Search results

The recent surge in light emitting diode (LED) lighting retrofitted into schools in the UK is as a result of the UK Government’s 2050 zero carbon pledge. However, the benefits and consequences of LED retrofit projects for staff and enablers and stakeholder knowledge gaps about LED lighting retrofitting have not been fully explored. The aim of this research is to determine the amount of savings in cost, carbon reduction and kilowatt usage and to confirm if repayment from energy and cost savings derived from LED retrofit school projects funded through the SALIX funding option in the UK would be enough to service the loan. Thus, it examines monetary and non-monetary benefits, internal project stakeholder knowledge gaps and the consequences of LED retrofit for the staff and enablers of a large community college in the UK which is funded through the SALIX funding option.

The methodology relied on a hybrid research approach of a case secondary school through the review of literature, analysis of secondary data, focus group and questionnaire survey. The focus group consists of six key project stakeholders. The secondary data was sourced from the Project IGP [Individual Grade Proposal] and the Positive Energy Report from Zenergi, and the closed online questionnaire survey was used to sample 150 teaching staff and school enablers.

The findings show that stakeholders lack project knowledge, trust and expertise/project comprehension. This is in terms of baseline information, LED technology/management, payback modalities, management of risks and ethical issues around environmental impact. The forecasted SALIX savings were not achieved in real-time, partly because it does not take into consideration the increase in energy costs over the payback period. However, the LED retrofit creates efficiencies; drives down energy costs and energy usage; and drives carbon reduction, helping pupils’ learning, improving productivity and performance, and finally leading to a better lighting environment for the school community.

The study will help schools in the UK that intend to access SALIX finance for LED retrofits to understand the challenges and mitigate the risks. It will also help the government to understand the importance of adjusting the payback modalities to the base price when the retrofit was carried out for real-time savings to be made. The research would be useful in ensuring the proactive involvement of all the identified stakeholders in understanding the challenges and what the function entails.

Office buildings confront with the issue of high energy demand during the day time mainly due to heavy use of energy for HVAC and lighting systems. Demand-side energy retrofits (DSER) are identified as effective in controlling electricity demand of existing buildings. The purpose of this paper is to analyse the potential of incorporating DSER in to existing office buildings. The paper reports the cost benefits of using DSER in existing office buildings. Furthermore, it reveals several enablers that can be used to promote retrofits in office buildings of Sri Lanka.

An industry survey was conducted by selecting a sample of 35 office buildings to study the usage of DSER in office buildings of Sri Lanka. Furthermore, three case studies were conducted to analyse the costs benefits of widely used DSER techniques in office buildings.

Research revealed that the use of DSER techniques in existing office buildings of Sri Lanka is at a lower level. However, it found that the financial viability of those DSER was at a promising level. Furthermore, 11 enablers in two levels as organisational level and national level were identified to enhance the use of DSER.

The study justifies the potential of DSER in reducing energy demand of existing office buildings through in-depth cost benefit analysis, which is useful for a country like Sri Lanka which faces massive energy crisis. This encourages Facility Managers towards using DSER to reduce building energy demand. Furthermore, study provides enablers at organisational and national levels to enhance the use of DSER.

Energy-efficient retrofitting of existing buildings is an inexpensive way of reducing energy consumption and mitigating climate change impacts. The purpose of this study is to examine electricity savings and carbon dioxide (CO₂) emission reduction potentials of energy-efficient retrofit measures for surveyed two large shopping malls in India.

A techno-economic model was developed to estimate the electricity savings achieved due to energy-efficient retrofit measures in shopping malls that were surveyed in 2017. Alternative scenarios were constructed based on capital cost and cost of conserved energy (CCE) value for retrofit measures: cheapest replacement, best available technology and best value for money. The life-cycle electricity and CO₂ emission savings and payback period for end-use retrofit measures were evaluated.

The estimated average electricity savings were around 39–56% for various retrofit measures across all three scenarios while the average CO₂ emission reductions were around 50–125 kt-CO₂. Retrofits to light-emitting diode lights and air conditioners with inverter technology offered more life-cycle electricity savings. Paybacks for most lighting end-use measures were estimated to be within 1.5 years while for most space conditioning end-use measures were between 1 and 4 years.

The primary survey-based comprehensive research makes an exclusive contribution by estimating life-cycle electricity savings and CO₂ emission reductions for energy-efficient retrofit measures of lighting and space cooling end-use appliances for existing shopping malls. The present research methodology can also be deployed in other types of commercial buildings and in residential buildings to estimate electricity savings from energy-efficient retrofit measures.

Good illumination creates an aesthetic environment that may positively influence patients’ well-being and provide comfort to the hospital staff. This study aims to focus on exploring the energy efficiency of lighting and subjective perception of the lit environment in a hospital ward to assess quality indicators of ambient lighting conditions.

The existing conventional tubular fluorescent lamp–based lighting system in the surveyed patients’ ward was retrofitted with light-emitting diode (LED) luminaires to explore illumination and energy parameters. Thereafter, a software lighting model was created, simulated and analyzed. A Web-based survey with five bipolar adjective pairs in a semantic differential scale was conducted with 48 participants to record and analyze their subjective responses pertaining to the variations in lamp types and surface reflectance combinations.

The findings imply that the LED tubular lamp–based illumination was deemed more adequate compared to other lamp types and the effects of variations in room surface reflectance combinations on the participants’ responses were statistically significant at α = 0.05 level. The simulated horizontal work plane average illuminance level varied from 131 to 171 lx, mean room surface exitance (MRSE) levels remained between 30 and 90 lm/m² and overall uniformity of illuminance remained between 0.5 and 0.7.

In a hospital ward illuminated by LED tubular lamps, variations in room surface reflectance combinations for a constant luminous flux package output from the lamps may affect the subjective perception of users and the correlation between horizontal work plane average illuminance and MRSE is found to be highly linear (coefficient of determination > 0.97).

The purpose of this paper is to explain why product-centric manufacturers utilize advanced services not as vehicles of transformation, but of reinforcement, to strengthen their established business model logic based on selling products and basic product-related services.

The empirical basis of this study relies on an in-depth case study of a globally operating manufacturer of industrial pumps and related services. The data includes 31 interviews conducted over several years of in-depth collaboration with the studied firm.

Product-centric manufacturers utilize advanced services as engagement platforms to facilitate the external and internal engagement of the actors and the resources controlled by them. Externally, advanced services facilitate access to customer decision makers and insights into their latent needs. Internally, advanced services help the manufacturer to more effectively leverage resources that reside within its different organizational units. Ultimately, in leveraging advanced services as engagement platforms, the manufacturer seeks to boost activities with the greatest immediate impact on its market performance: the sale of products and basic product-related services.

The study explains why managers should invest into development of advanced services even if such services contribute only marginally to the manufacturer’s direct revenues and profits.

This study contributes to development of an alternative explanation of servitization that departs from the current paradigmatic assumptions in the field.

The purpose of this study was to design a renovation plan for a university campus building (Department of Electrical and Computer Engineering) with the aim to achieve nearly zero energy performance, ensuring a low specific demand (lower than 44 kWh/m²) and a high level of on-site renewable generation (equivalent to more than 20 per cent of the energy demand).

The baseline demand was characterized based on energy audits, on smart metering data and on the existing building management system data, showing a recent reduction of the electricity demand owing to some implemented measures. The renovation plan was then designed with two main measures, the total replacement of the actual lighting by LEDs and the installation of a photovoltaic system (PV) with 78.8 kWp coupled with an energy storage system with 100 kWh of lithium-ion batteries.

The designed renovation achieved energy savings of 20 per cent, with 27.5 per cent of the consumed energy supplied by the PV system. This will ensure a reduction of the specific energy of the building to only 30 kWh/m², with 42.4 per cent savings on the net-energy demand.

The designed renovation proves that it is possible to achieve nearly zero energy goals with cost-effective solutions, presenting the lighting renovation and the solar PV generation system a payback of 2.3 and 6.9 years, respectively.

This study innovated by defining ambitious goals to achieve nearly zero energy levels and presenting a design based on a comprehensive lighting retrofit and PV generation, whereas other studies are mostly based on envelope refurbishment and behaviour changes.

An indoor office space should not only provide adequate illuminance on horizontal planes but also cater to the physiological and psychological requirements of the occupants. This paper aims to describe a lighting simulation-based work conducted in Kolkata, India which modeled an indoor office to investigate the effects of variation in room surface reflectance combinations on user perception, mean room surface exitance (MRSE), average horizontal illuminance and overall uniformity of horizontal illuminance.

A fluorescent illumination system–based office space was modeled and retrofitted with tubular LED lamps in DIALux. Simulations were conducted for 16 different room surface reflectance combinations and a five-point Likert scale-type survey questionnaire was formulated to conduct a survey with 32 test subjects to assess the subjective preferability of each resultant light scene.

Simulation results demonstrate that the relationship between average horizontal illuminance and MRSE as well as between average horizontal illuminance and overall uniformity of horizontal illuminance, was statistically significant (p < 0.001). In the conducted survey, the resultant light scene arising out of the reflectance combination of wall:ceiling:floor = 60%:90%:20% was the most well-received one with 187 convinced agreements (“agree” and “strongly agree” responses).

This work found strong linear correlation between average horizontal illuminance and MRSE and between average horizontal illuminance and overall uniformity. A five-point Likert scale-type survey questionnaire with seven questions was formulated and validated with 32 test subjects (Cronbach’s alpha > 0.9295), which showed that the wall:ceiling:floor reflectance combination of 60%:90%:20% was the most favored choice.

Properly planned road illumination systems are collectively a public wealth and the commissioning of such systems may require extensive planning, simulation and testing. The purpose of this simulative work is to offer a simple approach to facilitate luminance-based road lighting calculations that can be easier to comprehend and apply to practical designing problems when compared to complex multi-objective algorithms and other convoluted simulative techniques.

Road illumination systems were photometrically simulated with a created model in a validated software platform for specified system design configurations involving high-pressure sodium (HPS) and light-emitting diode (LED) luminaires. Multiple regression analyses were conducted with the simulatively obtained data set to propound a linear model of estimating average luminance, overall uniformity of luminance and energy efficiency of lighting installations, and the simulatively obtained data set was used to explore luminaire power–road surface average luminance characteristics for common geometric design configurations involving HPS and LED luminaires, and four categories of road surfaces.

The six linear equations of the propounded linear model were found to be well-fitted with their corresponding observation sets. Moreover, it was found that the luminaire power–road surface average luminance characteristics were well-fitted with linear trendlines and the increment in road surface average luminance level per watt increment of luminaire power was marginally higher for LEDs.

This neoteric approach of estimating road surface luminance parameters and energy efficiency of lighting installations, and the compendia of luminaire power–road surface average luminance characteristics offer new insights that can prove to be very useful for practical purposes.

Green retrofitting is acknowledged as an essential strategy toward achieving long-term sustainability in the built environment. To implement this strategy successfully, the role of facility managers cannot be ignored. The purpose of this paper is to investigate present practices that are used in managing the existing facilities, to highlight the elements that govern the process of green retrofitting, and discuss the efforts and contribution of facility managers in enhancing the environmental performance of the existing facilities stock in the United Arab Emirates (UAE).

This study suggests that an adequate level of awareness of the benefits of green retrofit amongst owners and decision-makers is mostly dependent on facilities management (FM) professionals, who must establish effective communication channel with senior management. FM professionals in the UAE are well equipped and competent in greening existing buildings and can simultaneously lead a building to the path of achieving green building certification.

To examine the role of FM in a green retrofit and its current status in the UAE built environment, a two-step qualitative method was adopted. The study started by conducting semi-structured interviews with FM professionals and then assessing the insights obtained from the interviews against an actual case study of a LEED Existing Building certified facility.

Interviews were limited to FM professionals in the private sector and the results from one case study should be considered cautiously.

This paper emphasizes the primordial role of FM professionals in promoting green retrofit in the UAE.

Despite their energy conservation potential, still existing buildings are slow in embracing building energy efficiency retrofits (BEER), mainly because of the absence of a clearly defined process to deliver the BEER projects, and the lack of proactive guidance for project teams. Further, the identification of factors that can facilitate BEER projects is also important to ensure the project success. This is particularly true in energy service company (ESCO)-led projects. Hence, this study aims at investigating the decision-making process, including the motivators for the successful execution of each stage in implementing BEER when projects are outsourced to a third party.

An in-depth case study was carried out to investigate the decision-making process and motivators in implementing BEER in a selected hotel building. Seven semi-structured interviews were conducted to collect the required data within the case.

Study disclosed the 13 key decisions made and 37 key activities performed in each stage of the project. A total of 19 motivators for the successful execution of the respective stages were also elicited. Ultimately, the research findings are mapped against the five key stages of BEER decision-making process.

The outcome of this study will provide the industry practitioners a basis for the effective adoption and implementation of BEER in existing hotel buildings when an external contractor is involved.