Retrofit Program Research Articles

Comparative study of commercial building energy-efficiency retrofit policies in four pilot cities in China

The energy efficiency of existing commercial buildings is more challenging to regulate and improve than the energy efficiency of new constructions. In 2011 and 2012, the Chinese Government selected four cities- Shanghai, Tianjin, Shenzhen, and Chongqing- to implement pilot commercial building energy efficiency retrofit program. Based on site surveys and expert interviews in these pilot cities, this research conducted a comparative analysis on incentive policies of local city level. The analysis results show that policy designs of existing commercial buildings should be further improved. The aspects that influence the implementation effect in the future, such as subsidy level, installments, and business model promotion, should be specified in the policy clauses. Referring to the technical solution and cost-benefit in Chongqing, we found that lighting system is the most common retrofit objects while envelope system is the least common one. And the subsidy incentive is greatest for educational buildings, followed by office buildings. In the end, we further discussed the problems and obstacles in commercial building retrofit market, and provided a series of recommendations.

North Torrey Pines Bridge Seismic Retrofit: Part II, Structural Analysis and Design

The historic North Torrey Pines Road Bridge in Del Mar, California, is a 15-span precast concrete tee-girder structure built in 1933. The bridge has been classified as structurally and seismically deficient and functionally obsolete, with a sufficiency rating of 19 out of 100. Through the Caltrans Retrofit and FHWA Rehabilitation Program, the structure was to be rehabilitated or replaced for improved sufficiency and to satisfy seismic life safety. The combination of complex site geology, its deteriorated state, structural irregularities, site constraints, and the requirement to preserve its historic designation presented a challenging task. The solution was a performance-based methodology, more complex than typically applied in California, which led to a unique multifaceted retrofit and rehabilitation approach. Design and analysis included detailed inelastic static analysis, secant spectral methods, and nonlinear time-history analysis with multi-support excitation. The resulting solution included ground remediation, substructure strengthening, stiffness decoupling, a replacement superstructure, and new abutments on deep foundations.

Multi-objective Optimization for a Large Scale Retrofit Program for the Housing Stock in the North East of England

In this study, a dynamic model was developed to simulate the housing stock in the North East region of England. This model takes input from the English Housing Survey database and uses EnergyPlus as its simulation engine. A range of retrofit options was applied to the housing stock, to examine the possible CO2 reductions corresponding to different scenarios. By embedding a multi-objective optimization package into the process for making decisions on retrofit solutions, it is possible to identify the most cost-effective combinations of all measures across the housing stock. By ranking the optimal solutions from the lowest to the highest cost, the trend of the uptake of individual retrofit measures could be obtained. The findings will support the development of strategies for retrofitting the housing stock in the region. This framework can be applied to housing stocks at sub-regional or national level.

Rethinking Diffusion Theory in an Applied Context: Role of Environmental Values in Adoption of Home Energy Conservation

Diffusion theory, developed and popularized within communication research by Everett Rogers, is a venerable approach with much to recommend it as a theoretical foundation for applied communication research. In developing an applied project for a home energy conservation (energy efficiency retrofit) program in the state of Nevada, we utilized key concepts from diffusion theory but also confronted its limitations. Ultimately, in this project, the diffusion of home energy conservation to individual households depended primarily not on general adoption propensity, a personality characteristic postulated by diffusion theory, or even on financial (cost-benefit) considerations, but on an environmental orientation. This result suggests revision to the diffusion of innovations idea may be needed.

Modelling Adjusted Baseline Energy in an Office Building Using Artificial Neural Network

This paper proposes Artificial Neural Network (ANN) to determine adjusted baseline energy for quantifying energy savings from an energy efficiency program implemented in an office building. The input data to the ANN includes number of working days and cooling degree days (CDD) each month for one year period before implementation of the retrofitting program. On the other hand, output data is baseline energy use (i.e. energy use before retrofit). Since the input data to the network encompasses of 36 months set of data only, Bootstrap method is used to generate more input data without changing the input and output trend of the original data set. This is performed to increase validity of the training process. Once the optimum training parameters have been obtained, adjusted baseline energy is determined by feeding the number of working days and CDDs in the post-retrofit period (i.e. 12 months set of data) to the network. Energy savings is then calculated by comparing the adjusted baseline energy with the energy use after implementing the retrofit program. The performances of the ANN model are then compared with Multi-regression technique in term of R2, Mean Absolute Percentage Error (MAPE), Mean Square Error (MSE) and Mean Absolute Deviation (MAD). Results show that the proposed ANN model has smaller errors and R2 closer to one compare to Multi-regression technique.

Multifamily energy-efficiency retrofit programs: a Florida case study

Multifamily buildings are an important target for efficiency improvements because of their energy savings potential and housing market share. Yet few multifamily retrofit projects have been completed in hot-humid regions and even fewer studies have measured and verified savings from such projects. Addressing this gap, the purpose of our research is to assess the impacts of energy-efficiency upgrades to multifamily buildings in Orlando, FL. Specifically, we measure the first-year electricity savings from retrofits to 232 units in four apartment complexes. Annual savings per unit averaged 2094 kWh (22 %) and ranged from 1700 kWh (18 %) to 3811 kWh (29 %) across complexes. Monthly savings ranged from 48 kWh (9.4 %) in December to 340 kWh (31 %) in August. From these core findings, we estimate that tenants in treatment units saved an average of $272 on their electric bills. We also find evidence to support a strategy of targeting upgrades to improve overall savings and program cost-effectiveness. Results are being used to guide development of a utility demand-side management program for multifamily property owners. Progress in this market requires additional pilot projects, access to utility data, reliable measurement and verification of savings, and innovative financing structures.

Intent and outcomes from the Retrofit for the Future programme: key lessons

The Retrofit for the Future programme, sponsored by UK government's Technology Strategy Board (TSB) from 2009 to 2013, demonstrated innovative approaches to deep retrofitting of social housing, using a whole-house approach for achieving an 80% CO2 reduction target. The intent and outcomes of this programme (in which all authors participated) are critically examined through a cross-project meta-study of the primary data, substantiated by insights from secondary sources. Given that only three (out of 45) projects met the expected CO2 target in reality, despite generous funding and professional expertise, it suggests that decarbonizing existing housing will not be particularly easy. Important lessons are found in this initiative's formulation, target setting, monitoring and evaluation procedures, and feedback mechanisms. These lessons can inform the formulation, delivery and effectiveness of future national energy retrofit programmes. Furthermore, to support the ‘scaling up’ of effective retrofit programmes and reduce the gap between intent and outcome, it is recommended that attention be moved from what level of CO2 reductions are to be achieved to how (delivery models) these radical reductions can be achieved and by whom (supply chain). Such alternative delivery models to the ‘whole house’ approach include retrofit over time, city-scale retrofit and community-based energy retrofits.

More than money: how multiple factors influence householder participation in at-source stormwater management

Urban stormwater run-off is a threat to stream ecosystems. New approaches to stormwater management aim to protect urban streams from such impacts, by retaining, treating and using stormwater at its source. As up to ∼50% of runoff from urban surfaces comes from private property, fostering stormwater retention requires effective householder engagement. We evaluated householder participation in the Little Stringybark Creek project, a stormwater retrofit programme aimed at waterway protection, using qualitative enquiry through formal and informal interviews to identify factors that influenced participation. Participation was governed by multiple factors, with financial incentives and personal co-benefits of tanks primary motivators, while process complexity and distrust were primary barriers. Results suggest an approach combining education to encourage review of subjective norms and attitudes, with incentives to mitigate behavioural controls can transform public behaviour towards sustainable stormwater management.

Retrofitting social housing in the UK: Home energy use and performance in a pre-Community Energy Saving Programme (CESP)

Improving household energy efficiency is regarded as key to significantly curtailing domestic greenhouse gas emissions. Various policy instruments have been introduced to retrofit the existing domestic building stock in the UK; however, many fail to acknowledge the significant role that occupants’ lifestyle play in energy use. The research discusses the results of a survey questionnaire administered to the residents of one of the pilot CESP schemes in Aspley, Nottingham. Factors affecting domestic energy consumption are explored, some of which relate to the building design, while others are under the direct control of the occupants. Significant findings related to home performance, home energy use, and tenants’ lifestyle are investigated in the first phase of the research. The total number of responses to the survey represents 10% of around 900 properties eligible for the CESP scheme that have not been approached for the scheme uptake. It is evident from the survey results that the majority of the sample is aware of the basic energy-saving actions in everyday life but are not likely to take up the more difficult actions. In summary, retrofit programmes will reduce carbon emissions to some degree, whereas the bigger challenge is addressing habitual household energy consumption.

The impact of domestic energy efficiency retrofit schemes on householder attitudes and behaviours

Retrofitting existing housing stock to improve energy efficiency is often required to meet climate mitigation, public health and fuel poverty targets. Increasing uptake and effectiveness of retrofit schemes requires understanding of their impacts on householder attitudes and behaviours. This paper reports results of a survey of 500 Kirklees householders in the UK, where the Kirklees Warm Zone scheme took place. This was a local government led city scale domestic retrofit programme that installed energy efficiency measures at no charge in over 50,000 houses. The results highlight key design features of the scheme, socio-economic and attitudinal factors that affected take-up of energy efficiency measures and impacts on behaviour and energy use after adoption. The results emphasise the role that positive feedback plays in reinforcing pro-environmental attitudes and behaviours of participants and in addressing concerns of non-participants. Our findings have implications for the design and operation of future domestic energy efficiency retrofit schemes.

Unravelling the unintended consequences of home energy improvements

Purpose – This paper aims to, using a systematic mixed-methods based monitoring and evaluation approach, investigate the unintended consequences of physical and technical home improvements on energy use, indoor environmental conditions and occupant behaviour in community-led retrofits. The study is part of a UK Research Council funded research project on evaluating the impacts and effectiveness of low carbon communities on energy behaviours. Design/methodology/approach – A graduated measurement, monitoring and evaluation framework has been developed and applied to gather quantitative and qualitative data on energy use and behaviours has been developed and applied to 88 households across the UK. A mixed-methods approach is used, including occupant interviews, questionnaires, activity diaries and continuous physical monitoring of energy use, environmental conditions and low-carbon technologies. Findings – The study has uncovered a number of unintended consequences associated with home energy improvements, both beneficial and detrimental, including improved comfort levels in retrofitted dwellings and reduction in energy use but also an increased likelihood of overheating following fabric improvements, potential under-performance of low-carbon systems due to lack of understanding and inadequate installation and commissioning, along with adaptive energy behaviours leading to increased energy use and a widening gap between predicted and actual savings. Research limitations/implications – Although 63 case study households are involved, it is difficult to provide statistical analysis from the emerging findings. Practical implications – This paper demonstrates the unintended consequences of home energy improvements. It aims to bring awareness of these issues to various sectors and stakeholders involved in delivering community retrofit programmes or the National Green Deal programme. Originality/value – The paper fulfils an identified need to study the impacts of home energy improvements within existing homes through a robust, comprehensive M&E approach.

Retrofit of a soft-story woodframe building using SMA devices with full-scale hybrid test verification

Soft-story woodframe buildings are prevalent in much of California and for decades have been recognized as a disaster preparedness problem for both the owners/tenants and community as a whole. Retrofit programs for these at-risk buildings have been proposed with the first such program in a major city mandated in San Francisco in 2013. In this paper, a seismic retrofit methodology for soft-story woodframe buildings is presented. The methodology utilizes seismic response modification devices that consist of a compact steel section for energy dissipation and shape memory alloy (SMA) wire for re-centering capability, should that be needed. The device can be installed within a scissor-jack brace which is known for its compact footprint and high displacement magnification factor. These characteristics make it suitable mainly because of the need for placement in or near short wall segments characteristic of the bottom floor of soft-story woodframe buildings. The retrofit methodology using the SMA-steel device in a scissor-jack brace was developed and exemplified on a three-story soft-story woodframe building. Nonlinear time history analysis was conducted to quantify the performance of the retrofitted building for a suite of earthquakes. Experimental validation consisted of a full-scale hybrid test of the three-story building with the seismic retrofit represented numerically in the first-story serving as the numerical substructure, and the upper two stories represented physically in the laboratory. The results of the full-scale hybrid test are presented thereby validating the proposed seismic retrofit using SMA-steel devices in scissor-jack braces.

Analysis and case studies of residential heat metering and energy-efficiency retrofits in China′s northern heating region

Abstract During the past 5 years, the Chinese government has organized and implemented a large-scale energy-efficiency retrofit program for existing residential buildings in China׳s northern heating region. However, many obstacles, especially lack of successful financing arrangements, have limited the implementation of retrofits under the program. This paper analyzes the key financing challenges that have faced the program, using case studies of the different financing arrangements that have been used. Some of the key issues influencing the program׳s success to date are differing retrofit and other priorities of various stakeholders, timing and methods of payback on investments, potential investors׳ lack of access to risk analysis, uncertainty about benefit sharing, and the need for revisions in policies governing retrofits and energy contracts. We make recommendations to address these issues and improve the success of the north China energy-efficiency retrofit program.

Measuring earthquake risk concentration for hazard mitigation

One of the biggest impacts of a disaster is the effect it can have on community and regional housing and the ability of people, communities and regions to recover from the damages. Policy decisions involving investments in loss reduction measures and response and recovery are best informed by the integration of scientific and socioeconomic information. Natural scientists develop hazard scenarios for stakeholders and emergency officials to assess the impacts of a particular disaster outcome. Social scientists have found that housing losses and recovery affect individuals in lower socioeconomic status disproportionately. By combining socioeconomic status data from the US Census with an earthquake scenario for southern California, an event-driven conditional distribution of earthquake risk is used to prioritize investment decisions for earthquake hazard mitigation. Simulation of the damages in the scenario showed a statistically significant risk concentration in census tracts with large numbers of residents of lower socioeconomic status living in multi-family housing and mobile homes. An application of the approach is demonstrated in Los Angeles County as a decision criterion in a building retrofit program. The earthquake scenario was used to evaluate the economic benefits of a program for voluntary mitigation and a combined program of voluntary mitigation and regulated mitigation based on socioeconomic status (mandate requiring mitigation in census tracts meeting specific damage and income thresholds). Although the analysis is a hypothetical scenario based on a simulation of a great earthquake, the results and potential outcomes show that a regulated program with a socioeconomic decision criterion would have significant benefits to vulnerable populations.

Low-carbon retrofits in social housing: Interaction with occupant behaviour

The turnover of the UK housing stock is such that CO2 emissions reduction targets will require extensive refurbishment of existing homes. Both within the literature and in practice, there is limited understanding of the interaction between housing energy efficiency refurbishment and occupant behaviour. The authors implemented interview-based qualitative research into energy-related behaviours before and after an energy efficiency refurbishment project on social housing in the north east of England. Half of the sample also received an information intervention. Template analysis identified seven key patterns affecting energy behaviour: access to knowledge and skills; nature of technical intervention; habit; external circumstances; quality of technical intervention; convenience of technology; and thermal comfort. These findings were discussed in relation to Social Practice Theory and competence, material and image as components of practice. The research provides an insight into the interaction between occupants and retrofit technologies in the context of a social housing retrofit. It is recommended that policy makers and implementers of retrofit programmes ensure that competence, material and image considerations are integral to retrofit programmes for energy use practice to change and more optimal CO2 emissions reduction achieved.

Erratum for “Bridge Seismic Retrofit Program Planning to Maximize Postearthquake Transportation Network Capacity” by Liang Chang, Fan Peng, Yanfeng Ouyang, Amr S. Elnashai, and Billie F. Spencer Jr.

Erratum for “Bridge Seismic Retrofit Program Planning to Maximize Postearthquake Transportation Network Capacity” by Liang Chang, Fan Peng, Yanfeng Ouyang, Amr S. Elnashai, and Billie F. Spencer Jr.

Selecting Target Populations for ROPS Retrofit Programs in Pennsylvania and Vermont

Agriculture has the highest injury and fatality rates when compared with other U.S. industries, and tractor overturns remain the leading cause of agricultural fatalities. Rollover protection structures (ROPS) are the only proven devices to protect a tractor operator in the event of an overturn. These devices are 99% effective when used with a seatbelt. Nearly 49% of tractors in the U.S. are not equipped with a ROPS. Interventions such as social marketing, community awareness campaigns, and financial incentives have been directed at encouraging farmers to install ROPS on their unprotected tractors. The purpose of this study was to conduct similar comparisons of ROPS protection and readiness to retrofit in different segments of the Vermont and Pennsylvania farm communities. A telephone survey was used to collect data on ROPS prevalence, farm demographic characteristics, and farmer's stage of change relative to installing ROPS on farm tractors. Our data provide new and unique information on the prevalence of ROPS-equipped tractors relative to commodity, farm size, and a variety of other demographic variables. Extrapolating from these data, the commodities studied account for roughly 162,072 tractors across the two states. Of these, 85,927 (53%) do not have ROPS. Of these unprotected tractors, 77,203 are in Pennsylvania and 8,724 are in Vermont. Our other two research questions dealt with the farmer's stage of change and possible ways to segment this population. The stage of change portion of our work demonstrates that most Pennsylvania and Vermont farmers are not contemplating ROPS retrofitting in the near future. Since no major differences were found in the stage of change, the number of unprotected tractors was examined for each of the commodity groups. In Pennsylvania, 29% of all unprotected tractors were found on cash crop farms. This trend was even more apparent on smaller farms than large farms. This led to the selection of smaller cash crop farms as the target audience for social marketing messages. In contrast, researchers in Vermont found a bimodal distribution of unprotected tractors. Of all the commodity groups surveyed in Vermont, vegetable and cash crop farmers were least likely to have even one protected tractor to use on the farm. Probably the most encouraging finding from this study is that over 85% of Pennsylvania farms and over 87% of Vermont farms surveyed had at least one tractor available that had ROPS protection. Of those farms, 25.5% of the Pennsylvania farms and 46% of the Vermont farms have ROPS on all of their tractors. Both of these findings were greater than the findings from a 2006 survey of New York State farms, which found that 75% of surveyed New York farms have ROPS on at least one tractor and 18% have ROPS on all tractors. Even with these encouraging data, the goal of 100% of tractors with ROPS is far from being met. There are still an estimated 90,000 unprotected tractors on Pennsylvania and Vermont farms, and these farm owners are currently unmotivated to install ROPS. However as demonstrated in New York State, it may be possible to use social marketing that combines persuasive messages and cost-sharing to persuade these farmers that ROPS are indeed important and accessible.

Retrofitting existing housing: how far, how much?

The significance of retrofitting the existing housing stock is considered for the policy commitment of delivering an 80% CO 2 emission reduction by 2050. Background issues of energy, legislation, potential and actual CO 2 savings, socio-economics (payback, fuel poverty, health impacts, employment stimulus, etc.) are discussed. Different potential retrofit strategies for the housing stock are presented. Three large-scale housing retrofit programmes in Wales, UK, are analysed for energy savings (using the Energy and Environmental Prediction Model), CO 2 reduction and costs. Two ‘whole house’ retrofit projects in Wales are also assessed, one of which has been the subject of long-term monitoring. Data are compared on a range of retrofit options: different strategies (elemental, multiple and whole-house measures), costs, actual CO 2 reductions and associated benefits. The findings indicate that as the cost of measures rise in relation to the predicted savings, reasonable paybacks will be difficult to achieve, particularly for finance packages such as the ‘Green Deal’. There are funding opportunities for installing ‘shallow’ elemental measures to reduce CO 2 emissions by 10–30%. However, the large-scale financing of ‘deep’ (60–80% reductions) whole-house packages of measures is not currently available and does not pay back. L'importance de la rénovation du parc de logements existants est examinée dans la perspective d'assurer l'engagement politique d'une réduction de 80 % des émissions de CO2 d'ici 2050. Les questions contextuelles touchant à l'énergie, à la législation, aux économies de CO2 potentielles et réelles, aux aspects socioéconomiques (retour sur investissement, pauvreté énergétique, incidences sur la santé, incitation à l'emploi, etc.) sont traitées. Différentes stratégies possibles de rénovation du parc de logements sont présentées. Trois programmes de rénovation à grande échelle de logements au Pays de Galles, Royaume-Uni, sont analysés en termes d'économies d'énergie (en utilisant le Modèle de prévision énergétique et environnementale), de réduction du CO2 et de coûts. Deux projets de rénovation « complète » de logements au Pays de Galles sont également évalués, dont l'un a fait l'objet d'un suivi à long terme. Les données sont comparées en fonction d'un éventail d'options de rénovation : stratégies différentes (mesures élémentaires, multiples et concernant l'ensemble de la maison), coûts, réductions réelles de CO2 et avantages connexes. Les résultats indiquent qu'au fur et à mesure que le coût des mesures augmente par rapport aux économies prévues, il devient difficile d'obtenir des retours sur investissement d'un niveau raisonnable, s'agissant en particulier de modalités de financement telles que le « Green Deal ». Il existe des possibilités de financement pour la mise en place de mesures élémentaires « légères » visant à réduire les émissions de CO2 de 10–30 %. Cependant, le financement à grande échelle de trains de mesures « lourdes » concernant l'ensemble de la maison (réductions de 60–80 %) n'est pas actuellement disponible et ne permet pas le retour sur investissement. Mots clés: parc bâti, énergie, logement, bas carbone, politique publique, réhabilitation, rénovation

Bridge retrofit prioritisation for ageing transportation networks subject to seismic hazards

The deteriorating state of highway bridges is traditionally ignored in estimating the seismic reliability of transportation networks. In this study, the present day seismic reliability of ageing bridges in highway networks is evaluated through a time-dependent seismic fragility analysis of typical bridge classes. An efficient algorithm based on finite-state Markov Chain Monte Carlo simulations is also presented to assess the reliability of large ageing highway bridge networks without the need to simplify the network topology. The criticality of ageing bridges is then assessed through different proposed ranking strategies to arrive at an optimised seismic retrofit prioritisation. A case study on an existing bridge network with 515 bridges in the state of South Carolina, USA reveals striking differences between results of the proposed ranking strategies and those from state-of-the-practice methods. Such differences emphasise the significance of accounting for network-level importance in seismic retrofit programs of ageing transportation networks.

Dedicating new real estate transfer taxes for energy efficiency: A revenue option for scaling up Green Retrofit Programs

As the labor market in the U.S. remains weak, with high unemployment and sluggish job growth, policymakers at various levels of government are looking for new ways to support job growth and investment during an increasingly tight fiscal climate. Policies that promote the “Green Economy” in general and energy efficiency in particular remain politically popular as potential win–win solutions that will create jobs and curb greenhouse gas emissions. Yet, efforts to promote energy efficiency in the residential sector through rebates and incentives alone have yet to reach critical mass. This paper outlines a policy option for state and local governments to use real estate transfer taxes to generate stronger incentives for home buyers to undertake significant retrofit projects at the time of sale. The economic impact of the proposed energy efficiency transfer tax (EETT) is then modeled for the State of North Carolina, using standard input–output techniques. Ultimately, based on housing sales figures from 2010, a new EETT of 2.5 percent on home purchases would generate a net positive increase of approximately 3485 direct construction jobs and 5900 annually total jobs for the state.