2.1.4. Building Energy Simulation Tools

There is indeed a vast amount of available computational tools for building energy simulation purposes. IBPSA-USA has developed and manages the so-called Building Energy Software Tools (BEST) directory [33], which enlists more than 200 building software tools for evaluating building energy performance. The energy tools listed in the directory range from simple databases and spreadsheets to whole building energy simulation programs. In agreement with other review studies [15,34], the current paper focuses on the most popular tools used mainly for whole building energy performance assessments regarding at least commercial and residential buildings. In the following subsections, a short overview of each tool's capabilities is reported, supported by a summary of their characteristics presented in Table 2.


**Table 2.** Strengths, weaknesses, and special features of computational building energy simulation tools.

**Table 2.** *Cont.*


**Table 2.** *Cont.*



**Table 2.** *Cont.*

The tools of interest herein are:


control


Autodesk Green Building Studio

The Autodesk Green Building Studio is a web-based service that envisages whole building energy, water resources, and CO2 emission analyses of buildings. The analysis is conducted via the Internet in a personalised web environment. This streamlines the entire setup process and facilitates immediate feedback on design alternatives. Based on the building's basic characteristics, such as size, type, and climate zone, the web-based service defines default values for construction materials and equipment by adopting regional building regulations. Using simple drop-down menus, the user can test different settings of the design, orientation, thermal transmittance, window glazing, or various HVAC systems. The service includes hourly weather data, as well as historical rain data as inputs. It calculates carbon emissions and presents the output in a web browser, for instance, the energy consumption and cost indicators as well as the potential for carbon neutrality. The output also tabulates the consumption of water resources and energy costs, providing an ENERGY-STAR score. Other useful indicators are also calculated such as solar and wind energy potential, LEED daylighting credit, and natural ventilation potential.

Najjar et al. (2017) [35] used the software in the case of a typical multi-storey office building located in Brazil in the framework of Building Information Modelling (BIM)—Life Cycle Analysis (LCA) simulation concept. In their modelling approach they incorporated Green Building Studio (GBS) to assess building energy performance for different construction materials. In a design control volume extending from the extraction of raw materials through construction and operation to disposal and recycling, they demonstrated that most of the negative environmental impacts are occurring during the manufacturing and operation phases. The methodology proposed can successfully determine which building elements have major importance in the LCA at the early design stage, thus providing an adequate decision-making tool for minimizing buildings' environmental impacts throughout the building lifespan. Using Revit, Abanda and Byers [36] developed a house model that was exported into Green Building Studio (GBS) for further calculations. The energyefficiency potential was explored by means of a parametric analysis for building orientation. GBS is particularly efficient to conduct extensive parametric analyses regarding building energy performance. Indeed, it has been successfully used to study the energy impacts of extensive combinations of envelope and internal configurations, e.g., Window-to-wall ratios, wall and roof construction materials, and HVAC, and of external conditions such as climatic ones, and orientation and building exposure levels (by means of building complexes) [37].
