sustainability Article BioZero—Designing Nature-Inspired Net-Zero Building Ljubomir Jankovic * and Silvio Carta   Citation: Jankovic, L.; Carta, S. BioZero—Designing Nature-Inspired Net-Zero Building. Sustainability 2021, 13, 7658. https://doi.org/10.3390/ su13147658 Academic Editor: Luis M. López-Ochoa Received: 3 June 2021 Accepted: 6 July 2021 Published: 8 July 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Zero Carbon Lab, School of Creative Arts & Centre for Future Societies Research, University of Hertfordshire, Hatfield AL10 9AB, UK; s.carta@herts.ac.uk * Correspondence: L.Jankovic@herts.ac.uk; Tel.: +44-7932-176-444 Abstract: This article introduces BioZero, a nature-inspired near-zero building proposed for Quay St, Brooklyn, New York. The building is designed for the maximum use of daylight and natural ventilation. This is the result of its shallow plan depth and the inner light wells/ventilation stacks, which also serve the inner circulation space. The light wells/ventilation stacks are created as a result of the organic shape of the internal partitions. The building is constructed from a steel frame and hemp-lime bio-composite material (hempcrete), which smooths out the fluctuations of internal air temperature and relative humidity. The south facing façade is fitted with the Cadmium Telluride (CdTe) photovoltaic array that covers 90% of the opaque surface area of the façade. The design was based on nature-inspired computation, with sustainability principles as guiding constraints. The main findings are that the building achieves −227 tonnes of negative embodied carbon due to sequestration of CO 2 in the hemp plant from which the material was harvested, and a net-zero operation. The main conclusions are that in the context of climate emergency, nature inspired design leads to energy efficient buildings with a high level of thermal comfort, which are buildable and sustainable. Keywords: nature-inspired; evolutionary computation; machine learning; net-zero; negative emis- sions; embodied emissions; hemp-lime; natural daylight; natural ventilation; renewable energy 1. Introduction BioZero, a nature-inspired net-zero building proposed for Quay St, Brooklyn, NY 11222, USA, is designed for the maximum use of daylight and natural ventilation. This is the result of its shallow plan depth and the inner light wells/ventilation stacks, which also serve the inner circulation space. The light wells/ventilation stacks are created as a result of the organic shape of the internal partitions. The building is constructed from a steel frame and 300 mm hemp-lime bio-composite (hempcrete) in the external envelope, which smooths out the fluctuations of internal air temperature and relative humidity, and achieving –227 tonnes of negative embodied carbon due to sequestration of CO 2 in the hemp plant from which the material was harvested. The south facing façade is fitted with the Cadmium Telluride photovoltaic array that covers 90% of the opaque surface area. The inspiration for BioZero design came together as result of the project team entering the 2020 ASHRAE LowDown Showdown Modelling Competition. This article introduces details of methods and the design process that resulted in the team’s competition entry. The competition brief required the building to be mixed-use multi-story, with 15 stories in total. The first two levels were for a lobby, retail spaces, fast food outlets, and a restaurant. Levels 3–14 were for residential spaces, with a mixture of studio, one-bedroom and two- bedroom apartments. The top floor was specified for a restaurant with indoor and outdoor space. The total floor area of the building was required to be 27,870 m 2 . The design was required to be sustainable and energy efficient, yielding carbon neutral or near carbon neutral building, and being resilient over a life span of 50 years under worst-case climate predictions. The ‘Bio’ designation of this design is inspired by principles of emergence in nature [1]. Sustainability 2021, 13, 7658. https://doi.org/10.3390/su13147658 https://www.mdpi.com/journal/sustainability