Papers by Annamaria Belleri
Modelling of A Complex Building in Norway
Building Simulation Conference proceedings, Dec 7, 2015
Modelling of A Complex Building in Norway
Building Simulation Conference Proceedings
Building Simulation Conference Proceedings
The 9th Annual Edition of Sustainable Places (SP 2021), 2021
The building sector plays an important role in the transition to a climate-neutral society. The i... more The building sector plays an important role in the transition to a climate-neutral society. The international interest in low, zero energy, or zero-emission buildings has grown as a potential means for this transition. A more ambitious step from zero energy buildings is the concept of Positive Energy Buildings (PEB), which are also contributing to the decarbonization of the surrounding built environment, not just minimizing their own carbon footprint. A shared PEB definition is needed in order to enable the design, assessment, and documentation of positive energy buildings. This article describes the ongoing discussions, concentrating on the most essential points.
Ventilative cooling strategies to reduce cooling and ventilation needs in shopping centres
Because of the customer need of best possible comfort condition and satisfaction, shopping center... more Because of the customer need of best possible comfort condition and satisfaction, shopping centers are conditioned by means of basic HVAC systems, often without considering the potential of natural ventilation to contribute to air change rate, and to reduce the cooling demand. Mechanical ventilation systems are also preferred to natural ventilation because more controllable and reliable since they are not affected by the uncertainty of natural forces. However, atriums or in general common areas within a shopping center can suite the ventilative cooling purpose. In fact, on one hand they present more relaxed ranges of interior conditions respect to retail zones and, on the other hand, they can exploit the airflow driven both by thermal buoyancy and by wind pressure because of the big volumes involved. The use of ventilative cooling strategies can be beneficial in reducing both cooling demand and electricity consumption for ventilation. The paper investigates the feasibility of ventil...
In recent years, concerns about global warming and greenhouse gas emissions have motivated design... more In recent years, concerns about global warming and greenhouse gas emissions have motivated designers to reduce building energy consumption through the implementation of passive solutions without compromising users’ thermal comfort. This evidence has stimulated a renewed interest in designers for the exploitation of natural ventilation as means of passive cooling solutions. The adoption of ventilative cooling is particularly suitable for large spaces (non-residential buildings) as a measure to reduce the HVAC system high cooling loads. Due the inability to control and ensure a constant airflow rate through natural ventilation most of the times designers choice goes towards mixed-mode buildings. Mixed-mode buildings are designed in such a way that the HVAC system acts as backup to prevent uncomfortable conditions when natural ventilation is not sufficient to guarantee a comfortable environment. Unfortunately, information about the actual performance of mixed-mode buildings is difficul...
Nearly all retail locations use mechanical cooling systems to ensure indoor comfort temperatures ... more Nearly all retail locations use mechanical cooling systems to ensure indoor comfort temperatures and mechanical ventilation to ensure adequate air exchange, primarily for hygienic reasons. Because of the big volumes involved and the lack of knowledge in natural ventilation design, shopping centres designers have been relying on basic HVAC equipment, without considering the potential of ventilative cooling to reduce cooling needs and to maintain an acceptable indoor environmental quality. The CommONEnergy FP7 project investigated the retrofit opportunities to exploit ventilative cooling in shopping centres’ common areas (shop galleries and atria) considering external climate conditions and architectural features. The paper presents the development and demonstration of a ventilative cooling strategy in the demo case located in Trondheim (Norway). The strategy combines the effect of opened sliding doors and skylight openings to enhance stack ventilation and ventilate/cool the common ar...
E3S Web of Conferences, 2019
Despite a wide range of energy-efficient technologies, financial products and public incentives a... more Despite a wide range of energy-efficient technologies, financial products and public incentives are already available, the private as well as the public sector are struggling to invest in energy efficient solutions for buildings. The primary barriers are the high initial cost and the uncertain payback period of the energy refurbishment. Allowing for different scenario testing and considering interactions among different building energy systems, building energy simulation tools can help investors overcoming such barriers by offering support to the technical planning of energy refurbishment kits through quantitative information rather than qualitative. The energy performance and comfort of three reference multifamily residential buildings typologies were evaluated considering three envelope retrofitting performance levels (high-medium-low insulated and airtight) and different heating and domestic hot water systems (heat pump, boiler, district heating). The tested envelope retrofitting...
International Journal of Ventilation, 2017
The ventilative cooling potential tool (VC tool) aims at assessing the potential effectiveness of... more The ventilative cooling potential tool (VC tool) aims at assessing the potential effectiveness of ventilative cooling strategies by taking into account also building envelope thermal properties, occupancy patterns, internal gains and ventilation needs. The analysis is based on a singlezone thermal model applied to user-input climatic data on hourly basis. For each hour of the annual climatic record of the given location, an algorithm identifies over the occupied time the number of hours when ventilative cooling is useful and estimates the airflow rates needed to prevent building overheating. As validation of results, the ventilative cooling potential tool outputs are compared with the predictions of a building energy simulation model of a reference room in two different climates. The VC tool is particularly suitable for early design phases, providing building designers with useful information about the level of ventilation rates needed to offset given rates of internal heat gains.
Within the research project "IEA SHC Task 40 -ECBCS Annex 52: Towards Net Zero Energy Solar Build... more Within the research project "IEA SHC Task 40 -ECBCS Annex 52: Towards Net Zero Energy Solar Buildings" an excel-based tool was developed to assess balance, operating costs and load match index for predefined selected Net ZEB definitions . The tool can be of assistance for different stakeholders, including building designers (evaluation of building design solutions with respect to different Net ZEB definitions), energy managers (assess the balance in monitored buildings) and policy makers (assist in the upcoming implementation process of Net ZEBs within the national normative framework). Starting from the known general definition of a Zero Energy Building, several definitions can be generated by choosing different options for the main available aspects (e.g., building system boundaries, weighting system, energy balance calculation) and translated into different yearly energy balances as illustrated by Sartori et al. (2012) [2]. The Net ZEB evaluation tool includes four Net ZEB definitions [1] which have been selected by the project participants because they were considered to be the most likely to be applied to both design and monitored building data and to include calculation factors and methodologies already available or close to their finalization . The main worksheet of the workbook is the 'building data' used to collect input data for building monthly/yearly energy demand/supply; subsequently, the desired weighting factors can be specified. Balance calculation can be performed both in static (yearly based) and quasi-static (monthly based) mode by providing static or semi-static weighting factors to convert the final energy into the metrics considered in the selected definitions (primary energy, CO 2 equivalent emissions or a userdefined metric) and calculate the balance . The authors are part of the IEA SHC Task 40 -ECBCS Annex 52 project national experts and are applying the methodology developed to propose a Net ZEB definition at local level (province of Bolzano, Italy). The pilot building of the new Technology Park of Bolzano was selected as demonstrator. For this application, the target Net ZEB has been fixed by choosing the following definition: 'a building, fulfilling any national and local energy efficiency requirements, which offsets the yearly balance between exported and delivered energy, weighted in terms of primary energy and/or equivalent carbon emissions. Static and symmetric weighting factors are applied to convert the exported/delivered energy carriers in the balance metric (primary energy and/or equivalent carbon emissions). All the energy uses of the building, or the energy uses of the buildings located inside the physical boundaries, are considered as negative balance items (heating, DHW, cooling, indoor lighting, auxiliaries, ventilation and plug loads). As positive balance item, only the on-site generation
Despite a lot of Integrated Design Process guidelines and procedures have been developed in the l... more Despite a lot of Integrated Design Process guidelines and procedures have been developed in the last few years, more specific energy design procedures are needed to push the implementation of passive design techniques. As natural ventilation design influences strongly the building shape and aspect, it has to be considered since the early design stages and its effect should be correctly predicted and proved by means of suitable tools and methods. In this respect, airflownetwork models seems a promising modelling techniques as they are already integrated in the existing dynamic building simulation tools and they have a quick solver. On the other hand, the simplicity of these models implies uncertainties in a lot of input parameters, first of all the wind conditions. The urban wind environment is a stochastic phenomenon, and as consequence the ventilation performance in a naturally ventilated building changes. An accurate wind analysis should be supported by weather data collected on site and by an external CFD simulation at urban scale. Discharge coefficients and external convection coefficients could be accurately estimated by laboratory tests. This would mean additional design costs (and time) and need of expertise in the field. A key issue of this work is to assess the thermal-airflow model reliability in airflow prediction when accurate estimation of input data is not feasible. This paper presents an uncertatinty analysis performed on a dynamic simulation model of a new office building naturally ventilated during the night. Full-factorial parametric analysis have been performed to assess the influence of the input parameters on the model reliability. Possible input ranges have been estimated and organized in a tree-structure to investigate the effect of dependent parameters like wind velocity profile, wind pressure coefficients, discharge coefficients, and external convection coefficients. Significant variations in air change rates are shown that reflect an uncertainty of +/-2% on total cooling loads in respect to the base case simulation result. No direct correlations between outdoor environmental conditions and air change rates have been found as the discharge coefficients affect significantly the results. The design proposal supported by quantitative analysis and results prediction uncertainty assessment can be taken into consideration more seriously by the design team. The obtained results can be generally extended to airflownetworks with similar airflow paths.
Natural ventilation is increasingly considered a promising solution to improve thermal comfort in... more Natural ventilation is increasingly considered a promising solution to improve thermal comfort in buildings, including schools. However in order to support its planning and implementation, quantitative analysis on airflow paths and heat-airflow building interactions are needed. This requires an adequate accounting of both internal effects, from building layout and structure, and external forcings from atmospheric factors. The paper analyses the performances of natural ventilation strategies as retrofit solutions to improve thermal comfort in an existing school building in Lavis (Trento, Italy). A climatic analysis is performed to define the potential of wind driven natural ventilation. Meteorological data collected on site are analysed to identify typical wind conditions during the cooling season. The resulting daily cycle of wind speed and direction in sunny days reflects the typical dynamics of a regular valley wind, but also displays the peculiar characteristic of being strongly ...
Short Summary The paper in the beginning clarifies what the nearly Zero Energy Building (nZEB) me... more Short Summary The paper in the beginning clarifies what the nearly Zero Energy Building (nZEB) means and what the advantages of an Integration Energy Design (IED) process are. Afterwards, it shows two local experiences about nearly zero energy target integration in two different public design tenders procedures. The first experience regards a restricted design competition which aims at finding the best design proposal within a restricted number of projects. While the second experience regards a negotiated design tender which just aims at selecting the design team will design the new public building. Results show how to integrate, require and evaluate the results of different tender procedures, advantages to use IED process.
We present a study of natural ventilation design during the early (conceptual) stage of a buildin... more We present a study of natural ventilation design during the early (conceptual) stage of a building's design, based on a field study in a naturally ventilated office in California where we collected data on occupants' window use, local weather conditions, indoor environmental conditions, and air change rates based on tracer-gas decay. We performed uncertainty and sensitivity analyses to determine which design parameters have most impact on the uncertainty associated with ventilation performance predictions. Using the results of the field study along with wind-tunnel measurements and other detailed analysis, we incrementally improved our early-design-stage model. The improved model's natural ventilation performance predictions were significantly more accurate than those of the first draft early-stage-design model that employed model assumptions typical during initial design. This process highlighted significant limitations in the EnergyPlus software's models of occupant-driven window control. We conclude with recommendations on key design parameters including window control, wind pressure coefficients and weather data resolution to help improve early-design-stage predictions of natural ventilation performance using EnergyPlus.
A shopping centre is a building, or a complex of buildings, designed and built to contain many in... more A shopping centre is a building, or a complex of buildings, designed and built to contain many interconnected activities in different areas. Shopping centres have special peculiarities as they vary in their functions, typologies, forms and size. Within the retail sector, they are of particular interest because of their structural complexity and multi-stakeholders' decisional process, their high energy savings potential and carbon emissions reduction, as well as their importance and influence. In order to efficiently exploit a shopping centre energy potential, every retrofitting should involve a careful analysis of the building peculiarities in all fields, from the economic features to the sociocultural ones. The use of building energy simulations can help evaluate the balance between gains and losses and the energy uses and test design options and solution-sets. The CommONEnergy guidelines are a step-by-step handbook for the renovation of shopping centres, resulting from the four years of research of the project. Starting from an analysis of shopping centres' features and drivers for their renovation, CommONEnergy guidelines go through processes, modelling and tools developed by the project, focusing in particular on the several technologies enabling the aggregation in cost-effective solution-sets, like greenery integration, multifunctional coating and demand-response approach for refrigeration. The tools described by the guidelines include the Economic Assessment Tool and the Integrated Design Process Library.
We present a study of natural ventilation design during the early (conceptual) stage of a buildin... more We present a study of natural ventilation design during the early (conceptual) stage of a building's design, based on a field study in a naturally ventilated office in California where we collected data on occupants' window use, local weather conditions, indoor environmental conditions, and air change rates based on tracer-gas decay. We performed uncertainty and sensitivity analyses to determine which design parameters have most impact on the uncertainty associated with ventilation performance predictions. Using the results of the field study along with wind-tunnel measurements and other detailed analysis, we incrementally improved our early-design-stage model. The improved model's natural ventilation performance predictions were significantly more accurate than those of the first draft early-stage-design model that employed model assumptions typical during initial design. This process highlighted significant limitations in the EnergyPlus software's models of occupant-driven window control. We conclude with recommendations on key design parameters including window control, wind pressure coefficients and weather data resolution to help improve early-design-stage predictions of natural ventilation performance using EnergyPlus.
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Papers by Annamaria Belleri