124 research outputs found
Causal Modelling Based on Bayesian Networks for Preliminary Design of Buildings
Bayesian networks are a very general and powerful tool that can be used for a large number of problems involving uncertainty: reasoning, learning, planning and perception. They provide a language that supports efficient algorithms for the automatic construction of expert systems in several different contexts. The range of applications of Bayesian networks currently extends over almost all fields including engineering, biology and medicine, information and communication technologies and finance. This book is a collection of original contributions to the methodology and applications of Bayesian networks. It contains recent developments in the field and illustrates, on a sample of applications, the power of Bayesian networks in dealing the modeling of complex systems. Readers that are not familiar with this tool, but have some technical background, will find in this book all necessary theoretical and practical information on how to use and implement Bayesian networks in their own work. There is no doubt that this book constitutes a valuable resource for engineers, researchers, students and all those who are interested in discovering and experiencing the potential of this major tool of the century
Development and calibration of a model for the dynamic simulation of fans with induction motors
In this paper a model for the dynamic simulation of fans used in mechanical air supply systems is
described. Thanks to this model, the behavior of fans subject to control by variable frequency drives
(VFD) can be predicted, which includes power absorbed by the fan and expected ventilation rates.
Hence, it can help design energy control systems for buildings. The proposed model was based on the
Modelica language and was developed from the dynamic phasor domain representation, because this
representation is a trade-off between the basic non transient representation, that is computationally efficient
but cannot describe fan dynamics, and the dynamic time domain model, that is the most representative
one but computationally very demanding. A comparison among these models showed that, within
fan frequency variations typical of ventilation systems in buildings, the phasor domain model is as representative
as the more complex dynamic time domain model in terms of prediction of the dynamic
behavior, that is neglected by the basic non transient model. Moreover, the new phasor domain model
was validated against measured data relative to a fan installed in a subway station in Barcelona.
Thanks to this model, energy consumption of dynamically driven fans can be estimated at the simulation
stage, at the expense of a reasonable computational effort
Numerical Approach for the Design of Cost-Effective Renovation of Heating System Control in Buildings
This chapter focuses on advanced tools for transient energy simulation of existing buildings. Budget constraints often hinder the possibility of implementing large-scale retrofit projects. As a consequence, designers must work out low-cost renovation, which asks for a deep knowledge of the current state of the buildings. Furthermore, the performances of heating plants in existing buildings can be enhanced through the improvement of the control of the system. These types of retrofit actions can be carried out with a limited budget, but asks for the availability of very accurate transient energy simulation tools, which can compare the current and the renovated scenarios. On top of them, cost–benefit analyses can be developed. In this chapter, a model of a small hospital is developed in the Dymola/Modelica environment. The high flexibility of the transient simulation model and the very good agreement between numerical estimations and measurements are shown. Then, one scenario regarding enhanced regulation of the heating system by means of a customized ambient temperature control system is developed, and the expected energy savings are estimated
Evaluation of energy conservation opportunities through Energy Performance Contracting: A case study in Italy
Non-residential buildings like healthcare ones contribute to energy consumption and cause a negative environmental impact. This is mainly due to the age of the buildings, their poor level of energy efficiency and the implementation of only a basic maintenance plan. Owing to the very limited budget available for public administrators, Energy Performance Contracting (EPC), that entails the involvement of an Energy Service Company (ESCo), can provide the entire or part of the capital needed for investments aimed at progressively increasing energy efficiency over their service life. In this paper, three acute hospitals and two community clinics built in Italy are analysed, in order to assess the economic feasibility of several energy renovation actions that can be included within EPC contracts. To this purpose, the outcomes of energy audits carried out in 2014 about these buildings are reported, which involved analyses of consumption measured over the previous three years and assessment of use profiles for the development of models to break down the overall consumption and to estimate potential savings. Diverse improvement strategies were assessed, consisting in either isolated or combined renovation actions and tested on the five buildings, whose comparison was carried out in terms of energy saving, pollution reduction and economic feasibility. As a result, the best combined renovation actions per each hospital were recommended, that included - but were not limited to - the improvement of the control and regulation of existing sub-systems without replacement, partial replacement of other sub-systems and integration of renewables. Finally, each scenario was evaluated through the payback period and other economic performance indexes in order-to assess the feasibility of the EPC framework when applied to this case study
Managing Energy Retrofit of Acute Hospitals and Community Clinics through EPC Contracting: The MARTE Project
Abstract Acute hospitals and community clinics contribute to energy consumption and have a negative environmental impact. This is mainly due to the age of the buildings, a poor level of energy efficiency and a basic maintenance plan. Owing to the very limited money available for public administrators, Energy Performance Contracting (EPC), involving an Energy Service Company (ESCo), can provide the capital needed for investments aimed at increasing energy efficiency. In this paper three acute hospitals and two community clinics in Italy are analyzed prior to EPC development in order to assess the economic feasibility of retrofit strategies. The outcome of energy audits carried out in 2014, the analyses of consumption measured over the last 3 years, and the assessment of use profiles were all considered for the development of models to break down the overall consumption and to assess potential savings. Recommended improvement strategies include better insulation in envelopes, enhancement of mechanical and lighting equipment, use of renewable energy, better regulation of systems. Finally, payback periods for the most likely scenarios were evaluated
Augmented Reality Application Supporting On-Site Secondary Building Assets Management
none5sinoneA. Corneli, B. Naticchia, A. Carbonari, F. Bosché, L. PrincipiCorneli, A.; Naticchia, B.; Carbonari, A.; Bosché, F.; Principi, L
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