5 research outputs found
Survey on opportunities and barriers in lighting controls
This report summarizes a survey performed in eight countries on the status quo of daylight and electric lighting control systems. Feedback from more than 100 international experts (building / facility managers and planers) was evaluated. The aim of the survey was to identify the perception of the different possibilities of the current lighting control solutions and the expectations about the control systems. The survey aims to provide a mapping of the current lighting control systems available at the market and an overview of which functions are perceived as most important and which areas are found to be improved. Participants of the survey had to rank each question in relation to the perceived importance and the need for improvement. The survey enclosed five general topics; energy, operational aspects, occupant control, occupant comfort and control functionality.The findings from the summary suggest, that the two main reasons for the implementation of lighting control systems are:1. The possibility to reduce the electric lighting consumptions and2. The opportunity to increase the user’s well-being and thereby reduce complaints from the users.From a user perspective, this means that the lighting system must ensure visual acuity and comfort by providing a sufficient level of illuminance and the ability to regulate the light level. Always in relation to the task and the ambient light in the space, and thereby creating a pleasant and comfortable light environment. Research suggests, when giving the users some manual control possibilities, the satisfaction with the lighting conditions in general increases The users should be able to both increase and dim the light levels or completely turn it off. Thissuggests, if the lighting control system is designed to regulate the illuminance automatically, it should be provided some kind of manual override. This is supported by the findings in the surveys, where all countries in one way oranother find it important to provide the users with some possibility of user control. This as well applies to the control of the shading system in relation to avoid glare from high daylight intensities and undesired solar radiationcoming into the space. This increases the risk of overheating, resulting in an increased ventilation and/or cooling need leading to a higher energy use. However, in the two Scandinavian countries, it is found less important withthe possibility to control the shadings in order to reduce glare from daylight and undesired heat transmission in the space. This may be due to the higher latitude and thereby a lower intensity of the daylight.In relation to the importance of user control, the findings additionally suggest, that the occupant control must be simple to operate. A control system which is easy for the users to understand intuitive, will most likely increase the chances of an ‘optimal’ interaction with the system. If the system does not meet the users need or is too complex to use, the possibility that the users will try to override the control systems increases, and this will most likely result in increased energy consumption
Licht in scholen - Van beginner tot expert
Uit studies is gebleken dat het visueel comfort in klaslokalen een impact heeft op het leerproces (op de concentratie en vitaliteit van de leerlingen), maar ook op de algemene gezondheid en het welzijn van de leerlingen en leerkrachten. Bij het uitwerken van een lichtconcept voor een gebouw is een combinatie van daglicht en kunstlicht nodig. Door de (r)evolutie in ledverlichting zijn zeer energie-efficiënte oplossingen beschikbaar, die we bovendien naar wensen en behoeften kunnen sturen via lichtregelsystemen.
De onderzoeksgroepen Laboratorium voor Lichttechnologie en Duurzaam Bouwen van KU Leuven Technologiecampus Gent hebben samen met Pixii vzw (nieuwe naam van Passiefhuis-platform) en het Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf een jaar lang 10 klaslokalen gemonitord en de mogelijkheden van verschillende types daglichtregelsystemen bestudeerd in het kader van het TETRA-project “Impact van daglichtregelsystemen op ontwerp en renovatie van schoolgebouwen”. De publicatie ‘Licht in scholen: van beginner tot expert’ bundelt de bevindingen van dit project. De publicatie biedt scholen, gebouwbeheerders, architecten en ontwerpers een leidraad aan bij het maken, beoordelen en verbeteren van het lichtontwerp van de klaslokalen.Uitvoerders:
1) KU Leuven Technologiecampus Gent: Laboratorium voor Lichttechnologie en Onderzoeksgroep Duurzaam Bouwen
2) Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf (WTCB): Labo Licht
3) Pixii vzw
Ontwerp en vormgeving: Pixxii vzw in samenerking met sorryklaas
Verantwoordelijke uitgever: Wouter Ryckaert, KU Leuven Technologiecampus Gentnrpages: 144status: publishe
Analysis of energy savings of three daylight control systems in a school building by means of monitoring
Daylight control systems, which automatically adjust the artificial light levels depending on the daylight penetration, can result in substantial energy savings. However, their energy saving potential cannot be estimated accurately because it depends on several building and system parameters, climate conditions, occupant behaviour and type and commissioning of the daylight control system. The objective of this paper is to compare the energy saving potential and operation of different daylight control systems in school buildings. One year monitoring has been carried out simultaneously in 3 neighbouring classrooms, equipped with a different type of control system. The active power and the electric energy consumption of the artificial lighting were measured continuously on a minute-by-minute basis, as well as the occupancy of the classrooms and the global irradiance outside the building under an unobstructed horizon. Momentary visual comfort assessments were carried out in the classrooms.
Although all classrooms have comparable occupancy and identical building characteristics, differences between the annual energy savings of the different daylight control systems are found to be significant: the total annual energy savings varied from 18% to 46%. Under the given conditions, the open loop system with the outward facing daylight sensor was noticed to yield the largest while the closed loop system with centrally positioned sensor produced the smallest savings. However, it has to be made sure that the energy savings are not at the expense of the visual comfort. The performance of the systems regarding both energy savings and visual comfort is related to the operation and the initial commissioning. An in-depth analysis of the monitoring campaign is discussed to explain the differences in energy savings and visual comfort. The energy savings due to the implementation of a daylight control system are divided into on the one hand dimming due to daylight penetration and on the other hand initial dimming to compensate for the over dimensioning of the lighting system and to take into account constant illuminance control.publisher: Elsevier
articletitle: Analysis of energy savings of three daylight control systems in a school building by means of monitoring
journaltitle: Energy and Buildings
articlelink: http://dx.doi.org/10.1016/j.enbuild.2016.06.033
content_type: article
copyright: © 2016 Elsevier B.V. All rights reserved.status: publishe
Survey on opportunities and barriers in lighting controls
This report summarizes a survey performed in eight countries on the status quo of daylight and electric lighting control systems. Feedback from more than 100 international experts (building / facility managers and planers) was evaluated. The aim of the survey was to identify the perception of the different possibilities of the current lighting control solutions and the expectations about the control systems. The survey aims to provide a mapping of the current lighting control systems available at the market and an overview of which functions are perceived as most important and which areas are found to be improved. Participants of the survey had to rank each question in relation to the perceived importance and the need for improvement. The survey enclosed five general topics; energy, operational aspects, occupant control, occupant comfort and control functionality. The findings from the summary suggest, that the two main reasons for the implementation of lighting control systems are:
1. The possibility to reduce the electric lighting consumptions and
2. The opportunity to increase the user’s well-being and thereby reduce complaints from the users.
From a user perspective, this means that the lighting system must ensure visual acuity and comfort by providing a sufficient level of illuminance and the ability to regulate the light level. Always in relation to the task and the ambient light in the space, and thereby creating a pleasant and comfortable light environment. Research suggests, when giving the users some manual control possibilities, the satisfaction with the lighting conditions in general increases The users should be able to both increase and dim the light levels or completely turn it off. This suggests, if the lighting control system is designed to regulate the illuminance automatically, it should be provided some kind of manual override. This is supported by the findings in the surveys, where all countries in one way or another find it important to provide the users with some possibility of user control. This as well applies to the control of the shading system in relation to avoid glare from high daylight intensities and undesired solar radiation coming into the space. This increases the risk of overheating, resulting in an increased ventilation and/or cooling need leading to a higher energy use. However, in the two Scandinavian countries, it is found less important with the possibility to control the shadings in order to reduce glare from daylight and undesired heat transmission in the space. This may be due to the higher latitude and thereby a lower intensity of the daylight.
In relation to the importance of user control, the findings additionally suggest, that the occupant control must be simple to operate. A control system which is easy for the users to understand intuitive, will most likely increase the chances of an ‘optimal’ interaction with the system. If the system does not meet the users need or is too complex to use, the possibility that the users will try to override the control systems increases, and this will most likely result in increased energy consumption
Evaluating integrated lighting projects - A Procedure to Post-Occupancy Evaluation of Daylight and Electrical Lighting Integrated Projects
This report presents tools for post-occupancy evaluation (POE) to evaluate indoor lighting of commissioned projects (‘case studies’) under a common framework. In this report, POE includes technical environmental assessment (TEA) and observer-based environmental assessment (OBEA). The framework proposed in this report evaluates four key aspects of the case study:
1. Energy use (electrical lighting systems),
2. Visual effects (Indoor lighting environment /photometry)
3. Non-visual effects (circadian potential), and
4. The user (subjective/surveys and observations)
The report targets industry professionals, building designers, lighting designers, building managers, researchers and/or owners wishing to evaluate projects where lighting is supplied by a combination of electrical lighting, daylighting systems (e.g., fenestrations) and assisted technologies (e.g., smart sensors). The framework in this report makes available methods and procedures related to the evaluation of integrated lighting performance in residential and non-residential buildings and its impact on users, and it summarises and categorize methods and procedures in an accessible and industry-oriented language.
The content of this document is based on methods and procedures used by participating experts in IEA SHC Task 61 for monitoring twenty-five worldwide integrated daylighting and electric lighting case studies. Since integrated lighting projects are different in type and scopes, the methods and procedures included in the framework do not follow a rigid protocol. Practitioners should use the framework to define the scope of POE monitoring in terms of the aims of the project, context, and resources available. The document is thus a toolbox for planning and executing the monitoring of their integrated lighting projects