Building Energy Efficiency Retrofit Research Articles

Life Cycle Sustainability Assessment: An Index System for Building Energy Retrofit Projects

As a major contributor to global energy consumption and greenhouse gas emissions, the building sector is crucial in shaping energy and climate change policies. Understanding building energy consumption is essential for developing effective policies, and comprehensive datasets and analyses are increasingly important. This paper outlines a structured methodology for developing a sustainability assessment index for building energy efficiency retrofits throughout a building’s life cycle, covering the design, construction, use, and out-of-use phases. It highlights the interdependencies among these phases, with the design plan influencing energy efficiency and material selection, the construction plan ensuring these goals are met, and the plans for energy management, demolition, and resource recovery focusing on sustainable practices. The keys to energy-efficient retrofits are sustainable materials, energy-efficient equipment, and green technologies, which help reduce energy consumption, emissions, and operating costs. Oversight and regulation are necessary to maintain standards. This research combines a literature review, surveys, interviews, the Delphi method, and an analytic hierarchy process (AHP) to develop a comprehensive evaluation system, categorizing 20 factors across a building’s life cycle and assigning weights based on environmental, economic, and social dimensions. The system provides a scientific basis for assessing the sustainability of energy efficiency programs, validated through consistency testing.

The low‐carbon risk society: Dilemmas of risk–risk tradeoffs in energy innovations, transitions, and climate policy

AbstractAs countries and communities grapple with climate change, they seek to rapidly decarbonize their economies and cultures. A low‐carbon future will likely depend on more distributed solar energy, the electrification of mobility, and more efficient homes and buildings. But what emergent risks are evident within this low‐carbon society? This exploratory study first reviews the existing literature to identify 75 risk–risk tradeoffs by their category, medium of distribution, and type. It builds on these 75 examples to apply a typology of Risk Offsets, Risk Substitution, Risk Transfer, and Risk Transformation. Based on extensive document analysis, it applies that typology to three low‐carbon innovations: solar energy, battery electric vehicles, and building energy efficiency retrofits, identifying 36 distinct risk–risk tradeoffs in total. As such, the paper moves to discuss complexities and challenges in risk management. In doing so, it calls for a more refined risk assessment that better accounts for decision‐making considerations such as the magnitude or probability of risk, size of population exposed, certainty in risk estimation, severity of adverse outcome, distributional considerations, and the timing of risk impacts. It also summarizes emergent research gaps. Risk management in the context of climate action becomes a three‐dimensional chess game of weighing risk transmission, risk mediums, and risk categories.

Climate-resilient building energy efficiency retrofit: Evaluating climate change impacts on residential buildings

Buildings have the potential to mitigate climate change effects by integrating energy-efficient solutions. Building resilient design strategies based on forthcoming weather predictions offers an effective means of adaptation. The study focuses on the impact of climate change on residential buildings in Istanbul and Izmir, two Turkish cities with distinctive climate characteristics. By creating future weather scenarios and conducting dynamic simulations, buildings’ and improvement measures’ performance under RCP 4.5 and RCP 8.5 climate scenarios and short- and long-term periods are evaluated. The findings reveal varying degrees of climate change impact on the two regions, with decreased heating degree days (HDDs) and increased cooling degree days (CDDs). Notably, the RCP 8.5 scenario projects significant temperature increases, with a rise of 4.3 °C in Istanbul and 5 °C in Izmir, leading to profound consequences for buildings. The CDD can be doubled in July and reach 292 in Izmir and quadrupled, reaching 158 in Istanbul. Without retrofit, in a well-naturally ventilated building, primary heating energy consumption can be decreased by 36–41 %, while primary cooling energy consumption tripled in both cities. With the aid of improvements, a ∼ 5–6 °C decrease was observed in the highest temperature predictions in naturally ventilated spaces in summer in Istanbul, while a ∼ 4–5 °C decrease was observed in Izmir.

Communication challenges and blockchain in building energy efficiency retrofits: Croatia case

PurposeAs climate change has become a growing concern, sustainable development has become increasingly important. Emissions reduction is a key step for more efficient energy use. In the last few years, the residential building sector in Croatia has received financial support for multi-dwelling building energy efficiency retrofits (EERs). However, some of these projects encountered difficulties due to information asymmetry between the key participants. This study aims to address the problem from the perspective of the principal-agent theory, which is concerned with information asymmetry and the asymmetry's repercussions.Design/methodology/approachA social network analysis is conducted to reflect the operation and management (OM) details of Croatian multi-dwelling buildings. The key stakeholders of EER are mapped, along with the contractual and communication ties between them. Using the Gephi software, relationship data are visually represented and statistically evaluated.FindingsThe analysis indicated two different clusters or groups of stakeholders in EERs in Croatia and enabled the mapping of key relationships between stakeholders. The findings stress the importance of the key relationship between owner representatives (ORs) and property managers (PMs).Originality/valueThe contribution of this study is the development of framework for blockchain implementation in EERs, which can be adapted for use in different markets and/or projects. Blockchain is proposed for minimization of information asymmetry between different stakeholders. Blockchain enables communication and cooperation during project development and enhances trust among stakeholders.

A Rational Plan of Energy Performance Contracting in an Educational Building: A Case Study

Energy performance contracting (EPC) is the best solution for an educational building to implement energy conservation measures (ECMs) because of its high capital expenditure and operational expenditure needed for retrofit and maintenance. It is also considered a win–win mechanism for organising building energy efficiency retrofit projects. It aims to assist educational buildings in acquiring new high-efficiency equipment and maximising energy use reduction, as guaranteed by energy service company (ESCO). This study developed an EPC model using regression analysis, in which the inputs are based on the data collected during the preliminary energy audit in University A. As a result, with a quantum sharing ratio of 0.95/0.5 for ESCO/University A, the forecasted energy savings from the proposed ECMs, chiller optimisation and replacement, lighting retrofit, and energy management system are estimated to save 25.6% energy use, which reduces 5,672,057 kilowatt-hour (kWh) in electricity consumption; saves RM 2,762,291.76/year; carbon dioxide (CO2) mitigation equal to 3,771,061.22 kgCO2/year; return of investment of 4.2 years with a 5% interest rate; and building energy intensity of 93.55 kWh/m2/year. A sensitivity analysis of various quantum sharing ratios found that the saving value of ESCO is inversely proportional to that of University A as the client when the quantum sharing ratio for the former is increasing.

Financial model adaptation for building energy efficiency retrofits in Turkey

Financial model adaptation for building energy efficiency retrofits in Turkey

Positive Energy District: A Model for Historic Districts to Address Energy Poverty

The Positive Energy District (PED) concept has been pointed out as key for cities' energy system transformation toward carbon neutrality. The PED may be defined as an energy-efficient and flexible urban area with net-zero energy import and greenhouse gas emissions, aiming toward annual local surplus of renewable energy. Most of the studies and practical experiences about PEDs are based on newly built districts, where the planning and integration of innovative solutions are less complex and more cost-effective. However, to achieve Europe Union's 2050 carbon-neutral ambition, we argue that the transformation of the settled districts is essential, including historic districts, which present common challenges across European cities, such as degraded dwellings, low-income families, and gentrification processes due to massive tourism flows. This paper aims to discuss how the PED model can be an opportunity for historic districts to reduce their emissions and mitigate energy poverty. The historic district of Alfama, in the city of Lisbon (Portugal), is used as a case study to show the potential of energy renovation measures and solar PV production in households, cornerstones of a PED. The annual energy needs potential reduction due to building retrofit is 84 and 19% for space heating and cooling, respectively, while the integration of building-integrated PV technologies in rooftops and windows potentially generates up to 60 GWh/year. At the district scale, these two components of the PED concept could require an investment of 60M€ to 81M€ depending on the PV technologies in the rooftops, a sensitive aspect in historical districts. Unlike other mechanisms to tackle energy poverty, like the social tariffs, the adoption of structural measures like building energy efficiency retrofit and renewable energy integration will contribute to solve the energy poverty problem, which is significant in Alfama, in both the winter and summer. The highlighted investments require an innovative financial scheme to support not only buildings' owners but also tenants, as these are among the most vulnerable to energy poverty. However, the social benefits of that investment, on the health system, air quality, climate resilience, labor productivity, and social integration, would be invaluable.

The greater the investment, the greater the loss? – Resource traps in Building energy efficiency retrofit (BEER) market

Building Energy Efficiency Retrofitting (BEER) is an important measure to relieve energy pressure, conserve natural resources and promote urban low-carbon transformation . Governments of various countries have invested huge resources to promote the rapid development of BEER market. However, when the amount of resource input exceeds a certain threshold, the market will deviate from the desired state, falling into a resource trap and cutting consumer welfare. This is due to the fact that BEER service providers take advantage of their dominant position in the market and increase their own revenues by enhancing product heterogeneity. To make matters worse, the greater the government's effort, the earlier the resource trap appears and the more resource loss it causes. Incentives and penalties for service providers became necessary to guide the market to cross resource trap. The research in this paper is conducive to promoting the healthy development of the BEER market, conserving natural resources and promoting urban low-carbon transformation.

Developing a Calcium Silicate Prefabricated Board Ventilated Wall for Building Energy Efficiency Retrofit in Hot-Humid Areas

Ventilated wall is considered as an effective technique for building energy efficiency retrofit in hot-humid areas, and the heat exchange inside the ventilated layer blocks the heat gain into the wall. Most current researches focus on the performance assessment of the wall system but lack the optimize design of the external board. Here we demonstrated a new type of ventilated wall, using the calcium silicate material as the cladding panel for its excellent physical properties and easy installation and maintenance. In particular, the aluminum foil was attached to the interior side of the board to further lower the emissivity for achieving a better insulation effect. Based on the field experiment in summer days, the thermal performance of the new type of ventilation wall was obtained and further compared with the conventional wall. Moreover, the equivalent thermal resistance of this novel ventilated wall was also calculated. The results revealed that: the interior wall surface temperature and energy consumption of the new ventilated wall proposed was about 3-5°C and 39.2% lower than those of the conventional wall, respectively. The low emissivity significantly insulated the heat transfer inside the cavity. In parallel, the calculated equivalent thermal resistance of the ventilation wall (0.971m2⋅K/W) was also 2.07 higher than that of the conventional wall.

Unlocking green financing for building energy retrofit: A survey in the western China

Energy service companies (ESCOs) play crucial role in building energy efficiency retrofit sector. However limited access to green financing has prevented ESCOs in their expansions in China. This paper, based on a survey of 469 samples and on-site visiting to and interviewing relevant 50 actors of ESCOs, financial institutions and local housing authorities, identifies main barriers of accessing to green financing at both systemic policy level and operational meso and micro level in China, and analyzes good practices at local level that overcome the barriers. The paper concludes that, although there are barriers existing at the policy level in China, substantial attentions and priorities should be given to take actions for overcoming the barriers existed at the operational meso and micro level. The paper suggests that the good practices of capacity building for ESCOs and local financial sector, intensifying participation of intermediate organizations or facilitators and diversifying financial sources and funding mechanisms and models that emerge from the local level should be disseminated in China.

Picture fuzzy multi-criteria group decision-making method to hotel building energy efficiency retrofit project selection

Building energy consumption accounts for a considerable proportion on energy consumption. To reduce building energy consumption, building energy efficiency retrofitting (BEER) based on Energy Performance Contracting mechanism is the most feasible and cost-effective method. With the increase number of BEER projects, BEER project selection has become an essential problem for energy service companies. In this paper, a multi-criteria group decision-making (MCGDM) method is proposed to deal with BEER project selection problem. First, picture fuzzy sets are employed to describe the evaluation information under the complex and uncertain environment. Subsequently, picture fuzzy weighted average operator and Laplace distribution-picture fuzzy order weighted average operator are proposed based on convex combination to aggregate individual evaluations into the overall evaluations. Furthermore, picture fuzzy TOPSIS-based QUALIFLEX method is developed to identify the optimal ranking of alternatives. Moreover, the practicality, effectiveness and advantages of the proposed MCGDM method are illustrated using a case study of hotel BEER project selection and comparative analysis. Finally, conclusions about primary contributions, and future discussions of the proposed method are demonstrated.

Overcoming barriers for building energy efficiency retrofits: insights from hotel retrofits in Sri Lanka

PurposeDespite the pressures around the world to retrofit existing buildings to have higher energy performance, still the level of adoption and implementation of Building Energy Efficiency Retrofits (BEER) appear comparatively low. The purpose of this paper is to explore the barriers that affect the successful implementation of BEER in actual project level executions and identify strategies to overcome such barriers.Design/methodology/approachIn total, two case studies were conducted in selected hotel buildings to explore the barriers that hamper the adoption and implementation of BEER in the local context and in turn identify the strategies to overcome them. Altogether 11 semi-structured interviews were conducted with respondents involved in different phases of these BEER projects. The data were analysed using code-based content analysis.FindingsAltogether 38 barriers were identified under the three main project phases. Furthermore, the study revealed 77 strategies to overcome the identified barriers, classified as individual, organisational and national level strategies.Originality/valueThis paper has made a unique contribution to the field by identifying the barriers in each phase of BEER projects and proposing strategies to be taken at different levels to overcome them. The findings of this study will provide a basis for setting up country-wide and organisation-wide strategies for successfully improving the energy efficiency of existing hotel buildings.

Changing energy cultures? Household energy use before and after a building energy efficiency retrofit

Government- and community-initiated energy retrofits of existing residential buildings abound across Europe. This paper argues that retrofitting initiatives need to extend their current emphasis on technical-material changes to include an equally strong focus on researching and potentially changing the energy-related expectations, aspirations and actual activities of those who inhabit and use these buildings. The concept of energy cultures serves as a useful heuristic to structure the analysis of household energy demand and internal environment. Covering three key elements of energy culture – 1) material conditions that relate directly to domestic energy use, 2) householders’ attitudes, perceptions and norms concerning the use of energy and 3) observable everyday practices that use energy –, and their interactions, we examine data from 20 households in a social housing estate in Ireland collected before and after retrofitting. Overall, the results highlight the urgent need for an integrated approach to energy retrofitting that combines technology-aided changes in material conditions with a parallel re-shaping of householders’ views and practices to achieve real and lasting reductions in energy use. The latter seems particularly pressing given both the persistence of many energy-intensive domestic activities and the possible emergence of rebound effects that have the potential to cancel out at least some of the savings made through retrofitting.

Crowdsourcing Model for Energy Efficiency Retrofit and Mixed-Integer Equilibrium Analysis

Most existing models of energy efficiency retrofit are able to evaluate energy saving and retrofit cost for a certain stakeholder, but unable to guide how to allocate retrofit task and incentive among multiple stakeholders. The multistakeholder situation is firstly modeled in the proposed crowdsourcing model (CM), which contributes to quantify the utility of each competitive stakeholder with respect to participation decision. To solve the CM, a Stackelberg game approach is newly developed in this article to find rational and efficient strategies of task/incentive allocation. For the building energy efficiency retrofit, the challenge of CM is to handle mixed-integer decisions of energy service companies. We prove the existence of Stackelberg equilibrium (SE), which introduces the optimal budget, and the Nash equilibrium of task allocation. To compute the SE of CM, effective search algorithms are designed based on best response and optimization techniques. Simulation results have verified the CM and game theoretical approach. The resulted SE has provided stable and efficient strategies of incentive/task allocation.

A techno-economic-risk decision-making methodology for large-scale building energy efficiency retrofit using Monte Carlo simulation

Large-scale building energy efficiency retrofit (LSBEER) involves a large number of buildings with heterogeneous characteristics. Decision-making with regard to multiple-technology portfolios, optimal implementation strategy, and regional subsidy policy is a challenging task, made particularly difficult by the presence of various uncertainties. This paper proposes a techno-economic-risk decision making methodology (TERDMM) based on Monte Carlo (MC) simulation, as well as a novel multi-aspect assessment procedure. First, an energy-saving economic benefit cost model is suggested based on life cycle cost (LCC) analysis. Second, the concept of value-at-risk is suggested as an effective measure to control risk. Third, a financial subsidy model is proposed. The model is validated with regard to database quality, energy saving effect, and accuracy. It is found that the energy-saving rate obeys a normal distribution, similar to that found for actual retrofitted buildings. In addition, the paper discusses the influence of distribution functions, varying intervals of risk variables, and different discount rates on the results of decision-making. It is found that the TERDMM can support risk-conscious decision-making by explicitly quantifying risks. It is also found that there exists a logarithmic relationship between subsidies and energy savings. Compared with the traditional method, the TERDMM is a great improvement.

The effective outsourcing of building retrofitting: key decisions and motivators

Purpose 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. Design/methodology/approach 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. Findings 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. Originality/value 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.

Research on Large-Scale Building Energy Efficiency Retrofit Based on Energy Consumption Investigation and Energy-Saving Potential Analysis

AbstractAs building energy consumption continues to grow, large-scale building energy efficiency retrofit (LSBEER) has become a trend in China, especially in existing commercial districts (ECDs). I...

Decision-making method for building energy efficiency retrofit measures based on an improved analytic hierarchy process

A large number of building energy efficiency retrofit measures (EERMs) are currently available; however, the ultimate choice of which retrofit measures should be performed is determined by many factors. The aim of this paper is to explore an application of the analytic hierarchy process (AHP) to the selection of EERMs. However, some of the limitations in the current AHP model include a large computational comparison matrix, an incomplete evaluation system, and the difficulty of integrating multidimensional factors. This paper proposes an improved AHP method to overcome these shortcomings. The improvements to the AHP focus on the normalization of the data and the influence of subjective opinions. An evaluation system was built in combination with a life cycle cost analysis. Moreover, a judgment matrix was built from multiple experts through questionnaires and the distributions of the weight factors were calculated. Furthermore, the advantages are discussed through a case study, and the results are compared with other decision-making methods. It was found that the top ranking and less desirable EERMs showed little change when using multicriteria weighted decision-making, but some policy-oriented EERM rankings showed significant changes. The case study indicated that the presented approach significantly simplified complicated multicriteria decision-making problems.

An energy-saving retrofit baseline determination method for large-scale building based on investigation data

At present, China is implementing large-scale building energy efficiency retrofit (LSBEER) due to the constraints of total energy consumption and energy use intensity (EUI). It is vital to determine the baseline of LSBEER. There are some limitations to LSBEER in the current baseline methods, such as lack of exhaustive database, mismatching with actual retrofit potential, and inapplicability of physical simulation analysis. This article proposes a baseline determination model to diminish the uncertainty and improve applicability using the example of 100 buildings in Shanghai. The methodology comprises two indexes of EUI and energy saving rate (ESR) including four methods, based on the bilateral match of retrofit target and the practical retrofit potential combined with design standards for public building energy saving. Meanwhile, evaluation indexes are proposed, such as the energy saving potential matching degree (ESPMD) and retrofit building coverage rate (RBCR). Results show that the ESR-based method has an advantage over the other three methods, with the ESPMD and the RBCR reaching 86% and 95%, respectively.

Government championed strategies to overcome the barriers to public building energy efficiency retrofit projects

Knowledge of the barriers and coping strategies for retrofitting government buildings for energy efficiency is essential for the success of these types of complex retrofitting programs. This study utilised thematic findings from two focused groups consist of government employees from two States within Australia to create a comprehensive list of barriers to retrofitting public building stock for energy efficiency and associated strategies to address them. Thematic analysis revealed that a lack of political will, financing protocols, department/agency capability, industry capability, quality assurance and misaligned incentives, are the key barriers to public building energy efficiency retrofitting projects. To address such barriers, research revealed that a government championed top-down approach is required. A key strategy identified was enabling government departments and agencies to take on debt to fund retrofit initiatives that would derive returns, in terms of reduced energy utility costs, over the short-medium term. Other important strategies included having a mandatory energy efficiency retrofitting policy, dedicated financing mechanism, flexible procurement model, facilitation team and list of pre-qualified professionals.