Energy efficient solid state lighting

Energy Technology Data Exchange (ETDEWEB)

Dam-Hansen, C.; Petersen, Poul Michael

2012-11-15

Even though vast improvements have been made on efficiency and light quality, SSL is still in its infancy. One of the barriers for a market introduction is the price, which still is around 5 times higher than traditional lighting technologies. In order to fulfil the potential of SSL, further research and development needs to increase the light extraction from semiconductor materials, provide better and cheaper production and packaging, and advanced optical systems for optimized light distribution and new thermal solutions for SSL lamps and luminaires. Nanotechnology and applied research at DTU Fotonik in close collaboration with industry are essential parts in the development of new enhanced LED optical systems and LEDs with higher light extraction efficiency. Photonic crystals can help to efficiently extract light from LEDs and to form a desired emission profile. Future directions are devoted to the next generation of LEDs, in which the spontaneous emission is photon enhanced. One realization of this idea is using LEDs with a layer of nanocrystals, which are coupled to the quantum well of the LED. Such R and D work is ongoing all over the world and DOE roadmaps foresee luminous efficiencies by 2020 that are close to 250 lm/W for both cold and warm white light from LEDs, and prices in the order of one dollar per kilolumen. Such figures will drastically reduce the energy consumption worldwide for lighting, and hence a marked reduction in carbon emissions. (Author)

Development of combined brake system on front and rear brakes for scooter; Scooter yo zenkorin rendo brake system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Okazaki, Y; Itabashi, T; Shinohara, S; Honda, Y [Honda R and D Co. Ltd., Tokyo (Japan)

1997-10-01

Scooters need appropriate front and rear wheel braking power distribution and each of front and rear brakes have been operated using right and left levers. This time, a low cost brakes with cable type combined brake system for small size scooter and a brakes with hydraulic type combined brake system for middle size scooter have been developed to obtain appropriate front and rear wheel braking power distribution. Both systems use convenient left lever to operate. 3 refs., 9 figs., 1 tab.

Enabling Autonomous Navigation for Affordable Scooters.

Science.gov (United States)

Liu, Kaikai; Mulky, Rajathswaroop

2018-06-05

Despite the technical success of existing assistive technologies, for example, electric wheelchairs and scooters, they are still far from effective enough in helping those in need navigate to their destinations in a hassle-free manner. In this paper, we propose to improve the safety and autonomy of navigation by designing a cutting-edge autonomous scooter, thus allowing people with mobility challenges to ambulate independently and safely in possibly unfamiliar surroundings. We focus on indoor navigation scenarios for the autonomous scooter where the current location, maps, and nearby obstacles are unknown. To achieve semi-LiDAR functionality, we leverage the gyros-based pose data to compensate the laser motion in real time and create synthetic mapping of simple environments with regular shapes and deep hallways. Laser range finders are suitable for long ranges with limited resolution. Stereo vision, on the other hand, provides 3D structural data of nearby complex objects. To achieve simultaneous fine-grained resolution and long range coverage in the mapping of cluttered and complex environments, we dynamically fuse the measurements from the stereo vision camera system, the synthetic laser scanner, and the LiDAR. We propose solutions to self-correct errors in data fusion and create a hybrid map to assist the scooter in achieving collision-free navigation in an indoor environment.

Enabling Autonomous Navigation for Affordable Scooters

Directory of Open Access Journals (Sweden)

Kaikai Liu

2018-06-01

Full Text Available Despite the technical success of existing assistive technologies, for example, electric wheelchairs and scooters, they are still far from effective enough in helping those in need navigate to their destinations in a hassle-free manner. In this paper, we propose to improve the safety and autonomy of navigation by designing a cutting-edge autonomous scooter, thus allowing people with mobility challenges to ambulate independently and safely in possibly unfamiliar surroundings. We focus on indoor navigation scenarios for the autonomous scooter where the current location, maps, and nearby obstacles are unknown. To achieve semi-LiDAR functionality, we leverage the gyros-based pose data to compensate the laser motion in real time and create synthetic mapping of simple environments with regular shapes and deep hallways. Laser range finders are suitable for long ranges with limited resolution. Stereo vision, on the other hand, provides 3D structural data of nearby complex objects. To achieve simultaneous fine-grained resolution and long range coverage in the mapping of cluttered and complex environments, we dynamically fuse the measurements from the stereo vision camera system, the synthetic laser scanner, and the LiDAR. We propose solutions to self-correct errors in data fusion and create a hybrid map to assist the scooter in achieving collision-free navigation in an indoor environment.

Casino Rama hits the jackpot with energy-efficient lighting

Energy Technology Data Exchange (ETDEWEB)

Anon.

2007-10-15

A lighting retrofit program was conducted by Casino Rama in an effort to improve quality while reducing costs and environmental impacts. Casino Rama, Ontario's only commercial First Nation's casino, was opened in July 1996. With over 25,000 bulbs in use, the facility had a lot to gain by reducing energy costs. Toronto Hydro (TH) Energy Services evaluated the facility's current usage level and recommended ways to increase energy efficiency. The casino used mostly incandescent and fluorescent lights which provided adequate light, but which required a great deal of upkeep. The operators wanted to relamp the lighting package that consumed the most electricity with high-efficiency lighting systems that would maintain a consistent look with that of the warm-glow provided by incandescent light bulbs. In order to benefit from energy savings, an efficient, non-invasive system was needed with minimal construction costs to retrofit the lighting system. TH Energy concluded that high-quality, longer-lasting lamps were required. TCP Inc. provided energy-efficient compact fluorescent lamps (CFLs) that have an average life of 10,000 hours and use a quarter of the energy of standard incandescent bulbs, resulting in increased energy savings, lower utility costs and greenhouse gas reduction. The retrofit involved the replacement of more than 5,000 bulbs with over 4,000 CFLs being installed on the 3 massive canopies over the casino entrance. Long-life LED products lasting up to 50,000 hours were also used for the glass elevator shaft, which minimized maintenance costs. Cold-cathode lamps that last an average 25,000 hours were recommended for rapid cycle applications such as signage. The relamping process was completed in 7 working days with minimal disruption to business activity. The casino has saved $200,000 from its annual hydro bill and has freed up valuable manpower for other maintenance-related tasks. The relamping is reducing greenhouse gas emissions by 7 to 8

Casino Rama hits the jackpot with energy-efficient lighting

Energy Technology Data Exchange (ETDEWEB)

Anon,

2007-10-15

A lighting retrofit program was conducted by Casino Rama in an effort to improve quality while reducing costs and environmental impacts. Casino Rama, Ontario's only commercial First Nation's casino, was opened in July 1996. With over 25,000 bulbs in use, the facility had a lot to gain by reducing energy costs. Toronto Hydro (TH) Energy Services evaluated the facility's current usage level and recommended ways to increase energy efficiency. The casino used mostly incandescent and fluorescent lights which provided adequate light, but which required a great deal of upkeep. The operators wanted to relamp the lighting package that consumed the most electricity with high-efficiency lighting systems that would maintain a consistent look with that of the warm-glow provided by incandescent light bulbs. In order to benefit from energy savings, an efficient, non-invasive system was needed with minimal construction costs to retrofit the lighting system. TH Energy concluded that high-quality, longer-lasting lamps were required. TCP Inc. provided energy-efficient compact fluorescent lamps (CFLs) that have an average life of 10,000 hours and use a quarter of the energy of standard incandescent bulbs, resulting in increased energy savings, lower utility costs and greenhouse gas reduction. The retrofit involved the replacement of more than 5,000 bulbs with over 4,000 CFLs being installed on the 3 massive canopies over the casino entrance. Long-life LED products lasting up to 50,000 hours were also used for the glass elevator shaft, which minimized maintenance costs. Cold-cathode lamps that last an average 25,000 hours were recommended for rapid cycle applications such as signage. The relamping process was completed in 7 working days with minimal disruption to business activity. The casino has saved $200,000 from its annual hydro bill and has freed up valuable manpower for other maintenance-related tasks. The relamping is reducing greenhouse gas emissions by 7 to 8 per cent, based

Comparison of moped, scooter and motorcycle crash risk and crash severity.

Science.gov (United States)

Blackman, Ross A; Haworth, Narelle L

2013-08-01

The increased popularity of mopeds and motor scooters in Australia and elsewhere in the last decade has contributed substantially to the greater use of powered two-wheelers (PTWs) as a whole. As the exposure of mopeds and scooters has increased, so too has the number of reported crashes involving those PTW types, but there is currently little research comparing the safety of mopeds and, particularly, larger scooters with motorcycles. This study compared the crash risk and crash severity of motorcycles, mopeds and larger scooters in Queensland, Australia. Comprehensive data cleansing was undertaken to separate motorcycles, mopeds and larger scooters in police-reported crash data covering the five years to 30 June 2008. The crash rates of motorcycles (including larger scooters) and mopeds in terms of registered vehicles were similar over this period, although the moped crash rate showed a stronger downward trend. However, the crash rates in terms of distance travelled were nearly four times higher for mopeds than for motorcycles (including larger scooters). More comprehensive distance travelled data is needed to confirm these findings. The overall severity of moped and scooter crashes was significantly lower than motorcycle crashes but an ordered probit regression model showed that crash severity outcomes related to differences in crash characteristics and circumstances, rather than differences between PTW types per se. Greater motorcycle crash severity was associated with higher (>80km/h) speed zones, horizontal curves, weekend, single vehicle and nighttime crashes. Moped crashes were more severe at night and in speed zones of 90km/h or more. Larger scooter crashes were more severe in 70km/h zones (than 60km/h zones) but not in higher speed zones, and less severe on weekends than on weekdays. The findings can be used to inform potential crash and injury countermeasures tailored to users of different PTW types. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of photobiological safety of energy-efficiency urban lighting

Directory of Open Access Journals (Sweden)

Łukasz Stanisław Pierzchała

2018-02-01

Full Text Available Exceeding the safe threshold for exposure on high energy radiation (UV and blue light could cause the emergence of a number of diseases. Eyesight is particularly sensitive to excessive lighting. This paper presents the laboratory research on the assessment of the photobiological risk generated by the energy-efficiency urban lighting. The results show that LED lighting systems can be a source of radiation that significantly negatively affects the eyesight and could contribute to circadian rhythm disorders.

Light's labour's lost - policies for energy-efficient lighting

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-06-29

When William Shakepeare wrote Love's Labour's Lost he would have used light from tallow candles at a cost (today) of 12,000 British pounds per million-lumen hours. The same amount of light from electric lamps now costs only 2 pounds! But today's low-cost illumination still has a dark side. Globally, lighting consumes more electricity than is produced by either hydro or nuclear power and results in CO2 emissions equivalent to two thirds of the world's cars. A standard incandescent lamp may be much more efficient than a tallow candle, but it is far less efficient than a high-pressure sodium lamp. Were inefficient light sources to be replaced by the equivalent efficient ones, global lighting energy demand would be up to 40% less at a lower overall cost. Larger savings still could be realised through the intelligent use of controls, lighting levels and daylight. But achieving efficient lighting is not just a question of technology; it requires policies to transform current practice. This book documents the broad range of policy measures to stimulate efficient lighting that have already been implemented around the world and suggests new ways these could be strengthened to prevent light's labour's from being lost.

Pediatric fractures during skateboarding, roller skating, and scooter riding.

Science.gov (United States)

Zalavras, Charalampos; Nikolopoulou, Georgia; Essin, Daniel; Manjra, Nahid; Zionts, Lewis E

2005-04-01

Skateboarding, roller skating, and scooter riding are popular recreational and sporting activities for children and adolescents but can be associated with skeletal injury. The purpose of this study is to describe the frequency and characteristics of fractures resulting from these activities. Fractures from skateboarding, roller skating, and scooter riding compose a considerable proportion of pediatric musculoskeletal injuries. Case series; Level of evidence, 4. Demographic data and injury characteristics were analyzed for all patients who presented to the pediatric fracture clinic of the level I trauma center from January 2001 to May 2002 after sustaining fractures due to skateboarding, roller skating, and scooter riding. Among a total of 2371 fractures, the authors identified 325 fractures (13.7%) that occurred during one of these activities. There were 187 patients (mean age, 13 years; 95% male) who sustained 191 skateboard-related fractures, 64 patients (mean age, 10.8 years; 54% male) who sustained 65 fractures while roller skating, and 66 patients (mean age, 9.7 years; 64% male) who sustained 69 fractures while riding a scooter. The forearm was fractured most often, composing 48.2% of skate-boarding fractures, 63.1% of roller-skating fractures, and 50.7% of fractures due to scooter riding. Of the forearm fractures, 94% were located in the distal third. In the skateboarding group, 10 of 191 (5.2%) fractures were open injuries of the forearm, compared to 6 of 2046 (0.3%) fractures caused by other mechanisms of injury (significant odds ratio, 18.8). Skateboarding, roller-skating, and scooter-riding accidents result in a large proportion of pediatric fractures. An open fracture, especially of the forearm, was more likely to be caused by skateboarding than by other mechanisms of injury. Use of wrist and forearm protective equipment should be considered in all children who ride a skateboard.

Energy efficiency public lighting management in the cities

International Nuclear Information System (INIS)

Radulovic, Dusko; Skok, Srdjan; Kirincic, Vedran

2011-01-01

Cities all around the world are faced with a rapid increase of urban population, and their crucial sustainable development issue becomes energy management. Moreover, the national energy management sector is slowly passing from government surveillance to the responsibility of local municipalities. The energy efficiency management in cities helps local governments to focus on important energy projects that have strong environmental aspects and financial feasibility. This paper analyzes the public lighting energy management in the Croatian city of Rijeka in order to determine the connection of the energy market liberalization and sustainable development in urban areas. Research results indicate a significant connection between investments in energy management of public lighting and its influence on lower emissions of carbon dioxide (CO 2 ).

Green Lighting. Energy-efficient integrated lighting systems - Final report

Energy Technology Data Exchange (ETDEWEB)

Linhart, F.; Scartezzini, J.-L.

2009-10-15

The objective of the Green Lighting project was to develop a High Performance Integrated Lighting System, based on advanced technologies for day- and electric lighting, achieving a Lighting Power Density (LPD) that does not exceed 3 W/m{sup 2}. The project has revealed that Anidolic Daylighting Systems (ADS) are an ideal basis for High Performance Integrated Lighting Systems. Not only are they able to provide adequate illumination (i.e. sufficiently high illuminance) in office rooms during large fractions of normal office hours, under various sky conditions and over the entire year, but they are also highly appreciated by office occupants at the condition that glare control mechanisms are available. Complementary electric lighting is, however, still necessary to back up the ADS at times when there is insufficient daylight flux available. It was shown during this project, that the most interesting trade-offs between energy-efficiency and visual comfort are obtained by using a combination of ceiling-mounted directly emitting luminaires with very high optical efficiencies for ambient lighting and portable desk lamps for temporary task lighting. The most appropriate lamps for the ceiling-mounted luminaires are currently highly efficient fluorescent tubes, but white LED tubes can be considered a realistic option for the future. The most suitable light sources for desk lamps for temporary task lighting are Compact Fluorescent Lamps (CFLs) and white LED light bulbs. Based on the above-mentioned technologies, a High Performance Integrated Lighting System with a very low LPD has been developed over the last three years. The system has been set up in an office room of the LESO solar experimental building located on the EPFL campus; it has been tested intensively during a Post-Occupancy Evaluation (POE) study involving twenty human subjects. This study has revealed that the subjects' performance and subjective visual comfort was improved by the new system, compared to

76 FR 47178 - Energy Efficiency Program: Test Procedure for Lighting Systems (Luminaires)

Science.gov (United States)

2011-08-04

... DEPARTMENT OF ENERGY [Docket Number EERE-2011-BT-TP-0041] RIN 1904-AC50 Energy Efficiency Program: Test Procedure for Lighting Systems (Luminaires) AGENCY: Office of Energy Efficiency and Renewable... (``DOE'' or the ``Department'') is currently evaluating energy efficiency test procedures for luminaires...

Niobium Solar Mobile Project — High Strength Niobium Microalloyed Steel as a Solution to Improve Electric Super Scooter and Motorcycle Performance

Science.gov (United States)

Richards, Terry; Kauppi, Erik; Flanagan, Lauren; Ribeio, Eduardo A. A. G.; Nogueira, Marcos A. Stuart; McCourtney, Ian

This paper presents the advantages of replacing mild steel with high strength niobium microalloyed steel in the structure of Electric Super Scooters, Electric Cargo Motorcycles and Solar Charging Stations. The Mini-Fleet-in-a-Box concept was developed by Current Motor to guarantee mobility, efficiency and solar generated electricity. With the adoption of niobium microalloyed high strength steel for more than 90% of the Super Scooter and Motorcycle structures, it was possible to redesign the frame, resulting in a 31% weight reduction and a very modern and functional body. Together with a new powertrain, these changes were responsible for increasing Motorcycle autonomy by more than 15%, depending on average speed. The new frame design reduced the number of high strain points in the frame, increasing the safety of the project. The Solar Charging Station was built using the container concept and designed with high strength niobium microalloyed steel, which resulted in a weight reduction of 25%. CBMM's facility in Araxá, Brazil was selected in the second half of 2013 as the demonstration site to test the efficiency of the Super Scooter and Solar Charging Station. Each Super Scooter has run more than 2,000 km maintenance-free with an autonomy of more than 100 km per charge.

Energy efficient lighting

International Nuclear Information System (INIS)

Aslam, M.

1992-01-01

The main sources of Pakistan's energy supply are oil, natural gas, coal, hydro power, nuclear power and liquefied petroleum gas. At present 75 % of total energy delivered is met through oil and gas. The limited resources and financial constraints have proved to be stumbling block in the way of prosperity and economics stability. Lighting is a conspicuous consumer of energy and thus an easy prey for saving drives which is indeed a very promising target for energy saving. (A.B.)

Energy Efficient LED Spectrally Matched Smart Lighting, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Innovative Imaging and Research and the University of Houston Clear Lake have teamed to develop a widely extensible, affordable, energy efficient, smart lighting...

India : Energy-Efficient Street Lighting--Implementation and Financing Solutions

OpenAIRE

World Bank

2015-01-01

There has been a clear need for energy-efficient (EE) technologies that can be applicable in the municipal street lighting sector. The objective of this manual is to support the preparation and implementation of street lighting projects in India, using performance contracting and other public private partnership-based delivery approaches. This manual draws upon global best practices, inclu...

Transportation Energy Futures Series. Potential for Energy Efficiency Improvement Beyond the Light-Duty-Vehicle Sector

Energy Technology Data Exchange (ETDEWEB)

Vyas, A. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Patel, D. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Bertram, K. M. [Argonne National Lab. (ANL), Argonne, IL (United States)

2013-02-01

Considerable research has focused on energy efficiency and fuel substitution options for light-duty vehicles, while much less attention has been given to medium- and heavy-duty trucks, buses, aircraft, marine vessels, trains, pipeline, and off-road equipment. This report brings together the salient findings from an extensive review of literature on future energy efficiency options for these non-light-duty modes. Projected activity increases to 2050 are combined with forecasts of overall fuel efficiency improvement potential to estimate the future total petroleum and greenhouse gas (GHG) emissions relative to current levels. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Transportation Energy Futures Series: Potential for Energy Efficiency Improvement Beyond the Light-Duty-Vehicle Sector

Energy Technology Data Exchange (ETDEWEB)

Vyas, A. D.; Patel, D. M.; Bertram, K. M.

2013-03-01

Considerable research has focused on energy efficiency and fuel substitution options for light-duty vehicles, while much less attention has been given to medium- and heavy-duty trucks, buses, aircraft, marine vessels, trains, pipeline, and off-road equipment. This report brings together the salient findings from an extensive review of literature on future energy efficiency options for these non-light-duty modes. Projected activity increases to 2050 are combined with forecasts of overall fuel efficiency improvement potential to estimate the future total petroleum and greenhouse gas (GHG) emissions relative to current levels. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Ergonomic study and static analysis for new design of electric scooter

Science.gov (United States)

Fadzly, M. K.; Munirah, Anis; Shayfull, Z.; Saad, Mohd Sazli

2017-09-01

The purposes of this project are to design and diversify the function of a battery powered scooter frame which is more practical for the human factor in ergonomic and optimum design. The new design is based on ideas which are studied from existing scooter frame, United States Patent design and European States International Patent design. The final idea of concept design for scooter frame is based on concept chosen from the best characteristics and it is divided into three main difference ideas and the matrix evaluation method is applied. Analysis that applies to frame design, arm, rim and drive train component is based on Cosmos Express program. As a conclusion, the design that is produce are able to carry the maximum also has more practical features in ergonomic view.

National award for energy-efficient town lighting. Compilation of energy-efficient town lighting techniques; Bundeswettbewerb Energieeffiziente Stadtbeleuchtung. Sammlung energieeffizienter Techniken fuer die Stadtbeleuchtung

Energy Technology Data Exchange (ETDEWEB)

Piller, Sabine; Huebner, Vanessa; Barbre, Felix; Schaefer, Moritz [Berliner Energieagentur GmbH, Berlin (Germany)

2009-02-11

The national award for innovative urban lighting was initiated by the Federal Environmental Office. The resulting publication presents innovative techniques for urban lighting. While it is not a complete market survey, it provides an outline of modern, energy-efficient and environment-friendly technologies that are commercially available. Most systems are also available at comparatively low cost. For more information, interested users should refer to http://www.bmu.de/klimaschutzinitiative/aktuell/41708.php. (orig./AKB)

Red light for Green Paper: The EU policy on energy efficiency

International Nuclear Information System (INIS)

Nilsson, Mats

2007-01-01

The EU Green Paper on energy efficiency calls for action to decrease energy use and thus achieve increased competitiveness, fulfil the environmental targets and increase security of supply. In this comment, we examine the role the EU Commission suggest that energy efficiency, and policies supporting energy efficiency, takes. The policies and the suggestions are qualitatively elaborated upon in the light of the goal of a common European electricity market. We suggest that the rationales for the energy efficiency measures are weak, and that the suggested goals of increased competitiveness, environmental targets, and security of supply are best reached with the direct measures especially designed for each goal. Some of the energy efficiency measures may counter-act other direct policies. Further, The Green Paper measures may prove detrimental to the European Electricity market insofar as the policies suggested could lead to a policy fatigue among the electricity consumers

Lighting energy efficiency in office buildings: Sri Lanka

International Nuclear Information System (INIS)

Wijayatunga, Priyantha D.C.; Fernando, W.J.L.S.; Ranasinghe, S.

2003-01-01

This paper describes a study conducted in the lighting sector of office buildings as a part of a broader research study aimed at developing building codes for Sri Lanka addressing lighting as well as thermal comfort in order to optimise the use of electricity within these buildings. The study covered different tasks performed in office buildings and the optimum lighting levels required to perform these tasks in the office environment in Sri Lanka. Also, it included assessing the visual performance of people involved in different activities under varying illumination levels in a controlled environment and a comparison of these optimum lighting levels with international standards. It can be seen that the required optimum lighting levels are generally lower in Sri Lanka in comparison to specified standard levels, and this scenario is likely to be similar in other developing countries too. These findings clearly emphasise the need to adopt lighting standards most appropriate to local conditions, in turn helping improve the energy efficiency within buildings

Evaluation of energy efficiency in street lighting: model proposition considering climate variability

Directory of Open Access Journals (Sweden)

Amaury Caruzzo

2015-12-01

Full Text Available This paper assesses the impacts of climate variability on efficient electricity consumption in street lighting in Brazil. The Climate Demand Method (CDM was applied, and the energy savings achieved by Brazil’s National Efficient Street Lighting Program (ReLuz in 2005 were calculated, considering the monthly climatology of sunshine duration, disaggregated by county in Brazil. The total energy savings in street lighting in 2005 were estimated at 63 GWh/year or 1.39% higher than the value determined by ReLuz/Eletrobrás and there was a 15 MW reduction in demand in Brazil, considering the nearly 393,000 points in ReLuz served in 2005. The results indicate that, besides the difference in latitude, climate variability in different county increases the daily usage of street lighting up to 19%. Furthermore, Brazil’s large size means that seasonality patterns in energy savings are not homogeneous, and there is a correlation between the monthly variability in sunshine duration and the latitude of mesoregions. The CDM was also shown to be suitable for ranking mesoregions with the highest levels of energy saving lighting.

Wireless sensor and actuator networks for lighting energy efficiency and user satisfaction

Science.gov (United States)

Wen, Yao-Jung

Buildings consume more than one third of the primary energy generated in the U.S., and lighting alone accounts for approximately 30% of the energy usage in commercial buildings. As the largest electricity consumer of all building electrical systems, lighting harbors the greatest potential for energy savings in the commercial sector. Fifty percent of current energy consumption could be reduced with energy-efficient lighting management strategies. While commercial products do exist, they are poorly received due to exorbitant retrofitting cost and unsatisfactory performance. As a result, most commercial buildings, especially legacy buildings, have not taken advantage of the opportunity to generate savings from lighting. The emergence of wireless sensor and actuator network (WSAN) technologies presents an alternative that circumvents costly rewiring and promises better performance than existing commercial lighting systems. The goal of this dissertation research is to develop a framework for wireless-networked lighting systems with increased cost effectiveness, energy efficiency, and user satisfaction. This research is realized through both theoretical developments and implementations. The theoretical research aims at developing techniques for harnessing WSAN technologies to lighting hardware and control strategies. Leveraging redundancy, a sensor validation and fusion algorithm is developed for extracting pertinent lighting information from the disturbance-prone desktop-mounted photosensors. An adaptive sensing strategy optimizes the timing of data acquisition and power-hungry wireless transmission of sensory feedback in real-time lighting control. Exploiting the individual addressability of wireless-enabled luminaires, a lighting optimization algorithm is developed to create the optimal lighting that minimizes energy usage while satisfying occupants' diverse lighting preferences. The wireless-networked lighting system was implemented and tested in a number of real

A nano-graphite cold cathode for an energy-efficient cathodoluminescent light source

Directory of Open Access Journals (Sweden)

Alexander N. Obraztsov

2013-08-01

Full Text Available The development of new types of light sources is necessary in order to meet the growing demands of consumers and to ensure an efficient use of energy. The cathodoluminescence process is still under-exploited for light generation because of the lack of cathodes suitable for the energy-efficient production of electron beams and appropriate phosphor materials. In this paper we propose a nano-graphite film material as a highly efficient cold cathode, which is able to produce high intensity electron beams without energy consumption. The nano-graphite film material was produced by using chemical vapor deposition techniques. Prototypes of cathodoluminescent lamp devices with a construction optimized for the usage of nano-graphite cold cathodes were developed, manufactured and tested. The results indicate prospective advantages of this type of lamp and the possibility to provide advanced power efficiency as well as enhanced spectral and other characteristics.

Connected Lighting Systems Efficiency Study$-$ PoE Cable Energy Losses, Part 1

Energy Technology Data Exchange (ETDEWEB)

Tuenge, Jason [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kelly, Karsten [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poplawski, Michael [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2017-11-30

First report in a study of the efficiency of connected lighting systems. The report summarizes the results of an exploratory study investigating power losses in Ethernet cables used between PoE switches and luminaires in PoE connected lighting systems. Testing was conducted at the Pacific Northwest National Laboratory (PNNL) Connected Lighting Test Bed in September 2017. The results were analyzed to explore the impact of cable selection on PoE lighting system energy efficiency, as well as the effectiveness of guidelines recently introduced by the American National Standards Institute (ANSI) C137 Lighting Systems Committee.

De duurzaamste scooter komt uit Delft’, Inholland Composietenlab

NARCIS (Netherlands)

Antoine Gerritse

2014-01-01

Het Inholland composietenlab en MKB-bedrijven hebben de duurzaamste scooter ter wereld ontwikkeld. De dragende constructie is gemaakt van lichtgewicht en extreem sterk composiet dat bestaat uit Nederlands vlas en natuurlijk harsen.

Manoeuvring space for electric wheelchairs and scooters

NARCIS (Netherlands)

van der Voordt, D.J.M.; de Jong, G.E.; Verkroost, S.

1996-01-01

To be universally accessible the built environment must be adequately adapted to the needs of the widest possible range of users and to the use of mobility aids such as walking sticks, rollator walkers, manual wheelchairs and electric scooters. Delft University of Technology regularly conducts

Should visually impaired people drive slow motorised vehicles? : Evaluation of driving safety in mobility scooters

NARCIS (Netherlands)

Cordes, Christina; Melis-Dankers, Bart; Heutink, Joost; Brookhuis, Karel; Brouwer, Wiebo

2015-01-01

Background: Mobility scooters may help people with motor impairments maintain independent mobility. However, many users have comorbid disorders that can influence their ability to drive safely. Over the past few years, the media have drawn much attention to mobility scooter safety. Visual disorders

Energy efficient lighting in the residences of staff of the University of ...

African Journals Online (AJOL)

CFL) as an energy-efficient lighting system. The results of the study show that even though academics in the university have received information about the use of CFLs as a way of saving energy, very few show interest in their use. It is inferred ...

The impact of mobility scooters on their users. Does their usage help or hinder?: A state of the art review.

Science.gov (United States)

Thoreau, Roselle

2015-06-01

As older people start to have difficulty in walking many choose to use a mobility scooter to help them move around. Benefitting from improved design, mobility scooters are becoming an increasingly popular mobility device and are a common sight on many streets. However, very little is known about their usage or their impact in terms of either quality of life or functional health. Whilst mobility scooters may help to improve the quality of life of their users, it is also possible that the sedentary nature of their usage results in a decline of physical functionality and therefore reduced capabilities. Before any substantial research can be carried out it is crucial to understand the importance of a mobility scooter on the lives of the people that use them and to review the initial research published on the effect of scooter use on physical health. This paper is a state-of-the-art review. It describes the current research knowledge on mobility scooters, shows where gaps in knowledge exist and where future research needs to focus.

Energy efficient lighting and controls at North Lanarkshire Council: Good practice case study

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-11-15

The Sir Matt Busby Sports Complex is an important local facility for the people of Bellshill, North Lanarkshire. The sports and leisure complex, a North Lanarkshire Council property, offers a combination of indoor and outdoor sporting facilities including a floodlit synthetic football pitch and a comprehensive mix of swimming, sauna, gym and sports hall facilities. The electrical demand imposed by lighting for any business can be very significant, constituting up to 30% of the electrical power consumption. At the Sir Matt Busby Sports Complex a combination of new efficient light fittings and controls has improved lighting levels, reduced overall energy consumption by nearly 10% and provided substantial cost savings. The Carbon Trust has assisted the Council by identifying and prioritising energy saving opportunities and providing a prioritised implementation plan. This partnership arrangement and the Council's access to UK Pound 930,000 of 'spend to save' funding, provided by the Scottish Executive, has allowed the rapid implementation of energy efficiency measures. (GB)

Industrial energy efficiency in light of climate change negotiations: Comparing major developing countries and the U.S

International Nuclear Information System (INIS)

Phylipsen, D.; Price, L.; Worrell, E.; Blok, K.

1999-01-01

In light of the commitments accepted within the Framework Convention on Climate Change there is an increasing need for useful information on energy consumption and energy efficiency. Governments can use this information in designing policies to reduce greenhouse gas emissions and prioritizing energy savings options. International comparison of energy efficiency can provide a benchmark against which a country's performance can be measured and policies can be evaluated. A methodology for international comparisons of industrial energy efficiency was developed by the International Network on Energy Demand analysis in the Industrial Sector. In this paper this methodology is used to analyze the energy efficiency of two energy-intensive industries in major developing countries. Energy consumption trends are shown for the steel and cement industry and an analysis is made of technologies used. In light of the Byrd-Hagel resolution, which states that the US will not ratify any climate treaty unless it also mandates commitments to limit greenhouse gas emissions for developing countries, the energy efficiency in the two sectors is compared to that of the US. The analysis shows that in the iron and steel sector South Korea and Brazil are more energy-efficient than the US, while Mexico has achieved a comparable energy efficiency level in recent years. For cement, South Korea, Brazil and Mexico are the most efficient countries analyzed. In recent years, China, and especially, India appear to have achieved energy efficiency levels, more or less comparable to that of the US. In light of data constraints, however, further analysis is required

Scooter Leasing : A Cradle-to-Cradle Sound Strategy?

NARCIS (Netherlands)

Peters, F.H.J.; De Brito, M.P.

2010-01-01

This article investigates the application of the Cradle-to-Cradle approach to the electric scooter vehicle, and how the concept of leasing can be used as a means to make it operational. This research is a result of a research project with Eco-Movement, a Dutch firm currently selling electric

Energy efficiency effect on the public street lighting by using LED light replacement and kwh-meter installation at DKI Jakarta Province, Indonesia

Science.gov (United States)

Sudarmono, Panggih; Deendarlianto; Widyaparaga, Adhika

2018-05-01

Public street lighting consumes large energy for the public interest, but many street lights still do not use energy-saving technologies. In 2014, Provincial Government of DKI Jakarta operated 179,305 units of street lights. Of the number of installed armature, 92 % of them or 166,441 units are HPS (High-Pressure Sodium) armatures which are inefficient. In 2016, the Provincial Government of DKI Jakarta cut down the energy used for street lighting, by implementing the programs of kWh-meter installation in every street lighting panel and use energy-saving lamps equipped with the smart system. The Provincial Government of DKI Jakarta is registered with 6,399 customer IDs in PLN (State Owned Electric Company), and gradually carried out the kWh Meter installation and changes to the contract. The program to use energy-saving lights done by replacing the HPS armature that is not energy efficient to LED armature which is known to be energy efficient. Until the end of 2016, the number of armatures that has been replaced was 89,417 units. The research results on 25 samples of PLN customer IDs and the replacement of 2,162 units armature, showed that the energy efficiency through kWh meter installation and armature replacement reduce the power consumption from 330,414 kWh to 71,278 kWh or by 78.43%. Generally, there was a decrease in the value of electricity bill compared to the before the replacement. The program of kWh-meter installations and replacement of the armature has a payback period of 2.66 years.

High Performance and Energy Efficient Traffic Light Controller Design Using FPGA

DEFF Research Database (Denmark)

Pandey, Sujeet; Shrivastav, Vivek Kumar; Sharma, Rashmi

2017-01-01

and then we have analyzed power consumption for traffic light controller on different FPGA. Leakage power is in range of 97.5-99% of total power consumption by traffic light controller on Virtex-7 FPGA. Signal power, clock power and IOs power are almost negligible. Power dissipation is measured on XPOWER......In this work, Verilog is used as hardware description language for implementation of traffic light controller. It shows Red, Green and Yellow color at a predefined interval. Technology scaling is used as energy efficient technique. We have used 90nm, 65nm, 40nm and 28nm technology based FPGA...

Analysis of federal policy options for improving US lighting energy efficiency: Commercial and residential buildings

Energy Technology Data Exchange (ETDEWEB)

Atkinson, B.A.; McMahon, J.E.; Mills, E.; Chan, P.; Chan, T.W.; Eto, J.H.; Jennings, J.D.; Koomey, J.G.; Lo, K.W.; Lecar, M.; Price, L.; Rubinstein, F.; Sezgen, O.; Wenzel, T.

1992-12-01

The US Department of Energy (DOE) has recognized the opportunity to achieve energy, economic, and environmental benefits by promoting energy-efficient lighting through federal policies, including lighting standards, financial incentives, and information programs. To assist in this process, the Office of Conservation and Renewable Energy`s Office of Codes and Standards invited Lawrence Berkeley Laboratory to assess prospective national impacts for a variety of policy options. Some progress has already been made in developing lighting policies at both the federal and state levels. The US DOE`s Office of Building Technologies has evaluated lighting efficiency incentives as part of its analysis for the National Energy Strategy. Fluorescent and incandescent lamp standards are included in the national Energy Policy Act of 1992 (P.L. 102-486, October 24, 1992). A few states have analyzed or implemented lamp and luminaire standards. Many policy-related issues merit further investigation. For example, there is considerable debate over issues such as mandatory or voluntary standards versus component labeling and other education-oriented strategies. Several different technologies are involved that interact with each other-lamps (incandescent, compact fluorescent, and HID), ballasts (for fluorescent and HID lamps), and fixtures with reflectors and lenses. Control systems and operation patterns must also be considered (timers, automated dimming, or occupancy sensors). Lighting applications are diverse, ranging from offices, restaurants, hallways, hospital operating rooms, to exterior lights. Lighting energy use influences heating and cooling requirements in buildings. Successful lighting system design must also address interactions between architectural design elements and daylighting availability. Proper system installation and ongoing operation and maintenance are crucial. The economic aspects of the preceding points must also be considered for policy making.

New rules of thumb maximizing energy efficiency in street lighting with discharge lamps: The general equations for lighting design

Science.gov (United States)

Peña-García, A.; Gómez-Lorente, D.; Espín, A.; Rabaza, O.

2016-06-01

New relationships between energy efficiency, illuminance uniformity, spacing and mounting height in public lighting installations were derived from the analysis of a large sample of outputs generated with a widely used software application for lighting design. These new relationships greatly facilitate the calculation of basic lighting installation parameters. The results obtained are also based on maximal energy efficiency and illuminance uniformity as a premise, which are not included in more conventional methods. However, these factors are crucial since they ensure the sustainability of the installations. This research formulated, applied and analysed these new equations. The results of this study highlight their usefulness in rapid planning and urban planning in developing countries or areas affected by natural disasters where engineering facilities and computer applications for this purpose are often unavailable.

Energy Efficiency Comparison between Compact Fluorescent Lamp and Common Light Bulb

Science.gov (United States)

Tanushevsk, Atanas; Rendevski, Stojan

2016-01-01

For acquainting the students of applied physics and students of teaching physics with the concept of energy efficiency, electrical and spectral characteristics of two widely used lamps--integrated fluorescence lamp and common light bulb have been investigated. Characterization of the lamps has been done by measuring the spectral irradiance and…

Light vehicle energy efficiency programs and their impact on Brazilian CO2 emissions

International Nuclear Information System (INIS)

Wills, William; La Rovere, Emilio Lebre

2010-01-01

This paper analyses the impact of an energy efficiency program for light vehicles in Brazil on emissions of carbon dioxide (CO 2 ), the main greenhouse gas in the atmosphere. Several energy efficiency programs for light vehicles around the world are reviewed. The cases of Japan and Europe were selected for presentation here given their status as current and future world leaders in the control of passenger vehicle fuel consumption. The launching of the National Climate Change Plan and the pressure on the Brazilian car industry due to the world financial crisis make it a good time for the Brazilian government to implement such a program, and its various benefits are highlighted in this study. Three scenarios are established for Brazil covering the 2000-2030 period: the first with no efficiency goals, the second with the Japanese goals applied with a 10 years delay, and the third, with the Japanese goals applied with no delay. The consequences of a vehicular efficiency program and its middle and long-term effects on the consumption of energy and the CO 2 emissions are quantified and discussed. The simulation results indicate that efficiency goals may make an important contribution to reducing vehicular emissions and fuel consumption in Brazil, compared to a baseline scenario.

The efficiency, energy intensity and visual impact of the accent lighting in the retail grocery stores

Directory of Open Access Journals (Sweden)

Ľudmila Nagyová

2014-11-01

Full Text Available Over the last few years, topics of displaying, presentation, lighting, energy saving and issues related to the environment while selling the fresh food (fruits, vegetable, bakery products, meat are becoming an important matter among traders. However, just bigger companies with transnational capital have devoted their attention to this issue yet. Generally, the energy costs make up 70% of operating costs in retail stores where the cooling system and lighting are the most energy consuming. Accent lighting in modern retails is largely involved in the overall design and atmosphere in shops and plays a crucial role in presenting the goods as well. Using of accent lighting can draw the customer's attention to a specific part of the sales area and achieve the overall harmonization in the store. With the rational using of combination of energy saving and effective accent lighting retailers can achieve not only attractive presentation of displayed products but also appreciable savings in the operation of their stores. It is the only factor that can be exactly measured and controlled. Using a Colour and Lux Meters we found out the intensity and color temperature of accent lighting used in domestic and foreign retail chains for the different kinds of fresh food products. Based on the obtained values we have compiled graphs, which are showing visual comfort. We also identified different types of accent lighting, which we assigned to their impact on emotional involvement of consumers. The starting points were the tests we conducted in simulated laboratory conditions. While searching of a compromise between effective and energy efficient accent lighting we take into consideration consumers' emotional response as well as the annual electricity consumption of different types of light sources. At the end we recommend options for energy-efficient, effective and spectacular lighting while using the optimal number of light sources and their logical organization

New energy technologies 4. Energy management and energy efficiency

International Nuclear Information System (INIS)

Sabonnadiere, J.C.; Caire, R.; Raison, B.; Quenard, D.; Verneau, G.; Zissis, G.

2007-01-01

This forth tome of the new energy technologies handbook is devoted to energy management and to the improvement of energy efficiency. The energy management by decentralized generation insertion and network-driven load control, analyzes the insertion and management means of small power generation in distribution networks and the means for load management by the network with the aim of saving energy and limiting peak loads. The second part, devoted to energy efficiency presents in a detailed way the technologies allowing an optimal management of energy in buildings and leading to the implementation of positive energy buildings. A special chapter treats of energy saving using new lighting technologies in the private and public sectors. Content: 1 - decentralized power generation - impacts and solutions: threat or opportunity; deregulation; emerging generation means; impact of decentralized generation on power networks; elements of solution; 2 - mastery of energy demand - loads control by the network: stakes of loads control; choice of loads to be controlled; communication needs; measurements and controls for loads control; model and algorithm needs for loads control. A better energy efficiency: 3 - towards positive energy buildings: key data for Europe; how to convert fossil energy consuming buildings into low-energy consuming and even energy generating buildings; the Minergie brand; the PassivHaus or 'passive house' label; the zero-energy house/zero-energy home (ZEH); the zero-energy building (ZEB); the positive energy house; comparison between the three Minergie/PassivHaus/ZEH types of houses; beyond the positive energy building; 4 - light sources and lighting systems - from technology to energy saving: lighting yesterday and today; light sources and energy conversion; energy saving in the domain of lighting: study of some type-cases; what future for light sources. (J.S.)

Analysis of federal policy options for improving US lighting energy efficiency: Commercial and residential buildings

Energy Technology Data Exchange (ETDEWEB)

Atkinson, B.A.; McMahon, J.E.; Mills, E.; Chan, P.; Chan, T.W.; Eto, J.H.; Jennings, J.D.; Koomey, J.G.; Lo, K.W.; Lecar, M.; Price, L.; Rubinstein, F.; Sezgen, O.; Wenzel, T.

1992-12-01

The US Department of Energy (DOE) has recognized the opportunity to achieve energy, economic, and environmental benefits by promoting energy-efficient lighting through federal policies, including lighting standards, financial incentives, and information programs. To assist in this process, the Office of Conservation and Renewable Energy's Office of Codes and Standards invited Lawrence Berkeley Laboratory to assess prospective national impacts for a variety of policy options. Some progress has already been made in developing lighting policies at both the federal and state levels. The US DOE's Office of Building Technologies has evaluated lighting efficiency incentives as part of its analysis for the National Energy Strategy. Fluorescent and incandescent lamp standards are included in the national Energy Policy Act of 1992 (P.L. 102-486, October 24, 1992). A few states have analyzed or implemented lamp and luminaire standards. Many policy-related issues merit further investigation. For example, there is considerable debate over issues such as mandatory or voluntary standards versus component labeling and other education-oriented strategies. Several different technologies are involved that interact with each other-lamps (incandescent, compact fluorescent, and HID), ballasts (for fluorescent and HID lamps), and fixtures with reflectors and lenses. Control systems and operation patterns must also be considered (timers, automated dimming, or occupancy sensors). Lighting applications are diverse, ranging from offices, restaurants, hallways, hospital operating rooms, to exterior lights. Lighting energy use influences heating and cooling requirements in buildings. Successful lighting system design must also address interactions between architectural design elements and daylighting availability. Proper system installation and ongoing operation and maintenance are crucial. The economic aspects of the preceding points must also be considered for policy making.

Energy efficiency opportunities in Hotels

Directory of Open Access Journals (Sweden)

Dina Said

2017-03-01

Full Text Available According to the statistics in Egypt (2013, the number of hotels is 1193, about 407 of them have contracted power greater than 500 kW.Air conditioning, lighting, water heating and refrigeration represent the main activities demanding electrical energy in hotel business.The energy consumption per night spend changes a lot, depending on various factors; facilities provided, category of hotel, occupancy , geographical situation, weather conditions, nationality of clients, design and control of the installations.Energy benchmarking is an internal management tool designed to provide ongoing, reliable and verifiable tracking on the hotels performance. The most useful performance indicator (or Energy Efficiency Benchmarking of hotels are: Lighting Power Density (LPD in W (for lighting/m2, and energy intensity (kWh/m2/ y.There are multiple benefits for improving energy in hotel business; reduces the hotel's operating cost, reduces climate change risks and promotes green tourism.Energy efficiency opportunities are low-cost measures and cost- effective investments.   There are many energy saving opportunities for lighting in hotel's guest rooms as well as the more obvious savings in lobbies and exterior lighting areas. Behavior campaigns can yield substantial energy savings, both through the guests and housekeeper behavior. Encouraging housekeepers to use natural light during room cleaning is a simple first step to implement energy saving program.This paper presents the energy efficiency guidelines and energy benchmarking for hotels. Also a case study showing how the energy efficiency program implemented is presented. 

Design and simulation of a lithium-ion battery with a phase change material thermal management system for an electric scooter

Science.gov (United States)

Khateeb, Siddique A.; Farid, Mohammed M.; Selman, J. Robert; Al-Hallaj, Said

A lithium-ion battery employing a novel phase change material (PCM) thermal management system was designed for an electric scooter. Passive thermal management systems using PCM can control the temperature excursions and maintain temperature uniformity in Li-ion batteries without the use of active cooling components such as a fan, a blower or a pump found in air/liquid-cooling systems. Hence, the advantages of a compact, lightweight, and energy efficient system can be achieved with this novel form of thermal management system. Simulation results are shown for a Li-ion battery sub-module consisting of nine 18650 Li-ion cells surrounded by PCM with a melting point between 41 and 44 °C. The use of aluminum foam within the PCM and fins attached to the battery module were studied to overcome the low thermal conductivity of the PCM and the low natural convection heat transfer coefficient. The comparative results of the PCM performance in the presence of Al-foam and Al-fins are shown. The battery module is also simulated for summer and winter conditions. The effect of air-cooling on the Li-ion battery was also studied. These simulation results demonstrate the successful use of the PCM as a potential candidate for thermal management solution in electric scooter applications and therefore for other electric vehicle applications.

A simple and accurate model for the design of public lighting with energy efficiency functions based on regression analysis

International Nuclear Information System (INIS)

Rabaza, Ovidio; Gómez-Lorente, Daniel; Pérez-Ocón, Francisco; Peña-García, Antonio

2016-01-01

In this study, new relationships between the energy efficiency of street lighting systems, street width, and luminaire height were derived from the analysis of a large sample of outputs, generated with a software application widely used for lighting design. The result was a quadratic polynomial that perfectly fit the relationships obtained and whose coefficients characterize each type of luminaire. This greatly simplifies the design of lighting facilities because it only uses one equation, but at the same time, takes all necessary variables into account. The procedure maximized the energy efficiency of the street lighting systems, as far as conditions allowed, and greatly facilitated the calculation of the parameters of a basic lighting installation, according to CIE (International Commission on Illumination) recommendations. - Highlights: • New parameter relationships for efficient public lighting design were obtained. • A second-order polynomial simplifies the design of the lighting facilities using only one equation. • The procedure guarantees the maximization of energy efficiency of street lighting systems. • The results have been successfully tested with a well-known and reliable free software.

Recycled Thermal Energy from High Power Light Emitting Diode Light Source.

Science.gov (United States)

Ji, Jae-Hoon; Jo, GaeHun; Ha, Jae-Geun; Koo, Sang-Mo; Kamiko, Masao; Hong, JunHee; Koh, Jung-Hyuk

2018-09-01

In this research, the recycled electrical energy from wasted thermal energy in high power Light Emitting Diode (LED) system will be investigated. The luminous efficiency of lights has been improved in recent years by employing the high power LED system, therefore energy efficiency was improved compared with that of typical lighting sources. To increase energy efficiency of high power LED system further, wasted thermal energy should be re-considered. Therefore, wasted thermal energy was collected and re-used them as electrical energy. The increased electrical efficiency of high power LED devices was accomplished by considering the recycled heat energy, which is wasted thermal energy from the LED. In this work, increased electrical efficiency will be considered and investigated by employing the high power LED system, which has high thermal loss during the operating time. For this research, well designed thermoelement with heat radiation system was employed to enhance the collecting thermal energy from the LED system, and then convert it as recycled electrical energy.

Optimal sampling plan for clean development mechanism energy efficiency lighting projects

International Nuclear Information System (INIS)

Ye, Xianming; Xia, Xiaohua; Zhang, Jiangfeng

2013-01-01

Highlights: • A metering cost minimisation model is built to assist the sampling plan for CDM projects. • The model minimises the total metering cost by the determination of optimal sample size. • The required 90/10 criterion sampling accuracy is maintained. • The proposed metering cost minimisation model is applicable to other CDM projects as well. - Abstract: Clean development mechanism (CDM) project developers are always interested in achieving required measurement accuracies with the least metering cost. In this paper, a metering cost minimisation model is proposed for the sampling plan of a specific CDM energy efficiency lighting project. The problem arises from the particular CDM sampling requirement of 90% confidence and 10% precision for the small-scale CDM energy efficiency projects, which is known as the 90/10 criterion. The 90/10 criterion can be met through solving the metering cost minimisation problem. All the lights in the project are classified into different groups according to uncertainties of the lighting energy consumption, which are characterised by their statistical coefficient of variance (CV). Samples from each group are randomly selected to install power meters. These meters include less expensive ones with less functionality and more expensive ones with greater functionality. The metering cost minimisation model will minimise the total metering cost through the determination of the optimal sample size at each group. The 90/10 criterion is formulated as constraints to the metering cost objective. The optimal solution to the minimisation problem will therefore minimise the metering cost whilst meeting the 90/10 criterion, and this is verified by a case study. Relationships between the optimal metering cost and the population sizes of the groups, CV values and the meter equipment cost are further explored in three simulations. The metering cost minimisation model proposed for lighting systems is applicable to other CDM projects as

Productivity and energy efficiency

Energy Technology Data Exchange (ETDEWEB)

Lovins, H. [Rocky Mountain Inst., Snowmass, CO (United States)

1995-12-31

Energy efficient building and office design offers the possibility of significantly increased worker productivity. By improving lighting, heating and cooling, workers can be made more comfortable and productive. An increase of 1 percent in productivity can provide savings to a company that exceed its entire energy bill. Efficient design practices are cost effective just from their energy savings. The resulting productivity gains make them indispensable. This paper documents eight cases in which efficient lighting, heating, and cooling have measurably increased worker productivity, decreased absenteeism, and/or improved the quality of work performed. They also show that efficient lighting can measurably increase work quality by removing errors and manufacturing defects. The case studies presented include retrofit of existing buildings and the design of new facilities, and cover a variety of commercial and industrial settings. Each case study identifies the design changes that were most responsible for increased productivity. As the eight case studies illustrate, energy efficient design may be one of the least expensive ways for a business to improve the productivity of its workers and the quality of its product. (author). 15 refs.

Light vehicle energy efficiency programs and their impact on Brazilian CO{sub 2} emissions

Energy Technology Data Exchange (ETDEWEB)

Wills, William; La Rovere, Emilio Lebre [Centro de Estudos Integrados sobre Meio Ambiente e Mudancas Climaticas, Centro Clima/COPPE/UFRJ, Centro de Tecnologia, Bloco I2000, sala 208, Cidade Universitaria, Ilha do Fundao, CEP: 21941-972 Rio de Janeiro, RJ (Brazil)

2010-11-15

This paper analyses the impact of an energy efficiency program for light vehicles in Brazil on emissions of carbon dioxide (CO{sub 2}), the main greenhouse gas in the atmosphere. Several energy efficiency programs for light vehicles around the world are reviewed. The cases of Japan and Europe were selected for presentation here given their status as current and future world leaders in the control of passenger vehicle fuel consumption. The launching of the National Climate Change Plan and the pressure on the Brazilian car industry due to the world financial crisis make it a good time for the Brazilian government to implement such a program, and its various benefits are highlighted in this study. Three scenarios are established for Brazil covering the 2000-2030 period: the first with no efficiency goals, the second with the Japanese goals applied with a 10 years delay, and the third, with the Japanese goals applied with no delay. The consequences of a vehicular efficiency program and its middle and long-term effects on the consumption of energy and the CO{sub 2} emissions are quantified and discussed. The simulation results indicate that efficiency goals may make an important contribution to reducing vehicular emissions and fuel consumption in Brazil, compared to a baseline scenario. (author)

Energy efficient lighting design for Venlo type greenhouses

NARCIS (Netherlands)

Janssen, E.G.O.N.; Zonneveldt, L.; Sools, F.

2005-01-01

TNO has developed a Radiance software model to calculate the light distribution in the greenhouse using raytracing methods, suitable for daylight and artificial lighting. The model is based on a 3d CAD model. The objective is to maximize the efficiency of the artificial lighting system (the amount

Energy efficiency of lighting systems in residential buildings; Energieeffizienzsteigerung der Beleuchtungstechnik in Wohngebaeuden

Energy Technology Data Exchange (ETDEWEB)

Troeger, Andreas [Technische Univ. Dresden (Germany). Elektrotechnisches Inst.; Wittig, Michael; Schlosser, Roman; Wuerfel, Matthias [Westsaechsische Hochschule Zwickau (Germany). Fakultaet Elektrotechnik

2011-07-01

Due to political demands such as the law of an eco-friendly-design of Energy Using Products (EBPG), the production and thus the long-term use of conventional light bulbs is no longer possible within the European Union. Energy saving light bulbs are preferred as replacement for those bulbs. However, these lighting systems have unfavourable properties for certain areas of applications, such as low luminance during the heating phase or a low lifetime if used under strongly fluctuating stress. Therefore, using conventional light bulbs in stairwells, their properties are of great disadvantage. The paper examines possible applications for LED lighting systems (Light Emitting Diode), meeting the standards. Investigations of possible on-demand switching or dimming of LED lighting have been executed with the help of presence or movement sensors and by using smart grids such as the KNX-compliant components. Furthermore, technical requirements, economic viability and energetic advantages and disadvantages of separate DC power networks for the operating of the LED lights have been tested. Since energy storage increased in rental buildings, the storage system DC supply can be used for DC power of such consumers. In this way, the AC and the rectifier losses can be avoided and thus the energy efficiency of lighting can be increased in rental buildings. To implement the project a model of a staircase has been created by using the simulation software DIALux. Furthermore the given lighting conditions have been measured in the stairwell. Thus, the staircase model yields comparative results. (orig.)

Motorcycle and scooter speeds approaching urban intersections.

Science.gov (United States)

Walton, D; Buchanan, J

2012-09-01

Five urban, uncontrolled T-intersections known to be motorcycle crash 'black spots' were monitored using instrumentation and a roadside observer. Two sets of twelve-hour observations were collected for each site (N≈100,000). Instrumentation recorded the 'events' of vehicles passing to measure, speed, direction, lane position, vehicle type (broadly characterised) and headway. Observers further recorded times of bicycle events, type of motorcycle (scooters or motorcycles), the behaviour of motorcycles and the use of 'high conspicuity' gear such as clothing or helmets. Results establish that motorcycles travel around 10% faster than the other traffic (car mean speed=34.97 km/h), with motorcycles travelling on average 3.3 km/h faster than cars. Motorcycles were 3.4 times more likely to be exceeding the speed limit than cars. Similar results are described for scooters. Also examined are the influences on mean speeds such as the time of day, the presence of a car at the t-intersection, and the influence of free headway. The results are compared for robustness across locations and days. It is concluded that in urban areas motorcycles are travelling significantly faster than other traffic. These findings are discussed against a concern to reduce motorcycle crashes by improving conspicuity and previous research that implicates a 'looked-but-failed-to-see' effect for car drivers. Copyright © 2012 Elsevier Ltd. All rights reserved.

Light energy partitioning, photosynthetic efficiency and biomass allocation in invasive Prunus serotina and native Quercus petraea in relation to light environment, competition and allelopathy.

Science.gov (United States)

Robakowski, Piotr; Bielinis, Ernest; Sendall, Kerrie

2018-05-01

This study addressed whether competition under different light environments was reflected by changes in leaf absorbed light energy partitioning, photosynthetic efficiency, relative growth rate and biomass allocation in invasive and native competitors. Additionally, a potential allelopathic effect of mulching with invasive Prunus serotina leaves on native Quercus petraea growth and photosynthesis was tested. The effect of light environment on leaf absorbed light energy partitioning and photosynthetic characteristics was more pronounced than the effects of interspecific competition and allelopathy. The quantum yield of PSII of invasive P. serotina increased in the presence of a competitor, indicating a higher plasticity in energy partitioning for the invasive over the native Q. petraea, giving it a competitive advantage. The most striking difference between the two study species was the higher crown-level net CO 2 assimilation rates (A crown ) of P. serotina compared with Q. petraea. At the juvenile life stage, higher relative growth rate and higher biomass allocation to foliage allowed P. serotina to absorb and use light energy for photosynthesis more efficiently than Q. petraea. Species-specific strategies of growth, biomass allocation, light energy partitioning and photosynthetic efficiency varied with the light environment and gave an advantage to the invader over its native competitor in competition for light. However, higher biomass allocation to roots in Q. petraea allows for greater belowground competition for water and nutrients as compared to P. serotina. This niche differentiation may compensate for the lower aboveground competitiveness of the native species and explain its ability to co-occur with the invasive competitor in natural forest settings.

Performance of the mixed LED light quality on the growth and energy efficiency of Arthrospira platensis.

Science.gov (United States)

Mao, Ruixin; Guo, Shuangsheng

2018-06-01

The effect of mixed light quality with red, blue, and green LED lamps on the growth of Arthrospira platensis was studied, so as to lay the theoretical and technical basis for establishing a photo-bioreactor lighting system for application in space. Meanwhile, indexes, like morphology, growth rate, photosynthetic pigment compositions, energy efficiency, and main nutritional components, were measured respectively. The results showed that the blue light combined with red light could decrease the tightness of filament, and the effect of green light was opposite. The combination of blue light or green light with red light induced the filaments to get shorter in length. The 8R2B treatment could promote the growth of Arthrospira platensis significantly, and its dry weight reached 1.36 g L -1 , which was 25.93% higher than the control. What's more, 8R2B treatment had the highest contents of carbohydrate and lipid, while 8R2G was rich in protein. 8R0.5G1.5B had the highest efficiency of biomass production, which was 161.53 mg L -1  kW -1  h -1 . Therefore, the combination of red and blue light is more conducive to the growth of Arthrospira platensis, and a higher biomass production and energy utilization efficiency can be achieved simultaneously under the mixed light quality with the ratio of 8R0.5G1.5B.

Towards Hybrid Urban Mobility: Kick Scooter as a Means of Individual Transport in the City

Science.gov (United States)

Kostrzewska, Małgorzata; Macikowski, Bartosz

2017-10-01

The characteristic feature of a contemporary city is its inconvenience and oppressiveness caused by the hitherto dominant paradigm of urban planning based on car mobility. As a result, the inhabitants have to cope with air pollution, noise, spatial barriers, sedentary lifestyle and other factors which worsen their health and quality of life. Ecological and physically activating urban mobility thus plays an increasingly important role in the process of creating a friendly and healthy city. For many years, a steadily increasing share of bicycles in urban traffic has been observed. There are also other trending forms of non-motorized transport, such as in-line skates, skateboards, kick scooters, etc. Riding each of them can be regarded as a form of recreation or sport, but also as an ecological, physically activating means of urban mobility. The paper discusses the different forms of recreational mobility in the context of the possibility of combining it with city public transport, with particular emphasis on kick scooters. Kick scooters are becoming more and more popular, not only among children and youth, but also among adults, who use it mainly as a means of the non-motorised urban transport. Numerous publications from different parts of the world show a dynamic growth of this phenomenon. The aim of the article is also to answer the question in what extent the design of public space takes into consideration the use of these new forms of transport and recreation and, consequently, what aspects and requirements should be taken into account in the planning and design process. The paper presents the conclusions of a field study carried out with a group of students in Szczecin and Berlin. The aim of the research was to evaluate the possibilities of using kick scooters in big cities as a means of hybrid mobility combined with public transport by exploring the spectrum of public spaces (streets, squares, traffic nodes and hubs, public buildings, etc.) and testing the

Solar-energy production and energy-efficient lighting: photovoltaic devices and white-light-emitting diodes using poly(2,7-fluorene), poly(2,7-carbazole), and poly(2,7-dibenzosilole) derivatives.

Science.gov (United States)

Beaupré, Serge; Boudreault, Pierre-Luc T; Leclerc, Mario

2010-02-23

World energy needs grow each year. To address global warming and climate changes the search for renewable energy sources with limited greenhouse gas emissions and the development of energy-efficient lighting devices are underway. This Review reports recent progress made in the synthesis and characterization of conjugated polymers based on bridged phenylenes, namely, poly(2,7-fluorene)s, poly(2,7-carbazole)s, and poly(2,7-dibenzosilole)s, for applications in solar cells and white-light-emitting diodes. The main strategies and remaining challenges in the development of reliable and low-cost renewable sources of energy and energy-saving lighting devices are discussed.

Consumer preferences and willingness to pay for compact fluorescent lighting: Policy implications for energy efficiency promotion in Saint Lucia

International Nuclear Information System (INIS)

Reynolds, Travis; Kolodinsky, Jane; Murray, Byron

2012-01-01

This article examines consumer willingness to pay for energy-saving compact fluorescent light bulbs using the results of a stated preferences study conducted in the Caribbean island nation of Saint Lucia. Geographic location, low income status, and age are found to affect willingness-to-pay for compact fluorescent lighting, while higher income status and other demographic variables appear to have minimal or no significant impacts. Energy efficiency knowledge is associated with increased willingness-to-pay for energy-efficient bulbs and with increased use of compact fluorescent lighting. Contrary to theoretical expectations, past purchase of compact fluorescent bulbs is found to have no impact on self-reported willingness to pay. We hypothesize that this null result is due to the recent emergence of low-cost, low-quality compact fluorescent bulbs in the Saint Lucian lighting market, which may be negatively influencing consumers' preferences and expectations regarding energy-efficient lighting. Findings support the argument that government-sponsored education and subsidy programs will likely result in increased use of energy-saving technologies in Saint Lucia. But such behavioral changes may not be sustained in the long run unless low quality bulbs – the “lemons” of the compact fluorescent lighting market – can be clearly identified by consumers. - Highlights: ▶ We model how knowledge, attitudes, and past purchase affect CFL adoption. ▶ Saint Lucian consumers have some knowledge of and favorable attitudes toward CFLs. ▶ Energy efficiency knowledge increases stated willingness-to-pay (WTP) for CFLs. ▶ Past purchase does not increase WTP; low-quality ‘lemons’ may influence consumers. ▶ Policy can lower consumer risks in lighting markets where low quality bulbs exist.

Energy efficient lighting design for Venlo type greenhouses

NARCIS (Netherlands)

Janssen, E.; Zonneveldt, L.; Sools, F.

2006-01-01

TNO has developed a Radiance software model to calculate the light distribution in the greenhouse using raytracing methods, suitable for daylight and artificial lighting. The model is based on a 3D CAD (Computer aided design) model. The objective is to maximize the efficiency of the artificial

Slow-light-enhanced energy efficiency for graphene microheaters on silicon photonic crystal waveguides

Science.gov (United States)

Yan, Siqi; Zhu, Xiaolong; Frandsen, Lars Hagedorn; Xiao, Sanshui; Mortensen, N. Asger; Dong, Jianji; Ding, Yunhong

2017-01-01

Slow light has been widely utilized to obtain enhanced nonlinearities, enhanced spontaneous emissions and increased phase shifts owing to its ability to promote light–matter interactions. By incorporating a graphene on a slow-light silicon photonic crystal waveguide, here we experimentally demonstrate an energy-efficient graphene microheater with a tuning efficiency of 1.07 nmmW−1 and power consumption per free spectral range of 3.99 mW. The rise and decay times (10–90%) are only 750 and 525 ns, which, to the best of our knowledge, are the fastest reported response times for microheaters in silicon photonics. The corresponding figure of merit of the device is 2.543 nW s, one order of magnitude better than results reported in previous studies. The influence of the length and shape of the graphene heater to the tuning efficiency is further investigated, providing valuable guidelines for enhancing the tuning efficiency of the graphene microheater. PMID:28181531

Membrane systems for energy efficient separation of light gases

Energy Technology Data Exchange (ETDEWEB)

Devlin, D.J.; Archuleta, T.; Barbero, R. [Los Alamos National Lab., NM (United States)] [and others

1997-04-01

Ethylene and propylene are two of the largest commodity chemicals in the United States and are major building blocks for the petrochemicals industry. These olefins are separated currently by cryogenic distillation which demands extremely low temperatures and high pressures. Over 75 billion pounds of ethylene and propylene are distilled annually in the US at an estimated energy requirement of 400 trillion BTU`s. Non-domestic olefin producers are rapidly constructing state-of-the-art plants. These energy-efficient plants are competing with an aging United States olefins industry in which 75% of the olefins producers are practicing technology that is over twenty years old. New separation opportunities are therefore needed to continually reduce energy consumption and remain competitive. Amoco has been a leader in incorporating new separation technology into its olefins facilities and has been aggressively pursuing non-cryogenic alternatives to light gas separations. The largest area for energy reduction is the cryogenic isolation of the product hydrocarbons from the reaction by-products, methane and hydrogen. This separation requires temperatures as low as {minus}150{degrees}F and pressures exceeding 450 psig. This CRADA will focus on developing a capillary condensation process to separate olefinic mixtures from light gas byproducts at temperatures that approach ambient conditions and at pressures less than 250 psig; this technology breakthrough will result in substantial energy savings. The key technical hurdle in the development of this novel separation concept is the precise control of the pore structure of membrane materials. These materials must contain specially-shaped channels in the 20-40A range to provide the driving force necessary to remove the condensed hydrocarbon products. In this project, Amoco is the technology end-user and provides the commercialization opportunity and engineering support.

The efficiency challenge of nitride light-emitting diodes for lighting

KAUST Repository

Weisbuch, Claude

2015-03-13

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. We discuss the challenges of light-emitting diodes in view of their application to solid-state lighting. The requirement is to at least displace the quite efficient fluorescent, sodium, and high intensity discharge lamps used today in the main energy consuming lighting sectors, industrial, commercial and outdoors, with more efficient and better light quality lamps. We show that both from the point of view of cost of ownership and carbon emissions reduction, the relevant metric is efficiency, more than the cost of lumens. Then, progress from present performance requires identification of the loss mechanisms in light emission from LEDs, and solutions competing with mainstream c-plane LEDS grown on sapphire need to be on par with these. Special attention is devoted to a discussion of the efficiency droop mechanisms, and of a recent direct measurement of Auger generated electrons which appear to be responsible for droop.

Human-centered sensor-based Bayesian control: Increased energy efficiency and user satisfaction in commercial lighting

Science.gov (United States)

Granderson, Jessica Ann

2007-12-01

The need for sustainable, efficient energy systems is the motivation that drove this research, which targeted the design of an intelligent commercial lighting system. Lighting in commercial buildings consumes approximately 13% of all the electricity generated in the US. Advanced lighting controls1 intended for use in commercial office spaces have proven to save up to 45% in electricity consumption. However, they currently comprise only a fraction of the market share, resulting in a missed opportunity to conserve energy. The research goals driving this dissertation relate directly to barriers hindering widespread adoption---increase user satisfaction, and provide increased energy savings through more sophisticated control. To satisfy these goals an influence diagram was developed to perform daylighting actuation. This algorithm was designed to balance the potentially conflicting lighting preferences of building occupants, with the efficiency desires of building facilities management. A supervisory control policy was designed to implement load shedding under a demand response tariff. Such tariffs offer incentives for customers to reduce their consumption during periods of peak demand, trough price reductions. In developing the value function occupant user testing was conducted to determine that computer and paper tasks require different illuminance levels, and that user preferences are sufficiently consistent to attain statistical significance. Approximately ten facilities managers were also interviewed and surveyed to isolate their lighting preferences with respect to measures of lighting quality and energy savings. Results from both simulation and physical implementation and user testing indicate that the intelligent controller can increase occupant satisfaction, efficiency, cost savings, and management satisfaction, with respect to existing commercial daylighting systems. Several important contributions were realized by satisfying the research goals. A general

Plasmonics for solid-state lighting : enhanced excitation and directional emission of highly efficient light sources

NARCIS (Netherlands)

Lozano, G.; Louwers, Davy J.; Rodriguez, S.R.K.; Murai, S.; Jansen, O.T.A.; Verschuuren, M.A.; Gomez Rivas, J.

2013-01-01

Light sources based on reliable and energy-efficient light-emitting diodes (LEDs) are instrumental in the development of solid-state lighting (SSL). Most research efforts in SSL have focused on improving both the intrinsic quantum efficiency (QE) and the stability of light emitters. For this reason,

Motion estimation by integrated low cost system (vision and MEMS) for positioning of a scooter "Vespa"

Science.gov (United States)

Guarnieri, A.; Milan, N.; Pirotti, F.; Vettore, A.

2011-12-01

In the automotive sector, especially in these last decade, a growing number of investigations have taken into account electronic systems to check and correct the behavior of drivers, increasing road safety. The possibility to identify with high accuracy the vehicle position in a mapping reference frame for driving directions and best-route analysis is also another topic which attracts lot of interest from the research and development sector. To reach the objective of accurate vehicle positioning and integrate response events, it is necessary to estimate time by time the position, orientation and velocity of the system. To this aim low cost GPS and MEMS (sensors can be used. In comparison to a four wheel vehicle, the dynamics of a two wheel vehicle (e.g. a scooter) feature a higher level of complexity. Indeed more degrees of freedom must be taken into account to describe the motion of the latter. For example a scooter can twist sideways, thus generating a roll angle. A slight pitch angle has to be considered as well, since wheel suspensions have a higher degree of motion with respect to four wheel vehicles. In this paper we present a method for the accurate reconstruction of the trajectory of a motorcycle ("Vespa" scooter), which can be used as alternative to the "classical" approach based on the integration of GPS and INS sensors. Position and orientation of the scooter are derived from MEMS data and images acquired by on-board digital camera. A Bayesian filter provides the means for integrating the data from MEMS-based orientation sensor and the GPS receiver.

Energy Efficient Task Light

DEFF Research Database (Denmark)

Logadottir, Asta; Ardkapan, Siamak Rahimi; Johnsen, Kjeld

2014-01-01

The objectives of this work is to develop a task light for office lighting that fulfils the minimum requirements of the European standard EN12464 - 1 : Light and lighting – Lighting of work places, Part 1: Indoor workplaces and the Danish standard DS 700 : Lys og belysning I arbejdsrum , or more...... specifically the requirements that apply to the work area and the immediate surrounding area. By providing a task light that fulfils the requirements for task lighting and the immediate surrounding area, the general lighting only needs to provide the illuminance levels required for background lighting...... and thereby a reduction in installed power for general lighting of about 40 % compared to the way illuminance levels are designed in an office environment in Denmark today. This lighting strategy is useful when the placement of the task area is not defined in the space before the lighting is design ed...

Transport Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Transport is the sector with the highest final energy consumption and, without any significant policy changes, is forecast to remain so. In 2008, the IEA published 25 energy efficiency recommendations, among which four are for the transport sector. The recommendations focus on road transport and include policies on improving tyre energy efficiency, fuel economy standards for both light-duty vehicles and heavy-duty vehicles, and eco-driving. Implementation of the recommendations has been weaker in the transport sector than others. This paper updates the progress that has been made in implementing the transport energy efficiency recommendations in IEA countries since March 2009. Many countries have in the last year moved from 'planning to implement' to 'implementation underway', but none have fully implemented all transport energy efficiency recommendations. The IEA calls therefore for full and immediate implementation of the recommendations.

Highly efficient greenish-blue platinum-based phosphorescent organic light-emitting diodes on a high triplet energy platform

Energy Technology Data Exchange (ETDEWEB)

Chang, Y. L., E-mail: yilu.chang@mail.utoronto.ca; Gong, S., E-mail: sgong@chem.utoronto.ca; White, R.; Lu, Z. H., E-mail: zhenghong.lu@utoronto.ca [Department of Materials Science and Engineering, University of Toronto, 184 College St., Toronto, Ontario M5S 3E4 (Canada); Wang, X.; Wang, S., E-mail: wangs@chem.queensu.ca [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario K7L 3N6 (Canada); Yang, C. [Department of Chemistry, Wuhan University, Wuhan 430072 (China)

2014-04-28

We have demonstrated high-efficiency greenish-blue phosphorescent organic light-emitting diodes (PHOLEDs) based on a dimesitylboryl-functionalized C^N chelate Pt(II) phosphor, Pt(m-Bptrz)(t-Bu-pytrz-Me). Using a high triplet energy platform and optimized double emissive zone device architecture results in greenish-blue PHOLEDs that exhibit an external quantum efficiency of 24.0% and a power efficiency of 55.8 lm/W. This record high performance is comparable with that of the state-of-the-art Ir-based sky-blue organic light-emitting diodes.

Light extraction efficiency enhancement for fluorescent SiC based white light-emitting diodes

DEFF Research Database (Denmark)

Ou, Haiyan; Ou, Yiyu; Argyraki, Aikaterini

Fluorescent SiC based white light-emitting diodes(LEDs) light source, as an innovative energy-efficient light source, would even have longer lifetime, better light quality and eliminated blue-tone effect, compared to the current phosphor based white LED light source. In this paper, the yellow...

All-terrain vehicle, trampoline and scooter injuries and their prevention in children.

Science.gov (United States)

Levine, Deborah

2006-06-01

Childhood injuries are the leading cause of death in children and result in significant healthcare utilization. Injuries specifically related to all terrain vehicles, trampolines and scooter usage can be devastating and are often preventable. Our understanding of how and why these injuries occur can aid in preventing morbidity and mortality. The popularity of all-terrain vehicles, nonmotorized scooters and trampolines has soared over recent years. This increased usage has led to a tremendous rise in injuries in children utilizing these recreational activities. Many of the injuries occur in younger children who may not possess the motor and cognitive skills necessary to safely engage in these activities. These activities lead to a number of head and extremity injuries, most of which can be attenuated by the use of protective gear such as helmets and protective padding. Understanding the nature of these injuries can lead to advocacy and hopefully legislation to prevent further injuries from occurring.

Highly efficient silicon light emitting diode

NARCIS (Netherlands)

Le Minh, P.; Holleman, J.; Wallinga, Hans

2002-01-01

In this paper, we describe the fabrication, using standard silicon processing techniques, of silicon light-emitting diodes (LED) that efficiently emit photons with energy around the silicon bandgap. The improved efficiency had been explained by the spatial confinement of charge carriers due to a

Improvement of energy efficiency and quality of street lighting in South Italy as an action of Sustainable Energy Action Plans. The case study of Comiso (RG)

International Nuclear Information System (INIS)

Beccali, Marco; Bonomolo, Marina; Ciulla, Giuseppina; Galatioto, Alessandra; Lo Brano, Valerio

2015-01-01

Existing street lighting systems, in most of South Italy cities, are often inefficient due to the obsolescence of lamps and luminaires and of ineffective light control systems unable to implement efficient on-off and dimming strategies. Energy efficiency improvement, in street lighting systems, is often one of the key actions to be adopted by Public Administration in their Sustainable Energy Action Plan in the framework of the “Covenant of Majors” activities. As a task of FACTOR 20 project, a set of planning options has been analysed and proposed. Particularly, street lighting efficiency projects have been studied for representative case studies. A detailed survey of the public lighting systems, in Comiso, allowed represent current performance figures such us installed power, luminance and illuminance levels in roads categories, electricity consumption, switching and dimming schedules. A project of system upgrade has been elaborated. To do this, many lighting simulations, energy and economic assessments in three scenarios have been performed. The obtained results show that high improvements of the lighting quality are foreseeable together with large energy and economic saving. An economic sensitivity analysis, has shown how the performance can change. The proposed methodology can be applied in many similar South Italy cities. - Highlights: • Retrofit actions in urban lighting systems of typical South Italy cities are studied. • A methodology for the comparison of baseline and design scenarios is presented. • An analysis of energy and economic savings of different scenarios is performed. • A sensitivity analysis of payback times is presented for different costs of LED and kWhe.

Impact assessment of energy-efficient lighting in patients with lupus erythematosus: a pilot study.

Science.gov (United States)

Fenton, L; Dawe, R; Ibbotson, S; Ferguson, J; Silburn, S; Moseley, H

2014-03-01

Patients with lupus erythematosus (LE) are often abnormally photosensitive. Ultraviolet (UV) exposure can not only induce cutaneous lesions but may also contribute to systemic flares and disease progression. Various forms of energy-efficient lighting have been shown to emit UV radiation. To determine the effects of these emissions on individuals with LE. This assessment investigated cutaneous responses to repeated exposures from three types of lighting: compact fluorescent lamp (CFL), light-emitting diode (LED) and energy-efficient halogen (EEH). The subjects were 15 patients with LE and a control group of five healthy volunteers. No cutaneous LE lesions were induced by any of the light sources. Delayed skin erythema was induced at the site of CFL irradiation in six of the 15 patients with LE and two of the five healthy subjects. Erythema was increased in severity and more persistent in patients with LE. One patient with LE produced a positive delayed erythema to the EEH. A single patient with LE produced immediate abnormal erythemal responses to the CFL, LED and EEH. Further investigation revealed that this patient also had solar urticaria. All other subjects had negative responses to LED exposure. Compact fluorescent lamps emit UV that can induce skin erythema in both individuals with LE and healthy individuals when situated in close proximity. However, this occurs to a greater extent and is more persistent in patients with LE. EEHs emit UVA that can induce erythema in patients with LE. LEDs provide a safer alternative light source without risk of UV exposure. © 2013 British Association of Dermatologists.

Energy-efficiency labels and standards: A guidebook for appliances, equipment and lighting

Energy Technology Data Exchange (ETDEWEB)

McMahon, James E.; Wiel, Stephen

2001-02-16

Energy-performance improvements in consumer products are an essential element in any government's portfolio of energy-efficiency and climate change mitigation programs. Governments need to develop balanced programs, both voluntary and regulatory, that remove cost-ineffective, energy-wasting products from the marketplace and stimulate the development of cost-effective, energy-efficient technology. Energy-efficiency labels and standards for appliances, equipment, and lighting products deserve to be among the first policy tools considered by a country's energy policy makers. The U.S. Agency for International Development (USAID) and the United Nations Foundation (UNF) recognize the need to support policy makers in their efforts to implement energy-efficiency standards and labeling programs and have developed this guidebook, together with the Collaborative Labeling and Appliance Standards Program (CLASP), as a primary reference. This guidebook was prepared over the course of the past year with significant contribution from the authors and reviewers mentioned previously. Their diligent participation has made this the international guidance tool it was intended to be. The lead authors would also like to thank the following individuals for their support in the development, production, and distribution of the guidebook: Marcy Beck, Elisa Derby, Diana Dhunke, Ted Gartner, and Julie Osborn of Lawrence Berkeley National Laboratory as well as Anthony Ma of Bevilacqua-Knight, Inc. This guidebook is designed as a manual for government officials and others around the world responsible for developing, implementing, enforcing, monitoring, and maintaining labeling and standards-setting programs. It discusses the pros and cons of adopting energy-efficiency labels and standards and describes the data, facilities, and institutional and human resources needed for these programs. It provides guidance on the design, development, implementation, maintenance, and evaluation of the

Green corridor : energy efficiency initiatives

Energy Technology Data Exchange (ETDEWEB)

Bartlett, M.; Strickland, R.; Harding, N. [Windsor Univ., ON (Canada)

2005-07-01

This presentation discussed environmental sustainability using alternative energy technologies. It discussed Ecohouse, which is a house designed using conventional and inventive products and techniques to represent an eco-efficient model for living, a more sustainable house, demonstrating sustainable technologies in action and setting a new standard for resource efficiency in Windsor. The presentation provided a building analysis and discussed the following: geothermal heating; distributive power; green roof; net metering; grey water plumbing; solar water heating; passive lighting; energy efficient lighting and geothermal heating and cooling. It also discussed opportunities for innovation, namely: greenhouse; composting toilets; alternative insulation; net metering; solar arrays; hydroponics; and expansion of the house. Also discussed were a nature bridge, an underwater electric kite, and a vertically aerodynamic turbine. The benefits of renewable energy, small hydro power potential, and instream energy generation technology were presented. 9 refs., figs.

Light quality and efficiency of consumer grade solid state lighting products

Science.gov (United States)

Dam-Hansen, Carsten; Corell, Dennis Dan; Thorseth, Anders; Poulsen, Peter Behrensdorff

2013-03-01

The rapid development in flux and efficiency of Light Emitting Diodes (LED) has resulted in a flooding of the lighting market with Solid State Lighting (SSL) products. Many traditional light sources can advantageously be replaced by SSL products. There are, however, large variations in the quality of these products, and some are not better than the ones they are supposed to replace. A lack of quality demands and standards makes it difficult for consumers to get an overview of the SSL products. Here the results of a two year study investigating SSL products on the Danish market are presented. Focus has been on SSL products for replacement of incandescent lamps and halogen spotlights. The warm white light and good color rendering properties of these traditional light sources are a must for lighting in Denmark and the Nordic countries. 266 SSL replacement lamps have been tested for efficiency and light quality with respect to correlated color temperature and color rendering properties. This shows a trade-off between high color rendering warm white light and energy efficiency. The lumen and color maintenance over time has been investigated and results for products running over 11000 h will be presented. A new internet based SSL product selection tool will be shown. Here the products can be compared on efficiency, light quality parameters, thus providing a better basis for the selection of SSL products for consumers.

An economic perspective on the reliability of lighting systems in building with highly efficient energy: A case study

International Nuclear Information System (INIS)

Salata, F.; Lieto Vollaro, A. de; Ferraro, A.

2014-01-01

Highlights: • Proper design of efficient lighting systems. • The reliability and durability of the light sources. • Maintenance of lighting systems. • Quality standards of LED lamps. • Optimum economic choice of light sources. - Abstract: The performance of lighting system must be calculated in order to determine the energy requirements of the building. In the normative [EN 12464-1] are established lighting requirements which have effects on energy needs. The European standard [EN 15193] provides guidance on that evaluation. The easiest way to comply with reduction of energy requirements leads to the replacement of traditional lamps with LED ones, but if we calculate also the reliability parameters, the economic return is not guaranteed. Using bibliographic data, we have compared lighting’s results for a museum (LED lamps versus CFL and halogen lamps). The objective function of the study is to optimize the energy consumption of lighting systems, but at the same time to assess the reliability (MTTF of the lamps) of these systems. Without accurate information about this last parameters, the right choice of the lamps cannot be done successfully

How to harvest efficient laser from solar light

Science.gov (United States)

Zhao, Changming; Guan, Zhe; Zhang, Haiyang

2018-02-01

Solar Pumped Solid State Lasers (SPSSL) is a kind of solid state lasers that can transform solar light into laser directly, with the advantages of least energy transform procedure, higher energy transform efficiency, simpler structure, higher reliability, and longer lifetime, which is suitable for use in unmanned space system, for solar light is the only form of energy source in space. In order to increase the output power and improve the efficiency of SPSSL, we conducted intensive studies on the suitable laser material selection for solar pump, high efficiency/large aperture focusing optical system, the optimization of concave cavity as the second focusing system, laser material bonding and surface processing. Using bonded and grooved Nd:YAG rod as laser material, large aperture Fresnel lens as the first stage focusing element, concave cavity as the second stage focusing element, we finally got 32.1W/m2 collection efficiency, which is the highest collection efficiency in the world up to now.

Factors which influence Nova Scotia farmers in implementing energy efficiency and renewable energy measures

International Nuclear Information System (INIS)

Bailey, J.A.; Gordon, R.; Burton, D.; Yiridoe, E.K.

2008-01-01

Improvements in energy efficiency and renewable energy use can reduce farm operating costs and reduce greenhouse gas (GHG) emissions. Responses (n=224, representing a 32% response rate) from a mail survey were used to assess use and interest in energy efficient and renewable energy options on farms in Nova Scotia, Canada. Energy efficiency options used the most were behavior, insulation, and lighting. Few farms used renewable energy options. Approximately 78% of farmers indicated an interest in implementing energy efficiency and renewable energy options. Interest varied by farm type and size. Interest increased with farm size. The two main efficiency options of interest were lighting (60.8%) and insulation (43.7%), while wind power development (55.5%) and solar water heating (24.5%) were the main renewable options of interest. Farmers concerned about power and equipment reliability were less likely to be interested in implementing options. Farmers concerned about the environment were more likely to be interested in implementing options. Current use of certain energy efficiency technologies, such as efficient lighting, influenced implementation interest

Strategies to enhance the excitation energy-transfer efficiency in a light-harvesting system using the intra-molecular charge transfer character of carotenoids

Energy Technology Data Exchange (ETDEWEB)

Yukihira, Nao [Department of Applied Chemistry for Environment; School of Science and Technology; Kwansei Gakuin University; Sanda; Japan; Sugai, Yuko [Department of Applied Chemistry for Environment; School of Science and Technology; Kwansei Gakuin University; Sanda; Japan; Fujiwara, Masazumi [Department of Applied Chemistry for Environment; School of Science and Technology; Kwansei Gakuin University; Sanda; Japan; Kosumi, Daisuke [Institute of Pulsed Power Science; Kumamoto University; Kumamoto; Japan; Iha, Masahiko [South Product Co. Ltd.; Uruma-shi; Japan; Sakaguchi, Kazuhiko [Department of Chemistry; Graduate School of Science; Osaka City University; Osaka 558-8585; Japan; Katsumura, Shigeo [Department of Chemistry; Graduate School of Science; Osaka City University; Osaka 558-8585; Japan; Gardiner, Alastair T. [Glasgow Biomedical Research Centre; University of Glasgow; 126 University Place; Glasgow, G12 8QQ; UK; Cogdell, Richard J. [Glasgow Biomedical Research Centre; University of Glasgow; 126 University Place; Glasgow, G12 8QQ; UK; Hashimoto, Hideki [Department of Applied Chemistry for Environment; School of Science and Technology; Kwansei Gakuin University; Sanda; Japan

2017-01-01

Fucoxanthin is a carotenoid that is mainly found in light-harvesting complexes from brown algae and diatoms. Due to the presence of a carbonyl group attached to polyene chains in polar environments, excitation produces an excited intra-molecular charge transfer. This intra-molecular charge transfer state plays a key role in the highly efficient (~95%) energy-transfer from fucoxanthin to chlorophyllain the light-harvesting complexes from brown algae. In purple bacterial light-harvesting systems the efficiency of excitation energy-transfer from carotenoids to bacteriochlorophylls depends on the extent of conjugation of the carotenoids. In this study we were successful, for the first time, in incorporating fucoxanthin into a light-harvesting complex 1 from the purple photosynthetic bacterium,Rhodospirillum rubrumG9+ (a carotenoidless strain). Femtosecond pump-probe spectroscopy was applied to this reconstituted light-harvesting complex in order to determine the efficiency of excitation energy-transfer from fucoxanthin to bacteriochlorophyllawhen they are bound to the light-harvesting 1 apo-proteins.

Three-Dimensional Hetero-Integration of Faceted GaN on Si Pillars for Efficient Light Energy Conversion Devices.

Science.gov (United States)

Kim, Dong Rip; Lee, Chi Hwan; Cho, In Sun; Jang, Hanmin; Jeon, Min Soo; Zheng, Xiaolin

2017-07-25

An important pathway for cost-effective light energy conversion devices, such as solar cells and light emitting diodes, is to integrate III-V (e.g., GaN) materials on Si substrates. Such integration first necessitates growth of high crystalline III-V materials on Si, which has been the focus of many studies. However, the integration also requires that the final III-V/Si structure has a high light energy conversion efficiency. To accomplish these twin goals, we use single-crystalline microsized Si pillars as a seed layer to first grow faceted Si structures, which are then used for the heteroepitaxial growth of faceted GaN films. These faceted GaN films on Si have high crystallinity, and their threading dislocation density is similar to that of GaN grown on sapphire. In addition, the final faceted GaN/Si structure has great light absorption and extraction characteristics, leading to improved performance for GaN-on-Si light energy conversion devices.

Efficient light-harvesting using non-carbonyl carotenoids: Energy transfer dynamics in the VCP complex from Nannochloropsis oceanica.

Science.gov (United States)

Keşan, Gürkan; Litvín, Radek; Bína, David; Durchan, Milan; Šlouf, Václav; Polívka, Tomáš

2016-04-01

Violaxanthin-chlorophyll a protein (VCP) from Nannochloropsis oceanica is a Chl a-only member of the LHC family of light-harvesting proteins. VCP binds carotenoids violaxanthin (Vio), vaucheriaxanthin (Vau), and vaucheriaxanthin-ester (Vau-ester). Here we report on energy transfer pathways in the VCP complex. The overall carotenoid-to-Chla energy transfer has efficiency over 90%. Based on their energy transfer properties, the carotenoids in VCP can be divided into two groups; blue carotenoids with the lowest energy absorption band around 480nm and red carotenoids with absorption extended up to 530nm. Both carotenoid groups transfer energy efficiently from their S2 states, reaching efficiencies of ~70% (blue) and ~60% (red). The S1 pathway, however, is efficient only for the red carotenoid pool for which two S1 routes characterized by 0.33 and 2.4ps time constants were identified. For the blue carotenoids the S1-mediated pathway is represented only by a minor route likely involving a hot S1 state. The relaxed S1 state of blue carotenoids decays to the ground state within 21ps. Presence of a fraction of non-transferring red carotenoids with the S1 lifetime of 13ps indicates some specific carotenoid-protein interaction that must shorten the intrinsic S1 lifetime of Vio and/or Vau whose S1 lifetimes in methanol are 26 and 29ps, respectively. The VCP complex from N. oceanica is the first example of a light-harvesting complex binding only non-carbonyl carotenoids with carotenoid-to-chlorophyll energy transfer efficiency over 90%. Copyright © 2015 Elsevier B.V. All rights reserved.

Energy resolution and efficiency of phonon-mediated kinetic inductance detectors for light detection

International Nuclear Information System (INIS)

Cardani, L.; Colantoni, I.; Coppolecchia, A.; Cruciani, A.; Vignati, M.; Bellini, F.; Casali, N.; Cosmelli, C.; Di Domizio, S.; Castellano, M. G.; Tomei, C.

2015-01-01

The development of sensitive cryogenic light detectors is of primary interest for bolometric experiments searching for rare events like dark matter interactions or neutrino-less double beta decay. Thanks to their good energy resolution and the natural multiplexed read-out, Kinetic Inductance Detectors (KIDs) are particularly suitable for this purpose. To efficiently couple KIDs-based light detectors to the large crystals used by the most advanced bolometric detectors, active surfaces of several cm 2 are needed. For this reason, we are developing phonon-mediated detectors. In this paper, we present the results obtained with a prototype consisting of four 40 nm thick aluminum resonators patterned on a 2 × 2 cm 2 silicon chip, and calibrated with optical pulses and X-rays. The detector features a noise resolution σ E  = 154 ± 7 eV and an (18 ± 2)% efficiency

Energy resolution and efficiency of phonon-mediated kinetic inductance detectors for light detection

Energy Technology Data Exchange (ETDEWEB)

Cardani, L., E-mail: laura.cardani@roma1.infn.it [Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy); Physics Department, Princeton University, Washington Road, 08544, Princeton, New Jersey (United States); Colantoni, I.; Coppolecchia, A. [Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy); Cruciani, A.; Vignati, M.; Bellini, F.; Casali, N.; Cosmelli, C. [Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy); INFN - Sezione di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy); Di Domizio, S. [Dipartimento di Fisica, Università degli Studi di Genova, Via Dodecaneso 33, 16146 Genova (Italy); INFN - Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Castellano, M. G. [Istituto di Fotonica e Nanotecnologie - CNR, Via Cineto Romano 42, 00156 Roma (Italy); Tomei, C. [INFN - Sezione di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy)

2015-08-31

The development of sensitive cryogenic light detectors is of primary interest for bolometric experiments searching for rare events like dark matter interactions or neutrino-less double beta decay. Thanks to their good energy resolution and the natural multiplexed read-out, Kinetic Inductance Detectors (KIDs) are particularly suitable for this purpose. To efficiently couple KIDs-based light detectors to the large crystals used by the most advanced bolometric detectors, active surfaces of several cm{sup 2} are needed. For this reason, we are developing phonon-mediated detectors. In this paper, we present the results obtained with a prototype consisting of four 40 nm thick aluminum resonators patterned on a 2 × 2 cm{sup 2} silicon chip, and calibrated with optical pulses and X-rays. The detector features a noise resolution σ{sub E} = 154 ± 7 eV and an (18 ± 2)% efficiency.

Opportunities of energy saving in lighting systems for public buildings

Directory of Open Access Journals (Sweden)

Ayman Abd El-khalek

2017-03-01

Full Text Available The lighting system provides many options for cost-effective energy saving with low or no inconvenience. Lighting improvements are excellent investments in most public buildings, it is usually cost-effective to address because lighting improvements are often easier to make than many process upgrades.For public buildings, the easy no and low cost options to help save money and improve the energy performance are:Understand energy use.Identify optionsPrioritize actionsMake the changes and measure the savings.Continue managing energy efficiency.The challenge is to retrofit traditional lamps with LED lamps of good quality. The benefits of LED light bulbs are long-lasting, durable, cool, mercury free, more efficient, and cost effective.The light Emitting Diode (LED bulb uses a semiconductor as its light source, and is currently one of the most energy efficient and quickly developing types of bulbs for lighting. LEDs increasingly are being purchased to replace traditional bulbs. LEDs are relatively more expensive than other types of bulbs, but are very cost-effective because they use only a fraction of electricity of traditional lighting methods nd can last for longer.Benchmarking guides decision makers to policies aimed at the energy sector through better understanding of energy consumption trends nationwide, e.g.: energy price, moderating, peak demand, and encouraging sectors, low energy expansions.The “Improving Energy Efficiency Project of Lighting and Appliances” carried out energy audits and implemented opportunities of energy saving in lighting for different type of public buildings.To rationalize the use of energy by giving guidelines to consumers, the IEEL&A project prepared some brochures.This paper leads with the results of case studies as energy audits, opportunities in lighting systems, energy saving and CO2 reduction.

The role of energy losses in photosynthetic light harvesting

Science.gov (United States)

Krüger, T. P. J.; van Grondelle, R.

2017-07-01

Photosynthesis operates at the bottom of the food chain to convert the energy of light into carbohydrates at a remarkable global rate of about 130 TW. Nonetheless, the overall photosynthetic process has a conversion efficiency of a few percent at best, significantly less than bottom-up photovoltaic cells. The primary photosynthetic steps, consisting of light harvesting and charge separation, are often presented as having near-unity quantum efficiency but this holds only true under ideal conditions. In this review, we discuss the importance of energy loss mechanisms to establish robustness in photosynthetic light harvesting. Thermal energy dissipation of light-harvesting complexes (LHCs) in different environments is investigated and the relationships and contrasts between concentration quenching of high pigment concentrations, photoprotection (non-photochemical quenching), quenching due to protein aggregation, and fluorescence blinking are discussed. The role of charge-transfer states in light harvesting and energy dissipation is highlighted and the importance of controlled protein structural disorder to switch the light-harvesting antennae between effective light harvesters and efficient energy quenchers is underscored. The main LHC of plants, LHCII, is used as a prime example.

Metasurface integrated high energy efficient and high linearly polarized InGaN/GaN light emitting diode.

Science.gov (United States)

Wang, Miao; Xu, Fuyang; Lin, Yu; Cao, Bing; Chen, Linghua; Wang, Chinhua; Wang, Jianfeng; Xu, Ke

2017-07-06

We proposed and demonstrated an integrated high energy efficient and high linearly polarized InGaN/GaN green LED grown on (0001) oriented sapphire with combined metasurface polarizing converter and polarizer system. It is different from those conventional polarized light emissions generated with plasmonic metallic grating in which at least 50% high energy loss occurs inherently due to high reflection of the transverse electric (TE) component of an electric field. A reflecting metasurface, with a two dimensional elliptic metal cylinder array (EMCA) that functions as a half-wave plate, was integrated at the bottom of a LED such that the back-reflected TE component, that is otherwise lost by a dielectric/metal bi-layered wire grids (DMBiWG) polarizer on the top emitting surface of the LED, can be converted to desired transverse magnetic (TM) polarized emission after reflecting from the metasurface. This significantly enhances the polarized light emission efficiency. Experimental results show that extraction efficiency of the polarized emission can be increased by 40% on average in a wide angle of ±60° compared to that with the naked bottom of sapphire substrate, or 20% compared to reflecting Al film on the bottom of a sapphire substrate. An extinction ratio (ER) of average value 20 dB within an angle of ±60° can be simultaneously obtained directly from an InGaN/GaN LED. Our results show the possibility of simultaneously achieving a high degree of polarization and high polarization extraction efficiency at the integrated device level. This advances the field of GaN LED toward energy efficiency, multi-functional applications in illumination, display, medicine, and light manipulation.

Efficient light emission from inorganic and organic semiconductor hybrid structures by energy-level tuning.

Science.gov (United States)

Schlesinger, R; Bianchi, F; Blumstengel, S; Christodoulou, C; Ovsyannikov, R; Kobin, B; Moudgil, K; Barlow, S; Hecht, S; Marder, S R; Henneberger, F; Koch, N

2015-04-15

The fundamental limits of inorganic semiconductors for light emitting applications, such as holographic displays, biomedical imaging and ultrafast data processing and communication, might be overcome by hybridization with their organic counterparts, which feature enhanced frequency response and colour range. Innovative hybrid inorganic/organic structures exploit efficient electrical injection and high excitation density of inorganic semiconductors and subsequent energy transfer to the organic semiconductor, provided that the radiative emission yield is high. An inherent obstacle to that end is the unfavourable energy level offset at hybrid inorganic/organic structures, which rather facilitates charge transfer that quenches light emission. Here, we introduce a technologically relevant method to optimize the hybrid structure's energy levels, here comprising ZnO and a tailored ladder-type oligophenylene. The ZnO work function is substantially lowered with an organometallic donor monolayer, aligning the frontier levels of the inorganic and organic semiconductors. This increases the hybrid structure's radiative emission yield sevenfold, validating the relevance of our approach.

Efficient light emission from inorganic and organic semiconductor hybrid structures by energy-level tuning

Science.gov (United States)

Schlesinger, R.; Bianchi, F.; Blumstengel, S.; Christodoulou, C.; Ovsyannikov, R.; Kobin, B.; Moudgil, K.; Barlow, S.; Hecht, S.; Marder, S.R.; Henneberger, F.; Koch, N.

2015-01-01

The fundamental limits of inorganic semiconductors for light emitting applications, such as holographic displays, biomedical imaging and ultrafast data processing and communication, might be overcome by hybridization with their organic counterparts, which feature enhanced frequency response and colour range. Innovative hybrid inorganic/organic structures exploit efficient electrical injection and high excitation density of inorganic semiconductors and subsequent energy transfer to the organic semiconductor, provided that the radiative emission yield is high. An inherent obstacle to that end is the unfavourable energy level offset at hybrid inorganic/organic structures, which rather facilitates charge transfer that quenches light emission. Here, we introduce a technologically relevant method to optimize the hybrid structure's energy levels, here comprising ZnO and a tailored ladder-type oligophenylene. The ZnO work function is substantially lowered with an organometallic donor monolayer, aligning the frontier levels of the inorganic and organic semiconductors. This increases the hybrid structure's radiative emission yield sevenfold, validating the relevance of our approach. PMID:25872919

Research on natural lighting in reading spaces of university libraries in Jinan under the perspective of energy-efficiency

Science.gov (United States)

Yang, Zengzhang

2017-11-01

The natural lighting design in the reading spaces of university libraries not only influences physical and mental health of readers but also concerns the energy consumption of the libraries. The scientific and rational design of natural lighting is the key to the design of energy saving for physical environment of the reading space. The paper elaborates the present situation and existed problems of natural lighting in reading spaces of university libraries across Jinan region based on characteristics of light climate of Jinan region and concrete utilization of reading spaces in university libraries, and combining field measurement, survey, research and data analysis of reading spaces in Shandong Women’s University’s library. The paper, under the perspective of energy-efficiency, puts forward proposals to improve natural lighting in the reading spaces of university libraries from five aspects, such as adjustment of interior layout, optimization of outer windows design, employment of the reflector panel, design lighting windows on inner walls and utilization of adjustable sun shading facilities.

Tailoring the Energy Landscape in Quasi-2D Halide Perovskites Enables Efficient Green-Light Emission

KAUST Repository

Quan, Li Na; Zhao, Yongbiao; Garcí a de Arquer, F. Pelayo; Sabatini, Randy; Walters, Grant; Voznyy, Oleksandr; Comin, Riccardo; Li, Yiying; Fan, James Z.; Tan, Hairen; Pan, Jun; Yuan, Mingjian; Bakr, Osman; Lu, Zhenghong; Kim, Dong Ha; Sargent, Edward H.

2017-01-01

Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, their low photoluminescence quantum efficiencies, especially in low-excitation regimes, limit their efficiency for light emission. Consequently, perovskite light-emitting devices are operated under high injection, a regime under which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into a small subpopulation of radiative domains, one can achieve a high quantum yield, even at low excitation intensities. We tailor the composition of quasi-2D perovskites to direct the energy transfer into the lowest-bandgap minority phase and to do so faster than it is lost to nonradiative centers. The new material exhibits 60% photoluminescence quantum yield at excitation intensities as low as 1.8 mW/cm2, yielding a ratio of quantum yield to excitation intensity of 0.3 cm2/mW; this represents a decrease of 2 orders of magnitude in the excitation power required to reach high efficiency compared with the best prior reports. Using this strategy, we report light-emitting diodes with external quantum efficiencies of 7.4% and a high luminescence of 8400 cd/m2.

Tailoring the Energy Landscape in Quasi-2D Halide Perovskites Enables Efficient Green-Light Emission

KAUST Repository

Quan, Li Na

2017-05-10

Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, their low photoluminescence quantum efficiencies, especially in low-excitation regimes, limit their efficiency for light emission. Consequently, perovskite light-emitting devices are operated under high injection, a regime under which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into a small subpopulation of radiative domains, one can achieve a high quantum yield, even at low excitation intensities. We tailor the composition of quasi-2D perovskites to direct the energy transfer into the lowest-bandgap minority phase and to do so faster than it is lost to nonradiative centers. The new material exhibits 60% photoluminescence quantum yield at excitation intensities as low as 1.8 mW/cm2, yielding a ratio of quantum yield to excitation intensity of 0.3 cm2/mW; this represents a decrease of 2 orders of magnitude in the excitation power required to reach high efficiency compared with the best prior reports. Using this strategy, we report light-emitting diodes with external quantum efficiencies of 7.4% and a high luminescence of 8400 cd/m2.

Exciplex-triplet energy transfer: A new method to achieve extremely efficient organic light-emitting diode with external quantum efficiency over 30% and drive voltage below 3 V

Science.gov (United States)

Seo, Satoshi; Shitagaki, Satoko; Ohsawa, Nobuharu; Inoue, Hideko; Suzuki, Kunihiko; Nowatari, Hiromi; Yamazaki, Shunpei

2014-04-01

A novel approach to enhance the power efficiency of an organic light-emitting diode (OLED) by employing energy transfer from an exciplex to a phosphorescent emitter is reported. It was found that excitation energy of an exciplex formed between an electron-transporting material with a π-deficient quinoxaline moiety and a hole-transporting material with aromatic amine structure can be effectively transferred to a phosphorescent iridium complex in an emission layer of a phosphorescent OLED. Moreover, such an exciplex formation increases quantum efficiency and reduces drive voltage. A highly efficient, low-voltage, and long-life OLED based on this energy transfer is also demonstrated. This OLED device exhibited extremely high external quantum efficiency of 31% even without any attempt to enhance light outcoupling and also achieved a low drive voltage of 2.8 V and a long lifetime of approximately 1,000,000 h at a luminance of 1,000 cd/m2.

The role of energy losses in photosynthetic light harvesting

International Nuclear Information System (INIS)

Krüger, T P J; Van Grondelle, R

2017-01-01

Photosynthesis operates at the bottom of the food chain to convert the energy of light into carbohydrates at a remarkable global rate of about 130 TW. Nonetheless, the overall photosynthetic process has a conversion efficiency of a few percent at best, significantly less than bottom-up photovoltaic cells. The primary photosynthetic steps, consisting of light harvesting and charge separation, are often presented as having near-unity quantum efficiency but this holds only true under ideal conditions. In this review, we discuss the importance of energy loss mechanisms to establish robustness in photosynthetic light harvesting. Thermal energy dissipation of light-harvesting complexes (LHCs) in different environments is investigated and the relationships and contrasts between concentration quenching of high pigment concentrations, photoprotection (non-photochemical quenching), quenching due to protein aggregation, and fluorescence blinking are discussed. The role of charge-transfer states in light harvesting and energy dissipation is highlighted and the importance of controlled protein structural disorder to switch the light-harvesting antennae between effective light harvesters and efficient energy quenchers is underscored. The main LHC of plants, LHCII, is used as a prime example. (topical review)

CH3 NH3 PbBr3 Perovskite Nanocrystals as Efficient Light-Harvesting Antenna for Fluorescence Resonance Energy Transfer.

Science.gov (United States)

Muthu, Chinnadurai; Vijayan, Anuja; Nair, Vijayakumar C

2017-05-04

Hybrid perovskites have created enormous research interest as a low-cost material for high-performance photovoltaic devices, light-emitting diodes, photodetectors, memory devices and sensors. Perovskite materials in nanocrystal form that display intense luminescence due to the quantum confinement effect were found to be particularly suitable for most of these applications. However, the potential use of perovskite nanocrystals as a light-harvesting antenna for possible applications in artificial photosynthesis systems is not yet explored. In the present work, we study the light-harvesting antenna properties of luminescent methylammonium lead bromide (CH 3 NH 3 PbBr 3 )-based perovskite nanocrystals using fluorescent dyes (rhodamine B, rhodamine 101, and nile red) as energy acceptors. Our studies revealed that CH 3 NH 3 PbBr 3 nanocrystals are an excellent light-harvesting antenna, and efficient fluorescence resonance energy transfer occurs from the nanocrystals to fluorescent dyes. Further, the energy transfer efficiency is found to be highly dependent on the number of anchoring groups and binding ability of the dyes to the surface of the nanocrystals. These observations may have significant implications for perovskite-based light-harvesting devices and their possible use in artificial photosynthesis systems. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Energy efficiency. Lever for the German energy transition

International Nuclear Information System (INIS)

Persem, Melanie; Roesner, Sven

2014-05-01

This document provides some key data on energy consumption in housing and public buildings, indicates the national German objectives in terms of reduction of energy consumption, of reduction of electricity consumption, of energy efficiency, and of evolution of energy consumption in housing and public buildings and in the transport sector. It gives some data related to energy saving and achievements: energy efficiency of the German economy, improvements in housing energy efficiency and insulation, financial support for low income households, reduction of energy consumption within small-medium enterprises, the public sector, the data processing sector and public lighting, and energy saving potential by renewal of public buildings. It indicates the main measures and arrangements: information, support programs for enterprises, local communities and individuals. A graph illustrates a comparison of shares of household power consumption in France and in Germany

Innovations in Multi-Level Governance for Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Recent IEA analysis highlights member countries' significant progress with developing energy efficiency policy (International Energy Agency 2009). The 28 member countries of the IEA are engaged in promoting innovative financial instruments, energy efficiency strategies and action plans. They are designing policies to promote energy efficiency in buildings, the adoption of standby power, the phase out of inefficient lighting, proper tyre-inflation and related policies, and energy efficiency in utilities.

Innovations in Multi-Level Governance for Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Recent IEA analysis highlights member countries' significant progress with developing energy efficiency policy (International Energy Agency 2009). The 28 member countries of the IEA are engaged in promoting innovative financial instruments, energy efficiency strategies and action plans. They are designing policies to promote energy efficiency in buildings, the adoption of standby power, the phase out of inefficient lighting, proper tyre-inflation and related policies, and energy efficiency in utilities.

Diffusion of new automotive technologies for improving energy efficiency in Brazil's light vehicle fleet

International Nuclear Information System (INIS)

Bastin, Cristina; Szklo, Alexandre; Rosa, Luiz Pinguelli

2010-01-01

Historically, Brazil has promoted the development and sales of light duty vehicles running on ethanol (firstly, ethanol-dedicated cars, and recently flexfuel cars). In the 1990s, the country also favored the sales of compact cars to middle and low-income classes. However, in the last years, the profile of vehicles sold in Brazil has converged towards larger and less-efficient vehicles. In 2008, Brazil launched the vehicle labeling program. Based on the outcomes of the historical programs oriented towards the development of automotive innovations, and on a survey conducted with the country's main auto makers, this article evaluates whether the vehicle labeling program will both improve the energy efficiency of light vehicles, and introduce new technologies. Our results indicate that, despite its virtuous intentions, the program will not control the tendency of rising fuel consumption of passenger cars sold in Brazil. Therefore, other policies are needed to boost innovations in Brazil's automotive industry. (author)

White organic light-emitting diodes with fluorescent tube efficiency.

Science.gov (United States)

Reineke, Sebastian; Lindner, Frank; Schwartz, Gregor; Seidler, Nico; Walzer, Karsten; Lüssem, Björn; Leo, Karl

2009-05-14

The development of white organic light-emitting diodes (OLEDs) holds great promise for the production of highly efficient large-area light sources. High internal quantum efficiencies for the conversion of electrical energy to light have been realized. Nevertheless, the overall device power efficiencies are still considerably below the 60-70 lumens per watt of fluorescent tubes, which is the current benchmark for novel light sources. Although some reports about highly power-efficient white OLEDs exist, details about structure and the measurement conditions of these structures have not been fully disclosed: the highest power efficiency reported in the scientific literature is 44 lm W(-1) (ref. 7). Here we report an improved OLED structure which reaches fluorescent tube efficiency. By combining a carefully chosen emitter layer with high-refractive-index substrates, and using a periodic outcoupling structure, we achieve a device power efficiency of 90 lm W(-1) at 1,000 candelas per square metre. This efficiency has the potential to be raised to 124 lm W(-1) if the light outcoupling can be further improved. Besides approaching internal quantum efficiency values of one, we have also focused on reducing energetic and ohmic losses that occur during electron-photon conversion. We anticipate that our results will be a starting point for further research, leading to white OLEDs having efficiencies beyond 100 lm W(-1). This could make white-light OLEDs, with their soft area light and high colour-rendering qualities, the light sources of choice for the future.

Experimental Evaluation of Supercapacitor-Fuel Cell Hybrid Power Source for HY-IEL Scooter

Directory of Open Access Journals (Sweden)

Piotr Bujlo

2013-01-01

Full Text Available This paper presents the results of development of a hybrid fuel cell supercapacitor power system for vehicular applications that was developed and investigated at the Energy Sources Research Section of the Wroclaw Division of Electrotechnical Institute (IEL/OW. The hybrid power source consists of a polymer exchange membrane fuel cell (PEMFC stack and an energy-type supercapacitor that supports the system in time of peak power demands. The developed system was installed in the HY-IEL electric scooter. The vehicle was equipped with auxiliary components (e.g., air compressor, hydrogen tank, and electromagnetic valves needed for proper operation of the fuel cell stack, as well as electronic control circuits and a data storage unit that enabled on-line recording of system and vehicle operation parameters. Attention is focused on the system energy flow monitoring. The experimental part includes field test results of a vehicle powered with the fuel cell-supercapacitor system. Values of currents and voltages recorded for the system, as well as the vehicle’s velocity and hydrogen consumption rate, are presented versus time of the experiment. Operation of the hybrid power system is discussed and analysed based on the results of measurements obtained.

Chapter 2: Commercial and Industrial Lighting Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

Energy Technology Data Exchange (ETDEWEB)

Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gowans, Dakers [Left Fork Energy, Harrison, NY (United States); Telarico, Chad [DNV GL, Mahwah, NJ (United States)

2017-11-02

The Commercial and Industrial Lighting Evaluation Protocol (the protocol) describes methods to account for gross energy savings resulting from the programmatic installation of efficient lighting equipment in large populations of commercial, industrial, and other nonresidential facilities. This protocol does not address savings resulting from changes in codes and standards, or from education and training activities. A separate Uniform Methods Project (UMP) protocol, Chapter 3: Commercial and Industrial Lighting Controls Evaluation Protocol, addresses methods for evaluating savings resulting from lighting control measures such as adding time clocks, tuning energy management system commands, and adding occupancy sensors.

Energy efficiency and renewables policies: Promoting efficiency or facilitating monopsony?

International Nuclear Information System (INIS)

Brennan, Timothy J.

2011-01-01

The cliche in the electricity sector, the 'cheapest power plant is the one we don't build,' neglects the benefits of the energy that plant would generate. That economy-wide perspective need not apply in considering benefits to only consumers if not building that plant was the exercise of monopsony power. A regulator maximizing consumer welfare may need to avoid rationing demand at monopsony prices. Subsidizing energy efficiency to reduce electricity demand at the margin can solve that problem, if energy efficiency and electricity use are substitutes. Renewable energy subsidies, percentage use standards, or feed in tariffs may also serve monopsony as well with sufficient inelasticity in fossil fuel electricity supply. We may not observe these effects if the regulator can set price as well as quantity, lacks buyer-side market power, or is legally precluded from denying generators a reasonable return on capital. Nevertheless, the possibility of monopsony remains significant in light of the debate as to whether antitrust enforcement should maximize consumer welfare or total welfare. - Research Highlights: → Subsidizing energy efficiency can promote monopsony, if efficiency and use are substitutes. → Renewable energy subsidies, portfolio standards, or feed-in tariffs may also promote monopsony. → Effects require buyer-side market power and ability to deny generators a reasonable return. → Monopsony is significant in light of whether antitrust should maximize consumer or total welfare.

Induction of Efficient Energy Dissipation in the Isolated Light-harvesting Complex of Photosystem II in the Absence of Protein Aggregation

NARCIS (Netherlands)

Ilioaia, C.; Johnson, M.P.; Horton, P.; Ruban, A.V.

2008-01-01

Under excess illumination, the Photosystem II light-harvesting antenna of higher plants has the ability to switch into an efficient photoprotective mode, allowing safe dissipation of excitation energy into heat. In this study, we show induction of the energy dissipation state, monitored by

Principles of light energy management

Energy Technology Data Exchange (ETDEWEB)

Davis, N. [Growth Chambers, Chagrin Falls, OH (United States)

1994-12-31

A review is presented on methods to minimize the effects of excess energy associated with lighting systems for plant growth. Information on lamp efficiencies and methods for separating and collecting unwanted heat is included.

UV emissions from low energy artificial light sources.

Science.gov (United States)

Fenton, Leona; Moseley, Harry

2014-01-01

Energy efficient light sources have been introduced across Europe and many other countries world wide. The most common of these is the Compact Fluorescent Lamp (CFL), which has been shown to emit ultraviolet (UV) radiation. Light Emitting Diodes (LEDs) are an alternative technology that has minimal UV emissions. This brief review summarises the different energy efficient light sources available on the market and compares the UV levels and the subsequent effects on the skin of normal individuals and those who suffer from photodermatoses. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Environmentally Benign Technology for Efficient Warm-White Light Emission

Science.gov (United States)

Shen, Pin-Chun; Lin, Ming-Shiun; Lin, Ching-Fuh

2014-06-01

Nowadays efficient down conversion for white light emission is mainly based on rare-earth doped phosphors or cadmium-containing quantum dots. Although they exhibit high luminescence efficiency, the rare-earth mining and cadmium pollution have so far led to extremely high environmental cost, which conflicts the original purpose of pursuing efficient lighting. Here, we explore a new strategy to achieve efficient luminescence conversion based on polymer-decorated nanoparticles. The ZnO and Mn2+ doped ZnS nanoparticles are encapsulated by poly(9,9-di-n- hexylfluorenyl-2,7-diyl). The resultant core-shell nanocomposites then encompass three UV-to-visible luminescence conversion routes for photon emissions at blue, green, and orange colors, respectively. As a result, the color temperature is widely tunable (2100 K ~ 6000 K), so candle light or pure white light can be generated. The quantum yield up to 91% could also be achieved. Such rare-earth-element free nanocomposites give the bright perspectives for energy-saving, healthy, and environmentally benign lighting.

Energy-efficient multicast traffic grooming strategy based on light-tree splitting for elastic optical networks

Science.gov (United States)

Liu, Huanlin; Yin, Yarui; Chen, Yong

2017-07-01

In order to address the problem of optimizing the spectrum resources and power consumption in elastic optical networks (EONs), we investigate the potential gains by jointly employing the light-tree splitting and traffic grooming for multicast requests. An energy-efficient multicast traffic grooming strategy based on light-tree splitting (EED-MTGS-LS) is proposed in this paper. Firstly, we design a traffic pre-processing mechanism to decide the multicast requests' routing order, which considers the request's bandwidth requirement and physical hops synthetically. Then, by dividing a light-tree to some sub-light-trees and grooming the request to these sub-light-trees, the light-tree sharing ratios of multicast requests can be improved. What's more, a priority scheduling vector is constructed, which aims to improve the success rate of spectrum assignment for grooming requests. Finally, a grooming strategy is designed to optimize the total power consumption by reducing the use of transponders and IP routers during routing. Simulation results show that the proposed strategy can significantly improve the spectrum utilization and save the power consumption.

Energy Efficiency Policy Developments: September 2011-September 2012

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

The purpose of this report is to highlight energy efficiency policy action and planning in IEA member and key non-member countries over the period from September 2011 to September 2012. The report provides an overview of energy efficiency policy developments across the seven sectors covered by the IEA 25 Energy Efficiency Policy Recommendations (25 EEPR) – Cross-sectoral activities, Buildings, Appliances and Equipment, Lighting, Transport, Industry and Energy Providers.

Timing growth and development of Campanula by daily light integral and supplemental light level in a cost-efficient light control system

DEFF Research Database (Denmark)

Kjær, Katrine Heinsvig; Ottosen, Carl-Otto; Jørgensen, Bo Nørregaard

2012-01-01

light control system (DynaLight desktop) automatically defines the most cost-efficient use of supplemental light based on predefined setpoints for daily photosynthesis integral (DPI), forecasted solar irradiance and the market price on electricity. It saves energy in high-cost periods of electricity......Two campanula species Campanula portenschlagiana (‘Blue Get Mee’) and Campanula cochlearifolia (‘Blue Wonder’) were grown in a cost-efficient light control system and the effect of supplemental light level and daily light integral (DLI) on growth and development was quantified. The alternative...... the number of flowers and buds and CLI in ‘Blue Get Mee’. The results demonstrate that DLI was the main limiting factor for prediction of growth and development when two campanula species were grown in a cost-efficient light control system where the number of daily light hours was often below the critical...

Using energy efficiently

International Nuclear Information System (INIS)

Nipkow, J.; Brunner, C. U.

2005-01-01

This comprehensive article discusses the perspectives for reducing electricity consumption in Switzerland. The increase in consumption is discussed that has occurred in spite of the efforts of the Swiss national energy programmes 'Energy 2000' and 'SwissEnergy'. The fact that energy consumption is still on the increase although efficient and economically-viable technology is available is commented on. The authors are of the opinion that the market alone cannot provide a complete solution and that national and international efforts are needed to remedy things. In particular, the external costs that are often not included when estimating costs are stressed. Several technical options available, such as the use of fluorescent lighting, LCD monitors and efficient electric motors, are looked at as are other technologies quoted as being a means of reducing power consumption. Ways of reducing stand-by losses and system optimisation are looked at as are various scenarios for further development and measures that can be implemented in order to reduce power consumption

Investing in Energy Efficiency. Removing the Barriers

International Nuclear Information System (INIS)

2004-01-01

Investing in improving energy efficiency has the clear advantages of reducing energy costs, improving security of supply and mitigating the environmental impacts of energy use. And still, many viable opportunities for higher energy efficiency are not tapped because of the existence of numerous barriers to such investments. These lost opportunities imply costs to the individual energy consumers and to the society as a whole and they are particularly important in economies in transition. This report identifies various types of barriers for making energy efficiency investments (be they of legal, administrative, institutional or financial nature), mainly in buildings, district heating and efficient lighting. The role of various bodies and organisations for the facilitation of energy efficiency investments is analysed, from public authorities and regulators to banks and international financing institutions

The production of consuming less: Energy efficiency, climate change, and light bulbs in North Carolina

Science.gov (United States)

Thoyre, Autumn

In this research, I have analyzed the production of consuming less electricity through a case study of promotions of compact fluorescent light bulbs (CFLs). I focused on the CFL because it has been heavily promoted by environmentalists and electricity companies as a key tool for solving climate change, yet such promotions appear counter-intuitive. The magnitude of CFL promotions by environmentalists is surprising because CFLs can only impact less than 1% of U.S. greenhouse gas emissions. CFL promotions by electricity providers are surprising given such companies' normal incentives to sell more of their product. I used political ecological and symbolic interactionist theories, qualitative methods of data collection (including interviews, participant-observation, texts, and images), and a grounded theory analysis to understand this case. My findings suggest that, far from being a self-evident technical entity, energy efficiency is produced as an idea, a part of identities, a resource, and a source of value through social, political, and economic processes. These processes include identity formation and subjectification; gender-coded household labor; and corporate appropriation of household value resulting from environmental governance. I show how environmentalists use CFLs to make and claim neoliberal identities, proposing the concept of green neoliberal identity work as a mechanism through which neoliberal ideologies are translated into practices. I analyze how using this seemingly easy energy efficient technology constitutes labor that is gendered in ways that reflect and reproduce inequalities. I show how electricity companies have used environmental governance to valorize and appropriate home energy efficiency as an accumulation strategy. I conclude by discussing the symbolic power of CFLs, proposing a theory of green obsolescence, and framing the production of energy efficiency as a global production network. I found that promoting energy efficiency involves

Energy conservation through more efficient lighting.

Science.gov (United States)

Maya, J; Grossman, M W; Lagushenko, R; Waymouth, J F

1984-10-26

The efficiency of a mercury-rare gas electrical discharge, which forms the basis of a fluorescent lamp, can be increased about 5 percent simply by increasing the concentration of mercury-196 from 0.146 percent (natural) to about 3 percent. These findings can be implemented immediately without any significant change in the process of manufacturing of this widely used source of illumination, provided that mercury-196 can be obtained economically. The potential energy savings for the United States are estimated to be worth in excess of $200 million per year.

Energy transfer dynamics in Light-Harvesting Dendrimers

Science.gov (United States)

Melinger, Joseph S.; McMorrow, Dale; Kleiman, Valeria D.

2002-03-01

We explore energy transfer dynamics in light-harvesting phenylacetylene symmetric and asymmetric dendrimers. Femtosecond pump-probe spectroscopy is used to probe the ultrafast dynamics of electronic excitations in these dendrimers. The backbone of the macromolecule consists of branches of increasing conjugation length, creating an energy gradient, which funnels energy to an accepting perylene trap. In the case of the symmetric dendrimer (nanostar), the energy transfer efficiency is known to approach nearly unity, although the nature and timescale of the energy transfer process is still unknown. For the asymmetric dendrimers, energy transfer efficiencies are very high, with the possibility of more complex transfer processes. We experimentally monitor the transport of excitons through the light-harvesting dendrimer. The transients show a number of components, with timescales ranging from <300fs to several tens of picoseconds, revealing the complex photophysics taking place in these macromolecules. We interpret our results in terms of the Förster mechanism in which energy transfer occurs through dipole-dipole interactions.

Efficient lighting in buildings: The lack of legislation in Portugal

International Nuclear Information System (INIS)

Almeida, António Manuel; Martins, António Gomes

2014-01-01

The behavior of building designers is conditioned by the existing legislation and regulations in the national context in which they operate. However, in the Portuguese legislation there are no rules concerning the use of daylight, and therefore, designers are not stimulated to adopt solutions that make use of the existing potential of sunlight availability. In the same way, it is difficult to understand the lack of specific regulation, with quantified targets, limiting power density of artificial lighting installed inside buildings. The present opportunity, generated by the need to carry out the revision of Portuguese building energy systems regulation, should be used to fill the existing gap in national legislation regarding those matters. In this paper the authors present some proposals for future legislation that will have as central purpose the utilization of efficient lighting systems and the promotion of architectural solutions that optimize the use of daylighting. It is possible, and desirable, to add new directives to national legislation that contribute to the improvement of Portuguese buildings, characterized by its good performance in terms of daylight availability, and at the same time, increasing the energy efficiency and reducing the energy consumption of lighting systems installed in those buildings. - Highlights: • In the Portuguese legislation there are no rules concerning the use of daylight. • Lack of specific regulation limiting power density of artificial lighting. • Revision of Portuguese building energy systems regulation. • Some proposals for future legislation. • Improvement of Portuguese buildings promoting energy efficiency

Energy-Efficiency Labels and Standards: A Guidebook forAppliances, Equipment, and Lighting - 2nd Edition

Energy Technology Data Exchange (ETDEWEB)

Wiel, Stephen; McMahon, James E.

2005-04-28

Energy-performance improvements in consumer products are an essential element in any government's portfolio of energy-efficiency and climate change mitigation programs. Governments need to develop balanced programs, both voluntary and regulatory, that remove cost-ineffective, energy-wasting products from the marketplace and stimulate the development of cost-effective, energy-efficient technology. Energy-efficiency labels and standards for appliances, equipment, and lighting products deserve to be among the first policy tools considered by a country's energy policy makers. The U.S. Agency for International Development (USAID) and several other organizations identified on the cover of this guidebook recognize the need to support policy makers in their efforts to implement energy-efficiency standards and labeling programs and have developed this guidebook, together with the Collaborative Labeling and Appliance Standards Program (CLASP), as a primary reference. This second edition of the guidebook was prepared over the course of the past year, four years after the preparation of the first edition, with a significant contribution from the authors and reviewers mentioned previously. Their diligent participation helps maintain this book as the international guidance tool it has become. The lead authors would like to thank the members of the Communications Office of the Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory for their support in the development, production, and distribution of the guidebook. This guidebook is designed as a manual for government officials and others around the world responsible for developing, implementing, enforcing, monitoring, and maintaining labeling and standards setting programs. It discusses the pros and cons of adopting energy-efficiency labels and standards and describes the data, facilities, and institutional and human resources needed for these programs. It provides guidance on the design

The impact of clerestory lights on energy efficiency of buildings

Directory of Open Access Journals (Sweden)

Đenadić Dalibor M.

2015-01-01

Full Text Available The buildings are among major energy consumers, whose energy efficiency is rather low. Clerestory windows are responsible for a large portion of energy losses from the buildings. The energy efficiency of buildings can greatly be improved by upgrading clerestory and other windows. This paper focuses on the theoretical and experimental investigations on how this can be performed in an old school building in the town of Bor in eastern part of Serbia. For that purpose a modern measuring technique has been applied to identify the existing status, and to compare theoretical and actual conditions.

Emerging Energy-Efficient Technologies in Buildings Technology Characterizations for Energy Modeling

Energy Technology Data Exchange (ETDEWEB)

Hadley, SW

2004-10-11

The energy use in America's commercial and residential building sectors is large and growing. Over 38 quadrillion Btus (Quads) of primary energy were consumed in 2002, representing 39% of total U.S. energy consumption. While the energy use in buildings is expected to grow to 52 Quads by 2025, a large number of energy-related technologies exist that could curtail this increase. In recent years, improvements in such items as high efficiency refrigerators, compact fluorescent lights, high-SEER air conditioners, and improved building shells have all contributed to reducing energy use. Hundreds of other technology improvements have and will continue to improve the energy use in buildings. While many technologies are well understood and are gradually penetrating the market, more advanced technologies will be introduced in the future. The pace and extent of these advances can be improved through state and federal R&D. This report focuses on the long-term potential for energy-efficiency improvement in buildings. Five promising technologies have been selected for description to give an idea of the wide range of possibilities. They address the major areas of energy use in buildings: space conditioning (33% of building use), water heating (9%), and lighting (16%). Besides describing energy-using technologies (solid-state lighting and geothermal heat pumps), the report also discusses energy-saving building shell improvements (smart roofs) and the integration of multiple energy service technologies (CHP packaged systems and triple function heat pumps) to create synergistic savings. Finally, information technologies that can improve the efficiency of building operations are discussed. The report demonstrates that the United States is not running out of technologies to improve energy efficiency and economic and environmental performance, and will not run out in the future. The five technology areas alone can potentially result in total primary energy savings of between 2 and

Saving money vs investing money: Do energy ratings influence consumer demand for energy efficient goods?

International Nuclear Information System (INIS)

Panzone, Luca A.

2013-01-01

The article analyses economic barriers leading to the energy efficiency gap in the market for energy-using products by observing several million transactions in the UK over two years. The empirical exercise estimates AIDS models for refrigerators, washing machines, TVs, and light bulbs. Results indicate that market barriers are crucial in the demand for energy efficient options, and consumer response to changes in appliance prices, total expenditures, and energy prices depends on the possibility of behavioural adjustments in consumption. In contrast with the induced innovation hypothesis, current electricity prices can fail to induce innovation because of their short-term impact on disposable income, while consumers invest in energy efficiency when expecting electricity prices to rise in the future. - Highlights: • The article analyses economic barriers to energy efficiency in the UK. • Data refers to 2-year sales of refrigerators, washing machines, TV, and light bulbs. • Demand parameters by efficiency rating are estimated from four AIDS models. • Future (not present) electricity prices induce investments in energy efficiency. • Behavioural efficiency adjustments explain differences in market response

Scalable Light Module for Low-Cost, High-Efficiency Light- Emitting Diode Luminaires

Energy Technology Data Exchange (ETDEWEB)

Tarsa, Eric [Cree, Inc., Goleta, CA (United States)

2015-08-31

During this two-year program Cree developed a scalable, modular optical architecture for low-cost, high-efficacy light emitting diode (LED) luminaires. Stated simply, the goal of this architecture was to efficiently and cost-effectively convey light from LEDs (point sources) to broad luminaire surfaces (area sources). By simultaneously developing warm-white LED components and low-cost, scalable optical elements, a high system optical efficiency resulted. To meet program goals, Cree evaluated novel approaches to improve LED component efficacy at high color quality while not sacrificing LED optical efficiency relative to conventional packages. Meanwhile, efficiently coupling light from LEDs into modular optical elements, followed by optimally distributing and extracting this light, were challenges that were addressed via novel optical design coupled with frequent experimental evaluations. Minimizing luminaire bill of materials and assembly costs were two guiding principles for all design work, in the effort to achieve luminaires with significantly lower normalized cost ($/klm) than existing LED fixtures. Chief project accomplishments included the achievement of >150 lm/W warm-white LEDs having primary optics compatible with low-cost modular optical elements. In addition, a prototype Light Module optical efficiency of over 90% was measured, demonstrating the potential of this scalable architecture for ultra-high-efficacy LED luminaires. Since the project ended, Cree has continued to evaluate optical element fabrication and assembly methods in an effort to rapidly transfer this scalable, cost-effective technology to Cree production development groups. The Light Module concept is likely to make a strong contribution to the development of new cost-effective, high-efficacy luminaries, thereby accelerating widespread adoption of energy-saving SSL in the U.S.

Understanding energy efficient lighting as an outcome of dynamics of social practices

DEFF Research Database (Denmark)

Jensen, Charlotte Louise

2017-01-01

In policy-making, reducing energy consumption from lighting is largely treated as a matter of optimizing products. However, since lighting is a highly cultural and socio-material phenomenon, this article argues that current ways of using light cannot be attributed to the properties of the light s...

Energy efficiency buildings program, FY 1980

Energy Technology Data Exchange (ETDEWEB)

1981-05-01

A separate abstract was prepared on research progress in each group at LBL in the energy efficient buildings program. Two separate abstracts were prepared for the Windows and Lighting Program. Abstracts prepared on other programs are: Energy Performance of Buildings; Building Ventilation and Indoor Air Quality Program; DOE-21 Building Energy Analysis; and Building Energy Data Compilation, Analysis, and Demonstration. (MCW)

Complex photonic structures for energy efficiency

Directory of Open Access Journals (Sweden)

Wiersma D. S.

2013-06-01

Full Text Available Photonic structures are playing an increasingly important role in energy efficiency. In particular, they can help to control the flow of light and improve the optical properties of photovoltaic solar cells. We will explain the physics of light transport in such structures with a special focus on disordered materials.

Design of High Efficiency Illumination for LED Lighting

OpenAIRE

Chang, Yong-Nong; Cheng, Hung-Liang; Kuo, Chih-Ming

2013-01-01

A high efficiency illumination for LED street lighting is proposed. For energy saving, this paper uses Class-E resonant inverter as main electric circuit to improve efficiency. In addition, single dimming control has the best efficiency, simplest control scheme and lowest circuit cost among other types of dimming techniques. Multiple serial-connected transformers used to drive the LED strings as they can provide galvanic isolation and have the advantage of good current distribution against de...

Climate change mitigation through energy efficiency : opportunities in Atlantic Canada

International Nuclear Information System (INIS)

Cote, R.; Archibald, G.

2008-01-01

Canada's total energy use is expected to increase by 20 per cent between 2005 and 2020. Studies have suggested that successful energy efficiency initiatives could reduce growth in demand by up to 50 per cent, while reducing greenhouse gases (GHGs) by an estimated 40 per cent. Energy use comprises approximately 65.4 per cent of total expenditures for most businesses. Atlantic region industries contribute nearly 7 per cent of Canadian industrial energy consumption while contributing 5 per cent to the Canadian industrial gross domestic product (GDP). Energy efficiency practices adopted by industry operators in the Maritimes included modifications to boilers, process cooling equipment, motors, compressed air equipment, lighting and HVAC systems. Energy efficiency performance values in the Maritimes range from 11 to 100 per cent, with an average of 65 per cent. Opportunities for improving energy efficiency include inefficient lighting, leaking faucets, poor heat distribution, and inappropriate solid waste segregation. Cost savings for various energy efficiency measures were presented. Case studies of various eco-efficiency programs conducted at plants and businesses in the Maritimes were also included. tabs., figs.

Energy efficiency in the world and Turkey and investigation of energy efficiency in Turkish Industry

International Nuclear Information System (INIS)

Kavak, K.

2005-09-01

The reserves of fossil fuels which currently respond to the major part of world energy requirements are being running out very fast. Because it is forecasted that reserves of some fossil fuels like oil and natural gas will come to an end in the second half of this century, exploiting all energy resources in an efficient manner has great importance. Throughout the world where the energy demand grows continuously but the resources decrease gradually, many types of programs are implemented to provide efficient energy use. In Turkey, although there have been some efforts in last two decades, the importance of the issue could not be undersood yet. Turkey'sgeneral energy policy still focuses on supply security and finding ways to meet the growing demand, rather than decreasing the demand by energy efficiency. In this study, the possible opportunities and benefits that Turkey would gain by energy efficiency is pointed out. The studies about energy efficiency which have been conducted in the world and Turkey are examined. The measurement that can be taken in the sectors such as industry, power plants, buildings, transportation and the utilities of these measures for energy economy are indicated. The successful practices of energy efficiency studies in various countries, the state of some countries which pioneer efficiency implementations. Turkey's situation in energy in the light of basic indicators such as energy consumption per capita and enrgy intensity, the energy efficiency studies that have been done and should be done in various sectors of Turkey are also discussed in this thesis. Turkish industry's energy comsumption is analyzed as a seperate chapter by taking into consideration energy efficiency, energy intensity and energy resources. The general energy consumption and energy intensity tendencies of main manufacturing industries between 1995 and 2002 are explored and resource utilization ratios are investigated. This chapter provides to find out what kind of

Optimization of emission color and efficiency of organic light emitting diodes for lighting applications

Energy Technology Data Exchange (ETDEWEB)

Seidel, Stefan; Krause, Ralf [Department of Materials Science VI, University of Erlangen-Nuernberg (Germany); Siemens AG, CT MM 1, Erlangen (Germany); Kozlowski, Fryderyk; Schmid, Guenter; Hunze, Arvid [Siemens AG, CT MM 1, Erlangen (Germany); Winnacker, Albrecht [Department of Materials Science VI, University of Erlangen-Nuernberg (Germany)

2008-07-01

In recent years the performance of organic light emitting diodes (OLEDs) has reached a level where OLED lighting presents an interesting application target. Research activities therefore focus amongst other things on the development of high efficient and stable white light emitting devices. We demonstrate how the color coordinates can be adjusted to achieve a warm white emission spectrum, whereas the OLED stack contains phosphorescent red and green dyes combined with a fluorescent blue one. Detailed results are presented with respect to a variation of layer thicknesses and dopant concentrations of the emission layers. Furthermore the influence of various dye molecules and hence different energy level alignments between host and dopants on color and efficiency will be discussed.

China's energy efficiency target 2010

International Nuclear Information System (INIS)

Yang Ming

2008-01-01

The Chinese government has set an ambitious target: reducing China's energy intensity by 20%, or 4.36% each year between 2006 and 2010 on the 2005 level. Real data showed that China missed its target in 2006, having reduced its energy intensity only by 1.3%. The objective of this study is to evaluate the feasibility and potential of the Chinese to achieve the target. This paper presents issues of macro-economy, population migration, energy savings, and energy efficiency policy measures to achieve the target. A top-down approach was used to analyse the relationship between the Chinese economic development and energy demand cycles and to identify the potentials of energy savings in sub-sectors of the Chinese economy. A number of factors that contribute to China's energy intensity are identified in a number of energy-intensive sectors. This paper concludes that China needs to develop its economy at its potential GDP growth rate; strengthen energy efficiency auditing, monitoring and verification; change its national economy from a heavy-industry-dominated mode to a light industry or a commerce-dominated mode; phase out inefficient equipment in industrial sectors; develop mass and fast railway transportation; and promote energy-efficient technologies at the end use. This paper transfers key messages to policy makers for designing their policy to achieve China's energy efficiency target

Evaluation and Improvement of Lighting Efficiency in Working Spaces

Directory of Open Access Journals (Sweden)

Ana Castillo-Martinez

2018-04-01

Full Text Available Lighting is an essential element for modern life, promoting a sense of wellbeing for users. However, bad illumination may produce health problems such as headaches and fatigue, among other vision problems. For that reason, this paper proposes the development of a smartphone-based application to help in lighting evaluation to guarantee the compliance of illumination regulations and to help increase illuminance efficiency, reducing its energy consumption. To perform this evaluation, the smartphone can be used as a lighting measurement tool, evaluating those measurements through an intelligent agent based in rules capable of guiding the decision-making process. As a result, this tool allows the evaluation of the real working environment to guarantee lighting requirements, helping in the prevention of health problems derived from bad illumination and improving the lighting efficiency at the same time.

Questions asked concerning energy savings in lighting systems

International Nuclear Information System (INIS)

Bernet, J.

2005-01-01

This article discusses the question why information on the power consumption of lighting fixtures is not often to be found in articles in lifestyle magazines or in the displays of designer-boutiques. The efficiency of various types of lighting is discussed. In particular, the differences between traditional incandescent bulbs and energy-saving lighting systems are examined from the aesthetical, colour-reproduction and energy-consumption points of view. Further information presented includes details on colour-reproduction indexes and colour temperature. The lighting needs of various types of room are looked at and the influence of the physical form of the lighting fixtures on purchasing decisions is examined

Initiative EnergieEffizienz : An information campaign on energy efficiency for private households

International Nuclear Information System (INIS)

Agricola, Annegret-Cl.; Ahrens, Wiebke

2005-01-01

Unnecessary energy consumption can be avoided easily by making intelligent decisions when buying and using household equipment and hence cut the electricity bill and reduce carbon dioxide emissions. This is the key message imparted by the information campaign on energy efficiency for private households. The campaign addresses three main topics: the reduction or avoidance of stand by energy consumption of consumer electronics and IT-equipment, energy efficient high quality lighting and energy efficiency in the white goods sector. Consumers are addressed via a broad range of communication measures highlighting the efficiency issue. These instruments include advertisement in nationwide print media, regular press releases, public relations activities etc. Special information material are made for young people as well as for the Turkish minority in Germany. The main strategy of the campaign is to co-operate with retailers: consumers are to gain information on energy efficiency at the point of sale where domestic appliances and lighting equipment are sold. The campaign offers information for the point of sale including brochures for customers as well as for sales assistants. By December 2004 approximately 7,200 points of sale all over in Germany were equipped with the campaign's information. The German national energy agency (dena) runs the information campaign in co-operation with the German associations of power suppliers, the German foundation for environmental protection and the Federal Ministry of Economy and Labour. The campaign started in 2002. Its aims are to arise consumers' awareness, to inform consumers on energy efficient appliances and give motivation when buying and using them. Through these aims the campaign should contribute to reduce carbon dioxide emissions in the private sector In order to measure the campaign's impact a quantitative analysis is carried out. First results show a change in public's awareness and attitude towards energy efficiency

Improving the Efficiency of Solid State Light Sources

International Nuclear Information System (INIS)

Joanna McKittrick

2003-01-01

This proposal addresses the national need to develop a high efficiency light source for general illumination applications. The goal is to perform research that would lead to the fabrication of a unique solid state, white-emitting light source. This source is based on an InGaN/GaN UV-emitting chip that activates a luminescent material (phosphor) to produce white light. White-light LEDs are commercially available which use UV from a GaN chip to excite a phosphor suspended in epoxy around the chip. Currently, these devices are relatively inefficient. This research will target one technical barrier that presently limits the efficiency of GaN based devices. Improvements in efficiencies will be achieved by improving the internal conversion efficiency of the LED die, by improving the coupling between the die and phosphor(s) to reduce losses at the surfaces, and by selecting phosphors to maximize the emissions from the LEDs in conversion to white light. The UCSD research team proposes for this project to develop new phosphors that have high quantum efficiencies that can be activated by the UV-blue (360-410 nm) light emitted by the GaN device. The main goal for the UCSD team was to develop new phosphor materials with a very specific property: phosphors that could be excited at long UV-wavelengths (λ=350-410 nm). The photoluminescence of these new phosphors must be activated with photons emitted from GaN based dies. The GaN diodes can be designed to emit UV-light in the same range (λ=350-410 nm). A second objective, which is also very important, is to search for alternate methods to fabricate these phosphors with special emphasis in saving energy and time and reduce pollution

Mechanisms of Light Energy Harvesting in Dendrimers and Hyperbranched Polymers

Directory of Open Access Journals (Sweden)

David L. Andrews

2011-12-01

Full Text Available Since their earliest synthesis, much interest has arisen in the use of dendritic and structurally allied forms of polymer for light energy harvesting, especially as organic adjuncts for solar energy devices. With the facility to accommodate a proliferation of antenna chromophores, such materials can capture and channel light energy with a high degree of efficiency, each polymer unit potentially delivering the energy of one photon—or more, when optical nonlinearity is involved. To ensure the highest efficiency of operation, it is essential to understand the processes responsible for photon capture and channelling of the resulting electronic excitation. Highlighting the latest theoretical advances, this paper reviews the principal mechanisms, which prove to involve a complex interplay of structural, spectroscopic and electrodynamic properties. Designing materials with the capacity to capture and control light energy facilitates applications that now extend from solar energy to medical photonics.

Investigation of Electrical Energy Efficiency Use in an Automobile Assembly Industry

Directory of Open Access Journals (Sweden)

Jacob TSADO

2016-12-01

Full Text Available This research work investigated the electrical energy efficiency improvement and cost saving potentials for automobile assembly plant; a case of Peugeot Automobile Nigeria Limited. The study identified lighting system as a major source through which energy is being wasted, hence efficient energy saving lighting systems are being proffered; also saving accrued were determined to justify their deployment. In the course of this work, an energy saving calculating tool was developed to calculate energy saving capabilities using energy efficient lamps. With ample devotion to the implementation of the recommendations made, the cost of energy per car will be drastically reduced while profits are also made simultaneously. In all, more cars will be produced thus translating to more employment opportunities in the industry.

Efficiency simulations of thin film chalcogenide photovoltaic cells for different indoor lighting conditions

International Nuclear Information System (INIS)

Minnaert, B.; Veelaert, P.

2011-01-01

Photovoltaic (PV) energy is an efficient natural energy source for outdoor applications. However, for indoor applications, the efficiency of PV cells is much lower. Typically, the light intensity under artificial lighting conditions is less than 10 W/m 2 as compared to 100-1000 W/m 2 under outdoor conditions. Moreover, the spectrum is different from the outdoor solar spectrum. In this context, the question arises whether thin film chalcogenide photovoltaic cells are suitable for indoor use. This paper contributes to answering that question by comparing the power output of different thin film chalcogenide solar cells with the classical crystalline silicon cell as reference. The comparisons are done by efficiency simulation based on the quantum efficiencies of the solar cells and the light spectra of typical artificial light sources i.e. an LED lamp, a 'warm' and a 'cool' fluorescent tube and a common incandescent and halogen lamp, which are compared to the outdoor AM 1.5 spectrum as reference.

78 FR 16443 - Energy Efficiency Program for Consumer Products: Energy Conservation Standards for Ceiling Fans...

Science.gov (United States)

2013-03-15

... Standards for Ceiling Fans and Ceiling Fan Light Kits AGENCY: Office of Energy Efficiency and Renewable... consider amending the energy conservation standards for ceiling fans and ceiling fan light kits. DOE also....gov . Follow the instructions for submitting comments. Email: CeilingFan[email protected

A SOFTWARE PRODUCT LINE FOR ENERGY-EFFICIENT CONTROL OF SUPPLEMENTARY LIGHTING IN GREENHOUSES

DEFF Research Database (Denmark)

Mærsk-Møller, Hans Martin; Jørgensen, Bo Nørregaard

2011-01-01

of 2009 – 2010 showed 25 percent savings with no negative effect on plant quality. To accelerate the impact of our approach, we chose to use Software Product Line Engineering, as it enables a greater variety of related software tools to be created faster. We have created a web-based analysis tool, Dyna...... preserving production quality. This paper presents a novel approach addressing this issue. We use weather forecasts and electricity prices to compute cost- and energy-efficient supplementary light plans that achieve the required plant growth defined by the grower. Experiments performed during the winter...... of these two tools is described together with the lessons learned from using Software Product Line Engineering in the domain of greenhouse software development....

The E-bike : opportunities for commuter traffic. The potentials of using electric bicycles and –scooters in commuting traffic in relation to energy use, local emissions and the accessibility of a compact Dutch city

NARCIS (Netherlands)

Engelmoer, Wiebe

2012-01-01

SUMMARY The electric bicycle and -scooter are entering the personal mobility market quickly due to a number of advantages over conventional modes of personal mobility. However, the effects of this relative new mode of transport are quite unknown. Therefo

Flow of light energy in benthic photosynthetic microbial mats

Energy Technology Data Exchange (ETDEWEB)

Al-Najjar, Mohammad Ahmad A.

2010-12-15

The work in this thesis demonstrates the assessment of the energy budget inside microbial mat ecosystems, and the factors affecting light utilization efficiency. It presents the first balanced light energy budget for benthic microbial mat ecosystems, and shows how the budget and the spatial distribution of the local photosynthetic efficiencies within the euphotic zone depend on the absorbed irradiance (Jabs). The energy budget was dominated by heat dissipation on the expense of photosynthesis. The maximum efficiency of photosynthesis was at light limiting conditions When comparing three different marine benthic photosynthetic ecosystems (originated from Abu-Dhabi, Arctic, and Exmouth Gulf in Western Australia), differences in the efficiencies were calculated. The results demonstrated that the maximum efficiency depended on mat characteristics affecting light absorption and scattering; such as, photopigments ratio and distribution, and the structural organization of the photosynthetic organisms relative to other absorbing components of the ecosystem (i.e., EPS, mineral particles, detritus, etc.). The maximum efficiency decreased with increasing light penetration depth, and increased with increasing the accessory pigments (phycocyanin and fucoxanthin)/chlorophyll ratio. Spatial heterogeneity in photosynthetic efficiency, pigment distribution, as well as light acclimation in microbial mats originating from different geographical locations was investigated. We used a combined pigment imaging approach (variable chlorophyll fluorescence and hyperspectral imaging), and fingerprinting approach. For each mat, the photosynthetic activity was proportional to the local pigment concentration in the photic zone, but not for the deeper layers and between different mats. In each mat, yield of PSII and E1/2 (light acclimation) generally decreased in parallel with depth, but the gradients in both parameters varied greatly between samples. This mismatch between pigments concentration

Energy transfer and clustering of photosynthetic light-harvesting complexes in reconstituted lipid membranes

International Nuclear Information System (INIS)

Dewa, Takehisa; Sumino, Ayumi; Watanabe, Natsuko; Noji, Tomoyasu; Nango, Mamoru

2013-01-01

Highlights: ► Photosynthetic light-harvesting complexes were reconstituted into lipid membranes. ► Energy transfers between light-harvesting complexes were examined. ► Atomic force microscopy indicated cluster formation of light-harvesting complexes. ► Efficient energy transfer was observed for the clustered complexes in the membranes. - Abstract: In purple photosynthetic bacteria, light-harvesting complex 2 (LH2) and light harvesting/reaction centre core complex (LH1-RC) play the key roles of capturing and transferring light energy and subsequent charge separation. These photosynthetic apparatuses form a supramolecular assembly; however, how the assembly influences the efficiency of energy conversion is not yet clear. We addressed this issue by evaluating the energy transfer in reconstituted photosynthetic protein complexes LH2 and LH1-RC and studying the structures and the membrane environment of the LH2/LH1-RC assemblies, which had been embedded into various lipid bilayers. Thus, LH2 and LH1-RC from Rhodopseudomonas palustris 2.1.6 were reconstituted in phosphatidylglycerol (PG), phosphatidylcholine (PC), and phosphatidylethanolamine (PE)/PG/cardiolipin (CL). Efficient energy transfer from LH2 to LH1-RC was observed in the PC and PE/PG/CL membranes. Atomic force microscopy revealed that LH2 and LH1-RC were heterogeneously distributed to form clusters in the PC and PE/PG/CL membranes. The results indicated that the phospholipid species influenced the cluster formation of LH2 and LH1-RC as well as the energy transfer efficiency

Energy transfer and clustering of photosynthetic light-harvesting complexes in reconstituted lipid membranes

Energy Technology Data Exchange (ETDEWEB)

Dewa, Takehisa, E-mail: takedewa@nitech.ac.jp [Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Japan Science and Technology, PRESTO, 4-1-8 Honcho Kawaguchi, Saitama 332-0012 (Japan); Sumino, Ayumi; Watanabe, Natsuko; Noji, Tomoyasu [Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Nango, Mamoru, E-mail: nango@nitech.ac.jp [Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan)

2013-06-20

Highlights: ► Photosynthetic light-harvesting complexes were reconstituted into lipid membranes. ► Energy transfers between light-harvesting complexes were examined. ► Atomic force microscopy indicated cluster formation of light-harvesting complexes. ► Efficient energy transfer was observed for the clustered complexes in the membranes. - Abstract: In purple photosynthetic bacteria, light-harvesting complex 2 (LH2) and light harvesting/reaction centre core complex (LH1-RC) play the key roles of capturing and transferring light energy and subsequent charge separation. These photosynthetic apparatuses form a supramolecular assembly; however, how the assembly influences the efficiency of energy conversion is not yet clear. We addressed this issue by evaluating the energy transfer in reconstituted photosynthetic protein complexes LH2 and LH1-RC and studying the structures and the membrane environment of the LH2/LH1-RC assemblies, which had been embedded into various lipid bilayers. Thus, LH2 and LH1-RC from Rhodopseudomonas palustris 2.1.6 were reconstituted in phosphatidylglycerol (PG), phosphatidylcholine (PC), and phosphatidylethanolamine (PE)/PG/cardiolipin (CL). Efficient energy transfer from LH2 to LH1-RC was observed in the PC and PE/PG/CL membranes. Atomic force microscopy revealed that LH2 and LH1-RC were heterogeneously distributed to form clusters in the PC and PE/PG/CL membranes. The results indicated that the phospholipid species influenced the cluster formation of LH2 and LH1-RC as well as the energy transfer efficiency.

Energy Efficiency for the Nunamiut People

Energy Technology Data Exchange (ETDEWEB)

Goodman, Dan

2014-04-09

The goal of this project is to upgrade existing building facilities owned by Nunamiut Corporation in Anaktuvuk Pass, AK. The upgrades mentioned will include lighting, heating system, insulation and smart control units designed to increase the energy efficiency of Village Corporation owned buildings.

Operational efficiency of the lighting system of bus salons

Directory of Open Access Journals (Sweden)

Brytkovskyi V.M.

2016-08-01

Full Text Available In recent years the problem of safety of people is studied primarily in aspects of natural and man-made disasters, fire, health and safety in the workplace. A problem connected with the way of life of the people, in particular with the use of bus transport remains almost out of sight. In addition to the foregoing, there is another side to the issue: modern development of industry and transport is characterized by large-scale introduction of technical measures aimed at saving energy In the specified aspect theoretical dependences for evaluation of technological economic efficiency of light sources in indoor lighting system buses are grounded. This theoretical dependency will make analytical framework justification applying the respective sources of light, taking into account the hygiene requirements to illumination. The methodology of calculation of economic efficiency of lighting of bus salons is offered. Estimating parameter is justified relative objective function value costs per unit of time or distance. The greatest costs are typical for lamps with incandescent bulbs. The least is common to lamps with fluorescent lamps. Led bulbs have no significant advantage even over incandescent lamps. The reason for this is the relatively high color temperature radiation of LED lamps that requires more light levels and, consequently, the high cost of energy, as well as relatively large initial cost of these lamps.

The selection of flying roller as an effort to increase the power of scooter-matic as the main power of centrifugal pump for fire fighter motor cycle

Science.gov (United States)

Hadi Sutrisno, Himawan

2018-03-01

In densely populated settlements, fires often occur and cause losses. In some instances, the process of the occurrence of fires takes place so quickly that to reduce and avoid the occurrence of a fire disaster effort is required in accordance with the existing environmental condition. Fire fighter motorcycle by using motorcycle scooter-matic is considered suitable as one alternative to combating fire hazard in densely populated residential settlements. The use of motorcycle engines as the driving force of the pump often leads to unstable and not optimum power. Thus, the water spray on the centrifugal pump also becomes not maximum. To increase the engine power at scooter-matic engine idle rotation (700-2000 rpm), then the flying roller replacement with certain mass weight becomes an option. By selecting a 10 to 14 gram flying roller mass, the power analysis using a dynotest engine produces several variations. Of the calculation, the mass of a 14 gram flying roller provides a significant increase in motor power on the upper rotation. Meanwhile, on the lower power rotation using a flying roller with a mass of 10 grams provides an increase in power compared to a standard flying roller on a scooter matic motor engine. As a reference to the use of scooter-matic motor power as the pump power, the result of use of the flying roller with a mass of 10 grams becomes the best option.

Solid-state lighting: an energy-economics perspective

International Nuclear Information System (INIS)

Tsao, J Y; Creighton, J R; Coltrin, M E; Simmons, J A; Saunders, H D

2010-01-01

Artificial light has long been a significant factor contributing to the quality and productivity of human life. As a consequence, we are willing to use huge amounts of energy to produce it. Solid-state lighting (SSL) is an emerging technology that promises performance features and efficiencies well beyond those of traditional artificial lighting, accompanied by potentially massive shifts in (a) the consumption of light, (b) the human productivity and energy use associated with that consumption and (c) the semiconductor chip area inventory and turnover required to support that consumption. In this paper, we provide estimates of the baseline magnitudes of these shifts using simple extrapolations of past behaviour into the future. For past behaviour, we use recent studies of historical and contemporary consumption patterns analysed within a simple energy-economics framework (a Cobb-Douglas production function and profit maximization). For extrapolations into the future, we use recent reviews of believed-achievable long-term performance targets for SSL. We also discuss ways in which the actual magnitudes could differ from the baseline magnitudes of these shifts. These include: changes in human societal demand for light; possible demand for features beyond lumens; and guidelines and regulations aimed at economizing on consumption of light and associated energy.

Solid-state lighting: an energy-economics perspective

Energy Technology Data Exchange (ETDEWEB)

Tsao, J Y; Creighton, J R; Coltrin, M E; Simmons, J A [Physical, Chemical and Nano Sciences Center, Sandia National Laboratories, PO Box 5800, Albuquerque, NM 87185-0601 (United States); Saunders, H D, E-mail: jytsao@sandia.go, E-mail: jrcreig@sandia.go, E-mail: mecoltr@sandia.go, E-mail: jsimmon@sandia.go, E-mail: hsaunders@decisionprocessesinc.co [Decision Processes Incorporated, 2308 Saddleback Drive, Danville, CA 94506 (United States)

2010-09-08

Artificial light has long been a significant factor contributing to the quality and productivity of human life. As a consequence, we are willing to use huge amounts of energy to produce it. Solid-state lighting (SSL) is an emerging technology that promises performance features and efficiencies well beyond those of traditional artificial lighting, accompanied by potentially massive shifts in (a) the consumption of light, (b) the human productivity and energy use associated with that consumption and (c) the semiconductor chip area inventory and turnover required to support that consumption. In this paper, we provide estimates of the baseline magnitudes of these shifts using simple extrapolations of past behaviour into the future. For past behaviour, we use recent studies of historical and contemporary consumption patterns analysed within a simple energy-economics framework (a Cobb-Douglas production function and profit maximization). For extrapolations into the future, we use recent reviews of believed-achievable long-term performance targets for SSL. We also discuss ways in which the actual magnitudes could differ from the baseline magnitudes of these shifts. These include: changes in human societal demand for light; possible demand for features beyond lumens; and guidelines and regulations aimed at economizing on consumption of light and associated energy.

Highly efficient white top-emitting organic light-emitting diodes with forward directed light emission

Energy Technology Data Exchange (ETDEWEB)

Freitag, Patricia; Reineke, Sebastian; Furno, Mauro; Luessem, Bjoern; Leo, Karl [Institut fuer Angewandte Photophysik, TU Dresden (Germany)

2010-07-01

The demand for highly efficient and energy saving illumination has increased considerably during the last decades. Organic light emitting diodes (OLEDs) are promising candidates for future lighting technologies. They offer high efficiency along with excellent color quality, allowing substantially lower power consumption than traditional illuminants. Recently, especially top-emitting devices have attracted high interest due to their compatibility with opaque substrates like metal sheets. In this contribution, we demonstrate top-emitting OLEDs with white emission spectra employing a multilayer hybrid cavity structure with two highly efficient phosphorescent emitter materials for orange-red (Ir(MDQ)2(acac)) and green (Ir(ppy)3) emission as well as the stable fluorescent blue emitter TBPe. To improve the OLED performance and modify the color quality, two different electron blocking layers and anode material combinations are tested. Compared to Lambertian emission, our devices show considerably enhanced forward emission, which is preferred for most lighting applications. Besides broadband emission and angle independent emission maxima, power efficiencies of 13.3 lm/W at 3 V and external quantum efficiencies of 5.3% are achieved. The emission shows excellent CIE coordinates of (0.420,0.407) at approx. 1000 cd/m{sup 2} and color rendering indices up to 77.

Energy efficiency evaluation of hospital building office

Science.gov (United States)

Fitriani, Indah; Sangadji, Senot; Kristiawan, S. A.

2017-01-01

One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings.

Energy efficiency evaluation of hospital building office

International Nuclear Information System (INIS)

Fitriani, Indah; Sangadji, Senot; Kristiawan, S.A.

2017-01-01

One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings. (paper)

Transfer of ultraviolet photon energy into fluorescent light in the visible path represents a new and efficient protection mechanism of sunscreens

Science.gov (United States)

Vergou, Theognosia; Patzelt, Alexa; Richter, Heike; Schanzer, Sabine; Zastrow, Leonhard; Golz, Karin; Doucet, Olivier; Antoniou, Christina; Sterry, Wolfram; Lademann, Juergen

2011-10-01

The development of sunscreens with high sun protection factor (SPF) values but low filter concentrations is the ultimate goal. The purpose of the present study was to investigate why a sunscreen spray and cream with different concentrations of the same UV-filters provided the same SPF. Therefore, the homogeneity of the distribution of both sunscreens was investigated by laser scanning microscopy (LSM) and tape stripping (TS). Additionally, the energy transfer mechanisms of the sunscreens on the skin were analyzed. The TS and LSM showed a better homogeneity of the distribution of the spray. With Wood's light, a total absorption of the irradiation was detected in the spray area. In contrast, after cream treatment, an intensive fluorescent signal was observed. It was demonstrated that this fluorescent signal was caused by nonthermal energy transferred from the UV-filters to one compound of the cream releasing its excitation energy by fluorescence. This nonthermal energy transfer seemed to be the reason for the high efficiency of the cream, which is subjected to thermal relaxation. The transfer of UV photon energy into fluorescent light represents a new approach to increase the efficiency of sunscreens and could form the basis for a new generation of sunscreens.

Evaluation and Improvement of Lighting Efficiency in Working Spaces

OpenAIRE

Ana Castillo-Martinez; Jose-Amelio Medina-Merodio; Jose-Maria Gutierrez-Martinez; Juan Aguado-Delgado; Carmen de-Pablos-Heredero; Salvador Otón

2018-01-01

Lighting is an essential element for modern life, promoting a sense of wellbeing for users. However, bad illumination may produce health problems such as headaches and fatigue, among other vision problems. For that reason, this paper proposes the development of a smartphone-based application to help in lighting evaluation to guarantee the compliance of illumination regulations and to help increase illuminance efficiency, reducing its energy consumption. To perform this evaluation, the smartph...

Design of High Efficiency Illumination for LED Lighting

Directory of Open Access Journals (Sweden)

Yong-Nong Chang

2013-01-01

Full Text Available A high efficiency illumination for LED street lighting is proposed. For energy saving, this paper uses Class-E resonant inverter as main electric circuit to improve efficiency. In addition, single dimming control has the best efficiency, simplest control scheme and lowest circuit cost among other types of dimming techniques. Multiple serial-connected transformers used to drive the LED strings as they can provide galvanic isolation and have the advantage of good current distribution against device difference. Finally, a prototype circuit for driving 112 W LEDs in total was built and tested to verify the theoretical analysis.

Measuring Energy Efficiency in China’s Transport Sector

Directory of Open Access Journals (Sweden)

Han Hao

2017-05-01

Full Text Available Energy efficiency is one of the key factors affecting energy consumption and greenhouse gas (GHG emissions. By focusing on China’s transport sector, this study comprehensively reviews and compares the energy efficiency performance of passenger vehicles, light-duty commercial vehicles, commercial road transport, commercial water transport, aviation transport and railway transport, and identifies the opportunities for further energy efficiency improvements. It is found that railway transport exhibited the greatest improvement in energy efficiency during the past decade, which was mainly driven by progress in its electrification. Passenger vehicles have also experienced considerable energy efficiency improvements, which can be mainly attributed to the establishment of mandatory fuel consumption standards. In contrast, commercial road transport has shown the least improvement, due to insufficient policy implementations. Based on the analysis, it is recommended that, as China’s present policy framework to improve energy efficiency in the transport sector is generally effective, it should be consistently maintained and successively improved. Electrification represents a major opportunity for improvement of energy efficiency in the transport sector. Such potential should be fully tapped for all transport modes. Greater effort should be put into improving the energy efficiency of commercial road transport. The policy instruments utilized to improve the energy efficiency of heavy-duty vehicles should be as intensive and effective as the policy instruments for passenger vehicles.

Energy-efficient operation of a booster RF system for Taiwan light source operated in top-up mode

International Nuclear Information System (INIS)

Yeh, Meng-Shu; Wang, Chaoen; Chang, Lung-Hai; Chung, Fu-Tsai; Yu, Tsung-Chi; Lin, Ming-Chyuan; Chen, Ling-Jhen; Yang, Tz-Te; Chang, Mei-Hsia; Lin, Yu-Han; Tsai, Ming-Hsun; Lo, Chih-Hung; Liu, Zong-Kai

2015-01-01

Contemporary light sources operate in a top-up mode to maintain their photon intensity quasi-constant so as to improve significantly the thermal stability of the photon beam and to maximize ultimately the average photon flux at a designed maximum operational beam current. Operating in a top-up mode requires frequent beam injection from the synchrotron booster to the storage ring of the light source, but the injection intervals occupy only a tiny portion of the operational time of the integrated machine. To maintain a high operational reliability, the booster RF system practically operates necessarily under injection conditions around the clock and consumes full electric power whether during top-up injection or not. How to decrease the power consumption of the booster RF system during its stand-by time but not to sacrifice the reliability and availability of the RF system is obviously of fundamental interest for routine operation of the light source in a top-up mode. Here, an energy-efficient operation of a booster RF system adaptive to top-up operation of a light source is proposed that has been developed, realized and integrated into the booster RF system of the Taiwan Light Source (TLS), and routinely operated since the end of year 2008. The klystron cathode current and RF gap voltage of the booster's accelerating RF cavity are both periodically modulated to adapt the injection rhythm during top-up operation, which results in decreased consumption of electric power of the booster RF system by more than 78%. The impact on the reliability and availability of the booster RF system has been carefully monitored during the past five operational years, delivering more than 5000 h scheduled user beam time per year. The booster RF system retains its excellent reliability and availability as previously. Neither a decrease of the service time nor an induced reliability issue from the klystron or any high-power high-voltage component of the transmitter has been

Effects of substituting energy with capital on China's aggregated energy and environmental efficiency

International Nuclear Information System (INIS)

Yang Mian; Yang Fuxia; Chen Xingpeng

2011-01-01

Substituting energy with capital (SEC) in economic productions has become a common practice both for business owners and policy-makers to improve their energy and environmental efficiency. However, seldom previous studies on energy efficiency and/or environmental performance evaluation took this role into account. This paper aims to shed some light on the effects of SEC on China's aggregated energy and environmental efficiency (AEEE) within a parametric stochastic frontier analysis framework. Moreover, influencing factors of regional efficiency score are also discussed using a pooled regression model. The results indicate that SEC poses significant effects on improving China's AEEE, and this impact appears obvious regional variation that regions with lower efficiency scores hold more extensive potential to improve their AEEE by means of SEC. Furthermore, upgrading industrial structure and decreasing the proportion of coal in energy consumption make great sense to improve China's AEEE. - Highlights: → We examine the effects of substituting energy with capital on China's energy and environmental efficiency. → The efficiency value considering this substitution is higher than that without considering it. → Hebei and Shanxi hold the largest potential of energy saving and SO 2 emissions reduction. → China's energy and environmental efficiency is affected by its energy mix and industrial structure.

Development of Efficient UV-LED Phosphor Coatings for Energy Saving Solid State Lighting

International Nuclear Information System (INIS)

Uwe Happek

2006-01-01

The University of Georgia, in collaboration with GE Global Research, has investigated the relevant quenching mechanism of phosphor coatings used in white light devices based on UV LEDs. The final goal of the project was the design and fabrication of a high-efficacy white light UV-LED device through improved geometry and optimized phosphor coatings. At the end of the research period, which was extended to seamlessly carry over the research to a follow-up program, we have demonstrated a two-fold improvement in the conversion efficiency of a white light LED device, where the increase efficacy is due to both improved phosphor quantum efficiency and lamp geometry. Working prototypes have been displayed at DOE sponsored meetings and during the final presentation at the DOE Headquarters in Washington, DC. During the first phase of the project, a fundamental understanding of quenching processes in UV-LEDs was obtained, and the relationships that describe the performance of the phosphor as a function of photon flux, temperature, and phosphor composition were established. In the second phase of the project, these findings were then implemented to design the improved UV-LED lamp. In addition, our research provides a road map for the design of efficient white light LEDs, which will be an important asset during a follow-up project led by GE

Analysis of energy efficient highway lighting retrofits.

Science.gov (United States)

2015-06-01

Solid state lighting technology is advancing rapidly to a point where light emitting diode (LED) lighting : systems can be viable replacements for existing lighting systems using high pressure sodium (HPS). The : present report summarizes analyses co...

Improvement in light-extraction efficiency of light emitting diode ...

Indian Academy of Sciences (India)

The effect of various microlens parameters such as diameter and area fraction on light-extraction efficiency was systematically studied. Improvement of 4% in extraction efficiency was obtained by employing it on white light emitting diode. The area fraction of microlenses was increased up to 0.34 by reducing the spin speed.

Energy-saving control strategy for lighting system based on multivariate extremum seeking with Newton algorithm

International Nuclear Information System (INIS)

Yin, Chun; Dadras, Sara; Huang, Xuegang; Mei, Jun; Malek, Hadi; Cheng, Yuhua

2017-01-01

Highlights: • An energy-saving control strategy is proposed for multi-group lighting sources. • The proposed controller is designed to minimize the light-energy consumption. • It is designed to speed up the convergence rate without increasing the oscillation. • The minimal energy usage is guaranteed, while keeping the desired lighting level. • Experimental results shows the superiorities of the energy-saving control strategy. - Abstract: In recent years, the energy problem has been a universal concern. In order to improve the lighting energy efficiency and reduce the electric energy consumption, this paper develops an energy-saving control strategy for the lighting system with multiple lighting sources. The control strategy presented in this paper includes two parts: a new multivariate extremum seeking control method with Newton algorithm is developed to minimize the light-energy consumption by separately manipulating the brightness of multiple lighting sources, and a proportion-integration-differentiation control approach is adopted to realize the desired lighting level. The proposed scheme can increase the convergence speed of the closed loop system toward the minimum light-energy consumption, meanwhile, the accuracy of the control strategy will be improved. Experimental results illustrate that the light-energy consumption via the proposed method can reach more rapidly to a smaller vicinity of the minimum energy point, so, the lighting energy efficiency is greatly increased accordingly.

Energy - efficient buildings in pakistan

International Nuclear Information System (INIS)

Sohail, M.; Qureshi, M.U.D.

2011-01-01

Pakistan is one of the countries with the highest energy consumption for domestic use. Annual energy consumption by the domestic sector is 45.9 % of the total, while the industrial sector, consumes about 27.5%. About half of the total energy consumed is used in buildings and/or heating, ventilation and air-conditioning (HVAC) and lighting appliances. The energy consumed for the same purposes in China and UK is 25 to 30 % and 40 %, respectively, even in extreme weather conditions. Energy deficiency in Pakistan is approximately 5,000 MWe, which results in worst load-shedding in summers and, lately, even in winters. Building new energy sources like dams, coal power plants and renewable energy power projects are some possible solutions, but these are time taking and need at least 2 to 6 years to complete, depending upon the nature of the project. Fast development of energy-efficient buildings is, therefore, necessary to deal with exacerbating energy-crisis and related environmental impact in Pakistan. Innovations in the prevailing building-design will help the country in reducing the energy burden. These innovations may include improved architectural designs, energy-efficient building materials, electrical appliances and implementation of building energy-efficiency codes. In 1987, the National Energy Conservation Centre (ENERCON), was established under Ministry of Environment, Government of Pakistan, with the aim to build awareness among the masses for energy conservation, and to make policies regarding energy-conservation structures in the country. But no policy regarding building energy codes has been introduced by ENERCON till now. In collaboration with Pakistan Engineering Council (PEC), ENERCON has recently finalized the Building Energy Code of Pakistan Energy Provisions 2011 for which statutory notification is under process for necessary amendment in the building by-laws. The implementation of this Energy Code will result in 25 to 30 % of energy savings in the

US energy conservation and efficiency policies: Challenges and opportunities

International Nuclear Information System (INIS)

Dixon, Robert K.; McGowan, Elizabeth; Onysko, Ganna; Scheer, Richard M.

2010-01-01

Expanding energy conservation and efficiency in every sector nationwide is one of the most cost-effective instruments for reducing US energy imports, the trade deficit and energy's environmental impacts. For these reasons, energy conservation and efficiency have been essential elements of US energy policy since the oil embargos and price spikes of the 1970s. The Energy Independence and Security Act of 2007 (EISA) is the latest federal legislation to expand and strengthen US energy conservation and efficiency policies, programs, and practices. Specifically, EISA and its recent predecessor, the Energy Policy Act of 2005 (EPAct05), contain almost 200 titles with new provisions for energy conservation and efficiency aimed at improvements in vehicle fuel economy. These provisions include efficiency of appliances and lighting; energy savings in residential, commercial, and government buildings; the efficiency of industrial manufacturing plants; and the efficiency of electric power delivery and end-use. These actions have begun to contribute to new federal, state, and local policies, programs, and practices across the US, and expectations are high for increases in the level of energy savings. This paper summarizes the history of US energy conservation and efficiency policies, outlines EISA's and EPAct05's key provisions, and considers prospects for the future.

US energy conservation and efficiency policies. Challenges and opportunities

Energy Technology Data Exchange (ETDEWEB)

Dixon, Robert K.; Onysko, Ganna [Global Environment Facility, Climate Change and Chemicals, 1818 H Street, NW, MSN G6-602, Washington, DC 20433 (United States); McGowan, Elizabeth; Scheer, Richard M. [Energetics Incorporated, 7067 Columbia Gateway Drive, Suite 200, Columbia, MD 21046 (United States)

2010-11-15

Expanding energy conservation and efficiency in every sector nationwide is one of the most cost-effective instruments for reducing US energy imports, the trade deficit and energy's environmental impacts. For these reasons, energy conservation and efficiency have been essential elements of US energy policy since the oil embargos and price spikes of the 1970s. The Energy Independence and Security Act of 2007 (EISA) is the latest federal legislation to expand and strengthen US energy conservation and efficiency policies, programs, and practices. Specifically, EISA and its recent predecessor, the Energy Policy Act of 2005 (EPAct05), contain almost 200 titles with new provisions for energy conservation and efficiency aimed at improvements in vehicle fuel economy. These provisions include efficiency of appliances and lighting; energy savings in residential, commercial, and government buildings; the efficiency of industrial manufacturing plants; and the efficiency of electric power delivery and end-use. These actions have begun to contribute to new federal, state, and local policies, programs, and practices across the US, and expectations are high for increases in the level of energy savings. This paper summarizes the history of US energy conservation and efficiency policies, outlines EISA's and EPAct05's key provisions, and considers prospects for the future. (author)

US energy conservation and efficiency policies: Challenges and opportunities

Energy Technology Data Exchange (ETDEWEB)

Dixon, Robert K. [Global Environment Facility, Climate Change and Chemicals, 1818 H Street, NW, MSN G6-602, Washington, DC 20433 (United States); McGowan, Elizabeth [Energetics Incorporated, 7067 Columbia Gateway Drive, Suite 200, Columbia, MD 21046 (United States); Onysko, Ganna, E-mail: gonysko@thegef.or [Global Environment Facility, Climate Change and Chemicals, 1818 H Street, NW, MSN G6-602, Washington, DC 20433 (United States); Scheer, Richard M. [Energetics Incorporated, 7067 Columbia Gateway Drive, Suite 200, Columbia, MD 21046 (United States)

2010-11-15

Expanding energy conservation and efficiency in every sector nationwide is one of the most cost-effective instruments for reducing US energy imports, the trade deficit and energy's environmental impacts. For these reasons, energy conservation and efficiency have been essential elements of US energy policy since the oil embargos and price spikes of the 1970s. The Energy Independence and Security Act of 2007 (EISA) is the latest federal legislation to expand and strengthen US energy conservation and efficiency policies, programs, and practices. Specifically, EISA and its recent predecessor, the Energy Policy Act of 2005 (EPAct05), contain almost 200 titles with new provisions for energy conservation and efficiency aimed at improvements in vehicle fuel economy. These provisions include efficiency of appliances and lighting; energy savings in residential, commercial, and government buildings; the efficiency of industrial manufacturing plants; and the efficiency of electric power delivery and end-use. These actions have begun to contribute to new federal, state, and local policies, programs, and practices across the US, and expectations are high for increases in the level of energy savings. This paper summarizes the history of US energy conservation and efficiency policies, outlines EISA's and EPAct05's key provisions, and considers prospects for the future.

Energy transfer in light-adapted photosynthetic membranes: from active to saturated photosynthesis.

Science.gov (United States)

Fassioli, Francesca; Olaya-Castro, Alexandra; Scheuring, Simon; Sturgis, James N; Johnson, Neil F

2009-11-04

In bacterial photosynthesis light-harvesting complexes, LH2 and LH1 absorb sunlight energy and deliver it to reaction centers (RCs) with extraordinarily high efficiency. Submolecular resolution images have revealed that both the LH2:LH1 ratio, and the architecture of the photosynthetic membrane itself, adapt to light intensity. We investigate the functional implications of structural adaptations in the energy transfer performance in natural in vivo low- and high-light-adapted membrane architectures of Rhodospirillum photometricum. A model is presented to describe excitation migration across the full range of light intensities that cover states from active photosynthesis, where all RCs are available for charge separation, to saturated photosynthesis where all RCs are unavailable. Our study outlines three key findings. First, there is a critical light-energy density, below which the low-light adapted membrane is more efficient at absorbing photons and generating a charge separation at RCs, than the high-light-adapted membrane. Second, connectivity of core complexes is similar in both membranes, suggesting that, despite different growth conditions, a preferred transfer pathway is through core-core contacts. Third, there may be minimal subareas on the membrane which, containing the same LH2:LH1 ratio, behave as minimal functional units as far as excitation transfer efficiency is concerned.

Documentation of and satisfaction with the service delivery process of electric powered scooters among adult users in different national contexts

DEFF Research Database (Denmark)

Sund, Terje; Iwarsson, Susanne; Andersen, Mette C

2013-01-01

-up design based on a consecutive inclusion of 50 Danish and 86 Norwegian adults as they were about to be provided a scooter. A study-specific structured questionnaire for documentation of the SDP was administered. The Satisfaction with Assistive Technology Services was used for documenting user satisfaction...

Political ideology affects energy-efficiency attitudes and choices.

Science.gov (United States)

Gromet, Dena M; Kunreuther, Howard; Larrick, Richard P

2013-06-04

This research demonstrates how promoting the environment can negatively affect adoption of energy efficiency in the United States because of the political polarization surrounding environmental issues. Study 1 demonstrated that more politically conservative individuals were less in favor of investment in energy-efficient technology than were those who were more politically liberal. This finding was driven primarily by the lessened psychological value that more conservative individuals placed on reducing carbon emissions. Study 2 showed that this difference has consequences: In a real-choice context, more conservative individuals were less likely to purchase a more expensive energy-efficient light bulb when it was labeled with an environmental message than when it was unlabeled. These results highlight the importance of taking into account psychological value-based considerations in the individual adoption of energy-efficient technology in the United States and beyond.

Political ideology affects energy-efficiency attitudes and choices

Science.gov (United States)

Gromet, Dena M.; Kunreuther, Howard; Larrick, Richard P.

2013-01-01

This research demonstrates how promoting the environment can negatively affect adoption of energy efficiency in the United States because of the political polarization surrounding environmental issues. Study 1 demonstrated that more politically conservative individuals were less in favor of investment in energy-efficient technology than were those who were more politically liberal. This finding was driven primarily by the lessened psychological value that more conservative individuals placed on reducing carbon emissions. Study 2 showed that this difference has consequences: In a real-choice context, more conservative individuals were less likely to purchase a more expensive energy-efficient light bulb when it was labeled with an environmental message than when it was unlabeled. These results highlight the importance of taking into account psychological value-based considerations in the individual adoption of energy-efficient technology in the United States and beyond. PMID:23630266

Lower extremity ulceration caused by medical scooter injury: a case series.

Science.gov (United States)

Paparone, Pamela

2013-01-01

The motorized mobility scooter (MMS) provides considerable benefits to patients with mobility limitations. Nevertheless, safety concerns related to MMS use are an issue. With increased use because of increased life expectancy and chronic illness, there are a growing number of reports of MMS-related injuries, ranging from lacerations and contusions to fatalities. Comorbidities may also exacerbate wound care. Prevention of these injuries is greatly needed. The author presents 5 patients with lower-extremity ulceration caused by MMS injuries. To prevent these injuries, health care providers must carefully evaluate and monitor patients. Clinicians and MMS manufacturers also need to educate and train patients on the safe use of MMS devices, including the regular use of footwear. Copyright © 2013 Mosby, Inc. All rights reserved.

The fine tuning of carotenoid–chlorophyll interactions in light-harvesting complexes: an important requisite to guarantee efficient photoprotection via triplet–triplet energy transfer in the complex balance of the energy transfer processes

International Nuclear Information System (INIS)

Di Valentin, Marilena; Carbonera, Donatella

2017-01-01

Triplet–triplet energy transfer (TTET) from the chlorophyll to the carotenoid triplet state is the process exploited by photosynthetic systems to protect themselves from singlet oxygen formation under light-stress conditions. A deep comprehension of the molecular strategies adopted to guarantee TTET efficiency, while at the same time maintaining minimal energy loss and efficient light-harvesting capability, is still lacking. The paramagnetic nature of the triplet state makes electron paramagnetic resonance (EPR) the method of choice when investigating TTET. In this review, we focus on our extended comparative study of two photosynthetic antenna complexes, the Peridinin–chlorophyll a -protein of dinoflagellates and the light-harvesting complex II of higher plants, in order to point out important aspects of the molecular design adopted in the photoprotection strategy. We have demonstrated that a proper analysis of the EPR data allows one to identify the pigments involved in TTET and, consequently, gain an insight into the structure of the photoprotective sites. The structural information has been complemented by a detailed description of the electronic structure provided by hyperfine spectroscopy. All these elements represent the fundamental building blocks toward a deeper understanding of the requirements for efficient photoprotection, which is fundamental to guarantee the prolonged energy conversion action of photosynthesis. (topical review)

Energy efficiency

International Nuclear Information System (INIS)

2010-01-01

After a speech of the CEA's (Commissariat a l'Energie Atomique) general administrator about energy efficiency as a first rank challenge for the planet and for France, this publications proposes several contributions: a discussion of the efficiency of nuclear energy, an economic analysis of R and D's value in the field of fourth generation fast reactors, discussions about biofuels and the relationship between energy efficiency and economic competitiveness, and a discussion about solar photovoltaic efficiency

Highly efficient deep-blue organic light emitting diode with a carbazole based fluorescent emitter

Science.gov (United States)

Sahoo, Snehasis; Dubey, Deepak Kumar; Singh, Meenu; Joseph, Vellaichamy; Thomas, K. R. Justin; Jou, Jwo-Huei

2018-04-01

High efficiency deep-blue emission is essential to realize energy-saving, high-quality display and lighting applications. We demonstrate here a deep-blue organic light emitting diode using a novel carbazole based fluorescent emitter 7-[4-(diphenylamino)phenyl]-9-(2-ethylhexyl)-9H-carbazole-2-carbonitrile (JV234). The solution processed resultant device shows a maximum luminance above 1,750 cd m-2 and CIE coordinates (0.15,0.06) with a 1.3 lm W-1 power efficiency, 2.0 cd A-1 current efficiency, and 4.1% external quantum efficiency at 100 cd m-2. The resulting deep-blue emission enables a greater than 100% color saturation. The high efficiency may be attributed to the effective host-to-guest energy transfer, suitable device architecture facilitating balanced carrier injection and low doping concentration preventing efficiency roll-off caused by concentration quenching.

The cost and performance of utility commercial lighting programs. A report from the Database on Energy Efficiency Programs (DEEP) project

Energy Technology Data Exchange (ETDEWEB)

Eto, J.; Vine, E.; Shown, L.; Sonnenblick, R.; Payne, C. [Lawrence Berkeley Lab., CA (United States). Energy and Environment Div.

1994-05-01

The objective of the Database on Energy Efficiency Programs (DEEP) is to document the measured cost and performance of utility-sponsored, energy-efficiency, demand-side management (DSM) programs. Consistent documentation of DSM programs is a challenging goal because of problems with data consistency, evaluation methodologies, and data reporting formats that continue to limit the usefulness and comparability of individual program results. This first DEEP report investigates the results of 20 recent commercial lighting DSM programs. The report, unlike previous reports of its kind, compares the DSM definitions and methodologies that each utility uses to compute costs and energy savings and then makes adjustments to standardize reported program results. All 20 programs were judged cost-effective when compared to avoided costs in their local areas. At an average cost of 3.9{cents}/kWh, however, utility-sponsored energy efficiency programs are not ``too cheap to meter.`` While it is generally agreed upon that utilities must take active measures to minimize the costs and rate impacts of DSM programs, the authors believe that these activities will be facilitated by industry adoption of standard definitions and reporting formats, so that the best program designs can be readily identified and adopted.

Slow-light-enhanced energy efficiency for graphene microheaters on silicon photonic crystal waveguides

DEFF Research Database (Denmark)

Yan, Siqi; Zhu, Xiaolong; Frandsen, Lars Hagedorn

2017-01-01

Slow light has been widely utilized to obtain enhanced nonlinearities, enhanced spontaneous emissions and increased phase shifts owing to its ability to promote light-matter interactions. By incorporating a graphene on a slow-light silicon photonic crystal waveguide, here we experimentally...... in silicon photonics. The corresponding figure of merit of the device is 2.543 nW s, one order of magnitude better than results reported in previous studies. The influence of the length and shape of the graphene heater to the tuning efficiency is further investigated, providing valuable guidelines...

BC Hydro best practices : energy efficiency and integrated planning

International Nuclear Information System (INIS)

Henriques, D.

2004-01-01

The key elements to success in energy efficiency include integrated energy planning, a review of conservation potential, pursuing a target, risk sharing between all parties, and long term planning when making investments in demand side management (DSM). The barriers to cost effective energy efficiency investment were also outlined along with the scope of the conservation potential review which included 95 per cent of electricity end use applications in all market sectors including residential, commercial, institutional and industrial. BC Hydro's Power Smart program focuses on energy efficiency and load displacement to meet 35 per cent of the utility's forecasted growth by 2012. The sources of savings within each of the market sectors were identified. Key recommendations regarding energy efficiency and conservation were also presented with reference to financial incentives offered by BC Hydro to consumers to encourage a switch to more efficient lighting systems. 10 figs

Promoting energy efficiency in developing countries: The role of NGOs

International Nuclear Information System (INIS)

Wojtaszek, E.I.

1993-06-01

Developing countries need energy growth to spur economic growth. Yet energy activities contribute significantly to local water pollution and global greenhouse gas emissions. Energy efficiency offers the means to achieve the twin goals of sustainable economic/social development and environmental protection. Energy efficiency increases industrial competitiveness and frees up capital so it can be applied to other uses, such as health and education. The key to improving energy efficiency in developing countries will be acquiring and applying Western technologies, practices, and policies and building national institutions for promoting energy efficiency. Relevant energy-efficient technologies include the use of better electric motors, adjustable speed controls, combined cycle power cogeneration, improved lighting, better refrigeration technologies, and improved electric power transmission and distribution systems. Western countries can best help developing countries by providing guidance and resources to support nongovernmental organizations (NGOS) staffed by local experts; these institutions can capture the energy efficiency potential and ensure environmental protection in developing countries

The Waldo County project: A partnership for energy efficient economic development

International Nuclear Information System (INIS)

Baston, D.C.

1990-01-01

In April 1988, the state of Maine designated four economically disadvantaged areas as Job Opportunity Zones. An interministerial initiative was put into place to improve the economic situation of these regions and to attract high quality jobs. One of these, Waldo County, formed part of the service territory of Central Maine Power. In May 1988, that utility asked the Alliance to Save Energy to recommend means for aligning its energy efficiency program with the state's economic improvement program in order to bring about effective economic growth in Waldo County. The utility is in the process of adopting all of the energy efficiency measures recommended by the Alliance. The utility's program in this respect is focused on support for existing small businesses in the county. In most of these businesses, the largest component of their electric bill is for lighting. A pilot program to retrofit modern energy-efficient lighting will install state-of-the-art equipment such as electronic ballasts and compact fluorescents without cost to the customer. This program will provide substantial savings to existing businesses and provide efficiency savings to the utility. Marketing of commercial and residential energy management programs is also being intensified. Energy management assistance is also given to new businesses; this assistance includes financial incentives to install energy efficient equipment

Energy conservation, energy efficiency and energy savings regulatory hypotheses - taxation, subsidies and underlying economics

Energy Technology Data Exchange (ETDEWEB)

Trumpy, T. [International Legal Counsel, Brussels (Belgium)

1995-12-01

More efficient use of energy resources can be promoted by various regulatory means, i.e., taxation, subsidies, and pricing. Various incentives can be provided by income and revenue tax breaks-deductible energy audit fees, energy saving investment credits, breaks for energy saving entrepreneurs, and energy savings accounts run through utility accounts. Value added and excise taxes can also be adjusted to reward energy saving investments and energy saving entrepreneurial activity. Incentives can be provided in the form of cash refunds, including trade-in-and-scrap programs and reimbursements or subsidies on audit costs and liability insurance. Pricing incentives include lower rates for less energy use, prepayment of deposit related to peak load use, electronically dispatched multiple tariffs, savings credits based on prior peak use, and subsidized {open_quotes}leasing{close_quotes} of more efficient appliances and lights. Credits, with an emphasis on pooling small loans, and 5-year energy savings contracts are also discussed.

Adjusted light and dark cycles can optimize photosynthetic efficiency in algae growing in photobioreactors.

Directory of Open Access Journals (Sweden)

Eleonora Sforza

Full Text Available Biofuels from algae are highly interesting as renewable energy sources to replace, at least partially, fossil fuels, but great research efforts are still needed to optimize growth parameters to develop competitive large-scale cultivation systems. One factor with a seminal influence on productivity is light availability. Light energy fully supports algal growth, but it leads to oxidative stress if illumination is in excess. In this work, the influence of light intensity on the growth and lipid productivity of Nannochloropsis salina was investigated in a flat-bed photobioreactor designed to minimize cells self-shading. The influence of various light intensities was studied with both continuous illumination and alternation of light and dark cycles at various frequencies, which mimic illumination variations in a photobioreactor due to mixing. Results show that Nannochloropsis can efficiently exploit even very intense light, provided that dark cycles occur to allow for re-oxidation of the electron transporters of the photosynthetic apparatus. If alternation of light and dark is not optimal, algae undergo radiation damage and photosynthetic productivity is greatly reduced. Our results demonstrate that, in a photobioreactor for the cultivation of algae, optimizing mixing is essential in order to ensure that the algae exploit light energy efficiently.

Efficient light emitting devices based on phosphorescent partially doped emissive layers

KAUST Repository

Yang, Xiaohui; Jabbour, Ghassan E.

2013-01-01

We report efficient organic light emitting devices employing an ultrathin phosphor emissive layer. The electroluminescent spectra of these devices can be tuned by introducing a low-energy emitting phosphor layer into the emission zone. Devices

Environmental friendly high efficient light source. Plasma lamp. 2006 annual report

Energy Technology Data Exchange (ETDEWEB)

Courret, G.

2006-07-01

This annual report for 2006 for the Swiss Federal Office of Energy (SFOE) reports on work being done on the development of a high-efficiency source of light based on the light emission of a plasma. The report presents a review of work done in 2006, including thermodynamics and assessment of the efficiency of the magnetron, tests with small bulbs, study of the standing wave ratio (microwave fluxes) and the development of a new coupling system to allow ignition in very small bulbs. Also, knowledge on the fillings of the bulb and induced effects of the modulator were gained. The development of a second generation of modulator to obtain higher efficiency at lower power is noted.

Lighting Energy Saving with Light Pipe in Farm Animal Production

Directory of Open Access Journals (Sweden)

Hans von Wachenfelt

2015-12-01

Full Text Available The Swedish animal production sector has potential for saving electric lighting of €4-9 million per year using efficient daylight utilisation. To demonstrate this, two light pipe systems, Velux® (house 1 and Solatube® (house 2, are installed in two identical pig houses to determine if the required light intensity, daylight autonomy (DA, and reduced electricity use for illumination can be achieved. In each house, three light sensors continuously measure the indoor daylight relative to an outdoor sensor. If the horizontal illuminance at pig height decreases below 40 lux between 08.00 and 16.00 hours, an automatic control system activates the lights, and electricity use is measured. The daylight factor (DF and DA are determined for each house, based on annual climate data. The mean annual DA of 48% and 55% is achieved for house 1 and house 2, respectively. Light pipes in house 2 have delivered significantly more DA than those in house 1. The most common illuminance range between 0 and 160 lux is recorded in both houses, corresponding to approximately 82% and 83% of daylight time for house 1 and house 2, respectively. Further, the daylighting system for house 2 has produced a uniform DF distribution between 0.05 and 0.59. The results demonstrate that considerable electric energy savings can be achieved in the animal production sector using light pipes. Saving 50% of electric lighting would correspond to 36 GWh or 2520 t CO2 per year for Sweden, but currently the energy savings are not making the investment profitable.

Light ion beam approach to ICF ignition, gain, and energy production

International Nuclear Information System (INIS)

Olson, R.; Allshouse, G.; Cook, D.

1993-01-01

The US Department of Energy is supporting research oriented toward both near-term defense applications as well as long-term energy applications of inertial confinement fusion (ICF). The ICF programs at Sandia National Laboratories (SNL) is directed toward validating light ions as an efficient driver for these applications. The light ion laboratory microfusion facility (LMF) is envisioned as a facility in which high gain ICF targets could be developed and utilized in defense-related experiments. The LIBRA light ion beam commercial reactor study provides a baseline approach towards the use of the high gain light ion ICF technology as a source of commercial electrical energy

Light ion beam approach to ICF ignition, gain, and energy production

International Nuclear Information System (INIS)

Olson, R.; Allshouse, G.; Cook, D.

1994-01-01

The U.S. Department of Energy is supporting research oriented toward both near-term defense applications as well as long-term energy applications of inertial confinement fusion (ICF). The ICF program at Sandia National Laboratories (SNL) is directed toward validating light ions as an efficient driver for these applications. The light ion laboratory microfusion facility (LMF) is envisioned as a facility in which high gain ICF targets could be developed and utilized in defense-related experiments. The LIBRA light ion beam commercial reactor study provides a baseline approach towards the use of the high gain light ion ICF technology as a source of commercial electrical energy. (author)

White Paper on Energy Efficiency Status of Energy-Using Products in China (2011)

Energy Technology Data Exchange (ETDEWEB)

Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Romankiewicz, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-06-01

This White Paper focuses on the areas and products involved in the above tasks, based on the White Paper - Energy Efficiency Status of Energy-Using Products in China (2010), here referred to as “White Paper 2010”, which analyzed the energy efficiency status of 21 typical energy-using products in five sectors: household appliances, office equipment, commercial equipment, industrial equipment, and lighting equipment. Table 1 illustrates the detailed product coverage for this year’s paper, noting the addition of three household appliance items (automatic electric rice cooker, AC electric fan, and household induction cooktop) and one industrial sector item (three-phase distribution transformer).

Efficient light emitting devices based on phosphorescent partially doped emissive layers

KAUST Repository

Yang, Xiaohui

2013-05-29

We report efficient organic light emitting devices employing an ultrathin phosphor emissive layer. The electroluminescent spectra of these devices can be tuned by introducing a low-energy emitting phosphor layer into the emission zone. Devices with the emissive layer consisting of multiple platinum-complex/spacer layer cells show a peak external quantum efficiency of 18.1%, which is among the best EQE values for platinum-complex based light emitting devices. Devices with an ultrathin phosphor emissive layer show stronger luminance decay with the operating time compared to the counterpart devices having a host-guest emissive layer.

Essays on the efficient integration of renewable energies into electricity markets

Energy Technology Data Exchange (ETDEWEB)

Obermueller, Frank

2018-01-09

The dissertation ''Essay on the Efficient Integration of Renewable Energies into Electricity Markets'' consists of five research articles which shed light on the efficient integration of renewable energies into electricity markets. A major share of renewable energies has characteristics which differ from classical conventional generation technologies. The uncertain weather-dependent characteristics in combination with almost-zero marginal generation costs raise new challenges to some parts of the electricity system. On the other side, the promotion of renewable energies seems promising to achieve the Energy Transition targets and reduce Germany's CO{sub 2}-emissions. This becomes relevant in the light of the 2015 UN Climate Change Conference which negotiated the Paris Agreement to tackle climate change, e.g. by the restriction of global warming to a maximum of 2 C, and translate to CO{sub 2}-reduction efforts, especially for the carbon-dioxide intense electricity sectors. The five research papers focusing on different aspects and potential inefficiencies of the renewable energy market integration. The focus can roughly be separated into temporal and regional efficiency examinations. The temporal efficiency is subject to paper 1, paper 2 and paper 3. The regional efficiency is subject to paper 5 which is based on the preliminary findings and the generated dataset in paper 4.

Essays on the efficient integration of renewable energies into electricity markets

International Nuclear Information System (INIS)

Obermueller, Frank

2018-01-01

The dissertation ''Essay on the Efficient Integration of Renewable Energies into Electricity Markets'' consists of five research articles which shed light on the efficient integration of renewable energies into electricity markets. A major share of renewable energies has characteristics which differ from classical conventional generation technologies. The uncertain weather-dependent characteristics in combination with almost-zero marginal generation costs raise new challenges to some parts of the electricity system. On the other side, the promotion of renewable energies seems promising to achieve the Energy Transition targets and reduce Germany's CO 2 -emissions. This becomes relevant in the light of the 2015 UN Climate Change Conference which negotiated the Paris Agreement to tackle climate change, e.g. by the restriction of global warming to a maximum of 2 C, and translate to CO 2 -reduction efforts, especially for the carbon-dioxide intense electricity sectors. The five research papers focusing on different aspects and potential inefficiencies of the renewable energy market integration. The focus can roughly be separated into temporal and regional efficiency examinations. The temporal efficiency is subject to paper 1, paper 2 and paper 3. The regional efficiency is subject to paper 5 which is based on the preliminary findings and the generated dataset in paper 4.

A Hybrid Indoor Ambient Light and Vibration Energy Harvester for Wireless Sensor Nodes

Directory of Open Access Journals (Sweden)

Hua Yu

2014-05-01

Full Text Available To take advantage of applications where both light and vibration energy are available, a hybrid indoor ambient light and vibration energy harvesting scheme is proposed in this paper. This scheme uses only one power conditioning circuit to condition the combined output power harvested from both energy sources so as to reduce the power dissipation. In order to more accurately predict the instantaneous power harvested from the solar panel, an improved five-parameter model for small-scale solar panel applying in low light illumination is presented. The output voltage is increased by using the MEMS piezoelectric cantilever arrays architecture. It overcomes the disadvantage of traditional MEMS vibration energy harvester with low voltage output. The implementation of the maximum power point tracking (MPPT for indoor ambient light is implemented using analog discrete components, which improves the whole harvester efficiency significantly compared to the digital signal processor. The output power of the vibration energy harvester is improved by using the impedance matching technique. An efficient mechanism of energy accumulation and bleed-off is also discussed. Experiment results obtained from an amorphous-silicon (a-Si solar panel of 4.8 × 2.0 cm2 and a fabricated piezoelectric MEMS generator of 11 × 12.4 mm2 show that the hybrid energy harvester achieves a maximum efficiency around 76.7%.

Energy-saving quality road lighting with colloidal quantum dot nanophosphors

Science.gov (United States)

Erdem, Talha; Kelestemur, Yusuf; Soran-Erdem, Zeliha; Ji, Yun; Demir, Hilmi Volkan

2014-12-01

Here the first photometric study of road-lighting white light-emitting diodes (WLEDs) integrated with semiconductor colloidal quantum dots (QDs) is reported enabling higher luminance than conventional light sources, specifically in mesopic vision regimes essential to street lighting. Investigating over 100 million designs uncovers that quality road-lighting QD-WLEDs, with a color quality scale and color rendering index ≥85, enables 13-35% higher mesopic luminance than the sources commonly used in street lighting. Furthermore, these QD-WLEDs were shown to be electrically more efficient than conventional sources with power conversion efficiencies ≥16-29%. Considering this fact, an experimental proof-of-concept QD-WLED was demonstrated, which is the first account of QD based color conversion custom designed for street lighting applications. The obtained white LED achieved the targeted mesopic luminance levels in accordance with the road lighting standards of the USA and the UK. These results indicate that road-lighting QD-WLEDs are strongly promising for energy-saving quality road lighting.

Energy Efficiency Adult Tracking Report - Final

Energy Technology Data Exchange (ETDEWEB)

Gibson-Grant, Amy [Ad Council, NY (United States)

2014-09-30

Postwave tracking study for the Energy Efficiency Adult Campaign This study serves as measure of key metrics among the campaign’s target audience, homeowners age 25+. Key measures include: Awareness of messages relating to the broad issue; Recognition of the PSAs; Relevant attitudes, including interest, ease of taking energy efficient steps, and likelihood to act; Relevant knowledge, including knowledge of light bulb alternatives and energy efficient options; and Relevant behaviors, including specific energy-saving behaviors mentioned within the PSAs. Wave 1: May 27 – June 7, 2011 Wave 2: May 29 – June 8, 2012 Wave 3: May 29 – June 19, 2014 General market sample of adults 25+ who own their homes W1 sample: n = 704; W2: n=701; W3: n=806 Online Survey Panel Methodology Study was fielded by Lightspeed Research among their survey panel. Sample is US Census representative of US homeowners by race/ethnicity, income, age, region, and family status. At least 30% of respondents were required to have not updated major appliances in their home in the past 5 years (dishwasher, stove, refrigerator, washer, or dryer).

Energy-efficiency based classification of the manufacturing workstation

Science.gov (United States)

Frumuşanu, G.; Afteni, C.; Badea, N.; Epureanu, A.

2017-08-01

EU Directive 92/75/EC established for the first time an energy consumption labelling scheme, further implemented by several other directives. As consequence, nowadays many products (e.g. home appliances, tyres, light bulbs, houses) have an EU Energy Label when offered for sale or rent. Several energy consumption models of manufacturing equipments have been also developed. This paper proposes an energy efficiency - based classification of the manufacturing workstation, aiming to characterize its energetic behaviour. The concept of energy efficiency of the manufacturing workstation is defined. On this base, a classification methodology has been developed. It refers to specific criteria and their evaluation modalities, together to the definition & delimitation of energy efficiency classes. The energy class position is defined after the amount of energy needed by the workstation in the middle point of its operating domain, while its extension is determined by the value of the first coefficient from the Taylor series that approximates the dependence between the energy consume and the chosen parameter of the working regime. The main domain of interest for this classification looks to be the optimization of the manufacturing activities planning and programming. A case-study regarding an actual lathe classification from energy efficiency point of view, based on two different approaches (analytical and numerical) is also included.

Energy Efficiency Plan 2009-2012; Energie Efficiency Plan 2009-2012

Energy Technology Data Exchange (ETDEWEB)

Meulen, M.M.W. (ed.)

2009-02-15

The aim of the Energy Efficiency Plan is to give an overview of the energy conservation plans of the Eindhoven University of Technology in Eindhoven, Netherlands, which must result in efficient use of energy conform the long-range agreements between businesses, industry and organizations and the Dutch government to improve energy efficiency (MJA3) [Dutch] Het doel van het EEP (Energie Efficiency Plan) is het in beeld brengen van de energiebesparingsplannen die leiden tot een efficienter gebruik van energie conform de MJA-3 afspraak (de derde Meerjaren Afspraak)

Manipulation of Thermally Activated Delayed Fluorescence of Blue Exciplex Emission: Fully Utilizing Exciton Energy for Highly Efficient Organic Light Emitting Diodes with Low Roll-Off.

Science.gov (United States)

Wang, Zixing; Wang, Hedan; Zhu, Jun; Wu, Peng; Shen, Bowen; Dou, Dehai; Wei, Bin

2017-06-28

The application of exciplex energy has become a unique way to achieve organic light-emitting diodes (OLEDs) with high efficiencies, low turn-on voltage, and low roll-off. Novel δ-carboline derivatives with high triplet energy (T 1 ≈ 2.92 eV) and high glass transition temperature (T g ≈ 153 °C) were employed to manipulate exciplex emissions in this paper. Deep blue (peak at 436 nm) and pure blue (peak at 468 nm) thermally activated delayed fluorescence (TADF) of exciplex OLEDs were demonstrated by utilizing them as emitters with the maximum current efficiency (CE) of 4.64 cd A -1 , power efficiency (PE) of 2.91 lm W -1 , and external quantum efficiency (EQE) of 2.36%. Highly efficient blue phosphorescent OLEDs doped with FIrpic showed a maximum CE of 55.6 cd A -1 , PE of 52.9 lm W -1 , and EQE of 24.6% respectively with very low turn on voltage at 2.7 V. The devices still remain high CE of 46.5 cd A -1 at 100 cd m -2 , 45.4 cd A -1 at 1000 cd m -2 and 42.3 cd A -1 at 5000 cd m -2 with EQE close to 20% indicating low roll-off. Manipulating blue exciplex emissions by chemical structure gives an ideal strategy to fully utilize all exciton energies for lighting of OLEDs.

The economic impacts of energy efficiency

International Nuclear Information System (INIS)

Jean, R.

1990-01-01

Hydro Quebec's energy efficiency initiatives are reviewed and the economic benefits it expects to garner from such programs are described. Energy efficiency programs affect the cost of supplying electricity, and rates usually rise during the early years and are subsequently offset by the benefits the program generates. Energy efficiency programs should allow Hydro Quebec to avoid $6 billion in expenditures for electricity supply, while entailing contributions of $1.4 billion for the efficiency measures. Evaluation of the potential for efficiency has allowed Hydro Quebec to set a target of 12.9 TWh/y in 1999 on a potential estimated at 18% of regular sales in Quebec in 1989, namely 23.3 TWh. Customers, who contribute $1.4 billion of their own funds to efficiency programs will realize savings of $3.2 billion. Hydro Quebec programs insist strongly on replacement of appliances and motors of all sorts, and in the residential sector, purchases of slightly less than $0.5 billion will consist of electric lamps (3%), water heaters (2.4%), insulation products (32%), hardware (2.5%), and various electric appliances (33%). In the commercial sector, expenditures will be higher, reaching ca $650 million. These are allocated to purchases of electric lamps (18%), heating equipment (12%), insulation products (24%), street lighting (4%), and various electric devices such as controls (39%). 2 figs., 4 tabs

Efficient utilization of energy in office buildings. Planning manual; Effiziente Energienutzung in Buerogebaeuden. Planungsleitfaden

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-15

Regarding to the energy efficiency of office buildings, a high standard is set to architects: Office buildings need more energy for the cooling in the summer than for the heating in the winter. Additionally, there is an energy consumption for lighting, ventilation and operation of office equipment. Under this aspect, in the planning manual under consideration ten demands for an efficient energy utilization at office buildings are described: (a) Integral concept for the minimization of the entire power demand; (b) Compact building method and very good structural thermal protection; (c) Adapted glass areas and quality of vitrifications; (d) Integrals ventilation planning; (e) Efficient ventilation systems; (f) Efficient room climate concept and minimization of internal and outside heat loads; (g) Utilization of daylight with adapted architectural draft; (h) Efficient artificial lighting; (i) Supply of warmth and coldness with minimum characteristic values for primary energy; (j) Energy monitoring and optimization of operation. This manual also is valid for other buildings such as schools, administration buildings or swimming pools.

Energy Efficiency Roadmap for Uganda, Making Energy Efficiency Count. Executive Summary

Energy Technology Data Exchange (ETDEWEB)

de la Rue du Can, Stephane; Pudleiner, David; Jones, David; Khan, Aleisha

2017-06-15

Like many countries in Sub-Saharan Africa, Uganda has focused its energy sector investments largely on increasing energy access by increasing energy supply. The links between energy efficiency and energy access, the importance of energy efficiency in new energy supply, and the multiple benefits of energy efficiency for the level and quality of energy available, have been largely overlooked. Implementing energy efficiency in parallel with expanding both the electricity grid and new clean energy generation reduces electricity demand and helps optimize the power supply so that it can serve more customers reliably at minimum cost. Ensuring efficient appliances are incorporated into energy access efforts provides improved energy services to customers. Energy efficiency is an important contributor to access to modern energy. This Energy Efficiency Roadmap for Uganda (Roadmap) is a response to the important role that electrical energy efficiency can play in meeting Uganda’s energy goals. Power Africa and the United Nations Sustainable Energy for All (SEforALL) initiatives collaborated with more than 24 stakeholders in Uganda to develop this document. The document estimates that if the most efficient technologies on the market were adopted, 2,224 gigawatt hours could be saved in 2030 across all sectors, representing 31% of the projected load. This translates into 341 megawatts of peak demand reductions, energy access to an additional 6 million rural customers and reduction of carbon dioxide emissions by 10.6 million tonnes in 2030. The Roadmap also finds that 91% of this technical potential is cost-effective, and 47% is achievable under conservative assumptions. The Roadmap prioritizes recommendations for implementing energy efficiency and maximizing benefits to meet the goals and priorities established in Uganda’s 2015 SEforALL Action Agenda. One important step is to create and increase demand for efficiency through long-term enabling policies and financial incentives

Progress Implementing the IEA 25 Energy Efficiency Policy Recommendations

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

Significantly improving energy efficiency remains a priority for all countries. Meetings of G8 leaders and IEA ministers reaffirmed the critical role that improved energy efficiency can play in addressing energy security, environmental and economic challenges. Many IEA publications have also documented the essential role of energy efficiency. For example, the World Energy Outlook and the Energy Technology Perspectives reports identify energy efficiency as the most significant contributor to achieving energy security, economic and environmental goals. Energy efficiency is clearly the “first fuel” in the delivery of energy services in the coming low-carbon energy future. To support governments in their implementation of energy efficiency, the IEA recommended the adoption of specific energy efficiency policy measures to the G8 summits in 2006, 2007 and 2008. The consolidated set of recommendations to these summits is known as the ‘IEA 25 energy efficiency policy recommendations’ because it covers 25 fields of action across seven priority areas: cross-sectoral activity, buildings, appliances, lighting, transport, industry and energy utilities. The IEA estimates that if implemented globally without delay, the proposed actions could save as much as 7.6 giga tonnes (Gt) CO2/year by 2030 – almost 1.5 times the current annual carbon dioxide (CO2) emissions of the United States. The IEA 25 energy efficiency policy recommendations were developed to address policy gaps and priorities. This has two implications. First, the recommendations do not cover the full range of energy efficiency policy activity possible. Rather, they focus on priority energy efficiency policies identified by IEA analysis. Second, while IEA analysis, the energy efficiency professional literature and engagement with experts clearly demonstrate the broad benefits of these IEA priority measures, the recommendations are not weighted to reflect the different energy end-use make up of different

Energy Optimization of Road Tunnel Lighting Systems

Directory of Open Access Journals (Sweden)

Ferdinando Salata

2015-07-01

Full Text Available A road tunnel is an enclosed and covered infrastructure for the vehicular traffic. Its lighting system provides 24 h of artificial sources only, with a higher amount of electric power used during the day. Due to safety reasons, when there is natural lighting outside the tunnel, the lighting levels in the stretches right after the entrance and before the exit must be high, in order to guide the driver’s eye towards the middle of the tunnel where the luminance must guarantee safe driving, avoid any over-dimensioning of the lighting systems, and produce energy savings. Such effects can be reached not only through the technological advances in the field of artificial lighting sources with high luminous efficiency, but also through new materials for road paving characterized by a higher reflection coefficient than other ordinary asphalts. This case study examines different technical scenarios, analyzing and comparing possible energy and economic savings. Traditional solutions are thus compared with scenarios suggesting the solutions previously mentioned. Special asphalts are interesting from an economic point of view, whereas the high costs of LED sources nowadays represent an obstacle for their implementation.

Influence of driving cycles on Euro 3 scooter emissions and fuel consumption

International Nuclear Information System (INIS)

Prati, Maria V.; Zamboni, Giorgio; Costagliola, Maria A.; Meccariello, Giovanni; Carraro, Chiara; Capobianco, Massimo

2011-01-01

Highlights: → Fuel consumption and emissions of Euro 3 scooters defined on different driving cycles. → Comparison of standard, real world driving cycles and measured urban speed patterns. → Statistical analysis of kinematic parameters to group driving cycle in clusters. → Clusters can explain pollutant and fuel consumption behaviour in hot conditions. → Cold start mixture enrichment strategy has a major influence on extra-emissions. - Abstract: Regulated pollutant emissions and fuel consumption were characterized at the exhaust of two Euro 3 4-stroke medium-size motorcycles during the execution of both standard and real world driving cycles. A principal component analysis was carried out to group in a cluster the driving cycles with similar kinematic parameters. Hot start results, analysed according to this cluster grouping, show that the main differences are explained by overall mean speed and high positive acceleration of driving cycles. Lower mean speeds produce higher CO 2 emission factors, while the influence on CO and HC is more complex. NO X are not significantly affected by the driving pattern. Inside the same cluster, the whole duration of the acceleration phases could discriminate emission behaviour. In-depth analysis of cold start results was conducted in order to assess the influence of the driving cycle and vehicle characteristics on cold start duration. Cold start extra emissions are more influenced by the duration of the enrichment phase than by the catalyst light-off. The larger number of accelerations occurring during real world driving cycles produces higher variability of air fuel ratio and hence higher cold start extra emissions.

On Energy Efficiency of Prioritized IoT Systems

KAUST Repository

Alabbasi, Abdulrahman; Shihada, Basem; Cavdar, Cicek

2018-01-01

The inevitable deployment of 5G and the Internet of Things (IoT) sheds the light on the importance of the energy efficiency (EE) performance of Device-to- Device (DD) communication systems. In this work, we address a potential IoT application, where

Basic Research Needs for Solid-State Lighting. Report of the Basic Energy Sciences Workshop on Solid-State Lighting, May 22-24, 2006

Energy Technology Data Exchange (ETDEWEB)

Phillips, J. M.; Burrows, P. E.; Davis, R. F.; Simmons, J. A.; Malliaras, G. G.; So, F.; Misewich, J.A.; Nurmikko, A. V.; Smith, D. L.; Tsao, J. Y.; Kung, H.; Crawford, M. H.; Coltrin, M. E.; Fitzsimmons, T. J.; Kini, A.; Ashton, C.; Herndon, B.; Kitts, S.; Shapard, L.; Brittenham, P. W.; Vittitow, M. P.

2006-05-24

The workshop participants enthusiastically concluded that the time is ripe for new fundamental science to beget a revolution in lighting technology. SSL sources based on organic and inorganic materials have reached a level of efficiency where it is possible to envision their use for general illumination. The research areas articulated in this report are targeted to enable disruptive advances in SSL performance and realization of this dream. Broad penetration of SSL technology into the mass lighting market, accompanied by vast savings in energy usage, requires nothing less. These new ?good ideas? will be represented not by light bulbs, but by an entirely new lighting technology for the 21st century and a bright, energy-efficient future indeed.

Approach to Low-Cost High-Efficiency OLED Lighting. Building Technologies Solid State Lighting (SSL) Program Final Report

Energy Technology Data Exchange (ETDEWEB)

Pei, Qibing [Univ. of California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering

2017-10-06

This project developed an integrated substrate which organic light emitting diode (OLED) panel developers could employ the integrated substrate to fabricate OLED devices with performance and projected cost meeting the MYPP targets of the Solid State Lighting Program of the Department of Energy. The project optimized the composition and processing conditions of the integrated substrate for OLED light extraction efficiency and overall performance. The process was further developed for scale up to a low-cost process and fabrication of prototype samples. The encapsulation of flexible OLEDs based on this integrated substrate was also investigated using commercial flexible barrier films.

Building energy efficiency in different climates

International Nuclear Information System (INIS)

Lam, Joseph C.; Wan, Kevin K.W.; Tsang, C.L.; Yang Liu

2008-01-01

Energy simulation was conducted for office buildings in the five major climate zones - severe cold, cold, hot summer and cold winter, mild, and hot summer and warm winter - in China using DOE-2.1E. The primary aim was to investigate the thermal and energy performance of office buildings with centralised heating, ventilation and air conditioning plants in the major climatic zones in China. The computed results were analysed in three aspects - heating load, cooling load and the corresponding building energy consumption. The building peak monthly heating load varied from 142 MW h (1033 MW h cooling) in Hong Kong to 447 MW h (832 MW h cooling) in Harbin. It was also found that passive solar designs could have large energy savings potential in the severe cold and cold climates. In Harbin, the window solar component helped lower the annual building heating load by 650 MW h. Internal loads (lighting and office equipment) and part load operations of fans and pumps also played a significant role in the overall building energy efficiency. This paper presents the work, its findings and energy efficiency implications

The health risks associated with energy efficient fluorescent, LEDs, and artificial lighting

Science.gov (United States)

Panahi, Allen

2014-09-01

With the phasing out of incandescent lamps in many countries, the introduction of new LED based light sources and luminaries sometimes raise the question of whether the spectral characteristics of the LED and other energy savings Fluorescent lights including the popular CFLs are suitable to replace the traditional incandescent lamps. These concerns are sometimes raised particularly for radiation emissions in the UV and Blue parts of the spectrum. This paper aims to address such concerns for the common `white light' sources typically used in household and other general lighting used in the work place. Recent studies have shown that women working the night shift have an increased probability of developing breast cancer. We like to report on the findings of many studies done by medical professionals, in particular the recent announcement of AMA in the US and many studies conducted in the UK, as well as the European community to increase public awareness on the long term health risks of the optical and opto-biological effects on the human health caused by artificial lighting.

Energy efficient home in Lebanon

International Nuclear Information System (INIS)

1997-01-01

The purpose of the study is to present new methods or new products that could save money while improving the environment in Lebanon. Cost of energy is on the increase and is predicted to increase even more in the future. Environmental issues and awareness are gaining momentum in Lebanon. With electricity production directly linked to power plants that represent about 30% of the air pollution which is also linked to health related issues. There is an intermediate need to introduce more energy efficient products in the construction industry which require less energy to operate or could be linked indirectly to energy. In this context, cost-benefit analysis of heating, light, painting, energy consumption and energy lamp burning hours in addition to fuel burner, gas and electric heater in buildings are presented in tables. Finally, there is a lack of awareness on the positive impact on the environment reflected in the saving of natural resources, reducing pollution and creation of a better living environment

Energy utilization of light and heavy weaned piglets subjected to different dietary energy levels

Directory of Open Access Journals (Sweden)

Andréa Machado Leal Ribeiro

Full Text Available ABSTRACT This study was conducted to evaluate the effects of dietary metabolisable energy (ME: 3.25, 3.40, 3.55, or 3.70 Mcal kg−1 and weaning weight (WW: light 4.0±0.7 kg, and heavy: 6.3±0.6 kg on productive response and energy utilization of weaned piglets. Sixty-four male piglets were housed in 32 metabolic cages (two animals per cage during the first 14 d postweaning. At day 15, only one animal per cage was kept until day 28. Body composition, energy, and nutrient deposition rates and energy utilization efficiency were measured through a comparative slaughter procedure. Piglets with light WW had a poorer feed conversion ratio and lower weight gain and feed intake when expressed per live weight. Increased ME led to greater daily fat deposition in the empty bodies (defined as weighted mean of the carcass + organs + blood, no intestinal content, while light WW piglets had a reduced protein deposition. Light WW piglets increased heat production with increased ME, but no effect was seen for the heavy WW piglets. By contrast, heavy WW piglets increased empty body gross energy as ME increased, while no influence was observed on light WW piglets. Increasing dietary energy levels did not contribute to the subsequent growth performance of piglets that were lighter at weaning. The lack of interaction between weaning weight and dietary ME content on growth performance does not support the hypothesis that light piglets at weaning do not exhibit compensatory growth because of limitations in energy intake.

Learning energy efficiency: experience curves for household appliances and space heating, cooling, and lighting technologies

NARCIS (Netherlands)

Weiss, M.; Junginger, H.M.; Patel, M.K.

2008-01-01

Improving demand side energy efficiency is an important strategy for establishing a sustainable energy system. Large potentials for energy efficiency improvements exist in the residential and commercial buildings sector. This sector currently accounts for almost 40% of the European Union’s (EU)

Carbon-doped SnS2 nanostructure as a high-efficiency solar fuel catalyst under visible light.

Science.gov (United States)

Shown, Indrajit; Samireddi, Satyanarayana; Chang, Yu-Chung; Putikam, Raghunath; Chang, Po-Han; Sabbah, Amr; Fu, Fang-Yu; Chen, Wei-Fu; Wu, Chih-I; Yu, Tsyr-Yan; Chung, Po-Wen; Lin, M C; Chen, Li-Chyong; Chen, Kuei-Hsien

2018-01-12

Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an L-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS 2 (SnS 2 -C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO 2 to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS 2 lattice, resulting in different photophysical properties as compared with undoped SnS 2 . This SnS 2 -C photocatalyst significantly enhances the CO 2 reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS 2 -C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO 2 reduction under visible light, where the in situ carbon-doped SnS 2 nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.

Spreading The Net: The Multiple Benefits Of Energy Efficiency Improvements

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

policy design. The paper also discusses the “rebound effect”, which can imply that energy efficiency measures produce less energy savings than expected, but should be reconsidered in light of the variety of other benefits which are generated.

Light quality and efficiency of consumer grade solid state lighting products

DEFF Research Database (Denmark)

Dam-Hansen, Carsten; Corell, Dennis Dan; Thorseth, Anders

2013-01-01

The rapid development in flux and efficiency of Light Emitting Diodes (LED) has resulted in a flooding of the lighting market with Solid State Lighting (SSL) products. Many traditional light sources can advantageously be replaced by SSL products. There are, however, large variations in the quality...... of these products, and some are not better than the ones they are supposed to replace. A lack of quality demands and standards makes it difficult for consumers to get an overview of the SSL products. Here the results of a two year study investigating SSL products on the Danish market are presented. Focus has been...... on SSL products for replacement of incandescent lamps and halogen spotlights. The warm white light and good color rendering properties of these traditional light sources are a must for lighting in Denmark and the Nordic countries. 266 SSL replacement lamps have been tested for efficiency and light...

Highly efficient energy transfer from a carbonyl carotenoid to chlorophyll a in the main light harvesting complex of Chromera velia.

Science.gov (United States)

Durchan, Milan; Keşan, Gürkan; Slouf, Václav; Fuciman, Marcel; Staleva, Hristina; Tichý, Josef; Litvín, Radek; Bína, David; Vácha, František; Polívka, Tomáš

2014-10-01

We report on energy transfer pathways in the main light-harvesting complex of photosynthetic relative of apicomplexan parasites, Chromera velia. This complex, denoted CLH, belongs to the family of FCP proteins and contains chlorophyll (Chl) a, violaxanthin, and the so far unidentified carbonyl carotenoid related to isofucoxanthin. The overall carotenoid-to-Chl-a energy transfer exhibits efficiency over 90% which is the largest among the FCP-like proteins studied so far. Three spectroscopically different isofucoxanthin-like molecules were identified in CLH, each having slightly different energy transfer efficiency that increases from isofucoxanthin-like molecules absorbing in the blue part of the spectrum to those absorbing in the reddest part of spectrum. Part of the energy transfer from carotenoids proceeds via the ultrafast S2 channel of both the violaxanthin and isofucoxanthin-like carotenoid, but major energy transfer pathway proceeds via the S1/ICT state of the isofucoxanthin-like carotenoid. Two S1/ICT-mediated channels characterized by time constants of ~0.5 and ~4ps were found. For the isofucoxanthin-like carotenoid excited at 480nm the slower channel dominates, while those excited at 540nm employs predominantly the fast 0.5ps channel. Comparing these data with the excited-state properties of the isofucoxanthin-like carotenoid in solution we conclude that, contrary to other members of the FCP family employing carbonyl carotenoids, CLH complex suppresses the charge transfer character of the S1/ICT state of the isofucoxanthin-like carotenoid to achieve the high carotenoid-to-Chl-a energy transfer efficiency. Copyright © 2014 Elsevier B.V. All rights reserved.

Focusing of light energy inside a scattering medium by controlling the time-gated multiple light scattering

Science.gov (United States)

Jeong, Seungwon; Lee, Ye-Ryoung; Choi, Wonjun; Kang, Sungsam; Hong, Jin Hee; Park, Jin-Sung; Lim, Yong-Sik; Park, Hong-Gyu; Choi, Wonshik

2018-05-01

The efficient delivery of light energy is a prerequisite for the non-invasive imaging and stimulating of target objects embedded deep within a scattering medium. However, the injected waves experience random diffusion by multiple light scattering, and only a small fraction reaches the target object. Here, we present a method to counteract wave diffusion and to focus multiple-scattered waves at the deeply embedded target. To realize this, we experimentally inject light into the reflection eigenchannels of a specific flight time to preferably enhance the intensity of those multiple-scattered waves that have interacted with the target object. For targets that are too deep to be visible by optical imaging, we demonstrate a more than tenfold enhancement in light energy delivery in comparison with ordinary wave diffusion cases. This work will lay a foundation to enhance the working depth of imaging, sensing and light stimulation.

Energy efficiency through energy audit

International Nuclear Information System (INIS)

Esan, A. A.

2000-08-01

Energy is an essential factor to economic and social development and improved standards of living in developing countries. Nigeria in particular. There is a strong need for greater energy efficiency in every sector of economy in order to reduce costs. enhance competitiveness, conserve energy resources and reduce environmental impacts associated with production, distribution and use of energy. Energy auditing and monitoring has a significant role in any energy management and conservation project. Energy auditing as an important part of industrial energy management on plant level, represents a complex of activities aiming at the efficient use of energy. The activities are undertaken by a team of experts who use a set of measuring instruments to monitor and evaluate all the necessary data to elaborate a package of recommendations on improvements in the field of energy efficiency and possible product quality. The inefficient conversion and use of energy have been identified as a central problem for all developing countries, Nigeria inclusive, since they all consume significantly higher amounts of energy per unit of GDP than OECD countries. This aggravates energy-related environmental problems and is also a burden on domestic resources and foreign exchange. Energy prices have risen drastically in many developing countries, while energy intensities remain high. Price changes alone are not rapidly translating energy efficiency improvements. Identifying and removing the obstacles to greater energy efficiency should be priority for government in developing countries. This is why the Energy Commission, an apex organ of government on Energy matters in all its ramifications is out to encourage relatively low-cost energy audits for the Textile industries - such audits can identify ''good house-keeping's' measures, such as simply process improvements, that reduce energy consumption and operating costs. This will be followed by the training of plant workers/energy managers

Energy efficiency in the British housing stock: Energy demand and the Homes Energy Efficiency Database

International Nuclear Information System (INIS)

Hamilton, Ian G.; Steadman, Philip J.; Bruhns, Harry; Summerfield, Alex J.; Lowe, Robert

2013-01-01

The UK Government has unveiled an ambitious retrofit programme that seeks significant improvement to the energy efficiency of the housing stock. High quality data on the energy efficiency of buildings and their related energy demand is critical to supporting and targeting investment in energy efficiency. Using existing home improvement programmes over the past 15 years, the UK Government has brought together data on energy efficiency retrofits in approximately 13 million homes into the Homes Energy Efficiency Database (HEED), along with annual metered gas and electricity use for the period of 2004–2007. This paper describes the HEED sample and assesses its representativeness in terms of dwelling characteristics, the energy demand of different energy performance levels using linked gas and electricity meter data, along with an analysis of the impact retrofit measures has on energy demand. Energy savings are shown to be associated with the installation of loft and cavity insulation, and glazing and boiler replacement. The analysis illustrates this source of ‘in-action’ data can be used to provide empirical estimates of impacts of energy efficiency retrofit on energy demand and provides a source of empirical data from which to support the development of national housing energy efficiency retrofit policies. - Highlights: • The energy efficiency level for 50% of the British housing stock is described. • Energy demand is influenced by size and age and energy performance. • Housing retrofits (e.g. cavity insulation, glazing and boiler replacements) save energy. • Historic differences in energy performance show persistent long-term energy savings

Policies of energy efficiency in Vietnam. Proceedings of the International conference on policies of energy efficiency, Ho-Chi-Minh-Ville, 9 and 10 April 2008

International Nuclear Information System (INIS)

Bourguinat, Elisabeth; Breton-Moyet, Laurence; Gromard, Christian de; Henry, Alain; Nguyen Dinh Hiep; Mohanty, Brahmanand; Salomon, Sophie; Nguyen Tran The; Le Hoang Viet; Nguyen Thi Thu Giang; Lopez, Jose; Vu Hong Van Anh

2009-10-01

This book contains the contributions and debates of an international conference on policies of energy efficiency. This conference comprised six sessions which respectively addressed: energy challenges and public policies (world energetic challenges and perspective, economic and efficient use of energy in Vietnam, French arrangements of the policy for energy management, example of policies of energy efficiency in the ASEAN, initiating energetic change in developing economies), urban planning and housing (for a low carbon urban planning, energy and housing regulation in Vietnam, projects of energy efficiency in buildings by the AFD in China and Thailand, energy management in public lighting projects), urban management and urban mobility (financing and planning issues for urban transports and energy efficiency, energy efficiency and strategy of development and management of transports, an energy-urban planning-environment integrated approach in Ho-Chi-Minh-Ville), energy in industry and in services (incentive tools for energy saving in Vietnam, concept and challenges for emerging countries for the management of energy demand, credit lines for energy or carbon saving, the experience of energy saving certificates by EDF), opportunities and pricing for renewable energies (objectives and conditions for a policy of support to renewable energies, overview of renewable energies in Vietnam, tariffs applied to small renewable energy plants in function of avoided costs, economic and pricing conditions for wind energy), and relationships between energy efficiency, public policies and decentralisation (the role of competitiveness poles, impact of public policies in a region, role and responsibility of a decentralised structure in Vietnam, implementation of the national energy policy in the four provinces of South-Vietnam)

Renewable energy sources: Energy Efficiency Agency

International Nuclear Information System (INIS)

Bulgarensky, Mihael

2004-01-01

The paper presents the activities of the Energy Efficiency Agency, its main functions, as well as the new legislation stimulating the use of RES, stipulated in the new Energy Law of Bulgaria. The second part of the paper describes the potential of renewable energy in i.e. wind energy; solar energy; biomass energy; hydro energy; geothermal energy; draft of a National Program on RES 2005-2015. The third part describes the main issues of the new ENERGY EFFICIENCY LAW and the established Energy efficiency fund. (Author)

Energy Efficiency Collaboratives

Energy Technology Data Exchange (ETDEWEB)

Li, Michael [US Department of Energy, Washington, DC (United States); Bryson, Joe [US Environmental Protection Agency, Washington, DC (United States)

2015-09-01

Collaboratives for energy efficiency have a long and successful history and are currently used, in some form, in more than half of the states. Historically, many state utility commissions have used some form of collaborative group process to resolve complex issues that emerge during a rate proceeding. Rather than debate the issues through the formality of a commission proceeding, disagreeing parties are sent to discuss issues in a less-formal setting and bring back resolutions to the commission. Energy efficiency collaboratives take this concept and apply it specifically to energy efficiency programs—often in anticipation of future issues as opposed to reacting to a present disagreement. Energy efficiency collaboratives can operate long term and can address the full suite of issues associated with designing, implementing, and improving energy efficiency programs. Collaboratives can be useful to gather stakeholder input on changing program budgets and program changes in response to performance or market shifts, as well as to provide continuity while regulators come and go, identify additional energy efficiency opportunities and innovations, assess the role of energy efficiency in new regulatory contexts, and draw on lessons learned and best practices from a diverse group. Details about specific collaboratives in the United States are in the appendix to this guide. Collectively, they demonstrate the value of collaborative stakeholder processes in producing successful energy efficiency programs.

A framework to characterize energy efficiency measures

International Nuclear Information System (INIS)

Trianni, Andrea; Cagno, Enrico; De Donatis, Alessio

2014-01-01

Highlights: • A novel framework to characterize energy efficiency measures is proposed. • It allows a greater knowledge sharing, facilitating the adoption of the best measures. • It supports policy-makers in developing drivers for industrial energy efficiency. - Abstract: The need to increase the diffusion of energy efficiency measures (EEMs) is of crucial importance to achieve a consistent reduction of energy consumption and green house gases (GHG) emissions. A clear comprehension of the characteristics of such EEMs could assist in gathering and capitalizing all the information needed by industrial firms in selecting and adopting technologies, as well as by policy-makers in designing appropriate policies for their diffusion. Therefore, in this study, starting from a literature review of the studies analyzing the attributes of EEMs, we aim at providing an innovative and comprehensive framework to characterize such measures, based on 17 attributes grouped according to six categories, such as: economic, energy, environmental, production-related, implementation-related and the possible interaction with other systems. We applied this scheme to an extensive range of EEMs in cross-cutting technologies, i.e. motors, compressed air, lighting and HVAC systems. The analysis provides a relevant contribution firstly to the structuring and the sharing of knowledge on EEMs and hence to the comprehension of the barriers currently hindering their adoption; secondly, it provides a structured basis for the analysis of the drivers that policy-makers should develop in order to promote industrial energy efficiency

Energy-Efficient Office Buildings at High Latitudes

Energy Technology Data Exchange (ETDEWEB)

Lerum, V.

1996-12-31

This doctoral thesis describes a method for energy efficient office building design at high latitudes and cold climates. The method combines daylighting, passive solar heating, solar protection, and ventilative cooling. The thesis focuses on optimal design of an equatorial-facing fenestration system. A spreadsheet framework linking existing simplified methods is used. The daylight analysis uses location specific data on frequency distribution of diffuse daylight on vertical surfaces to estimate energy savings from optimal window and room configurations in combination with a daylight-responsive electric lighting system. The passive solar heating analysis is a generalization of a solar load ratio method adapted to cold climates by combining it with the Norwegian standard NS3031 for winter months when the solar savings fraction is negative. The emphasis is on very high computational efficiency to permit rapid and comprehensive examination of a large number of options early in design. The procedure is illustrated for a location in Trondheim, Norway, testing the relative significance of various design improvement options relative to a base case. The method is also tested for two other locations in Norway, at latitudes 58 and 70 degrees North. The band of latitudes between these limits covers cities in Alaska, Canada, Greenland, Iceland, Scandinavia, Finland, Russia, and Northern Japan. A comprehensive study of the ``whole building approach`` shows the impact of integrated daylighting and low-energy design strategies. In general, consumption of lighting electricity may be reduced by 50-80%, even at extremely high latitudes. The reduced internal heat from electric lights is replaced by passive solar heating. 113 refs., 85 figs., 25 tabs.

Light energy management in peach: utilization, photoprotection , photodamage and recovery. Maximizing light absorption in orchard is not always the best solution

OpenAIRE

Losciale, Pasquale

2008-01-01

The relation between the intercepted light and orchard productivity was considered linear, although this dependence seems to be more subordinate to planting system rather than light intensity. At whole plant level not always the increase of irradiance determines productivity improvement. One of the reasons can be the plant intrinsic un-efficiency in using energy. Generally in full light only the 5 – 10% of the total incoming energy is allocated to net photosynthesis. Therefore preserving or i...

Dark states and delocalization: Competing effects of quantum coherence on the efficiency of light harvesting systems.

Science.gov (United States)

Hu, Zixuan; Engel, Gregory S; Alharbi, Fahhad H; Kais, Sabre

2018-02-14

Natural light harvesting systems exploit electronic coupling of identical chromophores to generate efficient and robust excitation transfer and conversion. Dark states created by strong coupling between chromophores in the antenna structure can significantly reduce radiative recombination and enhance energy conversion efficiency. Increasing the number of the chromophores increases the number of dark states and the associated enhanced energy conversion efficiency yet also delocalizes excitations away from the trapping center and reduces the energy conversion rate. Therefore, a competition between dark state protection and delocalization must be considered when designing the optimal size of a light harvesting system. In this study, we explore the two competing mechanisms in a chain-structured antenna and show that dark state protection is the dominant mechanism, with an intriguing dependence on the parity of the number of chromophores. This dependence is linked to the exciton distribution among eigenstates, which is strongly affected by the coupling strength between chromophores and the temperature. Combining these findings, we propose that increasing the coupling strength between the chromophores can significantly increase the power output of the light harvesting system.

Virtual Generation (Energy Efficiency) The Cheapest Source For Power Generation

Energy Technology Data Exchange (ETDEWEB)

Hasnie, Sohail

2010-09-15

Energy efficiency is the cheapest source of energy that has escaped the minds of the politicians in the developing countries. This paper argues for large scale utility led end use efficiency programs in a new paradigm, where 1 million efficient light bulbs is synonymous to a 50 MW power station that costs only 2% of the traditional fossil fuel power station and zero maintenance. Bulk procurement, setting up new standards and generation of certified emissions reduction is part of this strategy. It discusses implementation of a $20 million pilot in the Philippines supported by the Asian Development Bank.

Lighting and social practices - what role does lighting play for low energy house (LEH) households and LED frontrunners?

DEFF Research Database (Denmark)

Jensen, Charlotte Louise

As lighting in Danish households consume approximately 1.3 TWh every year, reducing electricity consumption from lighting is important. Studies have shown that a mere substitution of inefficient lighting technologies towards more efficient ones may not be possible, as many social and cultural...... dimensions influence how people use and relate to lighting. Assessing how very distinctive contexts of households (that diverge from an exemplary kind of household), such as low energy houses and LED frontrunner households, use and understand lighting, may give some insight into what may trigger or hamper...

Analysis of the Chinese Market for Building Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

Yu, Sha [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Evans, Meredydd [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shi, Qing [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-03-20

China will account for about half of the new construction globally in the coming decade. Its floorspace doubled from 1996 to 2011, and Chinese rural buildings alone have as much floorspace as all of U.S. residential buildings. Building energy consumption has also grown, increasing by over 40% since 1990. To curb building energy demand, the Chinese government has launched a series of policies and programs. Combined, this growth in buildings and renovations, along with the policies to promote green buildings, are creating a large market for energy efficiency products and services. This report assesses the impact of China’s policies on building energy efficiency and on the market for energy efficiency in the future. The first chapter of this report introduces the trends in China, drawing on both historical analysis, and detailed modeling of the drivers behind changes in floorspace and building energy demand such as economic and population growth, urbanization, policy. The analysis describes the trends by region, building type and energy service. The second chapter discusses China’s policies to promote green buildings. China began developing building energy codes in the 1980s. Over time, the central government has increased the stringency of the code requirements and the extent of enforcement. The codes are mandatory in all new buildings and major renovations in China’s cities, and they have been a driving force behind the expansion of China’s markets for insulation, efficient windows, and other green building materials. China also has several other important policies to encourage efficient buildings, including the Three-Star Rating System (somewhat akin to LEED), financial incentives tied to efficiency, appliance standards, a phasing out of incandescent bulbs and promotion of efficient lighting, and several policies to encourage retrofits in existing buildings. In the third chapter, we take “deep dives” into the trends affecting key building components

Progress with Implementing Energy Efficiency Policies in the G8

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

At the 2008 G8 Summit in Hokkaido, leaders reaffirmed the critical role improved energy efficiency can play in addressing energy security, environmental and economic objectives. They went even farther than in previous Summits and committed to maximising implementation of the 25 IEA energy efficiency recommendations prepared for the G8. The imperative to enhance energy efficiency remains a priority for all countries. To support governments with their implementation of energy efficiency, the IEA recommended the adoption of a broad range of specific energy efficiency policy measures to the G8 Summits in 2006, 2007 and 2008. The consolidated set of recommendations from these Summits covers 25 fields of action across seven priority areas: cross-sectoral activity, buildings, appliances, lighting, transport, industry and power utilities. If governments want to significantly improve energy efficiency, the IEA considers that no single policy implemented in isolation will be effective at achieving this aim. The IEA Secretariat recommends that governments implement a full set of appropriate measures. The IEA estimates that if implemented globally without delay, the proposed actions could save around 8.2 GtCO2/yr by 2030 -- equivalent to twice the EU's yearly emissions. This report evaluates the progress of the G8 countries in implementing energy efficiency policy, including the 25 G8/IEA recommendations. Information in this report is current up to 31 March 2009.

Options to improve energy efficiency for educational building

Science.gov (United States)

Jahan, Mafruha

The cost of energy is a major factor that must be considered for educational facility budget planning purpose. The analysis of energy related issues and options can be complex and requires significant time and detailed effort. One way to facilitate the inclusion of energy option planning in facility planning efforts is to utilize a tool that allows for quick appraisal of the facility energy profile. Once such an appraisal is accomplished, it is then possible to rank energy improvement options consistently with other facility needs and requirements. After an energy efficiency option has been determined to have meaningful value in comparison with other facility planning options, it is then possible to utilize the initial appraisal as the basis for an expanded consideration of additional facility and energy use detail using the same analytic system used for the initial appraisal. This thesis has developed a methodology and an associated analytic model to assist in these tasks and thereby improve the energy efficiency of educational facilities. A detailed energy efficiency and analysis tool is described that utilizes specific university building characteristics such as size, architecture, envelop, lighting, occupancy, thermal design which allows reducing the annual energy consumption. Improving the energy efficiency of various aspects of an educational building's energy performance can be complex and can require significant time and experience to make decisions. The approach developed in this thesis initially assesses the energy design for a university building. This initial appraisal is intended to assist administrators in assessing the potential value of energy efficiency options for their particular facility. Subsequently this scoping design can then be extended as another stage of the model by local facility or planning personnel to add more details and engineering aspects to the initial screening model. This approach can assist university planning efforts to

An Efficient Composition for Bengal Lights.

Science.gov (United States)

Comet, M.; Schreyeck, L.; Fuzellier, H.

2002-01-01

Reports the discovery of an efficient base composition for making bengal lights that is obtained with potassium chlorate and thiourea. Combining this mixture with appropriate flame coloring can produce several impressive bengal lights. (DDR)

Cost-Benefit Analysis and Emission Reduction of Energy Efficient Lighting at the Universiti Tenaga Nasional

Science.gov (United States)

Ganandran, G. S. B.; Mahlia, T. M. I.; Ong, Hwai Chyuan; Rismanchi, B.; Chong, W. T.

2014-01-01

This paper reports the result of an investigation on the potential energy saving of the lighting systems at selected buildings of the Universiti Tenaga Nasional. The scope of this project includes evaluation of the lighting system in the Library, Admin Building, College of Engineering, College of Information Technology, Apartments, and COE Food court of the university. The main objectives of this project are to design the proper retrofit scenario and to calculate the potential electricity saving, the payback period, and the potential environmental benefits. In this survey the policy for retrofitting the old lighting system with the new energy saving LEDs starts with 10% for the first year and continues constantly for 10 years until all the lighting systems have been replaced. The result of the life cycle analysis reveals that after four years, the selected buildings will bring profit for the investment. PMID:25133258

Cost-Benefit Analysis and Emission Reduction of Energy Efficient Lighting at the Universiti Tenaga Nasional

Directory of Open Access Journals (Sweden)

G. S. B. Ganandran

2014-01-01

Full Text Available This paper reports the result of an investigation on the potential energy saving of the lighting systems at selected buildings of the Universiti Tenaga Nasional. The scope of this project includes evaluation of the lighting system in the Library, Admin Building, College of Engineering, College of Information Technology, Apartments, and COE Food court of the university. The main objectives of this project are to design the proper retrofit scenario and to calculate the potential electricity saving, the payback period, and the potential environmental benefits. In this survey the policy for retrofitting the old lighting system with the new energy saving LEDs starts with 10% for the first year and continues constantly for 10 years until all the lighting systems have been replaced. The result of the life cycle analysis reveals that after four years, the selected buildings will bring profit for the investment.

The role of energy losses in photosynthetic light harvesting

NARCIS (Netherlands)

Kruger, T. P. J.; van Grondelle, R.

2017-01-01

Photosynthesis operates at the bottom of the food chain to convert the energy of light into carbohydrates at a remarkable global rate of about 130 TW. Nonetheless, the overall photosynthetic process has a conversion efficiency of a few percent at best, significantly less than bottom-up photovoltaic

ImBuild: Impact of building energy efficiency programs

Energy Technology Data Exchange (ETDEWEB)

Scott, M.J.; Hostick, D.J.; Belzer, D.B.

1998-04-01

As part of measuring the impact of government programs on improving the energy efficiency of the Nation`s building stock, the Department of Energy Office of Building Technology, State and Community Programs (BTS) is interested in assessing the economic impacts of its portfolio of programs, specifically the potential impact on national employment and income. The special-purpose version of the IMPLAN model used in this study is called ImBuild. In comparison with simple economic multiplier approaches, such as Department of Commerce RIMS 2 system, ImBuild allows for more complete and automated analysis of the economic impacts of energy efficiency investments in buildings. ImBuild is also easier to use than existing macroeconomic simulation models. The authors conducted an analysis of three sample BTS energy programs: the residential generator-absorber heat exchange gas heat pump (GAX heat pump), the low power sulfur lamp (LPSL) in residential and commercial applications, and the Building America program. The GAX heat pump would address the market for the high-efficiency residential combined heating and cooling systems. The LPSL would replace some highly efficient fluorescent commercial lighting. Building America seeks to improve the energy efficiency of new factory-built, modular, manufactured, and small-volume, site-built homes through use of systems engineering concepts and early incorporation of new products and processes, and by increasing the demand for more energy-efficient homes. The authors analyze a scenario for market penetration of each of these technologies devised for BTS programs reported in the BTS GPRA Metrics Estimates, FY99 Budget Request, December 19, 1997. 46 figs., 4 tabs.

Design and Analysis of Hybrid Solar Lighting and Full-Spectrum Solar Energy Systems

International Nuclear Information System (INIS)

Muhs, J.D.

2001-01-01

This paper describes a systems-level design and analysis of a new approach for improving the energy efficiency and affordability of solar energy in buildings, namely, hybrid solar lighting and full-spectrum solar energy systems. By using different portions of the solar spectrum simultaneously for multiple end-use applications in buildings, the proposed system offers unique advantages over other alternatives for using sunlight to displace electricity (conventional topside daylighting and solar technologies). Our preliminary work indicates that hybrid solar lighting, a method of collecting and distributing direct sunlight for lighting purposes, will alleviate many of the problems with passive daylighting systems of today, such as spatial and temporal variability, glare, excess illumination, cost, and energy efficiency. Similarly, our work suggests that the most appropriate use of the visible portion of direct, nondiffuse sunlight from an energy-savings perspective is to displace electric light rather than generate electricity. Early estimates detailed in this paper suggest an anticipated system cost of well under$2.0/Wp and 5-11(cents)/kWh for displaced and generated electricity in single-story commercial building applications. Based on a number of factors discussed in the paper, including sunlight availability, building use scenarios, time-of-day electric utility rates, cost, and efficacy of the displaced electric lights, the simple payback of this approach in many applications could eventually be well under 5 years

ENERGY EFFICIENT BUILDINGS PROGRAM. CHAPTER FROM THE ENERGY AND ENVIRONMENT DIVISION ANNUAL REPORT 1979

Energy Technology Data Exchange (ETDEWEB)

Authors, Various

1979-12-01

The research reported in this volume was undertaken during FY 1979 within the Energy & Environment Division of the Lawrence Berkeley Laboratory. This volume will comprise a section of the Energy & Environment Division 1979 Annual Report, to be published in the summer of 1980. Work reported relate to: thermal performance of building envelopes; building ventilation and indoor air quality; a computer program for predicting energy use in buildings; study focused specifically on inherently energy intensive hospital buildings; energy efficient windows and lighting; potential for energy conservation and savings in the buildings sector; and evaluation of energy performance standards for residential buildings.

Reconsidering energy efficiency

International Nuclear Information System (INIS)

Goldoni, Giovanni

2007-01-01

Energy and environmental policies are reconsidering energy efficiency. In a perfect market, rational and well informed consumers reach economic efficiency which, at the given prices of energy and capital, corresponds to physical efficiency. In the real world, market failures and cognitive frictions distort the consumers from perfectly rational and informed choices. Green incentive schemes aim at balancing market failures and directing consumers toward more efficient goods and services. The problem is to fine tune the incentive schemes [it

A Traffic Prediction Algorithm for Street Lighting Control Efficiency

Directory of Open Access Journals (Sweden)

POPA Valentin

2013-01-01

Full Text Available This paper presents the development of a traffic prediction algorithm that can be integrated in a street lighting monitoring and control system. The prediction algorithm must enable the reduction of energy costs and improve energy efficiency by decreasing the light intensity depending on the traffic level. The algorithm analyses and processes the information received at the command center based on the traffic level at different moments. The data is collected by means of the Doppler vehicle detection sensors integrated within the system. Thus, two methods are used for the implementation of the algorithm: a neural network and a k-NN (k-Nearest Neighbor prediction algorithm. For 500 training cycles, the mean square error of the neural network is 9.766 and for 500.000 training cycles the error amounts to 0.877. In case of the k-NN algorithm the error increases from 8.24 for k=5 to 12.27 for a number of 50 neighbors. In terms of a root means square error parameter, the use of a neural network ensures the highest performance level and can be integrated in a street lighting control system.

High coupling efficiency of foam spherical hohlraum driven by 2ω laser light

Science.gov (United States)

Chen, Yao-Hua; Lan, Ke; Zheng, Wanguo; Campbell, E. M.

2018-02-01

The majority of solid state laser facilities built for laser fusion research irradiate targets with third harmonic light (0.35 μm) up-converted from the fundamental Nd wavelength at 1.05 μm. The motivation for this choice of wavelength is improved laser-plasma coupling. Significant disadvantages to this choice of wavelength are the reduced damage threshold of optical components and the efficiency of energy conversion to third harmonic light. Both these issues are significantly improved if second harmonic (0.53 μm) radiation is used, but theory and experiments have shown lower optical to x-ray energy conversion efficiency and increased levels of laser-plasma instabilities, resulting in reduced laser-target coupling. In this letter, we propose to use a 0.53 μm laser for the laser ignition facilities and use a low density foam wall to increase the coupling efficiency from the laser to the capsule and present two-dimensional radiation-hydrodynamic simulations of 0.53 μm laser light irradiating an octahedral-spherical hohlraum with a low density foam wall. The simulations show that the reduced optical depth of the foam wall leads to an increased laser-light conversion into thermal x-rays and about 10% higher radiation flux on the capsule than that achieved with 0.35 μm light irradiating a solid density wall commonly used in laser indirect drive fusion research. The details of the simulations and their implications and suggestions for wavelength scaling coupled with innovative hohlraum designs will be discussed.

Influences on the thermal efficiency of energy piles

International Nuclear Information System (INIS)

Cecinato, Francesco; Loveridge, Fleur A.

2015-01-01

Energy piles have recently emerged as a viable alternative to borehole heat exchangers, but their energy efficiency has so far seen little research. In this work, a finite element numerical model is developed for the accurate 3D analysis of transient diffusive and convective heat exchange phenomena taking place in geothermal structures. The model is validated by reproducing both the outcome of a thermal response test carried out on a test pile, and the average response of the linear heat source analytical solution. Then, the model is employed to carry out a parametric analysis to identify the key factors in maximising the pile energy efficiency. It is shown that the most influential design parameter is the number of pipes, which can be more conveniently increased, within a reasonable range, compared to increasing the pile dimensions. The influence of changing pile length, concrete conductivity, pile diameter and concrete cover are also discussed in light of their energetic implications. Counter to engineering intuition, the fluid flowrate does not emerge as important in energy efficiency, provided it is sufficient to ensure turbulent flow. The model presented in this paper can be easily adapted to the detailed study of other types of geothermal structures. - Highlights: • A numerical model for 3D thermal transient analysis of energy piles is developed. • The model is validated against both field data and an analytical solution. • Key parameters are then identified for efficient thermal design of energy piles. • Energy efficiency is maximised by large pipe number and concrete conductivity. • Large exchanger fluid velocity does not have a major impact on efficiency

High-Efficiency Nitride-Based Solid-State Lighting

Energy Technology Data Exchange (ETDEWEB)

Paul T. Fini; Shuji Nakamura

2005-07-30

In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light

The efficiency challenge of nitride light-emitting diodes for lighting

KAUST Repository

Weisbuch, Claude; Piccardo, Marco; Martinelli, Lucio; Iveland, Justin; Peretti, Jacques; Speck, James S.

2015-01-01

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. We discuss the challenges of light-emitting diodes in view of their application to solid-state lighting. The requirement is to at least displace the quite efficient fluorescent, sodium, and high

Energy transfer efficiency measurements in a theta-pinch

International Nuclear Information System (INIS)

Cavalcanti, G.H.; Luna, F.R.T.; Trigueiros, A.G.

1993-01-01

An increase in energy transfer efficiency of the capacitor bank to the plasma was obtained when the electrical system of a theta-pinch was changed so that the ratio of total inductance to coil inductance was switched of 1/6 to 1/2. A further increase about 20% was obtained for 16/1 ratio. The measurements were made through the current discharge decay, and the spectral analysis of the emitted light from theta-pinch shows a correspondent efficiency increase. (author)

The efficiency of photovoltaic cells exposed to pulsed laser light

Science.gov (United States)

Lowe, R. A.; Landis, G. A.; Jenkins, P.

1993-01-01

Future space missions may use laser power beaming systems with a free electron laser (FEL) to transmit light to a photovoltaic array receiver. To investigate the efficiency of solar cells with pulsed laser light, several types of GaAs, Si, CuInSe2, and GaSb cells were tested with the simulated pulse format of the induction and radio frequency (RF) FEL. The induction pulse format was simulated with an 800-watt average power copper vapor laser and the RF format with a frequency-doubled mode-locked Nd:YAG laser. Averaged current vs bias voltage measurements for each cell were taken at various optical power levels and the efficiency measured at the maximum power point. Experimental results show that the conversion efficiency for the cells tested is highly dependent on cell minority carrier lifetime, the width and frequency of the pulses, load impedance, and the average incident power. Three main effects were found to decrease the efficiency of solar cells exposed to simulated FEL illumination: cell series resistance, LC 'ringing', and output inductance. Improvements in efficiency were achieved by modifying the frequency response of the cell to match the spectral energy content of the laser pulse with external passive components.

Can nanophotonics control the Förster resonance energy transfer efficiency?

DEFF Research Database (Denmark)

Blum, C.; Zijlstra, N.; Lagendijk, A.

2013-01-01

from photovoltaics and lighting, to probing molecular distances and interactions.It is an intriguing open question whether the FRET rate γFRET and the energy transfer efficiency ηFRET can also be controlled by the nanoscale optical environment, characterized by the local density of optical states (LDOS...... precisely-defined, isolated, and efficient donor-acceptor pairs. The FRET pairs are dye molecules that covalently bound to the opposite ends of a 15 basepair long double-stranded with a precisely defined distance of 6.8 nm. Control over the LDOS is realized by positioning the FRET systems at well...... of the energy donor by the LDOS, the energy transfer efficiency can be enhanced or reduced. If a donor with unit quantum efficiency is placed in a 3D photonic bandgap, the energy transfer efficiency will approach 100 %, independent of the acceptor, and of the distances and orientations between the FRET partners....

Energy efficiency in public buildings; Eficiencia energetica em predios publicos

Energy Technology Data Exchange (ETDEWEB)

Kiperstok, Asher; Garcia, Agenor Gomes Pinto; Vianna, Luis Gustavo; Freitas, Daniela; Oliveira, Braulio; Azevedo, Alexandre; Alves, Igor; Fagundes, Vitor Lacerda [Universidade Federal da Bahia (TECLIM/UFBA), Salvador, BA (Brazil). Rede de Tecnologias Limpas

2010-07-01

The implementation process of a energy management system in buildings of the Bahia state administration is presented. Completed a first phase, with a prior knowledge of the characteristics of the energy use in buildings and the implementation of a daily consumption monitoring system (the Vianet), a second phase begins with the definition of consumption targets and mobilization actions of the people, both the whole of the users, and more strongly the 'eco team', group which shall be responsible for the management. This paper makes a theoretical consideration on the use of energy in buildings, showing the room for energy management in addition to the simple exchange by efficient equipment, estimates the reduction obtained by the energy efficiency program of the electric utility with the exchange of light fixtures and air conditioners, shows the targeting process and difficulties found and identifies measures that will be implemented to achieve increasingly efficient patterns of energy use. (author)

Hierarchical Graphene Foam for Efficient Omnidirectional Solar-Thermal Energy Conversion.

Science.gov (United States)

Ren, Huaying; Tang, Miao; Guan, Baolu; Wang, Kexin; Yang, Jiawei; Wang, Feifan; Wang, Mingzhan; Shan, Jingyuan; Chen, Zhaolong; Wei, Di; Peng, Hailin; Liu, Zhongfan

2017-10-01

Efficient solar-thermal energy conversion is essential for the harvesting and transformation of abundant solar energy, leading to the exploration and design of efficient solar-thermal materials. Carbon-based materials, especially graphene, have the advantages of broadband absorption and excellent photothermal properties, and hold promise for solar-thermal energy conversion. However, to date, graphene-based solar-thermal materials with superior omnidirectional light harvesting performances remain elusive. Herein, hierarchical graphene foam (h-G foam) with continuous porosity grown via plasma-enhanced chemical vapor deposition is reported, showing dramatic enhancement of broadband and omnidirectional absorption of sunlight, which thereby can enable a considerable elevation of temperature. Used as a heating material, the external solar-thermal energy conversion efficiency of the h-G foam impressively reaches up to ≈93.4%, and the solar-vapor conversion efficiency exceeds 90% for seawater desalination with high endurance. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Efficiency Control in Iridium Complex-Based Phosphorescent Light-Emitting Diodes

Directory of Open Access Journals (Sweden)

Boucar Diouf

2012-01-01

Full Text Available Key factors to control the efficiency in iridium doped red and green phosphorescent light emitting diodes (PhOLEDs are discussed in this review: exciton confinement, charge trapping, dopant concentration and dopant molecular structure. They are not independent from each other but we attempt to present each of them in a situation where its specific effects are predominant. A good efficiency in PhOLEDs requires the triplet energy of host molecules to be sufficiently high to confine the triplet excitons within the emitting layer (EML. Furthermore, triplet excitons must be retained within the EML and should not drift into the nonradiative levels of the electron or hole transport layer (resp., ETL or HTL; this is achieved by carefully choosing the EML’s adjacent layers. We prove how reducing charge trapping results in higher efficiency in PhOLEDs. We show that there is an ideal concentration for a maximum efficiency of PhOLEDs. Finally, we present the effects of molecular structure on the efficiency of PhOLEDs using red iridium complex dopant with different modifications on the ligand to tune its highest occupied molecular orbital (HOMO and lowest unoccupied molecular orbital (LUMO energies.

Future indoor light and associated energy consumption based on professionals' visions: A practice- and network-oriented analysis

DEFF Research Database (Denmark)

Franceschini, Simone; Borup, Mads; Rosales-Carreón, Jesús

2018-01-01

Through the insight and visions of Danish lighting experts, this manuscript investigates relationships between future lighting technologies and practices and the expected impacts on energy and lighting consumption. The light-emitting diode (LED) will be the dominant technology of the future smart...... light systems. Though, energy efficiency is expected to improve, new market players will appear and new lighting opportunites will be exploited that, in turn, will increase the demand for light. A rebound effect is expected. The overall impact on the future consumption of energy is uncertain, so we...

Energy efficiency in buildings. Yearbook 2013; Energieeffizienz in Gebaeuden. Jahrbuch 2013

Energy Technology Data Exchange (ETDEWEB)

Poeschk, Juergen (ed.)

2013-06-01

The book under consideration presents current political controversies and technical solutions. Numerous practical examples show in detail how the German building stock for energy transition can be made fit. 40 technical papers shed light on the following topics: policy strategies, efficiency concepts on the test stand, districts and quarters, positive results: The house as an energy source, energy storage facilities for buildings, and smart energy.

Analysis of Minimum Efficiency Performance Standards for Residential General Service Lighting in Chile

Energy Technology Data Exchange (ETDEWEB)

Letschert, Virginie E.; McNeil, Michael A.; Leiva Ibanez, Francisco Humberto; Ruiz, Ana Maria; Pavon, Mariana; Hall, Stephen

2011-06-01

Minimum Efficiency Performance Standards (MEPS) have been chosen as part of Chile's national energy efficiency action plan. As a first MEPS, the Ministry of Energy has decided to focus on a regulation for lighting that would ban the sale of inefficient bulbs, effectively phasing out the use of incandescent lamps. Following major economies such as the US (EISA, 2007) , the EU (Ecodesign, 2009) and Australia (AS/NZS, 2008) who planned a phase out based on minimum efficacy requirements, the Ministry of Energy has undertaken the impact analysis of a MEPS on the residential lighting sector. Fundacion Chile (FC) and Lawrence Berkeley National Laboratory (LBNL) collaborated with the Ministry of Energy and the National Energy Efficiency Program (Programa Pais de Eficiencia Energetica, or PPEE) in order to produce a techno-economic analysis of this future policy measure. LBNL has developed for CLASP (CLASP, 2007) a spreadsheet tool called the Policy Analysis Modeling System (PAMS) that allows for evaluation of costs and benefits at the consumer level but also a wide range of impacts at the national level, such as energy savings, net present value of savings, greenhouse gas (CO2) emission reductions and avoided capacity generation due to a specific policy. Because historically Chile has followed European schemes in energy efficiency programs (test procedures, labelling program definitions), we take the Ecodesign commission regulation No 244/2009 as a starting point when defining our phase out program, which means a tiered phase out based on minimum efficacy per lumen category. The following data were collected in order to perform the techno-economic analysis: (1) Retail prices, efficiency and wattage category in the current market, (2) Usage data (hours of lamp use per day), and (3) Stock data, penetration of efficient lamps in the market. Using these data, PAMS calculates the costs and benefits of efficiency standards from two distinct but related perspectives: (1) The

Energy efficient design

International Nuclear Information System (INIS)

1991-01-01

Solar Applications and Energy Efficiency in Building Design and Town Planning (RER/87/006) is a United Nations Development Programme (UNDP) project of the Governments of Albania, Bulgaria, Cyprus, The Czech and Slovak Federal Republic, France, Hungary, Malta, Poland, Turkey, United Kingdom and Yugoslavia. The project began in 1988 and comes to a conclusion at the end of 1991. It is to enhance the professional skills of practicing architects, engineers and town planners in European countries to design energy efficient buildings which reduce energy consumption and make greater use of passive solar heating and natural cooling techniques. The United Nations Economic Commission for Europe (ECE) is the Executing Agency of the project which is implemented under the auspices of the Committee on Energy, General Energy Programme of Work for 1990-1994, sub-programme 5 Energy Conservation and Efficiency (ECE/ENERGY/15). The project has five main outputs or results: an international network of institutions for low energy building design; a state-of-the-art survey of energy use in the built environment of European IPF countries; a simple computer program for energy efficient building design; a design guide and computer program operators' manual; and a series of international training courses in participating European IPF countries. Energy Efficient Design is the fourth output of the project. It comprises the design guide for practicing architects and engineers, for use mainly in mid-career training courses, and the operators' manual for the project's computer program

Fully Integrated Solar Energy Harvester and Sensor Interface Circuits for Energy-Efficient Wireless Sensing Applications

Directory of Open Access Journals (Sweden)

Maher Kayal

2013-02-01

Full Text Available This paper presents an energy-efficient solar energy harvesting and sensing microsystem that harvests solar energy from a micro-power photovoltaic module for autonomous operation of a gas sensor. A fully integrated solar energy harvester stores the harvested energy in a rechargeable NiMH microbattery. Hydrogen concentration and temperature are measured and converted to a digital value with 12-bit resolution using a fully integrated sensor interface circuit, and a wireless transceiver is used to transmit the measurement results to a base station. As the harvested solar energy varies considerably in different lighting conditions, in order to guarantee autonomous operation of the sensor, the proposed area- and energy-efficient circuit scales the power consumption and performance of the sensor. The power management circuit dynamically decreases the operating frequency of digital circuits and bias currents of analog circuits in the sensor interface circuit and increases the idle time of the transceiver under reduced light intensity. The proposed microsystem has been implemented in a 0.18 µm complementary metal-oxide-semiconductor (CMOS process and occupies a core area of only 0.25 mm2. This circuit features a low power consumption of 2.1 µW when operating at its highest performance. It operates with low power supply voltage in the 0.8V to 1.6 V range.

Study of Sequential Dexter Energy Transfer in High Efficient Phosphorescent White Organic Light-Emitting Diodes with Single Emissive Layer

Science.gov (United States)

Kim, Jin Wook; You, Seung Il; Kim, Nam Ho; Yoon, Ju-An; Cheah, Kok Wai; Zhu, Fu Rong; Kim, Woo Young

2014-11-01

In this study, we report our effort to realize high performance single emissive layer three color white phosphorescent organic light emitting diodes (PHOLEDs) through sequential Dexter energy transfer of blue, green and red dopants. The PHOLEDs had a structure of; ITO(1500 Å)/NPB(700 Å)/mCP:Firpic-x%:Ir(ppy)3-0.5%:Ir(piq)3-y%(300 Å)/TPBi(300 Å)/Liq(20 Å)/Al(1200 Å). The dopant concentrations of FIrpic, Ir(ppy)3 and Ir(piq)3 were adjusted and optimized to facilitate the preferred energy transfer processes attaining both the best luminous efficiency and CIE color coordinates. The presence of a deep trapping center for charge carriers in the emissive layer was confirmed by the observed red shift in electroluminescent spectra. White PHOLEDs, with phosphorescent dopant concentrations of FIrpic-8.0%:Ir(ppy)3-0.5%:Ir(piq)3-0.5% in the mCP host of the single emissive layer, had a maximum luminescence of 37,810 cd/m2 at 11 V and a luminous efficiency of 48.10 cd/A at 5 V with CIE color coordinates of (0.35, 0.41).

Tunable light extraction efficiency of GaN light emitting diodes by ZnO nanorod arrays

International Nuclear Information System (INIS)

Chao, C H; Lin, W H; Lin, C F; Chen, C H; Changjean, C H

2009-01-01

We report the influence of ZnO nanorod arrays (NRAs) on the light extraction efficiency of GaN light emitting diodes (LEDs). Our investigation indicates that the output light intensity of the device exhibits a periodic oscillation as a function of the rod length. The variation of light extraction efficiency is caused by the Fabry–Perot resonance of the film composed of the nanorods. The theoretical analysis shows a good agreement with the measurement results. Our study reveals a method to control the output light extraction efficiency of GaN LEDs via a simple solution-based synthesized ZnO NRAs

POST OCCUPANCY EVALUATION OF ENERGY-EFFICIENT BUILDINGS IN TROPICAL CLIMATES – MALAYSIA

Directory of Open Access Journals (Sweden)

Ban-Huat Ng

2013-07-01

Full Text Available There exists a well-known gap between occupants and building’s energy-efficient designs. A comprehensive building performance diagnostic technique, Post Occupancy Evaluation (POE may surpass the current evaluation method by reducing the gap between occupants and building’s energy-efficient design. Due to these reasons, the aim of this research is to identify the problems with respect to energy-efficient design which affect occupants’ comfort. This research focuses on the application of energy-efficient design in office building and was conducted on energy-efficient buildings in Malaysia. A building performance survey framework, Energy-efficient Building Environmental Quality Questionnaire (EBEQ2, was  used to identify the problems affecting occupants’ comfort and buildings’ Indoor Environmental Quality (IEQ. The result was analyzed using Statistical Package for Social Science (SPSS. The research outcome shows that majority of occupants are not satisfied  with the thermal comfort and lighting condition of  the buildings. Building certified with sustainable building rating tools does not guarantee better IEQ performance. Thus  continuous research is needed to ensure energy-efficient building concept is applied effectively in each type of building.

Energy efficiency and social equity in South Africa: seeking convergence

Energy Technology Data Exchange (ETDEWEB)

Van Horen, C.; Simmonds, G. [University of Cape Town, Rondebosch (South Africa). Energy and Development Research Centre

1998-09-01

A key challenge facing post-apartheid South Africa is to achieve a balance between equity and efficiency goals. On the one hand, the democratic government wishes to improve the quality of life of the majority of the population, whilst on the other, the country needs an efficient and internationally competitive economy. At the more specific level of household energy policy, this efficiency-equity linkage represents a key challenge for policy-making and implementation: it is essential that convergence is sought between household energy strategies aimed at improving energy efficiency, and those strategies which improve the living conditions of the poor. This paper begins by reviewing developments in South Africa`s household energy sector in the early-1990s, most notably the national electrification plan which was launched in 1991. A second development, in 1994, was the establishment of the National Electricity Regulator. Despite the attention given to energy efficiency in the government`s new energy policy, energy efficiency considerations have not yet emerged as a major force in the energy sector. Electricity prices underestimated the environmental and other impacts of coal and nuclear-generated electricity. A range of economic and institutional reasons for this are identified and considered. Finally, two interventions on which some progress has been made, are described: these include insulation and thermal performance projects in new lost-cost houses, and a compact fluorescent lighting programme. 37 refs., 4 figs.

Do energy efficiency measures promote the use of renewable sources?

International Nuclear Information System (INIS)

Marques, Antonio C.; Fuinhas, Jose A.

2011-01-01

This paper analyses the factors behind the deployment of renewable energy, focusing particularly on the effect of energy efficiency policies and measures. The impact of these factors is appraised within the context of several phases of the use of renewable sources. We therefore apply the quantile regression technique to a set of 21 European Countries in two time spans: from 1990 to 1998, and from 1999 to 2006. We control variables of policy, environment, socioeconomic characteristics, and electricity generation. For the second period, energy efficiency policies and measures concerning renewable sources effectively promote renewables, namely in the take-off phase. We shed light on the lobbying effect of traditional energy industries, showing that it depends both on the period under analysis, and on the kind of traditional energy source.

Overall energy conversion efficiency of a photosynthetic vesicle

Energy Technology Data Exchange (ETDEWEB)

Sener, Melih [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, United States; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States; Strumpfer, Johan [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, United States; Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, United States; Singharoy, Abhishek [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, United States; Hunter, C. Neil [Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom; Schulten, Klaus [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, United States; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States; Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, United States

2016-08-26

The chromatophore of purple bacteria is an intracellular spherical vesicle that exists in numerous copies in the cell and that efficiently converts sunlight into ATP synthesis, operating typically under low light conditions. Building on an atomic-level structural model of a low-light-adapted chromatophore vesicle from Rhodobacter sphaeroides, we investigate the cooperation between more than a hundred protein complexes in the vesicle. The steady-state ATP production rate as a function of incident light intensity is determined after identifying quinol turnover at the cytochrome bc1 complex (cytbc1) as rate limiting and assuming that the quinone/quinol pool of about 900 molecules acts in a quasi-stationary state. For an illumination condition equivalent to 1% of full sunlight, the vesicle exhibits an ATP production rate of 82 ATP molecules/s. The energy conversion efficiency of ATP synthesis at illuminations corresponding to 1%–5% of full sunlight is calculated to be 0.12-0.04, respectively. The vesicle stoichiometry, evolutionarily adapted to the low light intensities in the habitat of purple bacteria, is suboptimal for steady-state ATP turnover for the benefit of protection against over-illumination.

Energy efficient policy impact in India: case study of investment in industrial energy efficiency

International Nuclear Information System (INIS)

Yang, M.

2006-01-01

The objective of this paper is to identify the effectiveness of energy policy and capital investment in energy efficiency technologies in the industrial sector in India. Indian energy policies relating to industrial energy efficiency over the past 25 years are briefly reviewed, and a comparison study of these energy efficiency policies and strategies in India and China has been carried out. Interviews were conducted with a number of government policy-making institutions and a national industrial development bank. The accounts of 26 industrial enterprises which applied and used a loan of the Asian Development Bank were audited for data collection. Field-visits to seven industrial entrepreneurs were undertaken in a case study. Methodologies used in this study include documentation, cross-country reviews on energy policies, questionnaire design and distribution in the industrial sector, and on-site auditing of energy efficiency technologies. This paper concludes that current energy policies and strategies in India need further improvement to promote energy efficiency investment and energy efficiency technology development in the industrial sector. This paper will interest those policy makers and industrial entrepreneurs who are willing to finance energy efficiency projects and improve energy efficiency in the industrial sector. (author)

Energy efficiency policy impact in India: case study of investment in industrial energy efficiency

International Nuclear Information System (INIS)

Yang Ming

2006-01-01

The objective of this paper is to identify the effectiveness of energy policy and capital investment in energy efficiency technologies in the industrial sector in India. Indian energy policies relating to industrial energy efficiency over the past 25 years are briefly reviewed, and a comparison study of these energy efficiency policies and strategies in India and China has been carried out. Interviews were conducted with a number of government policy-making institutions and a national industrial development bank. The accounts of 26 industrial enterprises which applied and used a loan of the Asian Development Bank were audited for data collection. Field-visits to seven industrial entrepreneurs were undertaken in a case study. Methodologies used in this study include documentation, cross-country reviews on energy policies, questionnaire design and distribution in the industrial sector, and on-site auditing of energy efficiency technologies. This paper concludes that current energy policies and strategies in India need further improvement to promote energy efficiency investment and energy efficiency technology development in the industrial sector. This paper will interest those policy makers and industrial entrepreneurs who are willing to finance energy efficiency projects and improve energy efficiency in the industrial sector

Regulation proposal for voluntary energy efficiency labelling of commercial buildings

International Nuclear Information System (INIS)

Lamberts, Roberto; Goulart, Solange; Carlo, Joyce; Westphal, Fernando

2006-01-01

Despite of Brazil not being between the major world energy consumers, the consumption of electricity has significantly increased in the late years. The National Energy Balance of 2005, published by the Brazilian Ministry of Energy, showed an increasing of the participation of electricity in the final energy consumption of 15.7% in 2002 to 16.2% in 2004. Initially, a brief review of the initiatives taken by Brazilian Government aiming to limit and control the energy consumption in buildings is presented. Then, the regulation proposal containing the technical requirements to classify the energy efficiency level of buildings is shown. The purpose of this voluntary regulation is to provide conditions to certify the energy efficiency level of Brazilian buildings (commercial and public). It specifies the methods for energy efficiency rating of buildings and includes requirements to attend energy conservation measures in three main issues: lighting system; air conditioning system and envelope. The regulation applies to large buildings (minimum total area of 500 m 2 or when the energy demand is greater than or equal to 2,3 kV, including: Conditioned buildings; Partially conditioned buildings and Naturally ventilated buildings. (author)

Energy efficiency : an economic stimulator; Efficacite energetique : un moteur economique vert

Energy Technology Data Exchange (ETDEWEB)

Contant, A.

2009-04-01

In an effort to meet Quebec's energy requirements projected for 2015, Hydro-Quebec along with its partners and clients will invest $3 billion in energy efficiency. Quebec's Energy Efficiency Agency, Canada's Office of Energy Efficiency and the Federation of Canadian Municipalities (FCM) green municipal fund have all contributed to energy efficiency projects to stimulate the economy. These measures are expected to create nearly 4000 jobs in Quebec for electricians, heating contractors, plumbers and building professionals. This investment will also benefit the suppliers and distributors of electrical materials as well as the forestry industry, cement manufacturers, and specialized engineers. Since the benefits of energy efficiency upgrades are already well established, projects can get underway without further studies. The proposed energy efficiency projects can be applied anywhere in the province of Quebec and are not intended for any specific region. To name a few, the projects have included energy upgrades in an arena in Riviere du Loup, the Montreal Health Institute's head office building, and traffic light upgrades in Levis, Quebec. The article noted that energy efficiency upgrades made in the office buildings of Alcan, IBM, Molson and Bombardier have all resulted in at least a 5 per cent reduction in electricity use. All these changes have been good for the environment, even though Quebec's electricity is generated almost entirely from renewable energy sources. 6 figs.

Efficient conversion of solar energy to biomass and electricity.

Science.gov (United States)

Parlevliet, David; Moheimani, Navid Reza

2014-01-01

The Earth receives around 1000 W.m(-2) of power from the Sun and only a fraction of this light energy is able to be converted to biomass (chemical energy) via the process of photosynthesis. Out of all photosynthetic organisms, microalgae, due to their fast growth rates and their ability to grow on non-arable land using saline water, have been identified as potential source of raw material for chemical energy production. Electrical energy can also be produced from this same solar resource via the use of photovoltaic modules. In this work we propose a novel method of combining both of these energy production processes to make full utilisation of the solar spectrum and increase the productivity of light-limited microalgae systems. These two methods of energy production would appear to compete for use of the same energy resource (sunlight) to produce either chemical or electrical energy. However, some groups of microalgae (i.e. Chlorophyta) only require the blue and red portions of the spectrum whereas photovoltaic devices can absorb strongly over the full range of visible light. This suggests that a combination of the two energy production systems would allow for a full utilization of the solar spectrum allowing both the production of chemical and electrical energy from the one facility making efficient use of available land and solar energy. In this work we propose to introduce a filter above the algae culture to modify the spectrum of light received by the algae and redirect parts of the spectrum to generate electricity. The electrical energy generated by this approach can then be directed to running ancillary systems or producing extra illumination for the growth of microalgae. We have modelled an approach whereby the productivity of light-limited microalgae systems can be improved by at least 4% through using an LED array to increase the total amount of illumination on the microalgae culture.

Principles of light energy management

Science.gov (United States)

Davis, N.

1994-01-01

Six methods used to minimize excess energy effects associated with lighting systems for plant growth chambers are reviewed in this report. The energy associated with wall transmission and chamber operating equipment and the experimental requirements, such as fresh air and internal equipment, are not considered here. Only the energy associated with providing and removing the energy for lighting is considered.

Energy efficiency: 2004 world overview

International Nuclear Information System (INIS)

2004-01-01

Since 1992 the World Energy Council (WEC) has been collaborating with ADEME (Agency for Environment and Energy Efficiency, France) on a joint project 'Energy Efficiency Policies and Indicators'. APERC (Asia Pacific Energy Research Centre) and OLADE (Latin American Energy Organisation) have also participated in the study, which has been monitoring and evaluating energy efficiency policies and their impacts around the world. WEC Member Committees have been providing data and information and ENERDATA (France) has provided technical assistance. This report, published in August 2004, presents and evaluates energy efficiency policies in 63 countries, with a specific focus on five policy measures, for which in-depth case studies were prepared by selected experts: - Minimum energy efficiency standards for household electrical appliances; - Innovative energy efficiency funds; - Voluntary/negotiated agreements on energy efficiency/ CO 2 ; - Local energy information centres; - Packages of measures. In particular, the report identifies the policy measures, which have proven to be the most effective, and can be recommended to countries which have recently embarked on the development and implementation of energy demand management policies. During the past ten years, the Kyoto Protocol and, more recently, emerging concerns about security of supply have raised, both the public and the political profile of energy efficiency. Almost all OECD countries and an increasing number of other countries are implementing energy efficiency policies adapted to their national circumstances. In addition to the market instruments (voluntary agreements, labels, information, etc.), regulatory measures are widely introduced where the market fails to give the right signals (buildings, appliances). In developing countries, energy efficiency is equally important, even if the drivers are different compared to industrialized countries. Reduction of greenhouse gas emissions and local pollution often have a

Energy efficiency; Energieffektivisering

Energy Technology Data Exchange (ETDEWEB)

2009-06-15

The Low Energy Panel will halve the consumption in buildings. The Panel has proposed a halving of consumption in the construction within 2040 and 20 percent reduction in the consumption in the industry within 2020. The Panel consider it as possible to gradually reduce consumption in buildings from the current level of 80 TWh with 10 TWh in 2020, 25 TWh in 2030 and 40 TWh in 2040. According the committee one such halving can be reached by significant efforts relating to energy efficiency, by greater rehabilitations, energy efficiency in consisting building stock and stricter requirements for new construction. For the industry field the Panel recommend a political goal to be set at least 20 percent reduction in specific energy consumption in the industry and primary industry beyond general technological development by the end of 2020. This is equivalent to approximately 17 TWh based on current level of activity. The Panel believes that a 5 percent reduction should be achieved by the end of 2012 by carrying out simple measures. The Low Energy Panel has since March 2009 considered possibilities to strengthen the authorities' work with energy efficiency in Norway. The wide complex panel adds up proposals for a comprehensive approach for increased energy efficiency in particular in the building- and industry field. The Panel has looked into the potential for energy efficiency, barriers for energy efficiency, assessment of strengths and weaknesses in the existing policy instruments and members of the Panel's recommendations. In addition the report contains a review of theoretical principles for effects of instruments together with an extensive background. One of the committee members have chosen to take special notes on the main recommendations in the report. (AG)

Energy Efficiency Center - Overview

International Nuclear Information System (INIS)

Obryk, E.

2000-01-01

Full text: The Energy Efficiency Center (EEC) activities have been concentrated on Energy Efficiency Network (SEGE), education and training of energy auditors. EEC has started studies related to renewable fuels (bio fuel, wastes) and other topics related to environment protection. EEC has continued close collaboration with Institute for Energy Technology, Kjeller, Norway. It has been organized and conducted Seminar and Workshop on ''How to Reduce Energy and Water Cost in Higher Education Buildings'' for general and technical managers of the higher education institutions. This Seminar was proceeded by the working meeting on energy efficiency strategy in higher education at the Ministry of National Education. EEC has worked out proposal for activities of Cracow Regional Agency for Energy Efficiency and Environment and has made offer to provide services for this Agency in the field of training, education and consulting. The vast knowledge and experiences in the field of energy audits have been used by the members of EEC in lecturing at energy auditors courses authorized by the National Energy Efficiency Agency (KAPE). Altogether 20 lectures have been delivered. (author)

Energy efficiency; Efficacite energetique

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-06-15

This road-map proposes by the Group Total aims to inform the public on the energy efficiency. It presents the energy efficiency and intensity around the world with a particular focus on Europe, the energy efficiency in industry and Total commitment. (A.L.B.)

Energy efficiency by intelligent streetlighting systems. Interview with two representatives of ZVEI; Energie dank intelligenter Strassenbeleuchtungstechnik effizient nutzen. Interview mit zwei ZVEI-Repraesentanten

Energy Technology Data Exchange (ETDEWEB)

Anon.

2008-02-15

Current energy-political decisions aim at energy conservation and higher efficiency. In 2005, lighting accounted for nearly ten percent of the total energy consumption. Streetlighting is one of the biggest consumers in this sector. netzpraxis interviewed Christoph Hess and Dr. Juergen Waldorf about the industry's views on how efficiency in streetlighting may be enhanced. (orig.)

Energy efficiency in Swedish industry

International Nuclear Information System (INIS)

Zhang, Shanshan; Lundgren, Tommy; Zhou, Wenchao

2016-01-01

This paper assesses energy efficiency in Swedish industry. Using unique firm-level panel data covering the years 2001–2008, the efficiency estimates are obtained for firms in 14 industrial sectors by using data envelopment analysis (DEA). The analysis accounts for multi-output technologies where undesirable outputs are produced alongside with the desirable output. The results show that there was potential to improve energy efficiency in all the sectors and relatively large energy inefficiencies existed in small energy-use industries in the sample period. Also, we assess how the EU ETS, the carbon dioxide (CO_2) tax and the energy tax affect energy efficiency by conducting a second-stage regression analysis. To obtain consistent estimates for the regression model, we apply a modified, input-oriented version of the double bootstrap procedure of Simar and Wilson (2007). The results of the regression analysis reveal that the EU ETS and the CO_2 tax did not have significant influences on energy efficiency in the sample period. However, the energy tax had a positive relation with the energy efficiency. - Highlights: • We use DEA to estimate firm-level energy efficiency in Swedish industry. • We examine impacts of climate and energy policies on energy efficiency. • The analyzed policies are Swedish carbon and energy taxes and the EU ETS. • Carbon tax and EU ETS did not have significant influences on energy efficiency. • The energy tax had a positive relation with energy efficiency.

Energy efficiency throughout the world. On the way to transition

International Nuclear Information System (INIS)

Dessus, Benjamin; Laponche, Bernard; Blaustein, Edgar; Chappoz, Loic; Labrousse, Michel; Humberset, Suzanne; Peullemeulle, Justine; Magnin, Gerard; Lacassagne, Sylvie; Bertinat, Pablo; Soumaila, Ibrahim; Rialhe, Anne; Clain, Cristina; Poveda, Mentor; Scalambrini Coasta, Heitor; Diniz, Silvio; Osman, Nejib; Singh, Daljit; Sant, Girish; Kokino, Issairo; Methe Myrand, Lea; Raoust, Michel; Novel, Aymeric; Narain, Sunita; D'Monte, Darryl; Lopez, Jose; Mohanty, Brahmanand; Mezghani, Mohamed; Chamonin, Denis

2012-10-01

This document gathers several articles from different countries on different topics related to energy transition. The first part deals with the challenge of energy efficiency as a mean on the way to energy transition (in France, in Europe, in Latin America, in Asian developing countries). The second part illustrates through examples the importance of governance issues and political will (access to energy in West Africa, a network in Latin America and the Caribbean, use of LEDs for public lighting in Brazil, Tunisian policy, role of regulation authorities, situation in India). The third part proposes examples illustrating the importance of the local dimension in any policy aimed at energy efficiency (a project in Africa, public support in housing construction in Austin, the Swedish city of Vaxjo, the French city of Montdidier, the example of two quarters of Geneva using the lake water as cooling or heating source, the refrigerator fleet in a Palestinian village). The last part reports several experiments made in different sectors (building thermal rehabilitation in China, green buildings in India, the building sector in India, a new strategy in India for domestic and commercial electric equipment, stimulation of energy efficiency in the Japanese industry, public transport in sub-Saharan cities, energy efficiency in Indian agriculture)

Improving energy efficiency in the transportation sector

Energy Technology Data Exchange (ETDEWEB)

Plotkin, S.E.

1994-12-31

A primary characteristic of transportation in the United States is its high per capita energy consumption. The average US citizen consumes nearly five times as much energy for transportation as the average Japanese and nearly three times as much as the average citizen of France, Britain, or West Germany. The energy efficiency of US transportation has improved substantially over the past two decades (both absolutely and in comparison to Europe), and US travel volume has grown more slowly than in most of the developed world. However, the United States still consumes more than one-third of the world`s transport energy. Also, 96 percent of US transport energy is in the form of oil products. This is more oil than the United States produces, despite its position as one of the world`s largest oil producers. With current problems and expectation of continued growth in travel and energy use, Congress has increasingly turned to transportation energy conservation - in the form of improvements in the technical efficiency of travel, increases in load factors, reductions in travel demand, shifting to alternative fuels, and shifts to more efficient travel modes - as an important policy goal. For example, the Clean Air Amendments of 1990 incorporate transportation demand management as a critical tool in reducing urban air pollution. Legislation proposed in the 102d Congress sought rigorous new automobile and light truck fuel economy standards. With continued increases in U.S. oil imports, urban traffic congestion, and greenhouse gas emissions, and the failure of many urban areas to meet air quality standards, strong congressional interest in new energy conservation initiates is likely to continue.

Constructing regulation and regulating for energy efficient construction

Energy Technology Data Exchange (ETDEWEB)

Shove, Elizabeth [Lancaster University (United Kingdom). Centre for the Study of Environmental Change

1998-07-01

This project considers the process of formulating energy-related building regulation in the light of the revisions to Part L (Conservation of Fuel and Power) of the Building Regulations for England and Wales. Details are given of the main objectives of the research, namely, the examination of the roles of the UK government, local government and pressure groups in shaping energy efficiency standards, the impacts of environmental regulations, the limits of energy-related regulation, environmental regulation of the building sector, and the features of energy related building control. This control is compared with current practice in other European countries. The methodology of the project involving the review of governmental documents and interviews is described. (UK)

Eco-innovation dynamics and sustainability – new perspectives in innovation studies illuminated through the case of lighting and its energy consumption

DEFF Research Database (Denmark)

Franceschini, Simone

There is an increasing consensus about the need to reduce the environmental burden of economic activities. The concept of sustainable development has led to increased efficiency of the economic process through innovation, which is now the main strategy applied both to preserve environmental capital...... and to achieve economic growth. Consequently, many innovations have been given the label of “eco” due to their ability to improve the efficiency of the economic process. The history of energy consumption is a paradigmatic example of diffusion of this type of eco-innovations. The efficiency of converting energy...... of energy during the provision of light. Researchers have already investigated the dynamics of production and consumption associated with the most recent light “revolutions”. Interestingly, these revolutions resulted in increased energy consumption for the provision of light, even if energy efficiency...

Export orientation and domestic electricity generation: Effects on energy efficiency innovation in select sectors

International Nuclear Information System (INIS)

Urpelainen, Johannes

2011-01-01

Why are some countries developing many energy efficiency innovations, while others are lagging behind? I argue that export orientation and electricity at low variable cost from nuclear and hydropower plants have an interactive effect on energy efficiency innovation. Export-oriented countries have strong incentives to invest in energy efficiency innovation, as they are in a position to export these technology innovations for global markets. But if inexpensive electricity is supplied in a country, the domestic demand for energy efficiency innovation is missing, and so the home market cannot serve as a springboard for international commercialization. I test this theory against international patent data on energy efficiency innovation in insulation, heating, and lighting for 22 OECD countries, 1991-2007. The statistical analysis indicates that export orientation has large positive effects on energy efficiency innovation in countries that do not rely on nuclear and hydroelectricity. - Highlights: → Export-oriented countries produce energy efficiency innovations. → Nuclear and hydropower reduce energy efficiency innovation. → Data on international patents from industrialized countries support the argument.

Energy Efficient Hybrid Gas Separation with Ionic Liquids

DEFF Research Database (Denmark)

Liu, Xinyan; Liang, Xiaodong; Gani, Rafiqul

2017-01-01

Shale gas, like natural gas, contains H2, CO2, CH4 and that light hydrocarbon gases needs processing to separate the gases for conversion to higher value products. Currently, distillation based separation is employed, which is energy intensive. Hybrid gas separation processes, combining absorption...... systems is established for process design-analysis. A strategy for hybrid gas separation process synthesis where distillation and IL-based absorption are employed for energy efficient gas processing is developed and its application is highlighted for a model shale gas processing case study....

Communication and Energy Efficiency in Visual Sensor Networks for People Localization

Energy Technology Data Exchange (ETDEWEB)

Karakaya, Mahmut [ORNL; Qi, Hairong [ORNL

2012-01-01

This paper addresses the communication and energy efficiency in collaborative visual sensor networks (VSNs) for people localization, a challenging computer vision problem of its own. We focus on the design of a light-weight and energy efficient solution where people are localized based on distributed camera nodes integrating the so-called certainty map generated at each node, that records the target non-existence information within the camera s field of view. We first present a dynamic itinerary for certainty map integration where not only each sensor node transmits a very limited amount of data but that a limited number of camera nodes is involved. Then, we perform a comprehensive analytical study to evaluate communication and energy efficiency between different integration schemes, i.e., centralized and distributed integration. Based on results obtained from analytical study and real experiments, the distributed method shows effectiveness in detection accuracy as well as energy and bandwidth efficiency.

Energy-efficient sensing in wireless sensor networks using compressed sensing.

Science.gov (United States)

Razzaque, Mohammad Abdur; Dobson, Simon

2014-02-12

Sensing of the application environment is the main purpose of a wireless sensor network. Most existing energy management strategies and compression techniques assume that the sensing operation consumes significantly less energy than radio transmission and reception. This assumption does not hold in a number of practical applications. Sensing energy consumption in these applications may be comparable to, or even greater than, that of the radio. In this work, we support this claim by a quantitative analysis of the main operational energy costs of popular sensors, radios and sensor motes. In light of the importance of sensing level energy costs, especially for power hungry sensors, we consider compressed sensing and distributed compressed sensing as potential approaches to provide energy efficient sensing in wireless sensor networks. Numerical experiments investigating the effectiveness of compressed sensing and distributed compressed sensing using real datasets show their potential for efficient utilization of sensing and overall energy costs in wireless sensor networks. It is shown that, for some applications, compressed sensing and distributed compressed sensing can provide greater energy efficiency than transform coding and model-based adaptive sensing in wireless sensor networks.

Energy efficiency in U.S. residential rental housing: Adoption rates and impact on rent

International Nuclear Information System (INIS)

Im, Jongho; Seo, Youngme; Cetin, Kristen S.; Singh, Jasmeet

2017-01-01

Highlights: •Rental units listings collected and analyzed for 10 U.S. cities. •Energy efficient features included in 5.3–21.6% of rental units in each city. •The most common efficient features are lighting and appliance upgrades. •Propensity score matching and conditional mean comparison methods used. •Generally, energy efficient features increases the units’ rent, overall from 6% to 14%. -- Abstract: For 118 million residential housing units in the U.S., there is currently a gap between the potential energy savings that can be achieved through the use of existing energy efficiency technologies, and the actual level of energy savings realized, particularly for the 37% of housing units that are considered residential rental properties. Additional quantifiable benefits are needed beyond energy savings to help further motivate residential property owners to invest in energy efficiency upgrades. This research focuses on assessing the adoption of energy efficient upgrades in U.S. residential housing and the impact on rental prices. Ten U.S. cities are chosen for analysis; these cities vary in size across multiple climate zones, and represent a diverse set of housing market conditions. Data was collected for over 159,000 rental property listings, their characteristics, and their energy efficiency measures listed in rental housing postings across each city. Following an extensive data quality control process, over thirty different types energy efficient features were identified. The level of adoption was determined for each city, ranging from 5.3% to 21.6%. Efficient lighting and appliances were among the most common, with many features doubling as energy efficient and other desirable aesthetic or comfort improvements. Then using propensity score matching and conditional mean comparison methods, the relative impact on rent charged in each city was calculated, which ranged from a 6% to 14.1% increase in rent for properties with energy efficient features

Optical meta-atom for localization of light with quantized energy.

Science.gov (United States)

Lannebère, Sylvain; Silveirinha, Mário G

2015-10-30

The capacity to confine light into a small region of space is of paramount importance in many areas of modern science. Here we suggest a mechanism to store a quantized 'bit' of light--with a very precise amount of energy--in an open core-shell plasmonic structure ('meta-atom') with a nonlinear optical response. Notwithstanding the trapped light state is embedded in the radiation continuum, its lifetime is not limited by the radiation loss. Interestingly, it is shown that the interplay between the nonlinear response and volume plasmons enables breaking fundamental reciprocity restrictions, and coupling very efficiently an external light source to the meta-atom. The collision of an incident optical pulse with the meta-atom may be used to release the trapped light 'bit'.

Summary of Country Reports Submitted to the Energy Efficiency Working Party - September 2010

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

The purpose of this summary report is to highlight energy efficiency policy action and planning in IEA member countries since the last meeting of the Energy Efficiency Working Party (EEWP)1 held in January 2010. This paper provides an overview of energy efficiency developments across all sectors, but is not meant to be a comprehensive review of every energy efficiency-related policy in IEA member countries. At the request of the EEWP, this issue of the country report summary focuses primarily on transport. Countries reported a wide range of energy efficiency policy activity. Compared with past reports, energy efficiency policy planning seems to be giving way to programme implementation in the buildings, lighting and appliances sectors. Planning and implementation is underway in the transport sector. Measures in the transport sector are diverse and include financial support for electric vehicle R&D and pilot projects, fiscal policies to encourage the purchase of efficient vehicles, eco-drive programmes and vehicle labelling. Measures of note outside the transport sector include the promotion of smart metering.

Energy efficiency networks; Energieeffizienz-Netzwerke

Energy Technology Data Exchange (ETDEWEB)

Gruber, Anna [Forschungsgesellschaft fuer Energiewirtschaft mbH (FfE GmbH), Muenchen (Germany)

2011-07-01

Energy efficiency networks are an attractive method to increase the energy efficiency and to reduce the costs and CO{sub 2} emissions of the companies operating in this network. A special feature of the energy efficiency networks is the exchange of experiences and training of the energy managers. Energy efficiency networks consist of about ten to fifteen locally domiciled companies. During the project period of three to four years, there are two main phases. In the first phase, the initial consultation phase, the actual state of a company is captured, and measures to increase the efficiency and energy conservation are identified. Parallel to this, in the second phase every three months a meeting with the participating companies takes place. Experience exchange and implementation of energy efficiency measures are the focus of these meetings. Initial studies show that the increase of the energy efficiency during participating in the energy efficiency network almost can be doubled in comparison to the average of the industry.

Energy efficiency and CO2: is electricity the key factor?

Energy Technology Data Exchange (ETDEWEB)

Bamberger, Y.

2007-07-01

Europe must face soon to the depletion of fossil energy resources. Efficiency in end energy uses is a key to prepare this challenge. First, the report shows that significant energy efficiency capacities remain in the main economy sectors in France and Europe: buildings, industry, transportation. The key technologies, mainly electricity-driven, are briefly presented, together with the related main tracks for R and D: heat pumps, thermal insulation, induction and mechanical vapour compression for industry, plugged hybrid vehicle, LED sources for lighting. Their ability to decrease CO2 emissions is shown. Control equipment and users behaviour are pointed out, mainly with the key role of price energy with recent French experience : load shifting, peak shaving. Finally, the report shows that a firm policy, based on high performance equipments, could lead to a significant decrease of energy needs in France around 2030.

Energy efficient heating and ventilation of large halls

CERN Document Server

Hojer, Ondrej; Kabele, Karel; Kotrbaty, Miroslav; Sommer, Klaus; Petras, Dusan

2011-01-01

This guidebook is focused on modern methods for design, control and operation of energy efficient heating systems in large spaces and industrial halls. The book deals with thermal comfort, light and dark gas radiant heaters, panel radiant heating, floor heating and industrial air heating systems. Various heating systems are illustrated with case studies. Design principles, methods and modeling tools are presented for various systems.

Evaluation and Optimization of a Traditional North-Light Roof on Industrial Plant Energy Consumption

Energy Technology Data Exchange (ETDEWEB)

Adriaenssens, Sigrid [Form-Finding Lab, Department of Civil and Environmental Engineering, School of Engineering and Applied Science, Princeton Univ., NJ (United States); Hao Liu [Center for Intelligent and Networked Systems, Department of Automation, Tsinghua National Laboratory for Information Science and Technology, Tsinghua University, Beijing (China); Wahed, Miriam [Form-Finding Lab, Department of Civil and Environmental Engineering, School of Engineering and Applied Science, Princeton Univ., NJ (United States); Qianchuan Zhao [Center for Intelligent and Networked Systems, Department of Automation, Tsinghua National Laboratory for Information Science and Technology, Tsinghua University, Beijing (China)

2013-04-15

Increasingly strict energy policies, rising energy prices, and a desire for a positive corporate image currently serve as incentives for multinational corporations to reduce their plants’ energy consumption. This paper quantitatively investigates and discusses the value of a traditional north-light roof using a complete building energy simulation and optimization framework. The findings indicate that the north-light system yields positive building energy performance for several climate zones, including: (i) Humid Subtropical; (ii) Semiarid Continental; (iii) Mediterranean; and (iv) Subtropical Highland. In the Subtropical Highland climate zone, for example, the building energy consumption of a north-light roof is up to 54% less than that of a conventional flat roof. Based on these positive findings, this paper further presents an optimization framework that alters the north-light roof shape to further improve its energy performance. To quantitatively guarantee a high probability of finding satisfactory designs while reducing the computational processing time, ordinal optimization is introduced into the scheme. The Subtropical Highland case study shows further energy building consumption reduction of 26% for an optimized north-light roof shape. The presented evaluation and optimization framework could be used in designing a plant with integrated north-lights roof that aim at energy efficiency while maintaining environmental occupant comfort levels.

USE Efficiency -- Universities and Students for Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

Melandri, Daniela

2010-09-15

Universities and Student for Energy Efficiency is a European Project within the Intelligent Energy Programme. It intends to create a common stream for energy efficiency systems in university buildings. Universities and students are proposed as shining examples for energy efficiency solutions and behaviour. The Project involves 10 countries and has the aim to improve energy efficiency in university buildings. Students are the main actors of the project together with professors and technicians. To act on students means to act on direct future market players in diffusion of public opinions. A strong communication action supports the succeeding of the action.

Energy efficiency

International Nuclear Information System (INIS)

Marvillet, Ch.; Tochon, P.; Mercier, P.

2004-01-01

World energy demand is constantly rising. This is a legitimate trend, insofar as access to energy enables enhanced quality of life and sanitation levels for populations. On the other hand, such increased consumption generates effects that may be catastrophic for the future of the planet (climate change, environmental imbalance), should this growth conform to the patterns followed, up to recent times, by most industrialized countries. Reduction of greenhouse gas emissions, development of new energy sources and energy efficiency are seen as the major challenges to be taken up for the world of tomorrow. In France, the National Energy Debate indeed emphasized, in 2003, the requirement to control both demand for, and offer of, energy, through a strategic orientation law for energy. The French position corresponds to a slightly singular situation - and a privileged one, compared to other countries - owing to massive use of nuclear power for electricity generation. This option allows France to be responsible for a mere 2% of worldwide greenhouse gas emissions. Real advances can nonetheless still be achieved as regards improved energy efficiency, particularly in the transportation and residential-tertiary sectors, following the lead, in this respect, shown by industry. These two sectors indeed account for over half of the country CO 2 emissions (26% and 25% respectively). With respect to transportation, the work carried out by CEA on the hydrogen pathway, energy converters, and electricity storage has been covered by the preceding chapters. As regards housing, a topic addressed by one of the papers in this chapter, investigations at CEA concern integration of the various devices enabling value-added use of renewable energies. At the same time, the organization is carrying through its activity in the extensive area of heat exchangers, allowing industry to benefit from improved understanding in the modeling of flows. An activity evidenced by advances in energy efficiency for

Resource use efficiency of closed plant production system with artificial light: concept, estimation and application to plant factory.

Science.gov (United States)

Kozai, Toyoki

2013-01-01

Extensive research has recently been conducted on plant factory with artificial light, which is one type of closed plant production system (CPPS) consisting of a thermally insulated and airtight structure, a multi-tier system with lighting devices, air conditioners and fans, a CO2 supply unit, a nutrient solution supply unit, and an environment control unit. One of the research outcomes is the concept of resource use efficiency (RUE) of CPPS.This paper reviews the characteristics of the CPPS compared with those of the greenhouse, mainly from the viewpoint of RUE, which is defined as the ratio of the amount of the resource fixed or held in plants to the amount of the resource supplied to the CPPS.It is shown that the use efficiencies of water, CO2 and light energy are considerably higher in the CPPS than those in the greenhouse. On the other hand, there is much more room for improving the light and electric energy use efficiencies of CPPS. Challenging issues for CPPS and RUE are also discussed.

High efficiency light harvesting by carotenoids in the LH2 complex from photosynthetic bacteria: unique adaptation to growth under low-light conditions.

Science.gov (United States)

Magdaong, Nikki M; LaFountain, Amy M; Greco, Jordan A; Gardiner, Alastair T; Carey, Anne-Marie; Cogdell, Richard J; Gibson, George N; Birge, Robert R; Frank, Harry A

2014-09-25

Rhodopin, rhodopinal, and their glucoside derivatives are carotenoids that accumulate in different amounts in the photosynthetic bacterium, Rhodoblastus (Rbl.) acidophilus strain 7050, depending on the intensity of the light under which the organism is grown. The different growth conditions also have a profound effect on the spectra of the bacteriochlorophyll (BChl) pigments that assemble in the major LH2 light-harvesting pigment-protein complex. Under high-light conditions the well-characterized B800-850 LH2 complex is formed and accumulates rhodopin and rhodopin glucoside as the primary carotenoids. Under low-light conditions, a variant LH2, denoted B800-820, is formed, and rhodopinal and rhodopinal glucoside are the most abundant carotenoids. The present investigation compares and contrasts the spectral properties and dynamics of the excited states of rhodopin and rhodopinal in solution. In addition, the systematic differences in pigment composition and structure of the chromophores in the LH2 complexes provide an opportunity to explore the effect of these factors on the rate and efficiency of carotenoid-to-BChl energy transfer. It is found that the enzymatic conversion of rhodopin to rhodopinal by Rbl. acidophilus 7050 grown under low-light conditions results in nearly 100% carotenoid-to-BChl energy transfer efficiency in the LH2 complex. This comparative analysis provides insight into how photosynthetic systems are able to adapt and survive under challenging environmental conditions.

The relationship between house size and life cycle energy demand: Implications for energy efficiency regulations for buildings

International Nuclear Information System (INIS)

Stephan, André; Crawford, Robert H.

2016-01-01

House size has significantly increased over the recent decades in many countries. Larger houses often have a higher life cycle energy demand due to their increased use of materials and larger area to heat, cool and light. Yet, most energy efficiency regulations for buildings fail to adequately include requirements for addressing the energy demand associated with house size. This study quantifies the effect of house size on life cycle energy demand in order to inform future regulations. It uses a parametric model of a typical detached house in Melbourne, Australia and varies its floor area from 100 to 392 m"2 for four different household sizes. Both initial and recurrent embodied energy requirements are quantified using input-output-based hybrid analysis and operational energy is calculated in primary energy terms over 50 years. Results show that the life cycle energy demand increases at a slower rate compared to house size. Expressing energy efficiency per m"2 therefore favours large houses while these require more energy. Also, embodied energy represents 26–50% across all variations. Building energy efficiency regulations should incorporate embodied energy, correct energy intensity thresholds for house size and use multiple functional units to measure efficiency. These measures may help achieve greater net energy reductions. - Highlights: • The life cycle energy demand (LCE) is calculated for 90 house sizes and 4 household sizes. • The LCE is sublinearly correlated with house size. • Larger houses appear to be more energy efficient per m"2 while they use more energy overall. • Embodied energy (EE) represents up to 52% of the LCE over 50 years. • Building energy efficiency regulations need to consider house size and EE.

Energy Efficiency Resources to Support State Energy Planning

Energy Technology Data Exchange (ETDEWEB)

Office of Strategic Programs, Strategic Priorities and Impact Analysis Team

2017-06-01

An early step for most energy efficiency planning is to identify and quantify energy savings opportunities, and then to understand how to access this potential. The U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy offers resources that can help with both of these steps. This fact sheet presents those resources. The resources are also available on the DOE State and Local Solution Center on the "Energy Efficiency: Savings Opportunities and Benefits" page: https://energy.gov/eere/slsc/energy-efficiency-savings-opportunities-and-benefits.

Conversion of visible light to electrical energy - Stable cadmium selenide photoelectrodes in aqueous electrolytes

Science.gov (United States)

Wrighton, M. S.; Ellis, A. B.; Kaiser, S. W.

1977-01-01

Stabilization of n-type CdSe to photoanodic dissolution is reported. The stabilization is accomplished by the competitive oxidation of S(--) or S(n)(--) at the CdSe photoanode in an electrochemical cell. Such stabilized cells are shown to sustain the conversion of low energy (not less than 1.7 eV) visible light to electricity with good efficiency and no deterioration of the CdSe photoelectrode or of the electrolyte. The electrolyte undergoes no net chemical change because the oxidation occurring at the photoelectrode is reversed at the cathode. Conversion of monochromatic light at 633 nm to electricity is shown to be up to approximately 9% efficient with output potentials of approximately 0.4 V. Conversion of solar energy to electricity is estimated to be approximately 2% efficient.

High-efficiency green phosphorescent organic light-emitting diodes with double-emission layer and thick N-doped electron transport layer

Energy Technology Data Exchange (ETDEWEB)

Nobuki, Shunichiro, E-mail: shunichiro.nobuki.nb@hitachi.com [Hitachi Research Laboratory, Hitachi Ltd., 7-1-1 Omika-cho, Hitachi-city, Ibaraki 319-1292 (Japan); Wakana, Hironori; Ishihara, Shingo [Hitachi Research Laboratory, Hitachi Ltd., 7-1-1 Omika-cho, Hitachi-city, Ibaraki 319-1292 (Japan); Mikami, Akiyoshi [Dept. of Electrical Engineering, Kanazawa Institute of Technology, 7-1 Ohgigaoka, Nonoichimachi, Ishikawa 921-8501 (Japan)

2014-03-03

We have developed green phosphorescent organic light-emitting diodes (OLEDs) with high external quantum efficiency of 59.7% and power efficiency of 243 lm/W at 2.73 V at 0.053 mA/cm{sup 2}. A double emission layer and a thick n-doped electron transport layer were adopted to improve the exciton recombination factor. A high refractive index hemispherical lens was attached to a high refractive index substrate for extracting light trapped inside the substrate and the multiple-layers of OLEDs to air. Additionally, we analyzed an energy loss mechanism to clarify room for the improvement of our OLEDs including the charge balance factor. - Highlights: • We developed high efficiency green phosphorescent organic light-emitting diode (OLED). • Our OLED had external quantum efficiency of 59.7% and power efficiency of 243 lm/W. • A double emission layer and thick n-doped electron transport layer were adopted. • High refractive index media (hemispherical lens and substrate) were also used. • We analyzed an energy loss mechanism to clarify the charge balance factor of our OLED.

Zinc oxide nanostructures and its nano-compounds for efficient visible light photo-catalytic processes

Science.gov (United States)

Adam, Rania E.; Alnoor, Hatim; Elhag, Sami; Nur, Omer; Willander, Magnus

2017-02-01

Zinc oxide (ZnO) in its nanostructure form is a promising material for visible light emission/absorption and utilization in different energy efficient photocatalytic processes. We will first present our recent results on the effect of varying the molar ratio of the synthesis nutrients on visible light emission. Further we will use the optimized conditions from the molar ration experiments to vary the synthesis processing parameters like stirring time etc. and the effect of all these parameters in order to optimize the efficiency and control the emission spectrum are investigated using different complementary techniques. Cathodoluminescence (CL) is combined with photoluminescence (PL) and electroluminescence (EL) as the techniques to investigate and optimizes visible light emission from ZnO/GaN light emitting diodes. We will then show and discuss our recent finding of the use of high quality ZnO nanoparticles (NPs) for efficient photo-degradation of toxic dyes using the visible spectra, namely with a wavelength up to 800 nm. In the end, we show how ZnO nanorods (NRs) are used as the first template to be transferred to bismuth zinc vanadate (BiZn2VO6). The BiZn2VO6 is then used to demonstrate efficient and cost effective hydrogen production through photoelectrochemical water splitting using solar radiation.

DTU International Energy Report 2012: Energy efficiency improvements

DEFF Research Database (Denmark)

Increased energy efficiency can reduce global CO2 emissions over the period to 2050 with up to 25%. On the top of that large profits can be gained for very little investment. Energy efficiency improvements can save investment in new energy infrastructure, cut fuel costs, increase competitiveness...... and increase consumer welfare. Thus, it is natural for DTU International Energy Report 2012 to take up this issue and analyze the global, regional and national challenges in exploiting energy efficiency and promote research and development in energy efficiency....

Highly efficient light management for perovskite solar cells.

Science.gov (United States)

Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

2016-01-06

Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

National energy efficiency programme

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper focusses on energy conservation and specifically on energy efficiency which includes efficiency in the production, delivery and utilisation of energy as part of the total energy system of the economy. A National Energy Efficiency Programme is being launched in the Eighth Plan that will take into account both macro level and policy and planning considerations as well as micro level responses for different category of users in the industry, agriculture, transport and domestic sectors. The need for such a National Energy Efficiency Programme after making an assessment of existing energy conservation activities in the country is discussed. The broad framework and contents of the National Energy Efficiency Programme have been outlined and the Eighth Plan targets for energy conservation and their break-up have been given. These targets, as per the Eighth Plan document are 5000 MW in electricity installed capacity and 6 million tonnes of petroleum products by the terminal year of the Eighth Plan. The issues that need to be examined for each sector for achieving the above targets for energy conservation in the Eighth Plan are discussed briefly. They are: (a) policy and planning, (b) implementation arrangements which include the institutional setup and selective legislation, (c) technological requirements, and (d) resource requirements which include human resources and financial resources. (author)

Efficient white organic light emission by single emitting layer

Energy Technology Data Exchange (ETDEWEB)

Ko, Young Wook; Chung, Choong-Heui; Lee, Jin Ho; Kim, Yong-Hae; Sohn, Choong-Yong; Kim, Bong-Chul; Hwang, Chi-Sun; Song, Yoon-Ho; Lim, Jongtae; Ahn, Young-Joo; Kang, Gi-Wook; Lee, Namheon; Lee, Changhee

2003-02-24

Stable organic white light-emitting diodes are successfully fabricated by a single organic white emitting layer, which is Bis (2-methyl-8-quinolinato) (triphenylsiloxy) aluminum (III) (SAlq) doped red fluorescent dye of 4-(dicyanomethylene)-2-tert-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)- 4H-pyran (DCJTB). The incomplete energy transfer from blue-emitting SAlq to red-emitting DCJTB enables to obtain a stable white balanced light-emission by the DCJTB doping concentration of 0.5%. A device with the structure of ITO/TPD (50 nm)/SAlq:DCJTB (30 nm, 0.5%)/Alq{sub 3} (20 nm)/LiF (0.5 nm)/Al (110 nm) shows maximum luminance of 20 400 cd/m{sup 2} at 810 mA/cm{sup 2}, external quantum efficiency of 2% at 200 cd/m{sup 2} ({approx}3 mA/cm{sup 2}), power efficiency of 2.3 lm/W at 67 cd/m{sup 2} ({approx}1 mA/cm{sup 2}), and a Commission Internationale de l'Eclairage chromaticity coordinates of (0.34, 0.39) at 1.8 mA/cm{sup 2} to (0.31, 0.38) at 36 mA/cm{sup 2}.

Measuring thermo-luminescence efficiency of TLD-2000 detectors to different energy photons

Energy Technology Data Exchange (ETDEWEB)

Xie, Wei Min; Chen, Bao Wei; Han, Yi; Yang, Zhong Jian [China Institute for Radiation Protection, Taiyuan (China)

2016-06-15

As an important detecting device, TLD is a widely used in the radiation monitoring. It is essential for us to study the property of detecting element. The aim of this study is to calculate the thermo-luminescence efficiency of TL elements. A batch of thermo-luminescence elements were irradiated by the filtered X-ray beams of average energies in the range 40-200 kVp, 662 keV {sup 137}Cs gamma rays and then the amounts of lights were measured by the TL reader. The deposition energies in elements were calculated by theory formula and Monte Carlo simulation. The unit absorbed dose in elements by photons with different energies corresponding to the amounts of lights was calculated, which is called the thermo luminescent efficiency (η(E)). Because of the amounts of lights can be calculated by the absorbed dose in elements multiply η(E), the η(E) can be calculated by the experimental data (the amounts of lights) divided by absorbed dose. The deviation of simulation results compared with theoretical calculation results were less than 5%, so the absorbed dose in elements was calculated by simulation results in here. The change range of η(E) value, relative to 662 keV {sup 137}Cs gamma rays, is about 30% in the energy range of 33 keV to 662 keV, is in accordance by the comparison with relevant foreign literatures. The η(E) values can be used for updating the amounts of lights that are got by the direct ratio assumed relations with deposition energy in TL elements, which can largely reduce the error of calculation results of the amounts of lights. These data can be used for the design of individual dosimeter which used TLD-2000 thermo-luminescence elements, also have a certain reference value for manufacturer to improve the energy-response performance of TL elements by formulation adjustment.

Photosynthetic efficiency of Chlamydomonas reinhardtii in flashing light

NARCIS (Netherlands)

Vejrazka, C.; Janssen, M.G.J.; Streefland, M.; Wijffels, R.H.

2011-01-01

Efficient light to biomass conversion in photobioreactors is crucial for economically feasible microalgae production processes. It has been suggested that photosynthesis is enhanced in short light path photobioreactors by mixing-induced flashing light regimes. In this study, photosynthetic

Hybrid bilayer plasmonic metasurface efficiently manipulates visible light

Science.gov (United States)

Qin, Fei; Ding, Lu; Zhang, Lei; Monticone, Francesco; Chum, Chan Choy; Deng, Jie; Mei, Shengtao; Li, Ying; Teng, Jinghua; Hong, Minghui; Zhang, Shuang; Alù, Andrea; Qiu, Cheng-Wei

2016-01-01

Metasurfaces operating in the cross-polarization scheme have shown an interesting degree of control over the wavefront of transmitted light. Nevertheless, their inherently low efficiency in visible light raises certain concerns for practical applications. Without sacrificing the ultrathin flat design, we propose a bilayer plasmonic metasurface operating at visible frequencies, obtained by coupling a nanoantenna-based metasurface with its complementary Babinet-inverted copy. By breaking the radiation symmetry because of the finite, yet small, thickness of the proposed structure and benefitting from properly tailored intra- and interlayer couplings, such coupled bilayer metasurface experimentally yields a conversion efficiency of 17%, significantly larger than that of earlier single-layer designs, as well as an extinction ratio larger than 0 dB, meaning that anomalous refraction dominates the transmission response. Our finding shows that metallic metasurface can counterintuitively manipulate the visible light as efficiently as dielectric metasurface (~20% in conversion efficiency in Lin et al.’s study), although the metal’s ohmic loss is much higher than dielectrics. Our hybrid bilayer design, still being ultrathin (~λ/6), is found to obey generalized Snell’s law even in the presence of strong couplings. It is capable of efficiently manipulating visible light over a broad bandwidth and can be realized with a facile one-step nanofabrication process. PMID:26767195

Far-red light is needed for efficient photochemistry and photosynthesis.

Science.gov (United States)

Zhen, Shuyang; van Iersel, Marc W

2017-02-01

The efficiency of monochromatic light to drive photosynthesis drops rapidly at wavelengths longer than 685nm. The photosynthetic efficiency of these longer wavelengths can be improved by adding shorter wavelength light, a phenomenon known as the Emerson enhancement effect. The reverse effect, the enhancement of photosynthesis under shorter wavelength light by longer wavelengths, however, has not been well studied and is often thought to be insignificant. We quantified the effect of adding far-red light (peak at 735nm) to red/blue or warm-white light on the photosynthetic efficiency of lettuce (Lactuca sativa). Adding far-red light immediately increased quantum yield of photosystem II (Φ PSII ) of lettuce by an average of 6.5 and 3.6% under red/blue and warm-white light, respectively. Similar or greater increases in Φ PSII were observed after 20min of exposure to far-red light. This longer-term effect of far-red light on Φ PSII was accompanied by a reduction in non-photochemical quenching of fluorescence (NPQ), indicating that far-red light reduced the dissipation of absorbed light as heat. The increase in Φ PSII and complementary decrease in NPQ is presumably due to preferential excitation of photosystem I (PSI) by far-red light, which leads to faster re-oxidization of the plastoquinone pool. This facilitates reopening of PSII reaction centers, enabling them to use absorbed photons more efficiently. The increase in Φ PSII by far-red light was associated with an increase in net photosynthesis (P n ). The stimulatory effect of far-red light increased asymptotically with increasing amounts of far-red. Overall, our results show that far-red light can increase the photosynthetic efficiency of shorter wavelength light that over-excites PSII. Copyright © 2016 Elsevier GmbH. All rights reserved.

Miniature photovoltaic energy system for lighting

International Nuclear Information System (INIS)

Awais, M.

1999-01-01

In this project a miniature photovoltaic energy system has been designed and developed, that may be used in remote areas and villages for lighting purposes. System sizing is the important part of the project because it affects the cost of the system. Therefore, first of all system sizing has been done. For conversion of dc voltage of the battery into ac voltage, an inverter has been designed. To charge the battery when the sun is not shining, a standby system has been developed using a bicycle and dynamo. To indicate the battery's state of charge and discharge, a battery monitoring circuit has also been developed. Similarly, to protect the battery from over discharging, a battery protection circuit has been designed. In order to measure how much energy is going from standby system to the battery, an efficient dc electronic energy meter has been designed and developed. The working of the overall system has been tested and found to give good performance. (author)

Efficient and versatile light. LEDs save energy and open up manifold possibilities of design; Effizientes und vielseitiges Licht. LEDs sparen Energie und eroeffnen zahlreiche Designmoeglichkeiten

Energy Technology Data Exchange (ETDEWEB)

Fiebig, Michael [OSRAM Opto Semicondutors GmbH, Muenchen (Germany). Bereich Marketing und Business Development

2010-07-01

Light bulbs leave the European market step by step. These conventional light sources are too inefficient in the private and conventional sector. There are a lot of alternatives to light bulbs. But no technology will be able to save as much energy as light emitting diodes (LED) in the future. Today, these LEDs meet us in most different applications. Continuously new areas of application are opened up in order to reduce the power requirement clearly for the production of artificial light. Apart from energy conservation diodes also enable untold possibilities. In the future, light can be still more flexibly used owing to LED. LEDs are ideal light sources for planners and designers.

Energy efficiency: Separate report to December 31, 1993

International Nuclear Information System (INIS)

1994-01-01

Hydro-Quebec's energy efficiency project puts a priority on energy conservation and improvement of the existing network to satisfy long-term electricity demand. The objective of the project's energy savings program is to save 9.3 TWh by the year 2000, allocated among three sectors. The program is to be carried out in three phases. The first, 1990-1992, corresponds to a sensitization phase, and has had success in terms of commercial impact. The second phase, 1993-1995, is in progress; a third phase to end at the year 2000 will bring adjustments and refinements needed to attain the stated objective. The success of the first two years of the program has contributed to maintaining two performance indicators relating to residential customer satisfaction with regard to energy efficiency activities and the levels of energy savings generated. The project's load management program provides for interventions that will lead to a reduction in peak demand of 3,320 MW by 2000. In the second phase of the program, three programs were launched in 1993 with the objective of saving 3.7 TWh, or 2 TWh in the residential sector, 1.2 TWh in commercial and institutional lighting, and 0.5 TWh in industrial systems. Other programs will be tested in pilot projects in 1994. Programs in the areas of electrotechnologies and residential dual-energy started in 1993 but results are not yet available. To carry out its energy efficiency programs, Hydro-Quebec has entered cooperative agreements with manufacturers, distributors, and vendors, and has developed different forms of collaboration with government agencies and institutions. The proposed energy efficiency programs will sustain nearly 38,000 person-years of employment in Quebec from now to 2000. 10 tabs

Energy-efficient technologies and policies can help us win the race to save the planet

International Nuclear Information System (INIS)

Rosenfeld, A.H.; Price, L.

1994-01-01

Past achievements in energy efficiency in the residential sector are reviewed and policy mechanisms for continuing such savings are discussed. Between 1973 and 1985, the efficiency of most new individual energy-using products doubled, and this occurred with minimal investments; the price difference between the existing and the more efficient product was typically recovered through reduced energy bills in three years or less. This is illustrated with examples including automobiles, refrigerators, windows, and lighting. With the recent decline in oil prices, energy use per unit of gross national product in the USA has risen slightly and high energy prices no longer provide the main motivation for further energy efficiency improvements. Other considerations that promote energy efficiency include the economic growth that results from using energy efficient products, environmental protection, and the need to reduce greenhouse gas emissions. Further energy efficiency improvements can be made using effective policies, such as establishment of energy-use labels for appliances and equipment, imposing energy efficiency standards, providing incentives for appliance and equipment manufacturers to produce energy efficient products, using fees and rebates to reduce energy use, building automobile insurance costs into gasoline prices, integrated resource planning and demand side management by energy utilities, and mortgage rates based on energy efficiency and conservation considerations. 42 refs., 6 figs., 2 tabs

Thin Film Packaging Solutions for High Efficiency OLED Lighting Products

Energy Technology Data Exchange (ETDEWEB)

None

2008-06-30

The objective of the 'Thin Film Packaging Solutions for High Efficiency OLED Lighting Products' project is to demonstrate thin film packaging solutions based on SiC hermetic coatings that, when applied to glass and plastic substrates, support OLED lighting devices by providing longer life with greater efficiency at lower cost than is currently available. Phase I Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on optical glass with lifetime of 1,000 hour life, CRI greater than 75, and 15 lm/W. Phase II Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on plastic or glass composite with 25 lm/W, 5,000 hours life, and CRI greater than 80. Phase III Objective: Demonstrate 2 x 2 ft{sup 2} thin film encapsulated working phosphorescent OLED with 40 lm/W, 10,000 hour life, and CRI greater than 85. This report details the efforts of Phase III (Budget Period Three), a fourteen month collaborative effort that focused on optimization of high-efficiency phosphorescent OLED devices and thin-film encapsulation of said devices. The report further details the conclusions and recommendations of the project team that have foundation in all three budget periods for the program. During the conduct of the Thin Film Packaging Solutions for High Efficiency OLED Lighting Products program, including budget period three, the project team completed and delivered the following achievements: (1) a three-year marketing effort that characterized the near-term and longer-term OLED market, identified customer and consumer lighting needs, and suggested prototype product concepts and niche OLED applications lighting that will give rise to broader market acceptance as a source for wide area illumination and energy conservation; (2) a thin film encapsulation technology with a lifetime of nearly 15,000 hours, tested by calcium coupons, while stored at 16 C and 40% relative humidity ('RH'). This encapsulation technology

Light Ion Beams for Energy Production in ADS

Directory of Open Access Journals (Sweden)

Paraipan Mihaela

2018-01-01

Full Text Available A comparative study of the energy efficiency of proton beams with an energy from 0.5 GeV to 4 GeV and light ion beams (7Li, 9Be, 11B, and 12C with energies from 0.25 AGeV to 1 AGeV in natural and enriched quasi-infinite U target is presented. The numerical results on the particle transport and interaction are obtained using the code Geant4. The following target optimization issues are addressed: the beam window dimensions, and the possibility to use a core from low Z materials. The best solution for ADS from the point of view of the energy gain and miniaturization is obtained for 7Li or 9Be beam with an energy of 0.3–0.4 AGeV and a target with Be core.

Data mining application in industrial energy audit for lighting

Energy Technology Data Exchange (ETDEWEB)

Maricar, N.M.; Kim, G.C.; Jamal, N. [Kolej Univ., Melaka (Malaysia). Faculty of Electrical Engineering

2005-07-01

A data mining application for lighting energy audits at industrial sites was presented. Data collection was based on the parameters needed for the analysis part of the audit. Data collection included the activity for which the room was used; its dimension; light level readings in lux; the number of luminaries; the number of lamps per luminaries; lamp fixtures; and lamp wattage. The lumen method was used to calculate the recommended numbers of luminaries in the room. The number was then compared with the existing system's luminaries. The installed load efficacy ratio (ILER) was then used to determine proper retrofit action to maximize energy usage. The difference between the calculated lux and the standard lux was used to create data subsets. A data mining algorithm was used to determine that the ILER plays an important role in calculating the efficiency of lighting systems. It was also concluded that the method can be used to minimize the time needed to analyze large amounts of lighting data. The results of case studies were also used to show that the combined data mining algorithm provided accurate assessments using existing calculated data. 7 refs., 8 tabs., 5 figs.

Lighting.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1992-09-01

Since lighting accounts for about one-third of the energy used in commercial buildings, there is opportunity to conserve. There are two ways to reduce lighting energy use: modify lighting systems so that they used less electricity and/or reduce the number of hours the lights are used. This booklet presents a number of ways to do both. Topics covered include: reassessing lighting levels, reducing lighting levels, increasing bulb & fixture efficiency, using controls to regulate lighting, and taking advantage of daylight.

Efficiency of energy recovery from waste incineration, in the light of the new Waste Framework Directive.

Science.gov (United States)

Grosso, Mario; Motta, Astrid; Rigamonti, Lucia

2010-07-01

This paper deals with a key issue related to municipal waste incineration, which is the efficiency of energy recovery. A strong driver for improving the energy performances of waste-to-energy plants is the recent Waste Framework Directive (Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on waste and repealing certain Directives), which allows high efficiency installations to benefit from a status of "recovery" rather than "disposal". The change in designation means a step up in the waste hierarchy, where the lowest level of priority is now restricted to landfilling and low efficiency wastes incineration. The so-called "R1 formula" reported in the Directive, which counts for both production of power and heat, is critically analyzed and correlated to the more scientific-based approach of exergy efficiency. The results obtained for waste-to-energy plants currently operating in Europe reveal some significant differences in their performance, mainly related to the average size and to the availability of a heat market (district heating). Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Energy efficiency and behaviour

DEFF Research Database (Denmark)

Carstensen, Trine Agervig; Kunnasvirta, Annika; Kiviluoto, Katariina

separate key aspects hinders strategic energy efficiency planning. For this reason, the PLEEC project – “Planning for Energy Efficient Cities” – funded by the EU Seventh Framework Programme uses an integrative approach to achieve the sus‐ tainable, energy– efficient, smart city. By coordinating strategies...... to conduct behavioural interventions, to be presented in Deliverable 5.5., the final report. This report will also provide valuable information for the WP6 general model for an Energy-Smart City. Altogether 38 behavioural interventions are analysed in this report. Each collected and analysed case study...... of the European Union’s 20‐20‐20 plan is to improve energy efficiency by 20% in 2020. However, holistic knowledge about energy efficiency potentials in cities is far from complete. Currently, a WP4 location in PLEEC project page 3 variety of individual strategies and approaches by different stakeholders tackling...

Using interlayer step-wise triplet transfer to achieve an efficient white organic light-emitting diode with high color-stability

Energy Technology Data Exchange (ETDEWEB)

Wang, Qi [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Department of Electrical Engineering and Computer Sciences, College of Engineering, South Dakota State University, Brookings, South Dakota 57007 (United States); Ma, Dongge, E-mail: mdg1014@ciac.jl.cn; Ding, Junqiao; Wang, Lixiang [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Leo, Karl [Tech. Univ. Dresden, Inst. Angew. Photophys., D-01062 Dresden (Germany); Qiao, Qiquan [Department of Electrical Engineering and Computer Sciences, College of Engineering, South Dakota State University, Brookings, South Dakota 57007 (United States); Jia, Huiping; Gnade, Bruce E. [Department of Materials Science and Engineering and Erik Jonsson School of Engineering and Computer Science, University of Texas at Dallas, Richardson, Texas 75083 (United States)

2014-05-12

An efficient phosphorescent white organic light emitting-diode with a red-green-blue tri-emitting-layer structure is reported. The host of the red dopant possesses a lower triplet-energy than the green dye. An interlayer step-wise triplet transfer via blue dye → green dye → red host → red dye is achieved. This mechanism allows an efficient triplet harvesting by the three dopants, thus maintaining a balanced white light and reducing energy loss. Moreover, the color stability of the device is improved significantly. The white device not only achieves a peak external quantum efficiency of 21.1 ± 0.8% and power efficiency of 37.5 ± 1.4 lm/W but shows no color shift over a wide range of voltages.

Lighting and cooling energy consumption in an open-plan office using solar film coating

International Nuclear Information System (INIS)

Li, Danny H.W.; Lam, Tony N.T.; Wong, S.L.; Tsang, Ernest K.W.

2008-01-01

In subtropical Hong Kong, solar heat gain via glazing contributes to a significant proportion of the building envelope cooling load. The principal fenestration design includes eliminating direct sunlight and reducing cooling requirements. Daylighting is an effective approach to allow a flexible building facade design strategy, and to enhance an energy-efficient and green building development. This paper studies the lighting and cooling energy performances for a fully air-conditioned open-plan office when solar control films together with daylight-linked lighting controls are being used. Measurements were undertaken at two stages including the electricity expenditures for the office using photoelectric dimming controls only (first stage) and together with the solar control film coatings on the windows (second stage). Electric lighting and cooling energy consumption, transmitted daylight illuminance and solar radiation were systematically recorded and analysed. The measured data were also used for conducting and validating the building energy simulations. The findings showed that the solar film coatings coupled with lighting dimming controls cut down 21.2% electric lighting and 6.9% cooling energy consumption for the open-plan office

Comparative study of energy-efficiency and conservation systems for ceramic metal-halide discharge lamps

International Nuclear Information System (INIS)

Hermoso Orzáez, Manuel Jesús; Andrés Díaz, José Ramón de

2013-01-01

Interest in energy savings in urban lighting is gaining traction and has become a priority for municipal administrations. LED (light-emitting diode) technology appears to be the clear future lighting choice. However, this technology is still rapidly developing and has not been sufficiently tested. As an intermediate step, alternative proposals for energy-saving equipment for traditional discharge lamps are desirable so that the current technologies can coexist with the new LED counterparts for the short and medium term. This article provides a comparative study between two efficiency and energy-saving systems for discharge lamps with metal-halide and ceramic technologies, i.e., a lighting flow dimmer-stabilizer and a double-level electronic ballast. - Highlights: ► It has been demonstrated the possibility of regulating ceramic metal-halide lamps with lighting flow dimmer-stabilizer. ► Electronic ballasts can save approximately double quantity of energy than lighting flow dimmer-stabilizers. ► The use of lighting flow dimmer-stabilizer is more profitable than electronic ballasts due to costs and reliability

How to prevent greenhouse gas emissions in electrical installations: lighting energy savings and solar energy approaches

Energy Technology Data Exchange (ETDEWEB)

Yavuz, C.; Aksoy, C. [Sakarya University, Faculty of Engineering, Electrical and Electronics Engineering Department, Serdivan (Turkey)

2012-07-01

Day by day greenhouse gas emissions increase dramatically. A passive adaptive method of lighting energy savings, daylight responsive systems are considered one of the best solutions for energy efficiency, saving and prevent CO{sub 2} emissions. Results of an annual experiment which was held in Sakarya University proves the necessity of daylight responsive systems with a 41% energy saving and 942.5 kg of prevented CO{sub 2} emissions Thinking this prevention is realized just only in a 36 m{sup 2} room with the use of 8 luminaries spreading such systems to nationwide, a major amount of greenhouse gas emissions would be prohibited. On the other hand energy saving is not the only way to reduce CO{sub 2} emissions. Again in Sakarya University a project has started to investigate the possibility of illumination of a complete building by using solar energy. This paper evaluates these mentioned systems both in energy efficiency, greenhouse gas emissions prevention and economic point of views. (author)

Efficient and bright organic light-emitting diodes on single-layer graphene electrodes

Science.gov (United States)

Li, Ning; Oida, Satoshi; Tulevski, George S.; Han, Shu-Jen; Hannon, James B.; Sadana, Devendra K.; Chen, Tze-Chiang

2013-08-01

Organic light-emitting diodes are emerging as leading technologies for both high quality display and lighting. However, the transparent conductive electrode used in the current organic light-emitting diode technologies increases the overall cost and has limited bendability for future flexible applications. Here we use single-layer graphene as an alternative flexible transparent conductor, yielding white organic light-emitting diodes with brightness and efficiency sufficient for general lighting. The performance improvement is attributed to the device structure, which allows direct hole injection from the single-layer graphene anode into the light-emitting layers, reducing carrier trapping induced efficiency roll-off. By employing a light out-coupling structure, phosphorescent green organic light-emitting diodes exhibit external quantum efficiency >60%, while phosphorescent white organic light-emitting diodes exhibit external quantum efficiency >45% at 10,000 cd m-2 with colour rendering index of 85. The power efficiency of white organic light-emitting diodes reaches 80 lm W-1 at 3,000 cd m-2, comparable to the most efficient lighting technologies.

Energy efficiency: Lever for the Energy Transition

International Nuclear Information System (INIS)

2012-12-01

The Eco-electric industry group (FFIE, FGME, Gimelec, IGNES, SERCE) has conducted a study to evaluate the energy saving potential of active energy efficiency solutions in the residential and commercial building sectors. Based on field implementations and demonstrators, it has been demonstrated that active energy efficiency can sustainably achieve substantial savings for households, companies and public authorities. Energy Efficiency - Lever for the energy transition presents the results and conclusions of that study, alongside with recommendations for public authority in terms of building retrofit policy for putting France on the best possible 'trajectory' from a budgetary and environmental point of view. (author)

Energy technologies and energy efficiency in economic modelling