58 research outputs found

    Scalable dynamic simulation-based methodology for the energy retrofit of existing buildings

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    It is widely recognized that the building sector largely contributes to the total European energy consumption with a 40% influence on the total assessed energy uses. To this regard the EPBD recast Directive promotes nearly zero energy buildings (nZEB) for the public and the private sector as a mandatory requirement by 2020. Given the low energy efficiency of old buildings, concerns about the state of the existing building stock should be seriously considered as most of the energy consumption is attributable to the existing buildings. Additionally, residential buildings are often seen as long-term assets, setting thus a low replacement rate, approximately 1% per year in Europe, of old buildings by new ones. To this regard, larger energy savings can be achieved with the energy retrofitting of the existing building stock, rather than with the construction of relatively small proportion of new high performing buildings. Therefore, the refurbishment of the existing building stock has to be primarily planned and accomplished in order to achieve a timely reduction on the buildings energy consumption. Concerning this, the EPBD recast, as policy driver for reducing European energy use in buildings, has been representing the first and main legislative reference. According to it Member States must ensure that minimum energy performance requirements are set with a view of achieving at least cost-optimal levels for buildings, building units and building elements” by means of a comparative methodology framework applied to new constructions and existing buildings undergoing major renovations. The methodology specifies how to compare energy efficiency measures in relation to their energy performance and to the cost attributed to their implementation, and how to apply these to selected reference buildings with the aim of identifying cost-optimal levels of minimum energy performance requirements. A cost optimal level is defined as the energy performance level, which leads to the lowest cost during the estimated economic lifecycle of the building. A measure is considered cost-effective when the cost of implementation is lower than the achievable benefits, during the expected life of the measure. This type of analysis allows defining energy renovation scenario based on their energy and economic optimum. Within the complex scenario described above, this Ph.D. thesis aims to provide a scalable methodology for the definition of energy retrofit scenarios to be applied to existing buildings, based on the use of dynamic building simulation models. The methodology targets the existing building stock given the large energy savings that can be achieved from existing buildings. It builds on an energy and economic assessment of energy efficiency measures applied to different building typologies. The energy and economic assessment are respectively carried out by means of dynamic building simulation and a cost-optimality approach. The cost optimal analysis was chosen for the aim of this study for its systematic approach in defining energy retrofit interventions based on their energy and economic optimum. The term “scalable” is used for defining the methodology as the studied energy retrofit scenarios can vary depending on the “scale” of the study. Two main scales of buildings can be distinguished: building stock or single buildings. When retrofit interventions are studied to be applied to wide portion of the building stock, as for example at national level, representative building models are used. They correspond to reference buildings representative of a certain building typology, construction age and geographic location. Within this thesis, a methodology for their definition was defined and various reference buildings for the Italian context were created. On the contrary, when it is necessary to study specific and customized retrofit measures, a single existing building is modelled. In this case, compared to the case of the reference buildings, larger quantity of data and a higher degree of detail are necessary. These building models are customized based on the existing buildings characterization (e.g. building envelope, system, etc) and when applicable, based also on data from monitoring. To this regards, when detailed information about the building real operation from monitoring is available, the building model need to be calibrated based on measured data. For a model to be calibrated, the building energy consumption predicted by the simulation program, has to match the consumption measured from monitoring. Calibrated models can be used for comparing the baseline situation of the building (calibrated and not retrofitted) with other simulation results relative to the application of building renovation interventions. To this regard, within this Ph.D. thesis, a literature review on the most common calibration techniques currently in use for the calibration of building models was conducted. Additionally two case studies were calibrated by means of two different approaches: a trial and error approach and an optimization-based calibration. For both scale of buildings (building stock and single buildings), dynamic building simulation was employed for the energy assessment. Building simulation application has expanded since mid-‘70s building simulation as an attempt to emulate reality. To date, it is much more common to employ building simulation in post construction or advanced building design phases rather than in early phases. In particular building simulation is frequently used for the prediction of energy savings by assessing energy retrofit interventions on existing buildings. To this regard, given its wide application and the high level of detail of the analysis performed (dynamic analysis), building simulation was chosen within this thesis, as a tool for the energy assessment of buildings and of the relative energy renovation interventions. Finally, the economic assessment of the energy retrofit measures was carried out by means of the cost optimal methodology, as defined by the EPBD recast. The methodology allowed defining energy renovation interventions based on their economical and energy optimum. The Directive requires to define different packages of energy efficiency measures, which can be applied to reference representative buildings but also to single and existing building for energy and economical assessments. The energy assessment of a building can be carried out with analytical or simplified methods, but dynamic building simulation is strongly suggested, as performed within this thesis. For the economic assessment, the global cost method was employed based on the calculation method of the Standard EN 15459 as advised by the EBPD. The global cost method considers, for each energy efficiency measure, the initial investment, the sum of the annual costs for every year (including energy costs) and the final value, all with reference to the starting year of the calculation period. In order to define different energy retrofit solution and set the minimum energy performance requirements, within the Ph.D. thesis, the cost optimal approach was applied to both the considered scale of buildings: to the building stock scale with three reference buildings, and to the single buildings scale with two calibrated buildings. A set of energy efficiency measures was defined and applied to the case studies for evaluating the financial and energy performance gap between the cost-optimal solutions and nZEB levels, respectively. For the building stock, different energy retrofit solutions are defined as final outcomes. Given the use of representative models (reference buildings), the retrofit solutions can be replicated to several buildings, among the same building typology. In this sense, different energy retrofit solutions can be established. On the other hand, for single buildings, the energy retrofit solution studied is specific and customized barely to the analyzed case study

    Methodologies and advancements in the calibration of building energy models

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    Buildings do not usually perform during operation as well as predicted during the design stage. Disagreement between simulated and metered energy consumption represents a common issue in building simulation. For this reason, the calibration of building simulation models is of growing interest. Sensitivity and uncertainty analyses play an important role in building model accuracy. They can be used to identify the building model parameters most influent on the energy consumption. Given this, these analyses should be integrated within calibration methodologies and applications for tuning the parameters. This paper aims at providing a picture of the state of the art of calibration methodologies in the domain of building energy performance assessment. First, the most common methodologies for calibration are presented, emphasizing criticalities and gaps that can be faced. In particular the main issues to be addressed, when carrying out calibrated simulation, are discussed. The standard statistical criteria for considering the building models calibrated and for evaluating their goodness-of-fit are also presented. Second, the commonly used techniques for investigating uncertainties in building models are reviewed. Third, a review of the latest main studies in the calibrated simulation domain is presented. Criticalities and recommendations for new studies are finally provided

    Cost-Optimal Analysis for nearly Zero Energy Buildings design and optimization: A critical review

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    Since the introduction of the recast of the EPBD European Directive 2010/31/EU, many studies on the cost-effective feasibility of nearly zero-energy buildings (NZEBs) were carried out either by academic research bodies and by national bodies. In particular, the introduction of the cost-optimal methodology has given a strong impulse to research in this field. This paper presents a comprehensive and significant review on scientific works based on the application of cost-optimal analysis applications in Europe since the EPBD recast entered into force, pointing out the differences in the analyzed studies and comparing their outcomes before the new recast of EPBD enters into force in 2018. The analysis is conducted with special regard to the methods used for the energy performance assessment, the global cost calculation, and for the selection of the energy efficiency measures leading to design optimization. A critical discussion about the assumptions on which the studies are based and the resulting gaps between the resulting cost-optimal performance and the zero energy target is provided together with a summary of the resulting cost-optimal set of technologies to be used for cost-optimal NZEB design in different contexts. It is shown that the cost-optimal approach results as an effective method for delineating the future of NZEB design throughout Europe while emerging criticalities and open research issues are presented

    Application of the LEED PRM to an Italian existing building

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    ANSI/ASHRAE/IESNA 90.1 Energy Standard for Buildings except Low-Rise Residential Buildings is the benchmark code of U.S. local regulations. In addition to provide a set of minimum mandatory requirements for energy-using components (prescriptive approach), the standard includes in the Appendix G a more flexible path to attest performances significantly better than code minimum (performance-based approach). With regard to this approach, a procedure to establish the proposed building performance by quantifying the energy savings above an annual baseline energy consumption is defined as Performance Rating Method and used within the Leadership in Energy and Environmental Design (LEED) Protocol. This paper applies the U.S. performance-based approach to the global energy efficiency goal within the prescriptive-oriented Italian framework. In particular, the Performance Rating Method – partially customized to the Italian context by GBC Italia¼ and in compliance with LEED Italia requirements – has been applied to an Italian case study in order to highlight strengths and weaknesses correlated to a steady adoption of the performance approach in Italian energy policies. The proposed building performance of the case study has been evaluated throughout a dynamic simulation analysis carried out by means of the EnergyPlus code

    Calibration of building energy simulation models based on optimization: A case study

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    This study applies an optimization-based approach for calibrating building energy models using monitored data. The calibration was carried out on a test building coupling the EnergyPlus energy simulation tool with the GenOpt optimization tool. The objective function was set to minimize the difference between simulated and monitored energy consumption. For evaluating the model accuracy, the Mean Bias Error (MBE) and the Coefficient of Variation of the \RMSE\ (Cv (RMSE)) were calculated and found consistent with \ASHRAE\ guideline 14 limits for a model to be considered calibrated

    Follow-up of patients with early breast cancer: Is it time to rewrite the story?

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    The guidelines for follow-up in breast cancer survivors support only performance of periodic physical examination and annual mammography. However, medical oncologists and primary care physicians routinely recommend both blood tests and non-mammographic imaging tests in asymptomatic patients, leading to an increased anxiety related to false-positive results and higher medical expenses. Recently, advanced imaging technologies have improved sensitivity/specificity to detect metastatic lesions before symptoms arise. Considering the progress made in the treatment of metastatic disease and the rapid evolution of targeted therapy, that requires customization of the strategy according to molecular characteristics of the disease, patients could derive real benefit to early detection of disease recurrence. This hypothesis must be tested in a prospective clinical trial

    PharmaCare 2018

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    [Italiano]: Il farmaco, nella sua accezione piĂč ampia e generale, puĂČ essere ritenuto un bene sociale, la cui valenza simbolica e curativa varia in relazione alla dimensione ambientale e culturale nel quale si inserisce. In tal senso, le prescrizioni farmaceutiche rappresentano un indicatore privilegiato per la conoscenza del sistema salute di un determinato territorio, poichĂ© costituiscono un punto di intersezione ideale tra la prospettiva medica e quella di mercato. Siffatte considerazioni hanno sollecitato l’elaborazione di questo Report che si pone, come obiettivi dichiarati, quello di essere uno strumento utile alla pianificazione di interventi di sanitĂ  pubblica, quanto quello di svolgere analisi approfondite sulle caratteristiche dei soggetti che usano i farmaci e sulle modalitĂ  di trattamento degli stessi, permettendo studi di appropriatezza prescrittiva su specifiche aree di rilevanza clinica e su specifiche coorti di soggetti. “PharmaCaRe Report 2018” Ăš stato realizzato dal CIRFF (Centro Interdipartimentale di Ricerca in Farmacoeconomia e Farmacoutilizzazione) dell’UniversitĂ  degli Studi di Napoli Federico II, in collaborazione con la Direzione Generale della Tutela della Salute della Regione Campania, per delineare un quadro dettagliato circa il consumo e la prescrizione dei farmaci in Campania nel 2018. Questo Report intende infatti fornire una fotografia dettagliata dell’utilizzo che, in Campania, viene fatto dei farmaci in termini di spesa, volumi e tipologia. Le analisi dei dati prodotte offrono spunti importanti per correlare la prevalenza delle patologie nel territorio con il corrispondente utilizzo dei farmaci e suggeriscono un’interpretazione dei principali fattori che influenzano la variabilitĂ  nella prescrizione. La disponibilitĂ  di una banca dati che copre una popolazione assistibile di circa sei milioni di abitanti Ăš d’altronde un potente strumento di ricerca per studiare gli effetti dell’utilizzo dei farmaci in condizioni di Real-World. La conoscenza delle dinamiche prescrittive, in termini qualitativi (appropriatezza d’uso), oltre che quantitativi (volumi di utilizzo) Ăš la condizione necessaria per inquadrare in un contesto razionale la politica del farmaco, anche sotto il profilo della valutazione degli effetti degli interventi che il mercato, le normative o la cultura del farmaco sviluppano nel tempo. Per tali ragioni, “PharmaCaRe Report 2018” rappresenta un utile quanto prezioso supporto ai decisori per individuare strategie volte a ottimizzare l’allocazione delle risorse, nonchĂ© migliorare i percorsi di cura attraverso un monitoraggio costante, la promozione di piĂč elevati standard di cura e l’uso sicuro, efficiente ed efficace dei farmaci ./[English]: In its broadest and most general sense, the drug can be considered a public resource, whose symbolic and curative value varies in relation to the environmental and cultural dimension in which it is embedded. In this sense, pharmaceutical prescriptions represent a privileged indicator for the knowledge of the health system of a given territory, since they constitute an ideal intersection point between the medical and the market perspective. Such considerations prompted the preparation of this Report. “PharmaCaRe Report 2018” has been produced by CIRFF (Centro Interdipartimentale di Ricerca in Farmacoeconomia e Farmacoutilizzazione) of the Federico II University of Naples, in collaboration with the Directorate-General for Health Protection of the Campania Region, to provide a detailed overview of the pharmaceutical consumption and prescriptions in Campania in 2018. This Report aims to provide a detailed picture of the use of medicines in the general population in Campania, in terms of expenditure, volumes and type. The analyses of the data produced offer important clues for correlating the prevalence of diseases in this area with the respective use of medicines and suggest an interpretation of the main factors influencing prescriptions' variability. The availability of a database covering a patient population of around six million is a powerful research tool for studying the effects of drug use in Real-World conditions. Knowledge of the dynamics of prescription, in qualitative terms (appropriateness of use), as well as quantitative (volumes of use) is the necessary condition to frame the drug policy in a rational context, also in terms of evaluating the effects of the interventions that the market, regulations or drug culture develop over time. For these reasons, “PharmaCaRe Report 2018” represents a useful and valuable tool for political decision-makers in identifying strategies aimed at optimizing the allocation of resources, as well as improving care pathways through constant monitoring, the promotion of higher standards of care and safe, efficient and effective use of drugs

    La calibrazione dei modelli di simulazione energetica. Metodologie ed applicazione ad un caso studio

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    In questo articolo vengono introdotte le metodologie di calibrazione dei modelli termoenergetici degli edifici, da quelli semplificati a quelli maggiormente dettagliati. Gli aspetti da considerare per effettuare la calibrazione di un modello riguardano l’identificazione dei parametri di input che maggiormente influenzano l’output del modello, i criteri da valutare e i parametri di soglia per poter considerare calibrato un modello. Infine la calibrazione di un caso studio ù descritta insieme all’approccio metodologico adottato
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