UNIVERSITY SCHOOL OF ARCHITECTURE AND PLANNING Guru Gobind Singh Indraprastha University Dwarka Campus, Delhi
RESEARCH PAPER, 2015-16
BIOMIMETIC RESPONSE TO CLIMATE
SHALINI SINGH ROLL No. – 07690701612 Fourth Year, Section B
GUIDE: Ar. Priyajit Pandit
Biomimetic Response to Climate
UNIVERSITY SCHOOL OF ARCHITECTURAL AND PLANNING Guru Gobind Singh Indraprastha University Dwarka Campus, Delhi
Approval
Research paper title: Biomimetic Response to Climate The following study is here by approved as a creditable work on the approved subject, carried out and presented in a manner sufficiently satisfactory to warrant its acceptance as a pre-requisite to the degree for which it has been submitted. It is to be understood that by this approval, the undersigned does not necessarily endorse or approve any statement made, opinion expressed or conclusion drawn therein, but approves the study for the purpose of which it is submitted and which satisfies the requirements laid down by the Research Paper Committee.
Date:
Submitted by: SHALINI SINGH
Guide: Ar. Priyajit Pandit
Roll No.: 07690701612
Ar. Siddhart Khitoliya (Research Paper Co-ordinator)
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Biomimetic Response to Climate
Acknowledgement
I earnestly acknowledge the opportunity provided by University School of Architecture and Planning to realize my dissertation programme under the guidance of Ar. Priyajit Pandit. I express my sincere gratitude to my dissertation guide Ar. Priyajit Pandit for her able guidance, continuous support and cooperation throughout my project, without which the present work would not have been possible. I would like to thank our coordinator Ar. Siddharth Khitoliya for his constant support and help in the completion of my project. Also, I am thankful to my college library for helping me find out the material for my project. I would like to thank my parents as well for the continuous guidance and invaluable encouragement. Finally, I thank all those people whose silent presence gave me the right insights to complete the project.
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Table of Contents Approval………………………………………………………………………………………2 Acknowledgement…………………………………………………………………………….3 Table of contents………………………………………………………………………….......4 Table of figures……………………………………………………………………………….6 1. Introduction………………………………………………………………………………9 1.1. Objective……………………………………………………………………………….10 1.2. Research Questions…………………………………………………………………….10 1.3. Hypothesis………………………………………………………………………………10 1.4. Methodology……………………………………………………………………………11 1.5. Scopes and Limitations………………………………………………………………....11 2. About……………………………………………………………………………………..12 2.1. What Is Biomimicry?………………………………………………………………..........12 2.2. Climate Concern………………………………………………………………...............13 2.3. Nature’s Response………………………………………………………………............14 i. Snail’s Shell……………………………………………………………….........................14 ii.
Termite Mound………………………………………………………………................15
iii. Cactus………………………………………………………………..............................15 3. Theory……………………………………………………………………………………16 3.1. Snail’s Shell Remains Cool……………………………………………………………...16 3.2. Termite Mound Is Well Ventilated……………………………………………………...18 3.3. Cactus’ Ribbed and Spined Structure Keeps It Shaded…………………………………20 4. Applications in Architecture……………………………………………………………22 4.1. Shell……………………………………………………………….................................22 4
Biomimetic Response to Climate
4.2. Mound………………………………………………………………..............................26 4.3. Cactus……………………………………………………………….............................31 5. Conclusion……………………………………………………………………………….33 5.1. Snail Shells Can Be Replicated In Hot Climate………………………………………...33 5.2. Termite Mound Design Can Help Save Energy………………………………………..34 5.3. Cactus Can Inspire the Structure of a Building………………………………………..35 5.4. A Combination of All Three……………………………………………………………36 Bibliography…………………………………………………………………………………37
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Table of Figures
Figure 1: Desert Snail, Sphincterochila prophetarum by Jonathan http://www.asknature.org/strategy/1683ae77eb0b8030d6c81e7098ddcd3c Figure 2: Macrotermes michaelseni mound by Mercedes http://www.asknature.org/strategy/8a16bdffd27387cd2a3a995525ea08b3 Figure 3: Peruvian torch cactus by Paul Benford http://www.asknature.org/strategy/0aaa42953466bee0b1f530ac73a28312 Figure 4: Section of snail’s shell by Stinj Ghesquiere Figure 5: Desert snail biological principle by Gretchen http://www.asknature.org/strategy/1683ae77eb0b8030d6c81e7098ddcd3c Figure 6: Holes in termite mound, Shutterstock http://www.asknature.org/strategy/8a16bdffd27387cd2a3a995525ea08b3 Figure 7: Sketches of Termite Mound by Henife http://www.asknature.org/strategy/8a16bdffd27387cd2a3a995525ea08b3 Figure 8: Infrared Image of Cactus by Coen http://www.asknature.org/strategy/0aaa42953466bee0b1f530ac73a28312 Figure 9: Barrel Cactus, Erin Leitch http://www.asknature.org/strategy/0aaa42953466bee0b1f530ac73a28312 Figure 10: Mechanism for cooling in torch cactus. Artist: Emily Harrington. http://www.asknature.org/strategy/0aaa42953466bee0b1f530ac73a28312 Figure 11: Form inspired architecture from the barrel cactus. Image by Rui Felix https://bouncingideas.wordpress.com/2011/12/14/learning-from-a-barrel-cactus/#more-539 Figure 12: Shading analysis Thesis on bio-mimicry of snail by shaikh nawaz altaf Figure 13: Analysis grid showing average daily incident radiation Analysis grid showing thermal comfort Thesis on bio-mimicry of snail by shaikh nawaz altaf Figure 14: Physical prototypes made using the paper ribbons Thesis on bio-mimicry of snail by shaikh nawaz altaf 6
Biomimetic Response to Climate
Figure 15: Construction of this form by the use of dry joints Thesis on bio-mimicry of snail by shaikh nawaz altaf Figure 16: 3d model Thesis on bio-mimicry of snail by shaikh nawaz altaf Figure 17: ventilation through the architectural form Thesis on bio-mimicry of snail by shaikh nawaz altaf Figure 18: David Brazier. Illustration by Daniel Gallant/Foundry Zero. Adapted from artwork courtesy of Mick Pearce. Figure 19: Illustration by Daniel Gallant/Foundry Zero. Adapted from artwork courtesy of Mick Pearce. Figure 20: CH2 Building http://www.walkingmelbourne.com/forum/viewtopic.php?f=6&t=2704 Figure 21 to 27: http://www.archdaily.com/395131/ch2-melbourne-city-council-house-2designinc/51cc725fb3fc4be56b000081-ch2-melbourne-city-council-house-2-designinc-section-c-designinc Figure 28: Minister of Municipal Affairs and Agriculture office in Qatar http://inhabitat.com Figure 29: Sea Shell House by Radu26 http://www.deviantart.com/art/Sea-Shell-House-394414711 Figure 30: Image by Ruzelli http://nautil.us/issue/8/home/the-termite-and-the-architect Figure 31: Cactus house by inkydays https://inkydays.wordpress.com/2013/11/17/cactus-house/ Figure 32: Rhagada barrowensis by WA Museum Figure 33: Termite Mound By Bill Bachman Figure 34: Cactus http://reviveyourbath.blogspot.in/2013/05/feeling-like-cactus.html Figure 35: Suggested form
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“I think the biggest innovations of the 21st century will be at the intersection of biology and technology. A new era is beginning.” -Steve Jobs
“When we look at what is truly sustainable, the only real model that has worked over long periods of time is the natural world.” -Janine Benyus
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Biomimetic Response to Climate
1. Introduction It all started with my love for nature. I always used to wonder how marvelously the nature has been designed. From all the colours to the physical forms like rivers, mountains, birds, flowers, rainbow, snowfall etc., everything in nature has always fascinated me and this led to the questions in my mind like ―how has it all been done?‖ The organisms other than the humans have been living on the earth since so many years without doing any harm to the nature. If other organisms can do it then why can’t we? It took so many years for the earth to be made and only a few years of human era to cause harm to the environment. We humans have blindly used the resources for our selfishness and now we are facing the problems like Global Warming. The field of architecture is a major constituent of the human made world. The massive buildings if all taken together contribute a large amount in the global energy consumption. Maximum of which is happening by our greed to become more and more comfortable day by day. Why can’t the nature and our buildings go hand in hand and the man-made structures become the friends of the planet rather than the enemies? I came to know about one way to do this and that was BIOMIMICRY (Mimicking nature to achieve a certain goal). Climate is one of the important factors to decide upon the total energy consumption of any building. If we live in comfortable climates, we tend to use less heating or cooling equipment and therefore, we consume less energy. Equipment like air-conditioning systems are leading to harmful effects to the environment and hence to the nature. My sensitiveness towards the nature pushed me for this research on the ways in which we can replicate the natural forms and functions in our buildings in order to make them respond to the climate passively in a similar way as other organisms do. Other organisms also live on the same planet and consume almost negligible energy. Why can’t we learn from them? Their passive heating and cooling techniques can be very useful for architects. If we learn to build like nature, there will be so much left for our future generations to see. To set up the scope of study for this research paper, some organisms’ features that respond to the hot climate (focus is on reducing the air conditioning load) in the architectural way were listed down namely: 1. Snail’s Shell 2. Termite Mound 3. Cactus’ Form
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Every organism has its own importance and uses its features to tackle the heat in its own way and as per requirements. But after some more reading and understanding of the concepts of biomimicry and relating it to architecture, the form and the related cooling mechanism of the three was chosen to be studied and explored more. This research paper ―Biomimetic Response to Climate‖ tries to study these natural responses and get on to a suitable conclusion.
1.1. Objective
To study the passive cooling techniques of some native organisms responding to hot climate in architectural way.
To study how these forms have already been used in architecture.
To discover whether all the forms can be incorporated in one building for better performance.
1.2. Research Questions
Can Biomimicry be useful for responding to the hot climatic conditions?
What features provide comfort to the organisms?
Can extremely hot and arid Deserts also be a place to live?
Can these features be implemented in Architecture?
1.3. Hypothesis The hypothesis so formed by this study:
Snail shell’s form protects it from heat.
Termite Mound remains well ventilated.
Cactus’ Form keeps it shaded.
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1.4. Methodology The approach adopted here is the identification of a particular problem and then finding its solution in the nature. This study seeks the climatic response of native organisms for which only hot climate will be taken into consideration and three native organisms’ features – Snail’s Shell, Termite’s Mound and Cactus’ Form will be studied. The study will be carried out using both primary and secondary methods of research. Primary method will majorly include studying the shadow and ventilation patterns by creating models similar to the forms. The secondary data collection will be done by reading books and collecting information and imagery from the internet. This will include:
Reading and understanding the concept of biomimicry written by famous theorist Jenine Benyus.
Learning about the climatic concerns in architecture from the work of researcher Pedersen Zari.
Reading the studies already done on the organisms’ heat tackling techniques by scientists/biologists.
Works of researchers and case studies of architects who have done such projects.
A few organisations and websites have been created to make people learn about the nature deeply which can be very helpful in this field such as The Biomimicry Institute, Biomimicry 3.8 and Ask Nature.
1.5. Scopes and Limitations This study sets up the scope for understanding biomimicry in terms of climatic responses and its implementation in the buildings and the scope of harsh climatic regions like deserts to become livable places. The research can be taken further and used to produce excellent climate responsive buildings with passive cooling techniques, very eco-friendly in nature. The study is limited to looking at only the native organisms of hot climate, mostly deserts around the world for which only three organisms have been considered for their form-based design.
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2. About 2.1. What is Biomimicry? The term biomimicry appeared in 1982. Biomimicry was popularized by scientist and author Janine Benyus in 1997 in her book Biomimicry: Innovation Inspired by Nature. The book defines Biomimicry as a "new science that studies nature's models and then imitates or takes inspiration from these designs and processes to solve human problems". Benyus suggests looking to Nature as a "Model, Measure, and Mentor" and emphasizes sustainability as an objective of biomimicry. ―Biomimicry is an innovation method that seeks sustainable solutions by emulating nature’s time-tested patterns and strategies, e.g., a solar cell inspired by a leaf. The goal is to create products, processes, and policies—new ways of living—that are well-adapted to life on earth over the long haul.‖ – Biomimicry Institute. According to The Architecture Annual 2007-2008. Delft University of Technology: Biomimicry is a multidisciplinary field which refers to the design based on principles, processes and methods extracted and abstracted from the nature. This approach results in the designs that are similar to the functional concept of an organism or an ecosystem. The biomimicry field is rapidly growing as both an academic and an applied discipline, and this is noticeable in the dedicated journals and the growing research through the years. The growing interests in biomimicry suggest that the professional are becoming more aware that nature has much to offer in order to improve the way our systems function. Pedersen investigates the possibilities to mitigate the effect of climatic change on the built environment with the help of biomimicry. She demonstrates the various ideas to be applied in the design for short, medium and long term response to climatic change. The integration of ideas of the living world into architecture could lead to an essential step towards a more sustainable built environment that is able to adapt to climate change. Also, addressing the negative environmental impacts by using biomimicry into design could lead to a more functional, livable, loved and beautiful habitats for ourselves. Biomimicry in architecture could lead to buildings that function as systems and organisms or as their integration. Biomimicry, where flora, fauna or entire ecosystems are emulated as a basis for design, is a growing area of research in the fields of architecture and engineering. This is due to both the fact that it is an inspirational source of possible new innovation and because of the potential it offers as a way to create a more sustainable and even regenerative built environment. A framework for understanding the various forms of biomimicry has been developed, and is used to discuss the distinct advantages and disadvantages inherent in each as a design methodology. Biomimicry exists at three different levels: 1) Organism level 2) Behaviour level 3) Ecosystem level
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Approaches to biomimicry as a design process typically fall into two categories: Defining a human need or design problem and looking to the ways other organisms or ecosystems solve this, termed here design looking to biology, or identifying a particular characteristic, behaviour or function in an organism or ecosystem and translating that into human designs, referred to as biology influencing design (Biomimicry Guild, 2007). Within the two approaches discussed, three levels of biomimicry that may be applied to a design problem are typically given as form, process and ecosystem (Biomimicry Guild, 2007) In studying an organism or ecosystem, form and process are aspects of an organism or ecosystem that could be mimicked. This research paper tends to adopt the first approach in which the solutions to tackle the heat are being searched in the nature at the organism level.
2.2. Climate Concern Climate change will affect many aspects of life and has well documented social, economic and environmental impacts (Chapman et al., 2006; Stern, 2006). Public awareness of this and with it Government directives to address climate change issues, have significantly increased. Coupled with this is the growing realisation that the global built environment contributes significantly to the causes of climate change through construction and demolition practices, but most significantly through operational and embodied energy (Levine et al., 2007). The built environment is increasing held accountable for global environmental and social problems with vast proportions of waste, material and energy use and greenhouse gas emissions attributed to the habitats humans have created for themselves (Mazria, 2003, Doughty and Hammond, 2004). The global built environment contributes significantly to the causes of climate change through construction and demolition practices, but most significantly through operational and embodied energy (Levine et al., 2007). Not only is the built environment responsible for approximately a third of global greenhouse gas (GHG) emissions, leading to climate change (de Ia Rue du Can & Price, 2008), it will also have to adapt to climate change impacts, as the main site of human economic, social and cultural life (Hunt, 2004). In light of this, architecture and design education will also have to change so that graduates understand both how to mitigate the causes of climate change, as well as how to devise built environments that can adapt to the impacts. India and other nations in South Asia and Southeast Asia are on track to record the world’s biggest increases in demand for air conditioning. Mohammad Arif Kamal, an assistant architecture professor at Aligarh Muslim University, explains that air conditioning has become de rigueur in India. ―Air conditioning has become a social and status symbol,‖ he says. ―People are discarding their old, traditional homes made of bricks, mud, adobe, timber, bamboo, etc., in exchange for boxes made of concrete and glass in pursuit of modernization, which consumes a lot of operational energy.‖ In addition to placing strains on nations’ power grids, air conditioners pose threats to the environment and environmental health, primarily as contributors to global warming. ―The amount of electricity that’s used for air conditioning is a huge part of an energy load for most countries, and it’s going up,‖ says Durwood Zaelke,
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president of the nonprofit Institute for Governance and Sustainable Development. ―You’re putting out more climate pollutants as you’re burning more coal or gas to run the air conditioners, and you’re also putting out the greenhouse gases that serve as the refrigerants in the equipment.‖ The buildings in the hot climate need to be passively cooled in order to lessen its energy consumption. To reduce such loads on the environment, it is becoming increasingly clear that a shift must be made in how the built environment is created and maintained. Mimicking life, including the complex interactions between living organisms that make up ecosystems is both a readily available example for humans to learn from and an exciting prospect for future human habitats that may be able to be entwined with the habitats of other species in a mutually beneficial way.
2.3. Nature’s Response Around the globe, deserts and other harsh and hot climates seem unbearable to humans who are used to air conditioning, cars and other facilities of modern life. Evolution is smart, though, and organisms of desert and tropical climates show all sorts of adaptations that help them survive in the heat and with scarce water. Most creatures have a variety of tricks to survive this sort of brutal environment. Some organisms respond to the hot climatic condition in the most architectural ways rather than biological ones. A few of them are snail, termite mound and cactus which can survive in extreme heat even at a place where we humans are not living due to hostile climate. These organisms can inspire us to make built environments which are naturally cooled down without harming the planet.
i. Snail’s shell The shell of some desert snails helps them survive extreme heat using light reflectance and architecturallyderived, insulating layers of air. Some researchers of the Duke University have done some research on the desert snail investigating the way in which that snail survive, and founded that the secrete lies behind the shell locating on its back. Its form and structure provide it the life temperature. In fact, this type of snail can live in temperatures as high as 50°C, while its death point is at 55°C.
Figure 1
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ii. Termite Mound The internal structure of above-ground macrotermite mounds facilitates gas exchange in the below-ground nest by harnessing external wind energy. Mounds of macrotermitine termites maintain homeostasis through tunnels, chimneys, and use of wind creating pressure fields. Macrotermitine termites construct mounds that maintain a constant internal temperature due to their structure and interaction with the local environment, rather than use of expensive, external energy sources. Several factors allow mounds to stay 87° F inside--the optimum temperature for the fungi these termites cultivate--while the temperature ranges from 35° - 104° outside.
Figure 2
iii. Cactus Another organism which has adapted to dry, arid climates is the cactus, which has also been mimicked in design. Cacti stay cool by having ribs and spines that provide shade and enhance heat radiation. Cacti found in the deserts allow very less moisture to be absorbed from them and remain shaded due to their unique shape which can be applied in the buildings as well.
Figure 3
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3. Theory 3.1. Snail’s Shell Remains Cool It will be a surprise to many biologists that snails are found in large numbers on the dry, barren surfaces of certain hot deserts. ―Some researchers of the Duke University have done some research on the desert snail investigating the way in which that snail survive, and founded that the secrete lies behind the shell locating on its back. Its form and structure provide it the life temperature. In fact, this type of snail can live in temperatures as high as 50°C, while its death point is at 55°C. The overall temperature of the desert is around 43°C and the surface of the earth will reach over 65°C. In order to overcome this deadly heat, the snail would stick itself to the upper part of its shell, where the air temperature is around 43°C. The shell material can reflect nearly 95% of the sunlight and absorb only 5% of it to reach a degree of 45-50°C, which is ideal for the snail to survive. Moreover, the gap between the body of snail sticking to the shell and the soil creates an air pocket that would protect it from the surface heat.‖ (Mini Project of Iran by Abdul Razzak) The present study is concerned with one such snail, Sphincterochila boissieri, which occurs in the deserts of the Near East. Live specimens of this snail, withdrawn in the shell and dormant, can be found on the desert surface in mid-summer, fully exposed to sun and heat. The surface temperature of these deserts may reach 70 °C and more than a year may pass between rains…
Figure 4
"The maximum air temperature, reached at noon, was 42.6 °C, and the maximum soil surface temperature in the sun, reached at 13.00, was 65.3 °C. Under the snail, in the space between the soil surface and the smooth shell, the maximum temperature was 60.1 °C, or 5.2 °C below the adjacent soil surface in the open sun. The lower temperature under the shell is expected, for the shell provides shade for that particular spot of the soil surface on which it sits. Inside the shell in the largest whorl, located in contact with the ground, the maximum temperature was 56.2 °C. In the second and third whorls the temperature was lower, reaching a maximum of 50.3 °C. 16
Biomimetic Response to Climate
It is important that the animal, when withdrawn, does not fill the shell and leaves most of the largest whorl filled with air…The snail, withdrawn to the upper parts of the shell, is significantly cooler…
Why does the snail not heat up to the same temperature as the soil surface? The answer lies in its high reflectivity in combination with the slow conduction of heat from the substrate. Within the visible part of the solar spectrum (which contains about one-half of the total incident solar radiant energy) the reflectance of these snails is about 90%. In the near infrared, up to 1350 nm, the reflectance is similar to that of magnesium oxide and is estimated to be 95%. In the total range of the solar spectrum, therefore, we can say that the snails reflect well over 90% of the incident radiant energy. …heat flow, however, is impeded by two important circumstances. Firstly, the snail shell is in direct contact with the rough soil surface only in a few spots, and a layer of still air separates much of its bottom surface from the ground, forming an insulatng [sic] air cushion. Next, and perhaps more important, the snail is withdrawn into the upper parts of the shell and the largest whorl is filled with air; this constitutes a further impediment to heat flow into the snail." (Schmidt-Nielsen et al. 1971:385, 388-9)
Figure 5
How desert snails survive high temperatures: The surface of the shell is highly reflective, resulting in 95% reflectance within the near infrared, 90% in the visible spectrum (a). While the maximum air temperature might reach 43 °C (109 °F) ,surface temperatures can reach 65 °C (149 °F). However, shading and the rough surface of the soil results in a temperature of 60 °C (140 °F) (d). During the heat of the day, the snail retreats into an upper whorl where the temperature is an even cooler 50 °C (122 °F) (b). Heat flows in the direction of lower temperature, result in heat flow through the shell, with resultant decrease higher in the shell. - Biomimicry 3.8 Institute.
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3.2. Termite Mound Is Well Ventilated
Figure 6
The mounds' thermal mass has sufficient heat capacity to buffer the internal environment from heat gain during the day with cold accumulated over the night; narrowing shafts rising through the mound channel and accelerate the release of warm internal air out vents at the mounds’ top; and openings at the base of the mound allow cooler, denser air to flow in replacing warmer air as it rises. Mound building termites construct vertical mounds out of soil, saliva, and dung. Though mound structure can vary among termite species, but the mounds generally resemble chimneys, with some mounds having large vents while others lack large openings but have porous walls. Inside these mounds, worker termites are able to dig a complex array of tunnels of different sizes. The termites themselves stay in nests below ground in colonies that can have up to a million individuals. Some researches on termite mounds suggest that they function much like the lungs of mammals and act as accessory organs for gas exchange in the nests. It was previously thought that termite mounds functioned to maintain the nest’s internal temperature within a narrow range to tackle the extreme outside temperature fluctuations, but research on the mound-building termite Macrotermes michaelseni expands the understanding of mound function. The changes in the internal nest temperature are less extreme during the day than changes in the outside temperature, but over the period of a year, nest temperature varies and closely follows the temperature of the surrounding soil. The soil has a large thermal capacity, which means it can absorb or lose large amounts of heat energy before experiencing any changes in temperature. Hence, the soil around the termite nest is like a ―buffer‖ against daily changes in the outside temperature. 18
Biomimetic Response to Climate
ď€
Figure 7
"The macrotermitine termites build some of the most spectacular animal-built structures on the planet. Some, like the mound of Macrotermes michaelseni...are dominant landscape features over much of southern Africa. These termites control a significant portion of the flows of carbon and water through arid savanna ecosystems. These remarkable structures are not the residence for the colony--very few termites actually are found in them. Rather, they are accessory organs of gas exchange, which serve the respiratory needs of the subterranean colony, located about a meter or two below the mound‌Functionally, these mounds are devices for capturing wind energy to power active ventilation of the nest. They are adaptive structures, continually molded by the termites to maintain the nest atmosphere. This ability confers on the colony emergent homeostasis, the regulation of the nest environment by the collective activities of the inhabitants." (Turner 2000) "Heat generated by the termites and their gardens in the core of the nest flows into the collecting pipes and rises in the chimneys at a rate of about five inches per minute. As this humid CO2-rich air flows up the chimneys it draws cooler air in through the cellar area under the nest, where it begins to flow up into the various chambers‌The buttresses are riddled with tiny holes too small even for the termites but large enough for the warm stale air to diffuse out while cooler fresh air percolates in." (Gould and Gould 2007:139)
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3.3. Cactus’ Ribbed and Spined Structure Keeps It Shaded
Figure 8
Figure 9
What makes the cactus so unique is the technology it uses in order to survive. The main characteristic of a cactus is the spines that cover the entire plant. These spines serve many purposes. Protection is the obvious purpose and it makes it very dangerous and difficult for herbivorous animals to eat the plant. They also channel the rain water down to the base of the plant where the water gets collected and stored. As most cacti live in areas that receive very little rainfall, it is very important that it takes advantage of capturing water whenever there is opportunity. But the most important function that the spines serve is helping in shading the plant from the harsh sun. By having so many spines throughout the exterior skin, it shades the plant to keep the internal temperature low enough so that the water that the plant stores does not evaporate. This is the key for surviving in such an extremely hot and arid climate. Can these technologies, if implemented, influence the design of a building? "The same applies to the intricate structural designs of cacti, which are exposed to a great deal of heat pressure in the desert. Their heat-reflecting capacity is low, since their surface is greatly reduced so as to cut down on evaporation. Nature has solved the problem by equipping many cacti with cooling ribs. These shade the torch cactus's surface against the scorching sun and simultaneously improve heat radiation. The alternating planes of light and shade of the vertical cooling ribs of the torch thistle produce rising and falling air currents, which improve heat radiation. And when the sun reaches its highest position, it hits the torch thistle from above, where it presents its smallest surface. A botanist discovered that torch thistles perish of burns when they are placed horizontally in the sun." (Tributsch 1984: 136)
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Figure 10
Figure 11
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4. Applications in Architecture 4.1. Shell According to a mini project done by a student of Abdul Razzak Kalsekar Polytechnic Institute, the snail’shell can be replicated in the deserts like Iran to achieve thermal comfortability in such harsh environment. In the following some of the characteristics of this architectural form are demonstrated, which would result in better living conditions for its in habitants:
It’s curved shape results in the minimum surface exposing to the sunlight. Its spiral form, shaped from duplication of a unit pattern, provides the maximum shade on and underneath its surface. The depth of the shell allows the snail to mount to escape from the heat below.
According to these principles, some models were built up of paper ribbons curving in a way that would make the maximum shade on another. In order to find the best composition of the form, a number of paper models were built in different combination of curves, which were all common in mimicking from how the shell of the snail is organized. Then after, the conceptual designs were examined by modeling the concept in the Ecotect Building Analysis software published in 2010 by Autodesk. The weather data of the city of Yazd, one of the cities located in the central desert of Iran was loaded and analyzed. The outcome shows how well the snailinspired form would perform in tough conditions of arid areas.
Figure 12
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We have to look for shadow in desert. The sunlight beams make every object over heated in desert and the be stand cheapest way is to make shadow. In order to do that, the shells were formed and investigated in various positions to reach to the most efficient shading of the form. The shells can provide shade for each other and the whole building as well, as the spiral shell of the snail acts. The purpose of design is to make human comfort zone by minimizing the solar radiation, moisturizing and ventilating. As can be seen the upper grids shows the percentage of thermal dissatisfaction under the shells which us far less than the environment and the lower grids was the value of incident radiation of the sun under the shells which is ideal for the design.
Figure 13
The concept was modeled in Ecotect Building Analysis published by Autodesk in 2010 and the weather data of Yazd city, which is adjacent to desert, were loaded from Weather Tools and the thermal comfort and sunlight radiation were analyzed. The result was successful.
Figure 14
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Figure 15
Figure 16
In this form the space left between the shells is where the life flows. As it is shown in the section, different spaces with different requirements can be adjusted to the form. Semi-open spaces provide the possibility of making a micro-climate in which more plants can survive and help the thermal comfort achieved more easily, as the courts in traditional architecture did. Also, ventilation is a vital factor in designing of a building in hot and dry climate, semi- open spaces will help better ventilation for the building as they provide a cooler bufferzone, acting as a filter for the air entering the building. 24
Biomimetic Response to Climate
Figure 17
As we face with hot summer and cold winter in desert, the architecture should apply a multifunctional attitude through design and provide the possibility of using spaces for different purposes. This is generally done by locating spaces near to or far from the effect of sunlight.
Considering India According to his study, this design of architectural form cannot be implemented in India because; this design is well suited for zones or places which has high temperature. If we consider Rajasthan {India}, although Rajasthan has a relatively high temperature as compared to rest of India but Rajasthan still receives good amount of precipitation. The place where this architectural form is going to come up should have high temperature and less amount of precipitation or rainfall. Considering rest of the world This design can be implemented in the parts of the world where the temperature is high and amount of rainfall is also less such as the hot deserts like the Sahara desert, the Taklimakan desert, the Gobi desert, the parts of Egypt and Saudi Arabia etc.
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4.2. Mound
i.
Eastgate Centre
One of the most unusual and innovative examples of a structure utilizing traditional technology might be architect Mick Pearce’s Eastgate Centre, a shopping center in Harare, Zimbabwe, that was inspired by a 1992 BBC television program on termites, hosted by naturalist David Attenborough. Pearce was struck by the termites’ use of the thermal capacity of the ground and the mound, and their labyrinths of ventilation tunnels. ―The termite mound which we see above ground is a breathing and air-conditioning system like the human lung,‖ he says. The building is using the same principle of regulating temperatures as the termite mound, where the termites continuously open and close heating and cooling vents all over the mound throughout the day. The Eastgate Center, built in Harare, Zimbabwe, in 1995, uses about 35% of the energy required for temperature
regulation as similar conventional office buildings and saved building owners USD 3.5 million up-front, because they did not need to buy an air conditioning system for the building.
Figure 18
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Figure 19
Pearce says it took about three years to optimize the timing of the daytime and night- time fans to align with diurnal differences in temperature. ―It was like tuning an organ built into a church, where the building resonance is important,‖ he says. ―Another factor was the occupation of the building, where— like the termitary, the occupants’ heat [output], is crucial to the cycles.‖ According to Pearce, Eastgate uses 10% of the energy of comparably sized air-conditioned buildings in Harare.
ii.
CH2 Building
Another building by Pearce is also designed on the similar principles and is called the CH2 building in Melbourne. It is another example of termite mound mimicry for higher efficiency in building performances. Melbourne Council House 2 (CH2) is a multi-award winning and inspirational building that has reduced CO2 emissions by 87%, electricity consumption by 82%, gas by 87% and water by 72%. The building purges stale air at night and pulls in 100% fresh air during the day. The building exterior moves with the sun to reflect and collect heat, and turns sewage into usable water. The building has improved staff effectiveness by 4.9% and will pay for its sustainable features in a little over a decade.www.c40.org
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―Like Eastgate, CH2 is cooled by a timely management of the difference in temperature between night air and day air. In this case, a whole side of the building is opened up to direct air intake through automatic shutters made from recycled wood (left). This ―night purge‖ vents the warmer air directly from the office and shop spaces and cools down the overhead mass of concrete. The warm air rises up to openings in the ceiling and travels through hollow floors to a vertical shaft and eventually to roof vents. This passive treatment alone is enough to keep the spaces comfortable for a part of the day. Cooled fresh air rises up through floor registers throughout the day.‖ (greenbiz)
Figure 20
Figure 21
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Biomimetic Response to Climate
Figure 22
Figure 23
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Biomimetic Response to Climate
Figure 24
Council House 2 is a 10-storey office building for about 540 City of Melbourne staff, located at 240 Little Collins Street, Melbourne Australia. It has ground-floor retail spaces and underground parking and was officially opened in August 2006. CH2 has been designed to copy the planet's ecology using the natural 24-hour cycle of solar energy, natural light, air and rainwater, to power, heat, cool, and water the building.
Figure 25
Figure 26
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Biomimetic Response to Climate
Figure 27
4.3. Cactus The most important function that the spines serve is to help shade the plant from the intense sun. By having so many spines throughout the exterior skin, it shades the plant enough to keep the internal temperature low enough to where the water that the plant stores does not evaporate. This is the key for surviving in such an extreme climate. Aesthetics Architects in Thailand designed a building in Qatar that uses these technologies to create a unique sustainable solution to a complex problem. The new Minister of Municipal Affairs and Agriculture office (MMAA) in Qatar is going to be a first of its kind. Aesthetics Architects was looking for inspiration to design a building that would be situated in the hot, dry climate of Qatar, an area that only receives approximately 3.2 inches of rainfall annually. They decided to investigate the cactus for ideas on a building solution.
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.
Figure 28
The new MMAA building was designed based on the shading properties of the cactus’ spines. It achieves this by incorporating sunshades on the exterior of the building. Much like in Kieran’s analysis on a buildings envelope and a filter, these shades act like filters with the sunlight that is penetrating the spaces. With the intensity of the sunlight that beats down onto the building and its occupants, a normal building would have to have a large cooling system in order to make that space comfortable for the user. Minister of Municipal Affairs and Agriculture office in Qatar The sunshades on the MMAA building however have the ability to automatically fluctuate up and down, depending on the desired interior temperature, to regulate the amount of sunlight and heat that is transferred into the space. This innovative solution allows this building to lower the size and amount of artificial cooling necessary for the building to operate properly as well as providing a sustainable solution that is aesthetically pleasing. (Thesis, Biomimicry: using nature as a model for design)
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5. Conclusion Biomimicry can provide passive ways to tackle the heat and the nature’s strategies to respond to the climate in an architectural way can help us design low energy consuming buildings. This research studies three organisms and suggests related forms and mechanisms as a solution to climatic problems.
5.1. Snail Shells Can Be Replicated In Hot Climate
Figure 29
It can be concluded that the form of the snail’s shell is such that is can provide appropriate shade, buffer and comfort to the snail, even at a very high temperature and a built form inspired by this structure will be successful in providing comfort to a great extent. But as the author says that it cannot be implemented in India, this statement might be debatable because the form’s ability to shade and provide insulating layer of air at the bottom can be utilized in the deserts of India as well. Even if precipitation is higher, the form can do its work efficiently.
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5.2. Termite Mound Design Can Help Save Energy
Figure 30
The termite researchers are studying mounds to understand exactly how mound structure facilitates gas exchange in the colony underground. It appears that a mound’s structure enables it to store wind energy from the unsteady dynamic airflows outside the mound. Rather than generating continuous airflow through the mound, this wind energy promotes mixing between air in the mound and air in the nest, hence facilitating gas exchange in the nest. This detailed understanding of macro termite mound structure and function could inspire new biomimetic technologies in energy-saving climate controlled systems. The mechanism of ventilation in the termite mound is a great example to learn from. The East Great center shows how successful it can be to implicate the design into our buildings. It is very environment friendly and energy conserving.
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5.3. Cactus Can Inspire the Structure of a Building
Figure 31
The shape of the torch cactus can be well utilized to provide shading in buildings and minimizing the surface area of contact with the sun.
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5.4. A Combination of All Three There can also be done a study over the combination of all the three forms in one building to further enhance the results of thermal comfortability. The white reflective and spiral surface of Snail’s Shell’s form, the ventilation mechanism of Termite’s Mound through the provision of holes and the torched shape of the Cactus can all be applied together which may provide the maximum thermal comfortability in hot climates.
Figure 32
Figure 33
Figure 34
Figure 35
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Bibliography Research Papers
Shaikh Nawaz Altaf (2012) : Bio-Mimicry of Snail, department of civil engineering, Anjuman-I-Islam’s Abdul Razzak Kalsekar Polytechnic Michael J. Maglic (May 2012) : Biomimicry: using nature as a model for design, Graduate School of the University of Massachusetts Maibritt Pedersen Zari (2007) : Biomimetic approaches to architectural design for increased sustainability School of Architecture, Victoria University Pedersen Zari, M. (2008). Bioinspired architectural design to adapt to climate change
Internet sources
Shell protects from heat: desert snail http://www.asknature.org/strategy/1683ae77eb0b8030d6c81e7098ddcd3c Shape shades and enhances heat radiation: cactus http://www.asknature.org/strategy/0aaa42953466bee0b1f530ac73a28312 Mound facilitates gas exchange: mound-building termites http://www.asknature.org/strategy/8a16bdffd27387cd2a3a995525ea08b3 Cooling concepts alternatives to air conditioning for a warm world, Environmental Health Perspectives volume 121 | number 1 | January 2013
Books
Desert snails: Problems of heat, water and food by Knut Schmidt-Nielsen, C. R. Taylor* and Amiram Shkolnikf Department of Zoology, Duke University, Durham, N.C. (Received 18 March 1971)
Google Books (2008) The Architecture Annual 2007-2008. Delft University of Technology https://books.google.co.in/books?id=8MSmD7r3RlsC&pg=PA54&lpg=PA54&dq=biomimetic+respons e+climate&source=bl&ots=rYPtVkHmda&sig=5bHTVUBNJ-jXgSpcYjwLeVmGxE&hl=en&sa=X&ved=0CFUQ6AEwCWoVChMIocyhoqvCxwIVjXKOCh2SRwp#v=onepage&q=biomimetic%20response%20climate&f=false Google Books (1997) Biomimicry - Innovation Inspired by Nature https://books.google.co.in/books?id=mDHKVQyJ94gC&printsec=frontcover&dq=innovation+inspired+ by+nature&hl=en&sa=X&ved=0ahUKEwjk8a_iq_PMAhXCKJQKHTSAbcQ6AEIHDAA#v=onepage&q=innovation%20inspired%20by%20nature&f=false
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