The LED Paradox: How Light Pollution Challenges Experts to Reconsider Sustainable Lighting

In the 21st century, the notion of “sustainable lighting” is closely associated with LED technology. In the past ten years, municipalities and private light users worldwide have installed light-emitting diodes in urban spaces and public streets to save energy. Yet an increasing body of interdisciplinary research suggests that supposedly sustainable LED installations are in fact unsustainable, because they increase light pollution. Paradoxically, blue-rich cool-white LED lighting, which is the most energy-efficient, also appears to be the most ecologically unfriendly. Biologists, physicians and ecologists warn that blue-rich LED light disturbs the circadian day-and-night rhythm of living organisms, including humans, with potential negative health effects on individual species and whole ecosystems. Can the paradox be solved? This paper explores this question based on our transdisciplinary research project Light Pollution—A Global Discussion. It reveals how light pollution experts and lighting professionals see the challenges and potential of LED lighting from their different viewpoints. This expert feedback shows that “sustainable LED lighting” goes far beyond energy efficiency as it raises complex design issues that imply stakeholder negotiation. It also suggests that the LED paradox may be solved in context, but hardly in principle

LED lighting for greenhouses

Valo on kasvien tärkein energian ja informaation lähde. Kasvihuoneviljelyssä voidaan keinovalaistuksen avulla pidentää kasvukautta sekä tehostaa tuotantoa. Keinovalaistuksen vaatima sähköenergia on merkittävä kuluerä suomalaisessa kasvihuoneviljelyssä. Tässä työssä selvitettiin LED - valaistuksen soveltuvuutta kasvihuoneviljelyyn sekä ledien tuomia etuja nykyisiin järjestelmiin verrattuna. Ledien avulla on mahdollista päästä merkittäviin säästöihin energiankulutuksessa sekä parantaa sadon laatua optimoimalla valaistus viljeltävän kasvin tarpeiden mukaan. Painottamalla spektriä sinisen ja punaisen valon aallonpituuksilla saadaan kasvit hyödyntämään valon energiaa tehokkaammin. Tällä hetkellä markkinoilta ei vielä löydy laajamittaiseen kasvihuoneviljelyyn soveltuvaa lediratkaisua, mutta tutkimus ja tuotekehitys on käynnissä kautta maailman. Lähivuosina onkin odotettavissa merkittäviä muutoksia kasvihuoneiden valaistusjärjestelmiin.Light is the most important source of energy and information for plants. Artificial lighting can be used in greenhouses to enable year-round production and to increase productivity. The electricity needed for the artificial lighting is a major expense in the Finnish greenhouse production. The suitability of LED - lighting for greenhouse production and it's advantages over current lighting solutions were investigated in this work. Major energy savings can be obtained along with increased quality of the plants by using optimised LED - lighting. The light utilisation of plants can be increased by emphasizing the blue and red wavelengths of the light spectrum. Currently no LED - based lighting solutions are available for large-scale greenhouse production but due to the on-going research and development major changes in greenhouse lighting can be expected in the near future

The impact of fluorescent and LED lighting on student attitudes and behavior in the classroom

Abstract Introduction: This study examined empirical research on the effects of high correlated color temperature light-emitting diodes (LED) and fluorescent lighting on students in the classroom. LED is becoming the most recent lighting option for optimal energy efficiency over fluorescent technology. Background: A review of the literature indicates correlated color temperature (CCT) of lighting has nonvisual effects on students, with higher CCT positively impacting attitudes and behavior. The review also revealed current studies regarding dynamic or tunable lighting that adjusts CCT based on desired activity and mood. Data from an original survey analyzed teacher insights and perceptions regarding student attitudes and behaviors associated with existing classroom lighting and the impact of higher color temperature LED. Methods: Participants were pre-K through high school qualified teachers from three schools and/or personal contacts of the principal investigator. Seventy-five teachers responded to the online questionnaire. The survey data suggests teachers perceive higher color temperature lighting positively impacts student alertness, attitude, and energy level; and adjusting light levels throughout a school day positively impacts student engagement. Results and conclusion: Results supported the perception of higher correlated color temperature lighting positively impacting alertness, attitude, and energy level. Findings also supported the ability to change light levels throughout the school day to positively impact student engagement and mood. There were mixed results regarding higher correlated color temperature impacting attention and on-task/off- task behaviors. Results regarding the impact of sound and flickering from fluorescent lights were not significant

MODERNISATION OF POWER PLANT LIGHTING WITH LED LIGHTING

A substantial part of the power consumption of a power plant on stand-by is due to lighting. As the need to cut power plant’s own electrical energy usage grows, the power consumption of lighting becomes a potential area of improvement. The objective of this thesis is to study the possibility of installing light emitting diode (LED) lighting in a Wärtsilä power plant. Additionally, the objective is to list the rel e-vant international lighting standards. The LED lighting technology appears to have desirable properties, which is why LED lamps were chosen to be compared in this study. Real life examples of power plant rooms were chosen as a base for simulations. Original lighting simulatio ns were com-pared against a new set of simulations with LED technology lighting. Quality of light-ing, energy use and costs of installation and maintenance interval were compared. In three different simulations of engine hall, LED lamps did not appear to be the prefer-able choice for lighting. Compared to linear fluorescent lamps, LED lamps either co n-sumed more electrical energy, required more luminaires to be installed or lowered the lighting quality of the engine hall, depending on the chosen LED lamp types. In conclusion, LED lighting was found not being suitable for this application. The lamps based on LED lighting technology seem to be unable to compete against the older lighting technolo gy lamps such as linear fluorescent t ubes and high intensity discharge lamps in aspects of energy consumption and light distribution in an industrial setting. Tested LED lamps did not produce enough lumens per watt and did not distribute the light well enough when compared to the older solutionfi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Visual Comfort with LED Lighting

A widely accepted definition of human comfort does not exist, but several metrics have been developed to quantify how much users appreciate environments, objects or interfaces. For visual comfort one of the most widely accepted approach is “that comfort is not discomfort”, because it is easier to provide quantitative and qualitative evaluation of visual discomfort parameters rather than comfort parameters that we don’t have a definition of. This paper presents the available suggestions and the results of a European research project about the visual comfort with LED lighting

Colour appearance in led lighting

The paper shows a comparative study of colour comparison between white LED lamps and conventional ones (incandescent and compact fluorescent). The LED lamps used were a model designed by the direct replaces of halogen incandescent lamps. The technology used for white light generation was based on short waves emitter chips and secondary emission. As result of the experience, significant object colour coordinates displacements in LEDs lighting were observed. As it was predictable from LEDs spectral distribution, orange – red colours were poorly reproduced. However, the subjective experience did not show a remarkable preference to the conventional light sources. Furthermore, several observers qualified the objects under LEDs light as “more naturals”

Examining the opportunities of importing LED Lighting from China to New Zealand

The aim of my research was to undertake a feasibility study on how to diversify a China LED business in New Zealand. This research focuses on the feasibility study of associating with the LED lighting market. The primary analysis consisted of interviewing the owner of the particular business. Because it was a feasibility study it was not necessary to interview customers; I used a qualitative method to gain information. The overall results outline that the company has a professional team in their group, but they do not have a good foreign platform that can sell their products. The owner has sufficient funding himself to open up a branch in New Zealand., He will use his money to invest in prospective properties with a high return. The discussion was about the artificial lighting bulb which is taking up roughly 20% of the world’s energy consumption. However, more energy efficient LED lights can be an alternative to replace that 70 % of other lights. The conclusion was that most lighting companies have started manufacturing LED lights, and certain Chinese manufacturers are entering the market with cheaper LED products. LED does contain some poisonous substances such as gallium arsenide. The quantity of this substance is very small and thus LED can be considered as a greener alternative to fluorescent lamps. The recommendations could be people should pay more attention to LED bulbs in that they are energy saving and environmentally sound, which it is a good way to protect the environment