Simple Tool for Energy Analysis of Day Lighting and Artificial Lighting for a Typical Office Building Lighting System Design

Today, energy shortage and carbon emission are the major challenges faced by all countries. There are many ways to tackle this issue by saving energy in many sectors. Lighting is used in many applications and it is one of the areas to be addressed for improving the energy efficiency thereby reducing the energy consumption. In this paper, a typical office building in Dubai is considered for analysis. The first section of the paper reports an efficient use of natural lighting into an office building to improve the energy efficiency. This study is carried out using Simulation software VELUX Daylight Visualizer 2 and simulation results are discussed in detail. The study showed that an ideal office space in Dubai has ample potential to harvest natural light to reduce the need for artificial lighting. In the second section, artificial lighting is used to complement natural lighting to meet the required illumination criteria. DIALux 4.1 Lighting Wizard software is used to design and evaluate artificial lighting scheme with similar illumination abilities for the same office space through the use of different types of lamps and the simulation results are highlighted. Its cost effectiveness is also studied. The impact of use of natural lighting and artificial lighting on HVAC system is examined and highlighted.

Assessment of potential energy saving using cluster analysis: A case study of lighting systems in buildings

The promulgation of a building energy code needs an accurate estimation of potential energy savings to ensure that its implementation can achieve the goal set. Generally, the estimation is carried out using the mean value averaged from sample buildings as a representative for the whole sector. However, the actual data of building energy performance may not be described by a single normal distribution. In this study, cluster analysis is thus introduced to estimate potential energy savings in lighting systems in buildings, in comparison with the general averaging approach. The study covers analyses of both simulated and actual data. The simulated data of lighting power density (LPD) is generated from Gaussian distributions for 36 cases with different means, variances, and mixing proportions for the investigation. For actual data analysis, LPD values of commercial buildings are extracted from an energy audit database. It is found that the clustering technique yields more accurate energy saving estimation of the actual values (0–11% error) than that computed by the general approach (1–100% error). The proposed clustering method can therefore be used to estimate the potential energy savings for lighting systems in buildings with high accuracy.