Energy Efficiency Interventions Research Articles

Impacts of HVAC cleaning on energy consumption and supply airflow: A multi-climate evaluation

Energy-efficiency interventions are crucial for sustainable building operations to accommodate emerging indoor air quality (IAQ) criteria into their engineering life cycles. While several studies have addressed building energy consumption and IAQ considerations separately, few provide integrated analysis of these aspects in response to building hygiene practices. In response, this study evaluates the effectiveness of routine heating, ventilation, and air conditioning (HVAC) cleaning on energy consumption and supply airflow patterns in non-residential public buildings. This study juxtaposes HVAC energy consumption and ventilation performance before, during and after routine HVAC cleaning, across buildings situated in four different climate zones, while operating in cooling mode. Each site had nearly identical HVAC systems serving similar architectural features and occupational loads; these were segregated into an intervention (cleaned HVAC system) that could be compared to an otherwise identically operating HVAC (control system), which was not cleaned. Following prescriptive cleaning, HVAC systems exhibited significant energy consumption reductions and delivered higher airflows compared to their uncleaned counterparts. On average, intervention systems saved between 41 % and 60 % on conveyance (fan/blower) energy, with one exception, and supplied 10 % and 46 % more airflow compared to their uncleaned counterparts. This research demonstrates how a new generation of low-cost HVAC system monitors can compile Internet of Things (IoT) archives to show immediate energy consumption benefits associated with cleaning HVAC components and their associated ductwork serving relatively high occupancy commercial and educational spaces.

Navigating the Challenges of Sustainability in the Food Processing Chain: Insights into Energy Interventions to Reduce Footprint

This review paper examines the critical intersection of energy consumption and environmental impacts within the global food system, emphasizing the substantial footprint (including land usage, costs, food loss and waste, and carbon and water footprints) associated with current practices. The study delineates the high energy demands and ecological burdens of food production, trade, and consumption through a comprehensive bibliographic analysis of high-impact research papers, authoritative reports, and databases. The paper systematically analyzes and synthesizes data to characterize the food industry’s current energy use patterns and environmental impacts. The results underscore a pressing need for strategic interventions to enhance food system efficiency and reduce the footprint. In light of the projected population growth and increasing food demand, the study advocates for a paradigm shift towards more sustainable and resilient food production practices, adopting energy-efficient technologies, promoting sustainable dietary habits, and strengthening global cooperation among stakeholders to achieve the Sustainable Development Goals. Investigations have revealed that the food system is highly energy-intensive, accounting for approximately 30% of total energy consumption (200 EJ per year). The sector remains heavily reliant on fossil fuels. Associated greenhouse gas (GHG) emissions, which constitute 26% of all anthropogenic emissions, have shown a linear growth trend, reaching 16.6 GtCO2eq in 2015 and projected to approach 18.6 GtCO2eq in the coming years. Notably, 6% of these emissions result from food never consumed. While the water footprint has slightly decreased recently, its demand is expected to increase by 20% to 30%, potentially reaching between 5500 and 6000 km3 annually by 2050. Energy efficiency interventions are estimated to save up to 20%, with a favorable payback period, as evidenced by several practical implementations.

A Workflow for a Building Information Modeling-Based Thermo-Hygrometric Digital Twin: An Experimentation in an Existing Building

Building Information Modeling (BIM)-based digital twin (DT) could play a fundamental role in overcoming the limitations of traditional monitoring methods by driving the digitalization of the construction sector. While existing studies on the topic have provided valuable insights, significant knowledge gaps remain, which continue to hinder the large-scale adoption of this approach. Moreover, to date, there is no standardized procedure available, able to guide the step-by-step creation of a DT. Another significant challenge concerns the choice of technologies able to integrate perfectly with each other throughout the process. This paper outlines a comprehensive workflow for creating a digital twin (DT) of an existing building and proposes various solutions to improve the integration of different technologies involved. These enhancements aim to address the limitations of current monitoring methods and leverage the advantages of BIM and DT for accessing and managing monitoring data, ultimately facilitating the implementation of energy-efficient interventions. This work examines the concept of “Living Lab” in an office building also used as an academic laboratory. The created DT allowed for real-time remote monitoring of four rooms, each with a different functional and occupational characteristic, useful also for future predictive analyses.

Towards a Relational Sociology of Retrofit

Decarbonisation of residential buildings (‘retrofit’) is vital if nations are to meet declared net zero targets. This challenge is especially acute in the UK, which has some of the least energy efficient homes in Europe. Yet, to date, sociology has paid relatively little attention either to the urgency of this challenge or to its potential solutions. This article uses concepts from relational sociology to propose a complete reframing of the retrofit challenge and concludes by offering suggestions to improve energy policy design and incentives. It opens new avenues for sociologically driven research into how and why people ‘retrofit’ their homes, highlighting dynamics of trust, power and emotion as meaningful barriers to retrofit at scale. We conclude that the multiple stakeholders seeking to boost energy efficiency interventions in homes should focus less upon economic incentives for ‘rational actors’ and more upon reducing, facilitating and smoothing the ‘relational work’ needed to deliver retrofit.

Comparative Study of Energy Consumption Intensity: A Case Study of the Faculty of Electrical Engineering and Informatics (FEI) Versus the Faculty of Chemical Technology (FChT) in the City of Pardubice

Abstract The study’s comparative aspect between the Faculty of Electrical Engineering and Informatics (FEI) and the Faculty of Chemical Technology (FChT) buildings is pivotal for elucidating nuanced differences in energy consumption practices within academic institutions, facilitating targeted energy efficiency measures. The research methodology adopts a comparative case study approach to examine two focal research buildings. Analysis entails computing energy consumption intensity per unit area for both buildings and comparing energy consumption data to identify disparities. The need for understanding energy consumption patterns and improving energy efficiency in academic infrastructure is directly addressed through variables studied in the comparative analysis, including energy consumption comparison, annual and monthly variations, ratio, and intensity. The data indicates that the average heating intensity in the FChT building surpasses that of the FEI building by a factor of 2.3, signifying significant disparities in heating energy consumption trends between the two structures and suggesting potential areas for targeted energy efficiency interventions. Moreover, the average electrical intensity in the FChT building is over 1.7 times higher than in the FEI building. Interestingly, despite the FChT building being 2.6 times larger than the FEI, its intensity does not always correspond with the increase in building area, indicating additional factors influencing energy consumption.

Harnessing machine learning algorithms to unveil energy efficiency investment archetypes

Increasing transparency about the performance of different projects is crucial to reducing the heterogeneity in the energy efficiency services market, thereby upscaling investments. In this context, machine learning algorithms could assist in identifying and analyzing energy efficiency project archetypes, although this field has so far been explored with a limited view in the literature. This paper aims to address this gap by identifying energy efficiency investment families and the determinant factors of the classification scheme, using machine learning. In this effort, it hinges on a wide range of indicators from implemented projects around Europe and the USA, including investment profitability, initial investment, risk of failure, intervention type, life measure, region of implementation and building type. The analysis employs two clustering approaches, namely Partitioning Around Medoids (PAM) and K-means, determining the number of clusters based on the Silhouette index and total within–cluster sum of squares. The results indicate that energy efficiency investments can be classified into three categories: (i) “junk investments”, characterized by low–profitability (IRR∼10%), moderate risk, and extended horizons; (ii) “safe profitability”, distinguished by high profitability (IRR∼30%) and minimal risk; and (iii) “high stakes”, described by exceptionally high profitability (IRR∼40%), coupled with a substantial risk. Next to profitability and risk of failure, also energy efficiency intervention and building type (sector) emerge among the most influential factors in the classification scheme. Feature importance shows a significant sensitivity to the chosen classification model.

Building blocks of change: The energy, health, and climate co-benefits of more efficient brickmaking in Bangladesh

The brick manufacturing industry in Bangladesh is characterized by informal inefficient coal-burning kilns that emit substantial greenhouse gases and air pollution. Despite decades of regulatory measures and the promotion of advanced kiln technologies, informal kilns persist. We employed a multiphase, interdisciplinary, mixed-methods approach to identify solutions. In this paper, we first summarize past approaches and discuss the key barriers we identified to improving the industry, then we present the design, and results of a randomized pilot energy efficiency intervention designed to overcome barriers to improved kiln operation. Our approach emphasized collaborating with informal zigzag kiln owners, who constitute the majority of brick producers, and carefully considering their incentives for changing a profitable business model. The intervention achieved high (60 %), including from non-study kilns, highlighting its appeal. Our findings provide insights into key elements for a successful intervention strategy that can be applied in larger-scale studies, not only for brick manufacturing but also for addressing broader environmental and health challenges.

Does carbon pricing policy improve energy efficiency? New evidence from Canadian provinces

ABSTRACT Given the increasing damage effect of climate change, the Canadian government has taken a further step to ensure that carbon pricing is implemented in all provinces to reduce its GHGs emissions as a means of addressing climate change. Thus, this paper examines the effect of carbon pricing on energy consumption which is the main source of CO2 emission to enhance our understanding beyond carbon-pricing effects on households and revenue recycling in the prior research. Our study analyzes the energy efficiency of Canada using the province-level data between 2000 and 2021, by developing an SFA production model to understand the drivers of energy consumption and then compute the total factor energy efficiency index while controlling for the role of carbon pricing. Our empirical results reveal that increased labor input, as well as output, mitigate the rising capital-induced energy consumption, while carbon pricing policy plays no significant role in influencing energy consumption. However, the effectiveness of carbon pricing is found in reducing province-level energy efficiency. This striking evidence suggests that policymakers should consider a labor-oriented energy saving scheme and conduct a comprehensive review of the current carbon pricing policy in order to align with energy efficiency interventions toward the achievement of Canada’s Paris Agreement targets.

Clean energy for a sustainable future: Analysis of a PV system and LED bulbs in a hotel

Scholars are increasingly prioritising sustainability as the driving force behind their research efforts, and many businesses are placing the customer at the centre of their agendas. Hospitality facilities, such as hotels, are also making concerted efforts to mitigate climate change. The present study proposed a sustainability analysis of the installation of a photovoltaic (PV) system and the replacement of conventional lighting with light emitting diode (LED) bulbs in a hotel, considering economic, environmental and social sustainability dimensions.The results showed that NPV varied between 967 and 3624 €/kW for the PV system, with a 100 % probability of achieving a positive NPV in a high market scenario and a 79–84 % probability of the same in a low market scenario. Concerning energy efficiency, the adoption of LED bulbs determined a NPV in the range of 105–216 €/bulb. These figures were highly dependent on the percentage of self-consumed energy and the purchase price of electricity. Environmental analyses indicated that the installation of a PV system could lead to an emissions reduction of 422 gCO2eq/kWh, translating to 61 tCO2eq/year. In addition, social analyses underscored the significance of renewable installations and energy-efficiency interventions to support the ecological transition. However, consumer choices within hotels did not consistently align with sustainable models. Notably, a green premium of 13.2 €/day was recognised for hotels using renewable systems, and 8.3 €/day for those using smart lighting. The results advocate for a pragmatic sustainability model that sees green investments enhancing a hotel's sustainability. However, a shift in consumer attitudes is necessary to fully realise this potential.

Evaluation of Energy Performance Indicators and Energy Saving Opportunities for the Italian Rubber Manufacturing Industry

The objective of this work is the energy characterisation and evaluation of the energy efficiency potential of the rubber manufacturing industry in Italy, exploiting the detailed data included in energy audits by large and energy-intensive companies. This sector is divided into two sub-activities: the manufacture of rubber products and the production of tyres. Existing studies are focused mainly on tyre production, and there is a lack of quantitative evaluation of energy indicators that can provide guidance for improving process efficiency. In this work, updated global and specific energy performance indicators (EnPIs) related to the production process and to the auxiliary and general services are defined and evaluated. At the same time, targeted actions and interventions to improve the energy efficiency of the sector are analysed, showing the role of different intervention areas and their cost-effectiveness. The analysis is based on 100 Italian mandatory energy audits of the sector collected according to Art.8 EU Directive 27/2012. The applied methodology made it possible to calculate specific energy performance indicators by considering the overall and sub-process energy consumption of different production sites. Based on a detailed database containing real data from recent energy audits, this study provides an up-to-date and reliable benchmark for the rubber industry sector. In addition, the analysis of energy audits allows the identification of the most effective energy efficiency interventions for the rubber industry in terms of cost-effectiveness and payback time.

Analysis of business models for delivering energy efficiency through smart energy services to the European commercial rented sector.

In this paper, we perform a comparative analysis of business models used by Energy Service Companies (ESCOs), suitable for the deployment of energy efficiency measures in the commercial rented sector across Europe. These models can effectively contribute to solving the split-incentive issue that arises in the rented building scenario. Some of them are obtained from their "traditional" counterparts, which do not consider the rented scenario, but just a bipartite agreement between an Energy Service Company and its client. The EU Horizon 2020 project SmartSPIN (Smart energy services to solve the SPlit INcentive problem in the commercial rented sector) targets delivery of enhanced energy services for commercial rented sector. These enhanced energy services (a) combine demand management services and energy efficiency interventions, (b) facilitate the adoption of renewables, (c) optimize the balance between demand and supply, (d) alleviate the split incentive issue. The pilot implementation of SmartSPIN is in progress in a business park in Greece, in an office building in Ireland and in two shopping centers in Spain. Key recommendations toward the implementation of such a smart energy service are provided in this paper. They have been obtained from a detailed analysis of ten interviews of key stakeholders of the energy efficiency sector and of the commercial rented sector, along with an analysis of a selection of the most relevant technical literature. This paper argues that the classical shared savings and guaranteed savings ESCOs models may be adapted to the commercial rented sector and used at SmartSPIN's demonstration sites in Spain, Greece and Ireland. The guaranteed savings model appears to be the most appropriate one to use when the building owner is funding the energy efficiency project using own funds or liaising directly with a bank or other finance provider. The validation method for the comparative analysis of business models and selection of the most appropriate one is based on both literature review and consultation of selected stakeholders' (stakeholder value creation framework).

Financial Barriers in Energy Efficiency Adoption among Low-Income Households: A Bibliometric Analysis

This study conducts a comprehensive bibliometric analysis of the Scopus database spanning from 2019 to 2024, examining the complex issue of financial barriers impeding the adoption of energy efficiency interventions in economically constrained households. It sifts through the layers of academic research to distill prevalent themes, identify emerging research trends, and pinpoint voids within the scholarly dialogue. The analyses reveal a salient narrative, financial barriers pose a formidable barrier to adopting energy-saving technologies in low-income sectors. These findings underscore the vital intersection of economic capacity and environmental sustainability and illuminate the areas where future research and policy initiatives can intersect to drive meaningful progress.

Review of Industrial Heating and Potential Low-carbon Fuels in the Context of Nepal.

Process heating is an important step in manufacturing industries such as metal, cement, brick, food, etc., and accounts for a large share of the total energy consumption of those industries. In Nepal, process heating alone accounts for around 64% of the process energy of the manufacturing sector. Around 64% of Nepalese industries’ energy demand for process heating is supplied by high-carbon emitting fossil fuels such as coal, diesel, etc. The industrial sector is responsible for significant global greenhouse gas emissions. Nepalese manufacturing Industries emit around 0.002248 GT of CO2 annually. The movement toward carbon neutrality has prompted many countries around the world to look for clean and sustainable fuel to meet their decarbonization goal. This study overviews Nepalese industries’ different industrial heating processes in terms of energy consumption, emissions, energy efficiency measures and interventions, and renewable options from a literature review and using data from secondary sources. Based on the data collected and the literature review of the industries, the potential low-carbon fuels which can be compatible with heating applications in Nepalese industries are reviewed. This paper concludes with recommendations for the future decarbonization of process heating in Nepalese industries.

A Review of Energy Efficiency Interventions in Public Buildings

This research provides a comprehensive exploration of energy efficiency dynamics in non-residential public buildings such as schools, swimming pools, hospitals, and museums. Recognizing the distinct energy consumption patterns of each building type, the study accentuates the unique challenges they present, with a particular focus on the continuous and intensive energy demands of hospitals and the unparalleled energy needs of swimming pools. Through an extensive review of various case studies, the research unveils prevailing energy consumption trends, highlighting the role of metrics in assessing energy efficiency and the inherent challenges these metrics face in ensuring uniformity and direct comparability. A core element of this analysis emphasizes the dual nature of technical retrofitting, categorizing interventions into passive and active measures. The research delves into the sustainability imperatives of energy interventions, exploring the economic motivations underpinning retrofit decisions, and the intricate relationship between advanced technological solutions and the behavioral tendencies of building operators and users. Additionally, the study uncovers the influence of external determinants such as climatic factors and government policies in shaping energy consumption in public buildings. In synthesizing these findings, the paper offers insightful recommendations, emphasizing the need for an integrated approach that harmonizes technological innovations with informed operational habits, aiming to optimize energy efficiency in public non-residential buildings.

Energy-Efficient Solutions: A Multi-Criteria Decision Aid Tool to Achieve the Targets of the European EPDB Directive

The building and construction sector has a significant impact on the CO2 emissions and pollutants released into the atmosphere, which contribute to climate change. The EPDB Directive mandates the achievement of minimum energy class E for all residential buildings by 2030 and energy class D by 2033. Particularly, in Italy, about 86% of the existing building stock predates the enactment of any energy laws or regulations, making it imperative to apply the energy efficiency interventions. This paper provides a support decision tool for the identification of the standardized interventions in the building envelope, the air conditioning system, and domestic hot water production. This study is focused on a specific construction period class (1976–1990) in six different climatic zones. The methodological approach is based on a cataloguing phase and the definition of ante operam energy classes as well as on case study identification, energy requalification intervention identification, solution simulations, and cost estimation. By simulating the standardized interventions for each climatic zone, a range of possible combinations is identified. The most advantageous ones are determined based on a cost–benefit analysis considering the potential class jump achieved. The research result is a matrix of energy efficiency interventions that is applicable to each climatic zone and can be extended to the existing housing stock.

School building energy efficiency and NO2 related risk of childhood asthma in England and Wales: Modelling study

BackgroundClimate change legislation will require dramatic increases in the energy efficiency of school buildings across the UK by 2050, which has the potential to affect air quality in schools. We assessed how different strategies for improving the energy efficiency of school buildings in England and Wales may affect asthma incidence and associated healthcare utilization costs in the future. MethodsIndoor concentrations of traffic-related NO2 were modelled inside school buildings representing 13 climate regions in England and Wales using a building physics school stock model. We used a health impact assessment model to quantify the resulting burden of childhood asthma incidence by combining regional health and population data with exposure-response functions from a recent high-quality systematic review/meta-analysis. We compared the effects of four energy efficiency interventions consisting of combinations of retrofit and operational strategies aiming to improve indoor air quality and thermal comfort on asthma incidence and associated hospitalization costs. ResultsThe highest childhood asthma incidence was found in the Thames Valley region (including London), in particular in older school buildings, while the lowest concentrations and health burdens were in the newest schools in Wales. Interventions consisting of only operational improvements or combinations of retrofit and operational strategies resulted in reductions in childhood asthma incidence (547 and 676 per annum regional average, respectively) and hospital utilization costs (£52,050 and £64,310 per annum regional average, respectively. Interventions that improved energy efficiency without operational measures resulted in higher childhood asthma incidence and hospital costs. ConclusionThe effect of school energy efficiency retrofit on NO2 exposure and asthma incidence in schoolchildren depends critically on the use of appropriate building operation strategies. The findings from this study make several contributions to fill the knowledge gap about the impact of retrofitting schools on exposure to air pollutants and their effects on children's health.

Assessing housing exposures and interventions that impact healthy cities: a systematic overview of reviews.

There are direct links between housing and health. However, there is a lack of systematic reviews that bring together the evidence to outline the health impacts of exposures in housing and housing interventions. This article aims to address this gap by synthesising systematic reviews on the themes of housing exposures and interventions. We searched four databases: Scopus (Elsevier), PsycINFO (OvidSP), Science Citation Index and Social Science Citation Index (Web of Science Core Collection), and the Sociology Collection (Proquest). We used keywords related to 'health' and 'city*' and included all types of reviews. We extracted data into a predesigned extraction form and synthesised information narratively. 745 articles were identified and screened, of which 256 reviews were included and 16 (6%) related to housing. All reviews related to housing exposures found that poor housing, including crowding, coldness, dampness, mould, and indoor air pollution had a negative impact on health. Most reviews found that housing interventions such as housing refurbishment, heating, and energy efficiency interventions positively impacted health outcomes. An online toolkit was developed to disseminate and communicate this research: https://www.healthycitiescommission.org/toolkit/. Governments have a pivotal role in addressing health issues related to housing interventions and exposures in housing. This includes interventions through building regulations following international guidance and financial assistance to encourage housing modifications that will improve health.

Research trends in phase change materials (PCM) for high-performance sustainable construction

In the face of escalating environmental perils driven by climate change and global warming, there is an urgent call for innovative and sustainable energy solutions, especially within the construction sector, which is a major consumer of energy and emitter of greenhouse gases. Among various energy-efficient interventions, Phase Change Materials (PCMs) have emerged as a promising technology for passive thermal regulation in buildings. This review paper delves into recent advancements in integrating PCMs within building envelopes, which serve to store thermal energy, thus reducing temperature fluctuations and enhancing indoor comfort levels. The study also underscores the increasing global demand for energy storage systems in pursuit of a low-carbon economy and how PCMs can address this imperative. A special focus is given to applications of PCMs in diverse climatic zones, and the paper offers insights into the thermo-physical properties that make them amenable for building integration. Furthermore, the paper reveals that paraffin wax is the most extensively used PCM and discusses the relevance of selecting PCMs based on their melting points, which is pivotal for optimizing heat transfer efficiency. This study also highlights the need for extensive real-world, full-scale evaluations of PCMs, and the importance of scrutinizing their impact on the mechanical properties of building materials. The lifecycle and cost analyses of PCM integration, which are often overlooked, are identified as crucial areas for further research. Through a comprehensive review of global applications and experimental findings, this paper accentuates the potential of PCMs in revolutionizing building energy efficiency, cooling-heating systems, and integration in concrete, mortar, walls, and solar energy applications while also calling for continued research into performance enhancement and understanding potential drawbacks. This underscores the pivotal role of PCMs in steering the construction industry towards sustainability and energy conservation.

Lessons Learnt and Policy Implications from Implementing the POWERPOOR Approach to Alleviate Energy Poverty

Energy poverty is a multifaceted phenomenon that affects many Europeans. Alleviating energy poverty is high in the EU, national, and local policy agendas. Despite the attention the phenomenon has been gaining from a policy perspective, especially after the current energy crisis, there are still some gaps due to the complexity of the issue and its vastly different manifestations across Europe. This manuscript presents the policy implications stemming from the implementation of the POWEPROOR approach in alleviating energy poverty in eight European countries, as co-created with relevant stakeholders in each country. The knowledge gained from empowering energy-poor citizens by promoting behavioural changes and small-scale energy efficiency interventions, as well as by encouraging the uptake of renewable energy sources in the form of collective energy initiatives while leveraging innovative financing schemes, resulted in policy recommendations for national and sub-national governments and lessons for civil society and the private sector.

Analysis on the energy efficiency, thermal performance and infection intervention characteristics of interactive cascade ventilation (ICV)

Floor radiation (FR) is one of the widely used heating modes in winter. However, the widespread and high outbreak of Corona Virus Disease 2019 (COVID-19) has made the disadvantage of floor radiation that lacks fresh air and air movement exposed as a deficiency. To seek a heating mode that can realize a comfortable and healthy indoor environment with low cost, the interactive cascade ventilation (ICV) coupling with multiple low-grade sources was proposed in this study. Energy efficiency, thermal comfort and air quality were investigated by comparing with FR and floor radiation with mixing ventilation (FRMV). The results showed that by elevating the same indoor temperature, ICV can reduce indoor heat transfer by 28.41% and 30.94% than FR and FRMV, respectively. And ICV also presented the highest system COP by introducing multiple low-grade sources. In terms of thermal comfort, the indoor environment served by ICV was closer to thermal neutrality, and the subjective thermal comfort can also be enhanced by 10% and 8% relative to FR and FRMV. The CO2 test results indicated that by introducing the ICV, indoor air quality can be improved by 36.68% and 61.45% over FR and FRMV with the contaminant removal rate significantly accelerated. During the pandemic, ICV can reduce the COVID-19 infection rate by 9.6% and 55.5% within 8 h and 30 min compared with FRMV. The conclusions obtained in this paper can provide new ideas for designing air conditioning systems in the epidemic and the context of carbon reduction.