Savings related to solar water heating system: A case study of low-income families in Brazil

Autores:
Thalita Giglio; Roberto Lamberts
Evento:
Energy and buildings
Resumo:

The inclusion of solar water heaters available through subsidies of the Brazilian government has benefited more than 300,000 low-income families. Although these subsidies are important for wide implementation of this technology, the actual system performance is unclear. Moreover, it is unclear whether the performance is affected by user behavior in the context of complex socioeconomic issues. The objective of this research is to assess the influence of human behavior on the potential savings induced by solar water heaters. The research strategy integrated qualitative and quantitative measurements. We applied the cluster analysis technique to identify five homogeneous subgroups for a case study in Londrina, Brazil, in which a detailed measurement procedure was implemented to gather data on these subgroups over one year. The measurements were conducted to gain a better understanding of the factors affecting electricity consumed by showering. This study shows that the benefits of solar heaters vary according to the user and use of the technology. The annual energy savings averaged 9.51–18.6 kWh per person. A lack of technological understanding and the difficulty in effectively mixing hot and cold water were the main factors contributing to the inefficient use of the system.

Ano:

Building energy efficiency: An overview of the Brazilian residential labeling scheme

Autores:
Michele Fossati; Veridiana Atanasio Scalco; Vinícius Cesar Cadena Linczuk; Roberto Lamberts
Evento:
Renewable and Sustainable Energy Reviews
Resumo:

One of the alternatives to reduce building energy consumption recognized and used internationally is establishing standards for the evaluation and classification of buildings in terms of energy performance. In developed countries, the introduction of energy efficiency codes for residential and non-residential buildings started around the time of the first oil crisis in the mid-70s. Ten years later, Brazil has started implemented measures aimed at the conservation and rational use of energy. Initiatives in this regard began with the implementation of the Brazilian Labeling Program, where consumers are provided with information on the energy efficiency of appliances. However, the first energy efficiency law stimulated the most notable improvement in energy efficiency in 2001 after national energy crisis. As a result, the Regulation for Energy Efficiency Labeling of Commercial, Service and Public Buildings (RTQ-C) was released in February 2009 and the Regulation for Energy Efficiency Labeling of Residential Buildings (RTQ-R) was released in November 2010. Nowadays, the labeling of residential, commercial and service buildings is voluntary and the labeling of federal public buildings is mandatory since 2014. This paper presents a review of the building energy efficiency codes and labeling schemes all over the world, an overview of the Brazilian regulations on energy efficiency and discusses the labeling scheme for residential buildings adopted in Brazil. The process of its implementation, strengths and weaknesses in the present labeling scheme and the similarities and differences in relation to international experiences are described. The results obtained to date indicate that a revision is required in order to achieve a more flexible and economically viable process that will enable the program to be established as compulsory.

Ano:

Evaluating energy performance in non-domestic buildings: A review

Autores:
E. H. Borgstein; R. Lamberts; J. L.M. Hensen
Evento:
Energy and buildings
Resumo:

Evaluation methods can be used to determine what constitutes good energy performance in a building. With an increasing focus on energy use of buildings worldwide, this evaluation assumes a fundamental importance. This paper provides a comprehensive review of the available methods for analysing, classifying, benchmarking, rating and evaluating energy performance in non-domestic buildings.

Methodologies are grouped in five categories: engineering calculations, simulation, statistical methods, machine learning and other methods. Techniques for evaluating buildings are described, their principal applications are shown and limitations are identified. The use of performance evaluation in energy efficiency programmes and standards is mapped.

There is a need to further develop interactions between the main modelling techniques to produce simple, robust and validated models. Also, evaluation techniques must be developed to consider comfort or service provision in the buildings as a factor in energy performance.

Ano:

Should we consider climate change for Brazilian social housing? Assessment of energy efficiency adaptation measures

Autores:
Maria Andrea Triana; Roberto Lamberts; Paola Sassi
Evento:
Energy and buildings
Resumo:

Social housing sector is very important in Brazil, due to the necessity of expansion and investments being placed through a substantial government program. Residential buildings are expected to last at least 50 years according to Brazilian standards. Many residential projects in the sector already perform medium or poorly in terms of energy efficiency and thermal comfort today, and their designs are not analysed considering climate change. Therefore, the aim of this paper is to investigate the result of analysing the thermal and energy performance of social housing projects considering climate change, and to assess the impact on the operational phase of introducing energy efficiency measures in the sector, and exploring methods of adaptation to climate change. A representative project of the lower income sector housing was used as case study with the evaluation of measures through thermal and energy simulation with current and future weather files for the cities of São Paulo and Salvador. Results were compared using predicted energy consumption and cooling and heating degree-hours as indicators. The results highlighted some differences related to the climate scenarios and indicator analysed, and showed that the incorporation of energy efficiency measures in current social housing projects is of fundamental importance to minimize the effects of climate change in the coming decades.
 

Ano:

Analyzing the impact of small solar water heating systems on peak demand and on emissions in the Brazilian context

Autores:
T. Giglio; V. Santos; R. Lamberts
Evento:
Renewable Energy
Resumo:

This study presents a methodology to measure the impact of solar heating systems, on reducing peak demand and on avoided emissions, when applied in low-income housing projects. To this end, a real-time monitoring system was implemented over a year in five clusters representative of a heterogeneous socioeconomic context in new housing subsidized with solar water heating system through the national program “My House, My Life”. The results showed an expressive contribution of the system in reducing the maximum peak demand, obtaining, on average, a 64% reduction in relation to the electric showerhead, predominantly used in the country. The cumulative energy savings of 577 kWh per year resulted in an average of 250 kgCO 2 avoided per housing unit. The extrapolation of the data to 224,000 units already delivered by the national program would result in an economy of 56,089 tCO 2 per year. This study demonstrates the importance of measurement as a strategic tool in public policies for energy efficiency and in the estimation of emissions associated with greenhouse gases. The solar heating system positions itself as an important energy efficiency policy for Brazil, which minimizes the demand for thermoelectric plants during peak hours and postpones investments with new power generation plants.
 

Ano:

A review of occupant behaviour in residential buildings

Autores:
Bruna Faitão Balvedi; Enedir Ghisi; Roberto Lamberts
Evento:
Energy and buildings
Resumo:

Occupant behaviour has a direct impact on building energy consumption. A better understanding of human-building interactions enables to describe with higher accuracy the occupant behaviour. This paper addresses occupant behaviour in residential buildings, providing a review of current methods in (1) monitoring occupant behaviour, (2) developing occupant behaviour models, and (3) applying occupant behaviour models in building performance simulations. Occupant behaviour studies with focus on residential buildings are presented including both challenges and potential for improving building energy performance.

Ano:

Residential solar water heaters in Brisbane, Australia: Key performance parameters and indicators

Autores:
Abel S. Vieira; Rodney A. Stewart; Roberto Lamberts; Cara D. Beal
Evento:
Renewable Energy
Resumo:

A multi-parametric sensitivity analysis of Solar Water Heater (SWH) systems was undertaken for the city of Brisbane in Australia using computational models calibrated by experimental data. The models were calculated using EnergyPlus 8.6. The following technical specification parameters were assessed in the modelling: (i) solar collector efficiency; (ii) solar collector area; (iii) tank volume; (iv) tank heat loss; (v) electric back-up heating power rate; (vi) electric back-up heating position (height) for vertical tanks; and (vii) electric back-up heating temperature range. The site-specific parameters included: (i) solar collector direction; (ii) solar collector tilt angle; (iii) solar collector shadowing; (iv) solar collector dust accumulation; (v) hot water pipe insulation; (vi) hot water pipe length; (vii) electricity tariff time-of-use; and (viii) cold water temperature. User behaviour patterns were comprised of the following parameters: (i) end-use water temperature; (ii) end-use water demand; and (iii) end-use time-of-use. For all parameters, two system types were assessed, namely: (i) thermosiphon systems with natural (passive) circulation in collectors and unstratified horizontal hot water storage tanks; and (ii) split systems with forced (pumped) circulation in collectors and stratified vertical hot water storage tanks. The performance of SWHs was analysed considering both energy performance indicators (i.e. total and peak-hour energy consumption, solar fraction and energy intensity) and level of service indicators (i.e. compliance with recommended hot water temperatures for Legionella spp. control and comfort levels). Notwithstanding the prevalence of thermosiphon systems among SWH technologies, results indicate that split systems usually outperformed thermosiphon systems both in terms of energy efficiency and level of service, and hence should be a preferred option for energy efficiency initiatives and policies.

Ano:

Technological innovations to assess and include the human dimension in the building-performance loop: A review

Autores:
Mateus Vinícius Bavaresco; Simona D'Oca; Enedir Ghisi; Roberto Lamberts
Evento:
Energy and buildings
Resumo:

The human dimension plays an essential role in the energy performance of buildings and is considered as significant as technological advances. Several studies highlighted the negative influence of occupant behaviour in underperforming buildings, while some support that technological innovations may reduce human-related uncertainties. Thus, one may consider that fully automated smart buildings are essential to achieve energy efficiency. However, if technology excludes people from decision-making processes, low acceptance and comfort/welfare levels may be reported from users. Therefore, the right combination of humans and technologies are expected to solve these problems. Buildings are emerging as complex Cyber-Physical Systems, including the Social dimension, and this provides an excellent opportunity to achieve high-performance outcomes, considering both technical and social aspects. Thus, the right choice among available up-to-date behavioural sensing – comprising active and passive sensors, as well as Kinect technology – are important in the Internet-of-Things (IoT) era. IoT-driven buildings can use real-time monitoring data to inform users and drive behavioural-based consumption change, which is an important aspect to achieve high-performance buildings and deliver user-centred services. An essential feature in this regard is to allow for human-in-the-loop approaches enabled by human-centric computing and smart devices, which has grown fast in the last few years. This literature review summarises applications and main challenges related to the combination of the human dimension and technological innovations in the building sector. This combination is expected to increase user welfare and reduce the energy consumption in buildings, as human and machine components of intelligence may complement each other regarding building performance.

Ano:

Methods used in social sciences that suit energy research: A literature review on qualitative methods to assess the human dimension of energy use in buildings

Autores:
Mateus V. Bavaresco; Simona D'Oca; Enedir Ghisi; Roberto Lamberts
Evento:
Energy and buildings
Resumo:

Different stakeholders are involved in the energy consumption in buildings: occupants, designers, managers, operators, policymakers, technology developers and vendors. Therefore, it is necessary to understand their opinions and needs to optimise the energy consumption in buildings during their lifespan. Questionnaires and interviews have been applied; however, the literature still supports that energy research lacks social science approaches to improve their outcomes. Although limitations are inherent in qualitative methods (e.g., social desirability bias), much information such as human needs, preferences and opinions cannot be obtained through quantitative methods like building monitoring. Therefore, to have a deeper understanding of human-related aspects regarding the energy consumption in buildings, this literature review synthesises opportunities and main challenges of applying methods commonly used in social sciences. We reviewed papers published over the last five years (from 2014 to 2019) and presented information about questionnaires, interviews, brainstorming, post-occupancy evaluation, personal diaries, elicitation studies, ethnographic studies, and cultural probe. Increasing use of qualitative methods is expected to support the spread of human-centric policies and design/control of buildings, with a consequent overall optimisation of energy performance of buildings as well as the comfort of occupants.

Ano:

ANÁLISE DOS PARÂMETROS DE ENTRADA PARA A PREDIÇÃO DA CARGA TÉRMICA DE UMA RESIDÊNCIA MULTIFAMILIAR ATRAVÉS DA NOVA PROPOSTA DO REGULAMENTO BRASILEIRO DE ETIQUETAGEM

Este trabalho apresenta uma análise de sensibilidade dos parâmetros de entrada considerados no método simplificado da nova proposta para a Instrução Normativa Residencial do INMETRO (INI-R). A escolha da edificação do estudo foi realizada utilizando um levantamento estatístico das tipologias mais frequentes no programa do governo federal brasileiro “Minha Casa Minha Vida”. A tipologia em formato H adotada foi analisada nos climas de São Paulo (SP), Cuiabá (MT), Salvador (BA) e Manaus (AM).

Inscrever-se em