This study evaluates the effect of urban surfaces’ solar reflectance on the microclimate of a Brazilian city, Balneário Camboriú. A case study of two different geometrical areas of the city's central region was conducted. The influence of solar reflectance was evaluated through computer simulations on the ENVI-met model, validated for a winter and a spring day, according to field measurements. The simulations were performed for twelve combinations of solar reflectance on the roofs, façades, and pavements. The results confirmed that surfaces of high solar reflectance generally contribute to an air-temperature decrease. However, the degree to which each surface's solar reflectance influences the air temperature depends on the solar access (urban geometry, time, and season). In denser areas, the solar reflectance of facades has a greater impact on temperature variation, whereas in open spaces, roofing and paving surfaces are more critical. Impacts on urban microclimate extend beyond air temperatures. The radiation fluxes on two urban canyons revealed that the solar radiation incidence on the paving of a high solar reflectance canyon could be up to three times greater than one with low reflectance.

University campuses are comprised of many different types of buildings and thus, to improve their energy efficiency, the benchmarking of these buildings is fundamental. In this regard, this study aimed to develop an energy consumption benchmark for university buildings in Brazil. The benchmark was based on a database obtained through parametric building energy simulation by employing an archetype of a university building, developed by the Brazilian Council for Sustainable Construction (CBCS), and a set of parameter variations. The database was obtained considering nine building parameters (e.g., occupancy, internal loads and envelope features), resulting in 23,256 cases aimed at representing the variety of university buildings countrywide. Therefore, this process is innovative since a benchmark is developed for multiple buildings across the country rather than for only one building on a specific university building or campus. Three machine learning techniques were compared to develop the benchmark, multiple linear regression (MLR), support vector machine (SVM) and artificial neural network (ANN). The SVM method had the lowest mean absolute error, root mean absolute error and the highest R2 value, and thus it was adopted to develop the benchmark and efficiency scales. The efficiency scale was used to classify the buildings into ‘efficient’, ‘typical’ or ‘inefficient’, and supports the identification of good practice or inefficiency.

The use of low-emissivity materials in roofing offers a low-cost solution to reduce the demand for cooling in countries with hot climates. The performance of radiant barriers is often evaluated through simulations and the type of modeling employed influences the results. This study evaluates different modeling approaches to simulate radiant barriers in attics. First, the influence of the temperature and emissivity of materials on the thermal resistance of air chambers were evaluated. Then, the heat flow and thermal load values were obtained with the simulation of three different models. Simulation results were compared with actual tests and results in the literature. The emissivity of the materials resulted in strength variations of up to 4%. The simulation model that adopted the energy management system (EMS) and thermal resistance calculated according to ISO 6946 2017 was the closest results to experimental tests and literature. These provide maximum differences of 7% in the downward heat flow and thermal load. The model that included the attic underestimated by 20% the reduction in heat flow compared to bench tests. Finally, thermal resistance values to be adopted in attic simulations with low-emissivity materials in hot climates are proposed.
 

Occupant-centric building design and operation has attracted recent research efforts in many countries, as building occupants are being more recognized as the main drivers in planning and operating safe, comfortable, energy-efficient indoor environments. In this matter, the role of building managers and operators is crucial to capture the needs of occupants and to adapt the response of the building accordingly. IEA EBC Annex 79 participants conducted 72 interviews with operators and facility managers across 7 countries (Brazil, Canada, Germany, Italy, Poland, Singapore, and USA) covering a wide range of ASHRAE 169 climate zones (from 0 to 5 in the climate classification). This paper presents a qualitative cross-case analysis of operators’ perspectives and experiences to identify regional differences. Therefore, the analyses are based on the hypotheses that climate or other country-related aspects would be the main drivers of building operation procedures differences. Results show climatic differences have little influence on building management, while occupants' complaints are very influenced by them. Moreover, operators are lacking clear tools, like guidelines and standards, on how to optimize building management in a climatic-adaptive and occupant-centric manner. Therefore, the development of operation protocols for building sustainable operation respecting climatic context and occupants’ control is recommended.