**1. Introduction**

Buildings are a central part of the transition to a low-carbon society, with less environmental impact and energy efficiency, as they are responsible for consuming 32% of all energy generated in the world. This is equivalent to 19% of greenhouse gas emissions [1], in addition to consuming 50% of all raw material extracted by human action [2]. Initiatives such as the Sustainable Development Goals (SDGs) of the United Nations (UN) [3], the New Urban Agenda [4], and the Paris Agreement [5] point to the need for the reduction of energy consumption in buildings, generation of clean energy and more sustainable cities and communities to mitigate climate change and environmental crisis.

Buildings with zero energy balance, also known as the term Zero-Energy Buildings (ZEB), have an equivalent demand and generation of renewable energy within a year [6]. However, the equivalence between consumption and generation is not enough, because it is essential to achieve a demand reduction. For this, conservation and energy efficiency strategies are needed from the preliminary design [7], since they also provide thermal and lighting comfort, in addition to minimizing the environmental impact of the building in its operating phase. This includes integration with passive strategies, particularly in terms of natural lighting and ventilation, and high-performance enclosures. According to [8], new buildings have the potential to reduce energy demand by 50% if compared to the traditional ones, only by adopting commercially available energy conservation and efficiency strategies.

Thereby, the idea of NZEB emerged in the 1990s and afterward became part of energy policies in several countries. In Europe, the EU Directive on Energy Performance of Buildings [9] set goals to turn all buildings nearly zero-energy by 2020. The US Department of Energy's Building Technologies Program established similar objectives: achieving zero energy homes by 2020 and zero-energy commercial buildings by 2025 [10]. In addition, this building category is aligned with the 7 and the 11 UN Goals of Sustainable Development. According to O´Brien et al. [7], the NZEBs are characterized by a rigorous design and operation of the building as an integrated energy system, with a good indoor environment suited to its role. Some key points are mentioned, such as: an integrated approach to energy efficiency, passive and active design and building operation; optimization of solar collection, requiring building design and roofs used for conversion to electrical energy, useful heat, and natural lighting. **Table 1** shows the difference in project design and operation between conventional buildings and NZEB buildings.

In Brazil, there is still no regulation regarding NZEBs, but specific actions have been taken to leverage the improvement of energy efficiency in buildings, through regulations and standards [11], building performance [12], and distributed energy generation [13]. However, concrete actions for the construction and monitoring of NZEB buildings are recommended to enable the dissemination of the concept. In this context, the National Program for Energy Efficiency in Buildings (Procel Edifica) carried out a Public Call in 2019 to support the construction of up to 4 (four) NZEB's in strategic locations throughout the country [14]. The objectives of the call included: to foster knowledge, research, and development of NZEB project designs; to create a demonstration effect of NZEB buildings, enabling large-scale adoption, and, finally, to verify the technical and financial feasibility of the construction and operation of NZEB buildings. The Public Call was launched on December 2nd, 2019, and the deadline was set to February 20th, 2020. The call requested the submission of the Basic Project Design of the NZEB new construction or to undergo retrofit, bringing

*An Integrated Design Process in Practice: A Nearly Zero Energy Building at the University… DOI: http://dx.doi.org/10.5772/intechopen.102443*


#### **Table 1.**

*Design and operation of NZEB buildings versus conventional buildings.*

together "the elements that define the building, aiming at the accuracy of its basic characteristics and its desired performance in the work, with the estimated cost and execution time" [14].

The University of Brasília (UnB) has been investing in strengthening sustainability actions on its campuses; according to Taucher and Brandli [15] (2006) "the socio-environmental dimension, in this context, stands as a principle for institutional development". Thus, the construction of a zero-energy balance building and possibly replicable typology proves to be an important step towards the dissemination and consolidation of sustainable practices at the University, with positive consequences and impacts even for the city. Therefore, to advance on sustainability purposes, UnB's multidisciplinary team developed a project design for a laboratory and coworking space, called LabZERO|UnB, which was one of the 4 buildings included in the socalled Procel Edifica Public Call (3rd place overall).

This study presents in detail the design process experience of this NZEB building initially, all design phases, results, barriers, and potential are addressed. Afterward, the final design and the analysis of environmental and energy performance are presented, and the challenges to the implementation of this type of practice, and the relevance of initiatives to promote the dissemination of zero-energy balance buildings, are discussed.
