Biomimicry and Green Architecture: Nature-Inspired Innovations for Sustainable Buildings

Abstract

The building sector is a pivotal driver of global resource depletion and environmental deterioration, being responsible for 40% of raw material consumption, 16% of water usage, 25% of timber utilization, and 40% of total energy demand. It also accounts for 30% of worldwide greenhouse gas (GHG) emissions, predominantly CO₂. The operational phase of buildings is the most energy-intensive and emission-heavy stage, accounting for 85–95% of their total life-cycle energy consumption. This energy is primarily expended on heating, cooling, ventilation, and hot water systems, which are largely dependent on fossil fuels. Furthermore, embodied energy, the cumulative energy expended from the extraction of materials through construction, operation, and eventual demolition, plays a substantial role in a building’s overall environmental footprint. To address these pressing challenges, this study discusses sustainable innovations within green architecture and biomimicry. Our topic supports the 2030 vision Sustainable Development Goals (SDGs), both directly and indirectly (SDGs 7, 9, 11, 12, and 13). This study also explores cutting-edge applications, such as algae- and slime mold-inspired decentralized urban planning, which offer innovative pathways toward energy efficiency and sustainability. Considering the integration of renewable energy sources, passive design methodologies, and eco-friendly materials, this research emphasizes the transformative potential of biomimicry and green architecture in fostering a sustainable built environment, mitigating climate change, and cultivating a regenerative coexistence between human habitats and the natural world.

1. Introduction

The building sector heavily consumes resources, including 40% of raw materials, 16% of water, and 25% of global timber consumption. Additionally, the largest share of energy consumption is attributable to the built environment, consuming 40% of the total energy produced. Consequently, the building sector is accountable for 30% of total greenhouse gas emissions (GHG), mainly CO₂ [1,2]. Buildings are substantial energy consumers throughout their entire life cycle, comprising the design, construction, operation, and eventual demolition phases. A life-cycle analysis approach reveals that the operational stage is the dominant contributor, accounting for 85–95% of a building’s total energy use and CO₂ emissions. This operational energy demand arises from activities associated with occupancy, such as heating, cooling, ventilation, and hot water provision. It encompasses energy derived from various sources, including electricity, natural gas, and the combustion of fossil fuels, such as oil and coal. In addition to operational energy, the embodied energy within a building must also be taken into consideration. Embodied energy refers to the total energy consumed from a building’s creation to its demolition. This includes the direct energy used in construction and assembly processes, alongside the indirect energy associated with material and component manufacturing. The indirect energy component encompasses the entire energy chain, from raw material extraction and processing to final product manufacture. It also includes the transportation energy used throughout these stages and the embodied energy within the infrastructure of all systems employed during construction [3]. The CO₂ emitted throughout a building’s construction is classified into directly and indirectly emitted CO₂. Direct emission accounts for the ways in which energy is produced, such as burning natural gas, diesel, and so on, while indirect emission accounts for the use of energy in the building itself, such as lighting, cooling, and heating. The latter contributes 85% of the total emitted CO₂ [4].

The escalating global challenges stemming from anthropogenic climate change, the depletion of finite natural resources, and the unprecedented surge in urban populations have underscored the urgent need for a fundamental paradigm shift toward sustainable development. In this context, the United Nations’ Sustainable Development Goals (SDGs), a meticulously crafted and interconnected framework encompassing 17 distinct objectives, serve as a foundational blueprint for cultivating a more equitable, inclusive, and ecologically responsible future for humanity [5].

As energy is a top priority of the 2030 agenda of the Paris Agreement and an important factor in addressing climate change, our topic supports, both directly and indirectly, multiple SDGs, which are as follows:

SDG7: This articulates a pivotal global objective: to guarantee universal access to affordable, reliable, sustainable, and contemporary energy solutions by 2030. This overarching aim is systematically pursued through a multifaceted strategic framework that transcends mere electricity provision, fostering equitable energy accessibility and facilitating a comprehensive, sustainable energy transition worldwide [6,7].

SDG 9: This champions the construction of robust infrastructure, cultivating inclusive and sustainable industrialization, and invigorating innovation. This objective is indispensable for socio-economic advancement, necessitating considerable investment in reliable and sustainable infrastructure, encompassing vital regional networks.

SDG 11: This is dedicated to rendering cities and human settlements inclusive, safe, resilient, and sustainable by 2030, profoundly transforming urban environments to ensure equitable living conditions. Its core strategy prioritizes universal access to adequate, affordable housing and essential services. The goal also endeavors to establish safe, sustainable transportation networks and to foster inclusive urbanization through enhanced planning and governance. Furthermore, it encompasses safeguarding cultural heritage, substantially mitigating cities’ environmental impact, bolstering disaster resilience, and ensuring widespread access to verdant public spaces.

SDG 12: This advocates for a fundamental shift toward sustainable consumption and production patterns, recognizing that current global practices are unsustainable. Key targets include managing natural resources sustainably, halving global food waste, and ensuring environmentally sound management of all chemicals and waste.

SDG 13: This mandates urgent, decisive action to combat climate change and its pervasive impacts, recognizing its existential threat to the entirety of the 2030 agenda. Its focus encompasses both strengthening resilience and adaptive capacities to climate-related hazards across all nations [8,9]. Figure 1 shows all 17 SDGs.

Within this overarching framework, green architecture emerges as a crucial strategic intervention, offering a tangible and scalable pathway for ameliorating the substantial environmental footprint of the built environment. This sector is widely acknowledged as a significant contributor to global greenhouse gas emissions and the unsustainable consumption of finite natural resources [11,12], stemming from unsustainable energy consumption and production practices [13].

Green architecture encompasses a multifaceted and holistic array of design and construction methodologies, encompassing both passive and active strategies aimed at minimizing energy consumption through the optimization of building orientation, insulation, and ventilation systems; conserving finite natural resources through the strategic selection of sustainably sourced and low-impact building materials; promoting ecological integrity through habitat preservation, restoration, and the integration of green infrastructure; and enhancing occupant well-being through the creation of healthy, productive, and biophilic indoor environments [14,15,16]. By aligning architectural design principles with the overarching objectives of sustainable development, green architecture offers a tangible and scalable pathway toward the creation of built environments that are not only environmentally benign but also socially equitable and economically viable, thereby contributing to the realization of a resilient, regenerative, and sustainable future for generations to come. Green architecture consistently looks for new and inventive ways to cut down on carbon dioxide (CO₂) emissions from the energy buildings use, both when they are being built and throughout their lifespan. This often involves combining renewable energy sources, smart passive design techniques, and eco-friendly materials. One exciting area of inspiration is biomimicry, where we learn from nature, like how algae and slime molds handle energy and even urban planning, as shown in Figure 2. These nature-inspired ideas provide fresh avenues for making buildings much more energy-efficient and sustainable. By analyzing these concepts, we can better understand their potential to create urban environments that are both energy-efficient and environmentally friendly.

Biomimicry, inspired by nature’s strategies, drives innovation in architecture and the built environment, promoting sustainability and resilience. Through the emulation of natural forms and processes, it allows for the creation of energy-efficient, adaptive structures and materials, such as self-regulating building envelopes and bio-inspired composites. It also influences urban planning through biophilic designs and integrates nanotechnology for advanced materials. It advocates for regenerative practices, aiming to restore ecosystems and foster a harmonious relationship between human habitats and the natural world [17].

This review aims to address problems regarding our negative impact on the surrounding environment caused by our built environment and to introduce various sustainable solutions to mitigate this impact. It promotes intelligent solutions and new approaches to sustainability through biomimicry, considering algae and slime molds as models to develop robust tools for a greener and more sustainable future. It also explores green architecture as a crucial pathway to fostering environmental awareness and securing a sustainable future for both people and the built environment. As global challenges like climate change, global warming, and resource depletion intensify, there is an urgent need for sustainable solutions within our current architectural and construction practices.

2. Research Methodology

2.1. Research Questions

This review explores how nature-inspired innovations contribute to a more sustainable built environment. The investigation addresses two key research questions: First, what are the contemporary nature-inspired innovations currently applied in construction and urban development? Second, how do these innovations specifically support the achievement of the United Nations’ Sustainable Development Goals (SDGs), particularly those related to energy, infrastructure, urban communities, consumption, and climate action (SDGs 7, 9, 11, 12, and 13)?

2.2. Search Strategy

To find relevant peer-reviewed articles, an extensive search was conducted using Google Scholar, ScienceDirect, Refseek, and Semantic Scholar. Keywords like “green architecture,” “sustainability,” “SDGs,” “urban planning,” “nature-inspired architecture,” “nature-inspired photovoltaics,” “biomimicry,” “algae building technology,” and “slime mold” were strategically combined. Boolean operators (AND and OR) and truncation symbols (e.g., sustainab *) were used to ensure that the search was both broad and precise.

The primary focus was on publications from 2005 to 2024, as this period reflects recent progress and a heightened global emphasis on sustainability and SDGs. However, two foundational texts from 1975 and 1976 were also included to provide crucial historical context for nature-inspired design. To ensure the inclusion of only the most relevant and high-quality literature, references that directly discussed nature-inspired innovations, principles, or technologies within the built environment were included. Crucially, selected works also needed to address the sustainability benefits or SDG contributions of these innovations. The selection involved an initial compilation and deduplication of search results, followed by independent title and abstract screening by the author. Articles deemed potentially relevant then underwent a full-text review.

3. Literature Review

3.1. Sustainability as a Key Factor in the Construction Sector

Environmental sustainability denotes the enduring preservation of ecologically significant attributes within the natural world, encompassing the maintenance of essential systems and resources [16]. The concept of sustainability focuses on improving people’s quality of life such that they can live in an environment that is healthier, with better social, economic, and environmental circumstances. A sustainable project uses less energy and resources when it is planned, constructed, rebuilt, run, or repurposed.

Sustainable projects aim to accomplish multiple goals, including reduced CO₂ and GHG emissions, pollution avoidance, noise reduction, enhanced indoor air quality, resource and energy efficiency, and environmental harmony. Over the past several years, several efforts have been made to develop environmentally friendly and clean-energy alternatives, focusing on renewable energy and sustainability [17]. A wide array of recommendations has been established, including the use of sustainable energy sources, material and energy conservation, and natural resource conservation. The concept of conservation is to use the smallest number of resources necessary to accomplish one’s goals while preserving enough resources for future generations [3,18,19]. Therefore, using materials with a low carbon content will have a drastic effect on the life-cycle emissions of buildings, reducing them by about 30% [20].

By 2035, the carbon emissions attributable to buildings will reach 42.4 billion tons, which is an increase of 43% from what was emitted in 2007 [21]. The currently envisioned architecture and construction practices were initially formed by a sense of responsibility toward our environment. Global warming, climate change, and limited natural resource depletion have all paved the way toward seeking a better and greener future through the development of sustainable resources and energy-efficient buildings. Hence, green architecture is a discipline that will shape the future of sustainability and is capable of accomplishing both appealing designs and ecological harmony, with no need for compromise. Therefore, green architecture will play a pivotal role in addressing our environmental problems [22,23]. Urbanization has accelerated the depletion of our scarce natural resources, increased carbon emissions, and consumed a very large portion of the produced energy. However, the world now demands a sustainable future, making it necessary to use green sources of energy and compelling architects to design energy-efficient buildings [2].

The concept of green building is to create structures by implementing conscious resources and approaches. This technology promises to reduce water use by 20–30% and energy consumption by 40–50% compared to conventional buildings [24]. The estimation of the promising energy performance of such technologies will have a profound impact on the sustainable development of the building sector and will help to mitigate the significant negative impacts of the conventional building industry [25]. These technologies can also help to control the urban microclimate of both existing and new development projects [26].

3.2. Passive Building Design

Passive building design relies on using the natural elements surrounding a building to achieve energy efficiency. Solar and wind are the main elements to be exploited in passive design, avoiding the use of mechanical systems to regulate indoor temperature.

Passive building design involves strategically designing windows, vents, and other elements to help maintain a comfortable indoor environment using natural airflow and sunlight. Materials with high thermal mass are being considered because of their slow release of absorbed heat, which in turn reduces temperature variations indoors [2]. The aforementioned principles help to render buildings energy-efficient and conserve resources [3]. Thus, passive building design is not only an aesthetic concept or form, but also a process that includes suitable material choices to minimize energy consumption and to implement the strategies of passive design [27,28].

3.3. Renewable Energy Sources

Providing creative approaches aimed at lowering carbon dioxide (CO₂) emissions from the energy used during the construction and maintenance of buildings has gained global attention. Concerning this, the ability to develop the built environment sustainably is significantly influenced by the energy efficiency of green buildings [25].

The use of renewable energy sources throughout architectural designs represents a significant leap toward a built environment that is more environmentally responsible and sustainable [29]. Buildings have the ability to improve overall energy efficiency and actively mitigate carbon emissions by utilizing renewable resources [2]. The persistent reliance on fossil fuels for electricity generation remains a primary contributor to global warming. In recent years, significant efforts have been directed toward developing sustainable, eco-friendly, and clean energy alternatives [30].

The pressing need for sustainable architecture has positioned biomimicry, that is, the practice of drawing design inspiration from nature, as a key strategy for integrating renewable energy. Using this approach, we can significantly improve the efficiency of solar, wind, and geothermal technologies, reducing the substantial environmental impact of buildings. For instance, plant-inspired solar panels, designed to mimic leaf structures and arrangements, can improve energy production by 15–20% compared to traditional panels [19,31].

Solar photovoltaic (PV) panels are a renewable energy technology, and grid-connected PV system operations do not generate pollution or gas emissions. They work in accordance with the power needs and availability of solar energy reaching Earth’s crust [32,33].

Photovoltaic cells, also known as solar cells, are non-mechanical devices that can convert sunlight into electricity through the photovoltaic effect. In addition, some PV cells can convert artificial light into electricity. These cells work as semiconductor materials, providing and absorbing energy to generate electricity [34]. Contemporary urban landscapes increasingly feature photovoltaic (PV) modules integrated into various structures. Beyond their primary role in electricity generation, these devices serve diverse functions dictated by their placement and design. A discernible typology of PV-equipped installations has emerged, encompassing building-integrated photovoltaics, seamlessly incorporated into architectural elements like facades, roofs, overhangs, and even fences; overhead canopies and shading structures over open urban spaces such as pedestrian zones and parking areas, offering shelter while simultaneously generating power; and the growing trend of integrating PV technology into various pieces of urban furniture and public equipment, including solar-powered streetlights, “solar trees,” and smart benches, enhancing public amenities with sustainable energy solutions. Integrating PV modules into buildings not only augments their sustainable dimension but also adds an aesthetic dimension to the buildings [35,36,37,38]. Two examples will be discussed briefly, highlighting the integration of PV cells in architecture.

The advent of organic photovoltaics (OPVs) is fundamentally reshaping the application of renewable energy sources (RESs) within architectural design. This transformative potential was vividly illustrated by the German Pavilion’s Solar Trees, a hallmark feature showcasing OPV modules, as shown in Figure 3. These five imposing, twelve-meter-high structures not only serve as a striking visual motif but also underscore the pavilion’s broader emphasis on cutting-edge technologies and the prudent utilization of resources and space. OPVs distinguish themselves as flexible photovoltaic cells that harness organic compounds for both light absorption and charge transference. Their inherent pliability affords an expansive spectrum of architectural applications for such solar systems. Furthermore, the manufacturing methodologies for polymer OPV cells are comparatively straightforward, hinting at their potential for widespread, cost-effective deployment in the future. This particular photovoltaic technology is categorized as third-generation, succeeding silicon-based cells (Generation I) and thin-film cells (Generation II). Beyond their profound symbolic resonance, the Solar Trees command attention as a futuristic and dominant element within the German Pavilion, simultaneously providing visitors with welcome shade and serving as a highly efficient system for generating sustainable energy. Further examples of integrating PV cells into pavilions are mentioned in [39].

Projects such as Arup’s “Solar Leaf” demonstrate this by using branching patterns similar to leaves to maximize light absorption (Figure 4) [41,42]. Additionally, coatings inspired by the self-cleaning properties of lotus leaves can increase panel efficiency in dusty environments by up to 15% [31]. Furthermore, dynamic solar tracking systems, mimicking the movement of sunflowers, can increase energy yields by 20–40%, especially in low-light conditions [43,44].

Considering that buildings contribute roughly 40% of global CO₂ emissions from energy use [11], these nature-inspired solutions are crucial for achieving sustainable urban development. Architects and engineers are working toward creating buildings that align with ecological principles, fostering a more resilient future, and thus making effective contributions to more sustainable and environmental objectives [45].

3.4. Biomimicry in Green and Sustainable Construction

The discipline of emulating nature’s time-tested strategies to address complex human challenges has emerged as a groundbreaking paradigm in architecture and the built environment, catalyzing innovation, sustainability, and resilience [46]. Biomimetic design facilitates the development of structures and materials that are not only highly functional but also deeply integrated with their ecological context. This approach leverages the profound wisdom of nature’s 3.8 billion years of evolutionary refinement to devise solutions that optimize energy efficiency, material utilization, and environmental adaptability, thereby enhancing energy performance and occupant comfort [47].

Furthermore, bio-inspired materials, which replicate the hierarchical and multifunctional structures observed in natural composites, have been engineered to achieve exceptional mechanical strength, durability, and resource efficiency in construction applications [48], such as “biophilic cities,” which integrate natural systems to foster ecological harmony and enhance human well-being [49,50]. The synergy between nanotechnology and biomimetic principles has further propelled the field, enabling the development of advanced surfaces and materials with properties such as self-cleaning capabilities, hydrophobicity, and adaptive thermal regulation [51]. Moreover, biomimicry advocates for regenerative design practices, which aim to create built environments that actively restore and enhance ecosystem health rather than depleting natural resources [52,53]. Addressing multifaceted technical, environmental, and societal challenges, biomimicry in architecture and the built environment fosters a profound and symbiotic relationship between human habitats and the natural world, paving the way for a sustainable, resilient, and ecologically harmonious future [54].

Building materials that incorporate biomimicry utilize principles derived from natural systems to improve functionality, sustainability, and performance. For example, hydrophobic coatings inspired by the self-cleaning properties of lotus leaves, such as TiO₂⁻-based photocatalytic surfaces, have been developed to enhance durability and reduce maintenance requirements [55]. Similarly, adaptive building skins that emulate the responsive mechanisms of plant leaves or animal tissues, such as the Flectofin^® shading system, which is modeled after the deformation mechanics of bird-of-paradise flowers, optimize energy efficiency by regulating light, heat, and airflow [47,56].

Biomimetic materials also replicate structural designs found in nature, such as the hierarchical organization of bone or the lightweight yet robust geometry of honeycombs, to create construction materials with superior strength and resource efficiency. For instance, bio-inspired cement composites mimic the microstructures of nacre (mother-of-pearl) to achieve exceptional fracture resistance and mechanical strength [57].

Additionally, regenerative and eco-efficient materials—such as mycelium-based composites, which imitate fungal networks—are being developed to produce biodegradable and sustainable building components [58]. Nanotechnology significantly enhances its application in the built environment by enabling the precise replication of natural systems at the nanoscale, leading to innovative and sustainable solutions. For example, nanostructured surfaces inspired by the self-cleaning properties of lotus leaves have been developed using hydrophobic nanomaterials, such as silica nanoparticles, which reduce dirt accumulation and maintenance in building exteriors [59]. Similarly, the hierarchical structure of nacre has been mimicked using layered nanocomposites, resulting in cementitious materials with exceptional strength and toughness, offering sustainable alternatives for construction [60]. Nanotechnology also enables the creation of adaptive building materials, such as smart windows embedded with vanadium dioxide (VO₂) nanoparticles, which mimic the thermoregulatory properties of animal skin by modulating infra-red radiation in response to temperature changes [61]. Additionally, bio-inspired nanomaterials—such as cellulose nanocrystals, derived from plant cell walls—are being used to develop lightweight, high-strength composites for structural applications [62]. Furthermore, mycelium-based nanocomposites, which replicate fungal networks, are being explored for their biodegradability and potential use in temporary or regenerative structures [63]. By integrating nanotechnology with biomimetic principles, the built environment can achieve advanced functionality, sustainability, and resilience, while fostering a deeper connection with natural systems [64].

3.5. Integrating Bioenergy with Biomimicry in Architecture

Growing public awareness of the unsustainable nature of fossil fuels due to greenhouse gas emissions and resource depletion has sparked intense research efforts to create alternative energy sources. These projects concentrate on resources that are theoretically carbon-neutral and renewable, such as bioenergy made from algae [65]. Reducing carbon pollution could be accomplished by using clean technologies. These technologies can help reduce environmental degradation and greenhouse gas emissions, improving the efficiency of sustainable living [66]. Integrating bioenergy with biomimicry in architecture offers a promising path to sustainable buildings. Bioenergy provides renewable fuel while optimizing the use of resources by emulating natural systems. Algae facades exemplify this synergy, using photosynthesis for bioenergy, insulation, and air purification. They represent a novel approach to architecture, blending bioenergy and biomimicry to create sustainable buildings [67,68].

3.6. Algae as a Sustainable Building Technology in Green Architecture

Utilizing algae falls within the general scope of biomimicry [1], providing inspiration to build professionals and serving as a useful resource for engineers and architects. Through the utilization of computational simulations and natural processes, biological systems provide innovative solutions to contemporary problems. These solutions, which are characterized by their renewability, flexibility, adaptability, and variety, have great potential to improve the built environment [69]. With so many benefits to offer, algae have great potential as a diverse and sustainable source of green energy. To begin with, they are a key tool in the fight against climate change due to the ability they possess to effectively absorb and reduce CO₂ and other greenhouse gases while releasing oxygen into the atmosphere. Second, algae show promise for bioengineering and quick growth, distinguishing them from traditional crops and providing a flexible and consistent biomass supply. Moreover, they support a circular economy by using nutrients found in wastewater, supporting waste management [70,71]. Additionally, algae are more tolerant of a broad range of habitats than land-dependent crops, which reduces competition for agricultural land. Ultimately, adding algal facades to buildings improves air quality and creates a greener environment by encouraging carbon sequestration and oxygen generation while improving urban aesthetics [1]. These facades use microalgae photosynthesis to produce biofuel, provide insulation, purify air, and enhance building aesthetics. By growing algae in transparent panels within building walls, they create a dynamic link between buildings and natural processes. These facades use algae to convert sunlight and CO₂ into biomass, which can be turned into biofuels for on-site energy. They also improve air quality by absorbing CO₂ and releasing oxygen, reducing a building’s carbon footprint. The algae-filled panels’ insulation properties reduce the need for traditional heating and cooling, thus saving energy [72,73]. The BIQ House in Hamburg, Germany, is a key example, demonstrating how algae facades can generate heat and hot water (Figure 5) [74,75,76]. Research has focused on improving these systems, exploring better photobioreactor designs, light optimization, and integrated controls to maximize algae growth [75]. Studies have also shown that integrating these facades with ventilation systems can improve indoor air quality and reduce energy use [77,78]. Ongoing research aims to make algae facades more scalable, cost-effective, and widely used in architecture. These efforts seek to fully utilize algae facades as a sustainable and multifunctional building technology.

Algae facades represent a novel architectural approach, blending bioenergy and biomimicry to create sustainable buildings. This application is known as “algae-building technology” (ABT). Cutting-edge technologies are being designed to lessen our reliance on fossil fuels, lower the carbon footprint of the building industry, and turn buildings from energy consumers into energy producers. Photobioreactors (PBRs) are a promising use of this technology, as they can produce biomass and heat energy concurrently [65,71,79,80,81].

3.7. Slime Mold-Based Model for Integrating Renewable Energy Sources and Eco-Friendly Materials

The slime mold Physarum polycephalum is a plasmodium that consists of large amoeba-like cells with pseudopodia (tube-like structures) that are arranged in a dendritic network. As it moves across an average agar gel, its shape changes, and it releases pseudopodia to link two food sources when they are placed at different locations [82]. Perfected by endless cycles of evolutionary selection, this slime mold is a single-celled organism that has proven to have a dependable and economical network construction capacity based on its feeding capabilities. In a test to determine the shortest path between two points in a labyrinth, this small organism easily solved the problem without needing to go back [83]. Additionally, slime molds have demonstrated memory retention and learning capabilities through habituation, which is thought to be the most fundamental kind of learning [84,85]. Plasmodium, the vegetative form of a slime mold, comprises numerous small oscillators. The frequency of these oscillators’ changes is based on their interacting environment [86]. In the presence of an attractant or the binding of specific molecules, oscillators near this attractant raise their frequency, leading to the flow of cytoplasm toward the proximal end of the food (Figure 6). On the other hand, in the presence of repellents, such as light, the oscillation frequency diminishes. Such a mechanism rules the organism’s locomotion in an environment [87,88]. An extracellular translucent slime is excreted as the plasmodium moves, which it deliberately avoids when in search of food. Consequently, this simple yet intelligent organism can create a spatial memory, recognizing its surrounding environment when sensing the extracellular slime [89,90].

The maze problem, a classic challenge in both biology and computational science, involves finding the most efficient path between two points within a complex network of pathways. Slime molds, particularly Physarum polycephalum, have demonstrated extraordinary proficiency in solving such problems despite their simple, brainless structure. When placed in a maze with food sources at the start and end points, the slime mold extends its network of protoplasmic tubes, exploring multiple routes simultaneously. Over time, it reinforces the most efficient path, which is typically the shortest or least resistant route, while retracting from dead ends and longer pathways [82]. This behavior is driven by the organism’s ability to sense and respond to chemical gradients, allowing it to dynamically adapt its growth patterns to optimize nutrient acquisition. The study of slime molds and the maze problem continues to provide valuable insights into decentralized intelligence, adaptive systems, and the intersection of biology and technology, and the study of slim molds’ growth stages with the active plasmodial Physarum polycephalum, which provides needed nutrient sources, will offer smart and innovative solutions to solve real-world problems, the models mimicking this smart organism’s ability to find minimal paths and adapt to changing conditions, whereby it can simultaneously refine efficient links destroy and reduce redundancies. Slime molds, simple intelligent organisms, can create spatial memories and recognize the surrounding environment when they sense extracellular slime. This ability of slime molds to address intricate network challenges, such as optimizing transportation pathways, exemplifies the potential of bio-inspired algorithms in urban planning and infrastructure development [91,92,93,94,95,96].

Recent research has expanded on these findings, revealing that slime molds can solve more complex maze configurations, including three-dimensional mazes and those with multiple food sources. These studies have highlighted the organism’s ability to balance exploration and exploitation, a key feature of efficient problem-solving. Additionally, slime molds have been shown to “remember” past pathways by leaving behind extracellular slime trails, which act as a form of spatial memory, helping them to avoid revisiting unproductive routes. This memory-like behavior enhances their efficiency in navigating intricate environments [90] (Figure 7).

The implications of slime mold maze-solving extend beyond biology, inspiring bio-inspired algorithms for optimization problems in fields such as robotics, urban planning, and network design. For instance, models inspired by slime molds can help to design efficient transport networks that mimic human-engineered systems, such as the Tokyo rail system, by optimizing connectivity and minimizing costs [91]. Similarly, exploring the use of slime molds in computing showed how their adaptive behaviors can be harnessed to create logical gates and solve computational problems. These models mimic the organism’s ability to find minimal paths and adapt to changing conditions, offering robust solutions to real-world problems. Overall, the study of slime molds and the maze problem continues to provide valuable insights into decentralized intelligence, adaptive systems, and the intersection of biology and technology [92,93] (Figure 8).

Furthermore, the idea of utilizing such a mechanism to predict the layout of urban plans, roads, and railways has been put forward. As slime molds can find the shortest path between two food sources, this concept was implemented for the simulated design of the Tokyo railway system, validating the possibility of using such a mechanism in further decentralized domains in urban design. To imitate the Tokyo railway, thirty-six food sources were used to mimic proximal geographical locations to Tokyo, with the slime mold starting in Tokyo. Light was also used as a repellent to further imitate geographical features of the land, such as lakes, oceans, and low-altitude regions. The growth of the organism was then observed. The network that this organism established was incredibly similar to the on-site railway [87] (Figure 9).

The organism’s ability to find minimal paths and adapt to changing conditions, whereby this smart organism can simultaneously refine efficient links and destroy and reduce redundancies, offers robust solutions to real-world problems. Similar urban planning challenges have also been given to the biological computer, Physarum. Iberian road networks have been redesigned using slime molds, creating transport networks that are distinct from current road portions while providing equivalent transport capacity. Comparably, Physarum adjusted the route of the M6 motorway through Newcastle. It has also raised concerns about the Mexican highway system’s redundancy. This biological computer presents a novel computational paradigm for unique data processing, problem-solving, and memory storage. It can process new information, make reasonable decisions, and learn despite the absence of a neural circuit [94]. Through further in-depth investigations, it is expected that this organism’s way of living can be further exploited in many applications [94,95,96,97].

Through implementing an appropriate algorithm that mimics the mechanism of slime mold, renewable energy sources and eco-friendly materials can be effectively integrated. With appropriate parameters, an HVAC system’s layout can be predicted for any building. This will aid in accomplishing more goals toward a more sustainable built environment and energy-efficient buildings, contributing to a sustainable approach and promoting the healthy growth of cities [98] (Figure 10).

4. Conclusions

The construction sector currently faces a critical challenge, acting as a significant contributor to resource depletion and greenhouse gas emissions. It consumes a substantial portion of global raw materials, water, and timber, and accounts for 40% of total energy use. This substantial environmental impact, largely driven by the energy-intensive operational phase of buildings, necessitates an urgent shift towards global sustainability.

This transformation is crucial given pressing global issues like climate change, the dwindling supply of natural resources, and rapid urbanization. In response, the United Nations’ Sustainable Development Goals (SDGs) provide a vital framework, guiding humanity toward a more equitable, inclusive, and environmentally responsible future. For SDG 7 (Affordable and Clean Energy), PV cells directly supply clean, renewable electricity, diminishing reliance on fossil fuels and broadening access to sustainable power. ABT produces bioenergy, like biofuel and heat, through photosynthesis, essentially transforming buildings into localized energy hubs. While not a direct energy source, slime mold-inspired biomimicry can optimize urban energy distribution networks, indirectly boosting energy efficiency. In support of SDG 9 (Industry, Innovation, and Infrastructure), PV cells drive innovation in renewable energy infrastructure and manufacturing, fostering sustainable industrial growth. ABT represents a pioneering building solution that integrates biological processes into construction, promoting novel and sustainable methodologies. Slime mold-inspired algorithms can optimize critical infrastructure networks, such as transportation and utilities, leading to more efficient and resilient urban planning. Regarding SDG 11 (Sustainable Cities and Communities), PV cells enable cities to become more sustainable by providing clean, decentralized power; curbing urban pollution; and enhancing infrastructure resilience. ABT improves urban environments by enhancing building aesthetics, offering insulation, and purifying air through CO₂ absorption, making cities healthier and more livable. The network optimization capabilities of slime mold can inform the design of more efficient and adaptable urban layouts, fostering truly sustainable and resilient communities. For SDG 12 (Responsible Consumption and Production), PV cells champion responsible energy consumption by offering a renewable alternative to fossil fuels and encouraging sustainable manufacturing practices. ABT harnesses natural processes for energy generation and provides sustainable alternatives for building materials. Furthermore, algae’s capacity to sequester CO₂ and remediate wastewater actively promotes circular economy principles. Slime mold’s influence on optimized resource allocation in urban development directly aligns with responsible consumption patterns. Finally, concerning SDG 13 (Climate Action), PV cells significantly reduce greenhouse gas emissions by displacing fossil fuels, directly contributing to climate change mitigation. ABT plays an active role in climate action by absorbing atmospheric CO₂ during photosynthesis, converting it into biomass, and supplying carbon-neutral energy sources for buildings. Though indirect, the inherent efficiency of slime molds in network formation can lead to reduced overall energy consumption and optimized resource use in urban systems, thereby lessening the carbon footprint and bolstering climate change mitigation efforts.

Green architecture offers a fundamental and scalable approach to reducing the environmental footprint of buildings. This discipline champions holistic design and construction methods that minimize energy consumption through optimized design, conserve natural resources through sustainable material choices, promote ecological integrity, and enhance occupant well-being. By integrating renewable energy sources, smart passive design, and eco-friendly materials, green architecture actively works to cut carbon emissions throughout a building’s entire lifespan.

In essence, the urgent need for sustainable solutions in architecture and construction is clear. By embracing green architecture, leveraging the transformative power of biomimicry, and aligning with the comprehensive vision of the United Nations’ Sustainable Development Goals, the built environment can transition towards an environmentally benign, socially equitable, and economically viable future. This integrated approach is vital for effectively addressing current global challenges and fostering sustainable urban development for generations to come.