Daylighting Contribution for Energy Saving in a Historical Building

AbstractThe purpose of this study is assessing the reliability of the software DIALux 4.12 for daylighting design, comparing experimental data with simulation results; the comparison was performed for an office.The daylight illuminance distribution inside the room, the external zenith luminance and the external horizontal diffuse illuminance were measured during the weeks from January 19th to February 20th; the data gathered were further reduced to match conditions related to the CIE sky type #12 (CIE Standard Clear Sky, low luminance turbidity) and finally the comparison was carried in terms of daylight illuminance distribution and relative percentage error

Low-cost smart solutions for daylight and electric lighting integration in historical buildings

Research have shown that the correct integration of daylight and electric lighting reduces the energy use in buildings, while improving visual comfort. Smart shading systems, especially those electrically controlled, play an important role to control solar radiation. Similarly, smart and dimmable/tunable lighting can help to adjust the artificial light to the real users' needs. This paper presents preliminary results of an ongoing living lab study investigating how artificial lighting systems can be integrated with shading systems, placing human comfort at the heart of the study and yet saving energy. A manually controlled, commercial and low-cost smart system integrating two motorized shading devices and six dimmable LED luminaires with a different selection of CCT were installed in a private office in a historical building. Indoor and outdoor lighting conditions and energy consumption associated to the lighting system are constantly monitored to assess how the people use shading and lighting upon varying the boundary conditions.. Preliminary results highlight that users prefer to maximise daylight on the work plane as well as they generally use both shading and electric lighting systems in response to boundary conditions that cause serious discomfort

Energy Performances of Tensile Material in Building Renovation in the Nordic Region

Tensile materials are increasingly used in the building envelope as second-skin systems, despite a lack of investigation on their effects. In this work, a second-skin system integrating a tensile material as an outer layer has been adopted in the retrofit analysis of two of the most common building typologies in the Norwegian context. The simulations were carried out by implementing a custom control logic for the system, considering the outdoor air temperature and the global vertical irradiation on the façades. The proposed retrofit solution allowed for a primary energy saving of about 35%.publishedVersio

Experimental calibration and validation of a simulation model for fault detection of HVAC systems and application to a case study

Automated fault detection and diagnostics (FDD) could provide a cornerstone for predictive maintenance of heating, ventilation and air-conditioning (HVAC) systems based on the development of simulation models able to accurately compare the faulty operation with respect to nominal conditions. In this paper, several experiments have been carried out for assessing the performance of the HVAC unit (nominal cooling/heating capacity of 5.0/5.0 kW) controlling the thermo-hygrometric comfort inside a 4.0 × 4.0 × 3.6 m test room at the Department of Architecture and Industrial Design of the University of Campania Luigi Vanvitelli (Italy); then, a detailed dynamic simulation model has been developed and validated by contrasting the predictions with the measured data. The model has also been used to analyze the dynamic variations of key parameters associated to faulty operation in comparison to normal performance, in order to identify simplified rules for detection of any non-optimal states of HVAC devices. Finally, the simulated performance of the HVAC unit has also been investigated while serving a typical Italian building office with and without the occurrence of typical faults with the main aim of assessing the impact of the faults on thermo-hygrometric comfort conditions as well as electric energy consumption

Preliminary symptoms assessment of typical faults related to the fans and humidifiers of HVAC systems based on experimental data collected during Italian summer and winter

The symptoms associated to the occurrence of typical faults in a heating, ventilation and air-conditioning (HVAC) system, including a single duct dual fan constant air volume air-handling unit, have been experimentally characterized. The operation of the HVAC unit with 3 artificially forced faults ((1) reduced velocity of the supply air fan, (2) reduced velocity of the return air fan, (3) the valve supplying the humidifier kept always closed) has been analysed and compared with that of healthy operation of the same plant under very similar boundary conditions (outside air temperature and initial indoor air temperature) during Italian summer and winter in order to preliminarily assess (i) the effects on the main operating parameters, and (ii) generate preliminary operation data to assist further research in fault detection and diagnosis of HVAC systems

Healthy and Faulty Experimental Performance of a Typical HVAC System under Italian Climatic Conditions: Artificial Neural Network-Based Model and Fault Impact Assessment

The heating, ventilation, and air conditioning (HVAC) system serving the test room of the SENS i-Lab of the Department of Architecture and Industrial Design of the University of Campania Luigi Vanvitelli (Aversa, south of Italy) has been experimentally investigated through a series of tests performed during both summer and winter under both normal and faulty scenarios. In particular, five distinct typical faults have been artificially implemented in the HVAC system and analyzed during transient and steady-state operation. An optimal artificial neural network-based system model has been created in the MATLAB platform and verified by contrasting the experimental data with the predictions of twenty-two different neural network architectures. The selected artificial neural network architecture has been coupled with a dynamic simulation model developed by using the TRaNsient SYStems (TRNSYS) software platform with the main aims of (i) making available an experimental dataset characterized by labeled normal and faulty data covering a wide range of operating and climatic conditions; (ii) providing an accurate simulation tool able to generate operation data for assisting further research in fault detection and diagnosis of HVAC units; and (iii) evaluating the impact of selected faults on occupant indoor thermo-hygrometric comfort, temporal trends of key operating system parameters, and electric energy consumptions

DYNAMIC SIMULATION OF A SOLAR HEATING AND COOLING SYSTEM INCLUDING A SEASONAL STORAGE SERVING A SMALL ITALIAN RESIDENTIAL DISTRICT

A centralized solar hybrid heating and cooling system satisfying the thermal, cooling and sanitary water demands of a typical Italian small district composed of six residential buildings situated in Naples (southern Italy) is modelled, simulated and analysed through the software TRNSYS over a period of 5 years. The plant is based on the operation of solar thermal collectors coupled with seasonal borehole storage; the solar field is also composed of photovoltaic solar panels connected with electric energy storage. An adsorption chiller powered by solar energy is adopted for cooling purposes, while a condensing boiler is used as an auxiliary unit. The performance of the proposed system has been assessed from energy, environmental and economic points of view and contrasted with the operation of a typical Italian heating and cooling plant, highlighting the following main results: saving of primary energy consumption up to 40.2%; (decrease of equivalent CO2 emissions up to 38.4%; reduction of operating costs up to 40.1%; and simple pay-back period of about 20 years

Thermal Performance of an Electric-Driven Smart Window: Experiments in a Full-Scale Test Room and Simulation Model

This paper reports the results of experimental tests and numerical simulations aimed at evaluating the performance of an electric-driven smart window with respect to solar control in buildings. The experimental performances of the electric-driven smart window were evaluated using a south oriented full scale experimental facility designed and realized. The tests were carried out during the summer under real sky conditions upon varying the state of the electricdriven smart window (clear and milky). In the first part of the paper, the experimental results are discussed in terms of surface temperature of glazings as well as indoor air temperature in order to highlight the potential benefits on thermal comfort associated to the application of electric-driven smart windows. In the second part of this paper, the experimental data are compared to the numerical results generated through a simulation model of the electric-driven smart window in order to assess its reliability under different operating scenarios. Finally, the simulation model is used to quantify the potential cooling load reduction deriving from the integration of electric-driven smart windows in an office façade located in Naples (Italy)

Virtual reality for smart urban lighting design: Review, applications and opportunities

More and more cities are evolving into smart cities, increasing their attractiveness, energy efficiency, and users satisfaction. Lighting systems play an important role in the evolution process, thanks to their ability to affect city life at night along with people s mood and behaviour. In this scenario, advanced lighting design methods such as virtual reality (VR) became essential to assess lighting systems from different points of view, especially those linked with the city users expectations. Initially, the review highlights a list of objective and subjective parameters to be considered for the lighting design of three main city areas/applications: roads, green areas and buildings. Besides, the state-of-Art in using VR for outdoor lighting design is established. Finally, the Unreal game engine is used to analyse the ability of VR to take into account the lighting parameters, not yet investigated in current literature and to highlight the VR potential for augmenting lighting design. The results confirm the benefit of using VR in lighting design, even if further investigations are needed to establish its reliability, especially from the photometrical point of view