Using the private finance initiative for energy efficiency projects at the urban scale

2016 ◽  
Vol 10 (1) ◽  
pp. 99-117 ◽  
Author(s):  
Alberto De Marco ◽  
Giulio Mangano ◽  
Fania Valeria Michelucci ◽  
Giovanni Zenezini
Keyword(s):  
Energy Efficiency ◽  
Urban Areas ◽  
Light Emitting Diode ◽  
Project Finance ◽  
Private Finance Initiative ◽  
Content Type ◽  
Light Emitting ◽  
Alternate Forms ◽  
Private Investors

Purpose – The purpose of this paper is to suggest the usage of the project finance (PF) scheme as a suitable mechanism to fund energy efficiency projects at the urban scale and present its advantages and adoption barriers. Design/methodology/approach – A case study is developed to renew the traffic lighting system of an Italian town via replacement of the old lamps with new light-emitting diode (LED) technology. Several partners are involved in the case project to construct a viable PF arrangement. Findings – The case study presents the viability of the proposed PF scheme that provides for acceptable financial returns and bankability. However, it also shows that the need for short concession periods may call for a public contribution to the initial funding to make the project more attractive to private investors. Practical implications – This case study is a useful guideline for governments and promoters to using the PF arrangement to fund energy efficiency investments in urban settings. It helps designing an appropriate PF scheme and understanding the advantages of PF to reduce risk and, consequently, increase the debt leverage and profitability of energy efficiency projects. Originality/value – This paper contributes to bridging the gap about the lack of works addressing the implementation of the PF mechanism in the energy efficiency sector in urban areas. The importance of this paper is also associated with the shortage of traditional public finance faced by many cities that forces to seek for alternate forms of financing.

Temperature and Humidity Dependent Reliability Analysis of RGB LED Chips

2006 ◽  
Author(s):  
Jun-Xian Fu ◽  
Shukri Souri ◽  
James S. Harris
Keyword(s):  
Reliability Analysis ◽  
Printed Circuit Board ◽  
Light Emitting Diode ◽  
Circuit Board ◽  
Light Emitting ◽  
Printed Circuit ◽  
Root Cause ◽  
Micro Cracks ◽  
Temperature And Humidity

Abstract Temperature and humidity dependent reliability analysis was performed based on a case study involving an indicator printed-circuit board with surface-mounted multiple-die red, green and blue light-emitting diode chips. Reported intermittent failures were investigated and the root cause was attributed to a non-optimized reflow process that resulted in micro-cracks and delaminations within the molding resin of the chips.

scholarly journals Increased Plant Quality, Greenhouse Productivity and Energy Efficiency with Broad-Spectrum LED Systems: A Case Study for Thyme (Thymus vulgaris L.)

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 960
Author(s):  
Jenny Manuela Tabbert ◽  
Hartwig Schulz ◽  
Andrea Krähmer
Keyword(s):  
Broad Spectrum ◽  
Energy Savings ◽  
Light Emitting Diode ◽  
Thymus Vulgaris ◽  
Light Spectrum ◽  
Light Emitting ◽  
Biomass Yields ◽  
Lighting Systems

A light-emitting diode (LED) system covering plant-receptive wavebands from ultraviolet to far-red radiation (360 to 760 nm, “white” light spectrum) was investigated for greenhouse productions of Thymus vulgaris L. Biomass yields and amounts of terpenoids were examined, and the lights’ productivity and electrical efficiency were determined. All results were compared to two conventionally used light fixture types (high-pressure sodium lamps (HPS) and fluorescent lights (FL)) under naturally low irradiation conditions during fall and winter in Berlin, Germany. Under LED, development of Thymus vulgaris L. was highly accelerated resulting in distinct fresh yield increases per square meter by 43% and 82.4% compared to HPS and FL, respectively. Dry yields per square meter also increased by 43.1% and 88.6% under LED compared to the HPS and FL lighting systems. While composition of terpenoids remained unaffected, their quantity per gram of leaf dry matter significantly increased under LED and HPS as compared to FL. Further, the power consumption calculations revealed energy savings of 31.3% and 20.1% for LED and FL, respectively, compared to HPS. In conclusion, the implementation of a broad-spectrum LED system has tremendous potential for increasing quantity and quality of Thymus vulgaris L. during naturally insufficient light conditions while significantly reducing energy consumption.

A method for energy efficiency assessment during urban energy planning

2014 ◽  
Vol 3 (2) ◽  
pp. 132-152 ◽  
Author(s):  
Karin Regina de Casas Castro Marins
Keyword(s):  
Energy Efficiency ◽  
Urban Areas ◽  
Energy Use ◽  
Energy Performance ◽  
Urban Morphology ◽  
Pollutant Emissions ◽  
Energy Planning ◽  
Bottom Up ◽  
Content Type ◽  
Urban Energy

Purpose – Energy use in urban areas has turned a subject of local and worldwide interest over the last few years, especially emphasized by the correlated greenhouse gases emissions. The purpose of this paper is to analyse the overall energy efficiency potential and emissions resulting from integrated solutions in urban energy planning, in the scale of districts and neighbourhoods in Brazil. Design/methodology/approach – The approach is based on the description and the application of a method to analyse energy performance of urban areas and support their planning. It is a quantitative bottom-up method and involves urban morphology, urban mobility, buildings and energy supply systems. Procedures are applied to the case study of Agua Branca urban development area, located in Sao Paulo, Brazil. Findings – In the case of Agua Branca area, energy efficiency measures in buildings have shown to be very important mostly for the buildings economies themselves. For the area as a whole, strategies in promoting public transport are more effective in terms of energy efficiency and also to decrease pollutant emissions. Originality/value – Literature review has shown there is a lack of approaches and procedures able to support urban energy planning at a community scale. The bottom-up method presented in this paper integrates a plenty of disaggregated and multisectoral parameters at the same stage in urban planning and shows that is possible to identify the most promising actions by building overall performance indexes.

N-face GaN substrate roughening for improved performance GaN-on-GaN LED

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ezzah Azimah Alias ◽  
Muhammad Esmed Alif Samsudin ◽  
Steven DenBaars ◽  
James Speck ◽  
Shuji Nakamura ◽  
...  
Keyword(s):  
Quantum Efficiency ◽  
External Quantum Efficiency ◽  
Light Emitting Diode ◽  
Optical Power ◽  
Ammonium Hydroxide ◽  
Content Type ◽  
Light Emitting ◽  
Gan Led ◽  
Improved Performance ◽  
Substrate Roughening

Purpose This study aims to focus on roughening N-face (backside) GaN substrate prior to GaN-on-GaN light-emitting diode (LED) growth as an attempt to improve the LED performance. Design/methodology/approach The N-face of GaN substrate was roughened by three different etchants; ammonium hydroxide (NH4OH), a mixture of NH4OH and H2O2 (NH4OH: H2O2) and potassium hydroxide (KOH). Hexagonal pyramids were successfully formed on the surface when the substrate was subjected to the etching in all cases. Findings Under 30 min of etching, the highest density of pyramids was obtained by NH4OH: H2O2 etching, which was 5 × 109 cm–2. The density by KOH and NH4OH etchings was 3.6 × 109 and 5 × 108 cm–2, respectively. At standard operation of current density at 20 A/cm2, the optical power and external quantum efficiency of the LED on the roughened GaN substrate by NH4OH: H2O2 were 12.3 mW and 22%, respectively, which are higher than its counterparts. Originality/value This study demonstrated NH4OH: H2O2 is a new etchant for roughening the N-face GaN substrate. The results showed that such etchant increased the density of the pyramids on the N-face GaN substrate, which subsequently resulted in higher optical power and external quantum efficiency to the LED as compared to KOH and NH4OH.

A methodology for identifying critical factors influencing land value in urban areas: a case study of Kerala, India

2020 ◽  
Vol 38 (5) ◽  
pp. 665-681
Author(s):  
Binoy BV ◽  
Naseer MA ◽  
Anil Kumar PP
Keyword(s):  
Expert Opinion ◽  
Urban Areas ◽  
Environmental Planning ◽  
Delphi Survey ◽  
Land Value ◽  
Critical Factors ◽  
Content Type ◽  
Factors Influencing ◽  
Importance Index

PurposeLand value is a measure of the specific features of a property, excluding buildings and other developments. Land value varies depending on the economic, geographic and political aspects of a particular location. The primary purpose of the paper is to identify the general and location-specific attributes impacting property prices in urban Kerala.Design/methodology/approachThe objective of the current study was achieved through a three-cycle Delphi survey and relative importance index (RII) approach. The experts who aided in the survey had a mutual interest in the subject but came from different backgrounds like property valuation, real estate, urban and environmental planning. The initial group of variables identified from the literature was expanded and scrutinized in the first cycle of the Delphi survey. The variables were grouped into five major categories and 13 subcategories based on the literature and expert opinion. In the subsequent stages, the short-listed variables were rated on a seven-point Likert scale until a consensus was attained. The top-ranked variables were identified through the RII method as the critical factors influencing land value in urban Kerala.FindingsThe results indicate that road accessibility and proximity to nuisance sources are the most crucial parameters. The outcome of the study will provide a better understanding of the dynamics of land value and the influencing factors in urban areas.Originality/valuePrevious studies do not give much consideration for the location-specific variability on the influencing parameters. Property management research has not considered the usage of expert opinion and RII for variable selection.

scholarly journals Antibacterial Mechanism of 405-Nanometer Light-Emitting Diode against Salmonella at Refrigeration Temperature

2016 ◽  
Vol 83 (5) ◽  
Author(s):  
Min-Jeong Kim ◽  
Hyun-Gyun Yuk
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Light Emitting Diode ◽  
Dna Oxidation ◽  
Uptake System ◽  
Antibacterial Mechanism ◽  
Content Type ◽  
Light Emitting ◽  
Expression Levels ◽  
Gene Expression Levels

ABSTRACT The aim of this study was to elucidate the antibacterial mechanism of 405 ± 5-nm light-emitting diode (LED) illumination against Salmonella at 4°C in phosphate-buffered saline (PBS) by determining endogenous coproporphyrin content, DNA oxidation, damage to membrane function, and morphological change. Gene expression levels, including of oxyR, recA, rpoS, sodA, and soxR, were also examined to understand the response of Salmonella to LED illumination. The results showed that Salmonella strains responded differently to LED illumination, revealing that S. enterica serovar Enteritidis (ATCC 13076) and S. enterica subsp. enterica serovar Saintpaul (ATCC 9712) were more susceptible and resistant, respectively, than the 16 other strains tested. There was no difference in the amounts of endogenous coproporphyrin in the two strains. Compared with that in nonilluminated cells, the DNA oxidation levels in illuminated cells increased. In illuminated cells, we observed a loss of efflux pump activity, damage to the glucose uptake system, and changes in membrane potential and integrity. Transmission electron microscopy revealed a disorganization of chromosomes and ribosomes due to LED illumination. The levels of the five genes measured in the nonilluminated and illuminated S. Saintpaul cells were upregulated in PBS at a set temperature of 4°C, indicating that increased gene expression levels might be due to a temperature shift and nutrient deficiency rather than to LED illumination. In contrast, only oxyR in S. Enteritidis cells was upregulated. Thus, different sensitivities of the two strains to LED illumination were attributed to differences in gene regulation. IMPORTANCE Bacterial inactivation using visible light has recently received attention as a safe and environmentally friendly technology, in contrast with UV light, which has detrimental effects on human health and the environment. This study was designed to understand how 405 ± 5-nm light-emitting diode (LED) illumination kills Salmonella strains at refrigeration temperature. The data clearly demonstrated that the effectiveness of LED illumination on Salmonella strains depended highly on the serotype and strain. Our findings also revealed that its antibacterial mechanism was mainly attributed to DNA oxidation and a loss of membrane functions rather than membrane lipid peroxidation, which has been proposed by other researchers who studied the antibacterial effect of LED illumination by adding exogenous photosensitizers, such as chlorophyllin and hypericin. Therefore, this study suggests that the detailed antibacterial mechanisms of 405-nm LED illumination without additional photosensitizers may differ from that by exogenous photosensitizers. Furthermore, a change in stress-related gene regulation may alter the susceptibility of Salmonella cells to LED illumination at refrigeration temperature. Thus, our study provides new insights into the antibacterial mechanism of 405 ± 5-nm LED illumination on Salmonella cells.

Using energy profiles to identify university energy reduction opportunities

2016 ◽  
Vol 17 (2) ◽  
pp. 188-207 ◽  
Author(s):  
Nandarani Maistry ◽  
Harold Annegarn
Keyword(s):  
South Africa ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Quantitative Research ◽  
Electricity Consumption ◽  
Working Hours ◽  
Content Type ◽  
Academic Calendar ◽  
The University

Purpose – The purpose of this paper is to outline efforts at the University of Johannesburg, a large metropolitan university in Gauteng province, to examine energy efficiency within the context of the green campus movement, through the analysis of electricity consumption patterns. The study is particularly relevant in light of the cumulative 230 per cent increase in electricity costs between 2008 and 2014 in South Africa that has forced institutions of higher education to seek ways to reduce energy consumption. Design/Methodology/Approach – A quantitative research design was adopted for the analysis of municipal electricity consumption records using a case study approach to identify trends and patterns in consumption. The largest campus of the University of Johannesburg, which is currently one of the largest residential universities in South Africa, was selected as a case study. Average diurnal consumption profiles were plotted according to phases of the academic calendar, distinguished by specific periods of active teaching and research (in-session); study breaks, examinations and administration (out-of-session); and recesses. Average profiles per phase of the academic calendar were constructed from the hourly electricity consumption and power records using ExcelTM pivot tables and charts. Findings – It was found that the academic calendar has profound effects on energy consumption by controlling the level of activity. Diurnal maximum consumption corresponds to core working hours, peaking at an average of 2,500 kWh during “in-session” periods, 2,250 kWh during “out-of-session” periods and 2,100 kWh during recess. A high base load was evident throughout the year (between 1,300 and 1,650 kWh), mainly attributed to heating and cooling. By switching off the 350 kW chiller plant on weekdays, a 9 per cent electricity reduction could be achieved during out-of-session and recess periods. Similarly, during in-session periods, a 6 per cent reduction could be achieved. Practical implications – Key strategies and recommendations are presented to stimulate energy efficiency implementation within the institution. Originality Value – Coding of consumption profiles against the academic calendar has not been previously done in relation to an academic institution. The profiles were used to establish the influence of the academic calendar on electricity consumption, which along with our own observation were used to identify specific consumption reduction opportunities worth pursuing.

Identifying risks and mitigation strategies in private sector participation (PSP) in power generation projects in Ghana

2017 ◽  
Vol 15 (2) ◽  
pp. 153-169 ◽  
Author(s):  
Collins Ameyaw ◽  
Hans Wilhelm Alfen
Keyword(s):  
Power Generation ◽  
Private Sector ◽  
Management Strategies ◽  
Case Study Research ◽  
Mitigation Strategies ◽  
Content Type ◽  
Private Sector Participation ◽  
Risk Management Strategies ◽  
Private Investors

Purpose The purpose of this paper is to identify the risks associated with private sector participation (PSP) in power generation (PG) projects, how they were allocated and the strategies used to mitigate their likely adverse effects. Design/methodology/approach The paper adopts case study research method and cross-case analyses to unearth the key risks and the contractual instruments used to manage them. Findings The paper identified 30 risk factors associated with four major private sector PG projects in Ghana. The allocation and mitigation strategies of these risks are also reported. Originality/value This is the first study to create a risk register of PSP PG projects. Private investors and government have been provided with a comprehensive list of risks associated with PG infrastructure. Would-be investors have also been armed with some potential risk management strategies for proper project structuring.

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