Defining Biomimicry: Architectural Applications in Systems and Products
Emily Royall
Instructor Werner Lang
csd Center for Sustainable Development UTSoA - Seminar in Sustainable Architecture
2 UTSoA - Seminar in Sustainable Architecture
Defining Biomimicry: Architectural Applications in Systems and Products
Emily Royall
main picture of presentation
Fig. 01 Artwork by Dale Chihuly, photographed by Thomas Hawk
Introduction generating residual, inactive waste. Where biological processes are Biomimetics or Biomimicry is a continuously evolving to manipulate fashionable term whose ultimate hydrogen, carbon and oxygen to definition continues to evade us. The accomplish their objectives, humans purpose of this paper is to outline have cheaply contracted the unsus- a concrete theoretical and practical tainable power of oil. Biomimetics definition for Biomimicry and high- seeks to remedy such error design- light its architectural applications. ing efficient systems and products. In effort to clarify the Biomimetics Biomimicry is a spiraling, continuous process and illuminate its relation- process, taking nature as inspira- ship to sustainability, the Biomimicry tion to generate “organs” (individual “helix” will be introduced as a con- products) or “organisms” (systems tinuous model illustrating two integral and processes) for the purpose of products of the Biomimicry process: integration into a sustainable sys- organs and organisms. The “organs” tem. For example, Biomimicry could and “organisms” of Biomimicry will produce advanced photovoltaics (the be explored in reference to photovol- organ) inspired by photosynthesis, or taics and urban planning, citing dye a “smart house” system (the organ- sensitized solar cells and the sus- ism) modeled after bee algorithms, tainable city, Hammarby Sjöstad, as for the purpose of integration into case studies. a sustainable energy system. The model below illustrates this concept What is Biomimicry? using a double helix.
Nature has already solved many of the mechanical and structural problems humans face today without
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lem solving. The typical conception of Biomimicry is often oversimplified
Y into a linear process. First one asks the initial question, “How does nature R o solve my problem?” then observes r g C a the solution in nature, creating a de-
I n sign that mimics the observation. For i s this misconception, Biomimicry has
M m been severely criticized. I suggest
I that what separates Biomimicry from standard problem solving is its con- n s u M s t a tinuous, spiral-like nature, providing i n a b
a i l i t y no definitive solution, only products
O g
r and systems which can adapt to a I o changing environment. Additionally, Biomimetics is typically mistaken for B
biotechnology. Biomimetics is not
biotechnology because it does not implement “bio-assisted” processes Figure 02: The Biomimicry Helix Model by (such as using green algae to treat Emily Royall waste water). Finally, Biomimicry ity, integrates the organs and organ- is also often confused with art and The helix model of Biomimicry isms produced by Biomimcry into a aesthetics. Artists reproduce existing reflects a number of nuances. Pri- continuously evolving system. This patterns in nature for an aesthetic marily, the model is a spiral. This integral relationship with sustainabil- effect. This is not Biomimicry as the represents the idea of Biomimicry ity is also relatable by a basic biologi- organ created is not integrated with as a continuously evolving process, cal rule: nature seeks to minimize an organism in a sustainable system. infinitely seeking a closer fit to the the amount of energy consumed in a The organism product of Biomimicry ever-changing environment. The spi- given period of time (E/T). is the subject of the next section. ral reflects the continuous feed back and repeated fine tuning required to To understand the broad applicability The Organism adapt “organs” and “organisms” to of Biomimicry, it is helpful to consider the environment. Notably, the spiral nature as a mentor, measure and The process of Biomimicry yields motif is an important structural build- model. “organisms” in the sense that nature ing block in nature and is encoded can inspire the design of efficient into ourselves and environment. As Mentor: We can view nature not systems. As mentioned earlier, bio- Secondly, “organs” and “organisms” as a possession, but as a teacher. logical systems (and efficient man- make up the two strands of the helix, made systems) seek to minimize the reflecting their entwined equality. As Measure: We can use nature as amount of energy consumed over Organs include singular products an ecological standard to measure time. Because this basic concept is such as photovoltaic cells or fiber the fitness of our own designs. inherent to all sustainable systems, optics, and organisms are systems Biomimicry on this level can have such as smart grids or cities. Bio- As Model: Biomimicry studies na- applications for many fields including mimicry is equally capable of yielding ture’s models and emulates these government and business mod- both kinds of items. Finally, note the forms or processes. els. Business models can fashion branches of the helix connecting the themselves after natural processes organ and organism strand. These There are however, a few problems which are “waste-free, cyclical, and are “sustainability” branches, em- with Biomimicry. It is difficult to seg- very efficient, running on sunlight, phasizing the mutual dependence of regate Biomimicry from basic prob- use only what it needs, and focus- organs and organisms. Sustainabil-
4 Defining Biomimicry: Architectural Applications in Systems and Products
ing on resource productivity.” The Density:Dense metropolitan areas is expended when individuals travel context of this paper will deal with a show lower rates of vehicle own- shorter distances for the services more architectural application to the ership and usage. A nationwide they need. The centralized infrastruc- biomimetic production of systems; analysis of vehicle miles traveled in ture of an urban area contributes to urban planning. the U.S. revealed that the top ten the reduction of carbon emissions largest metropolitan areas produce and convenience of city-dwellers. In relating biology to urban plan- 23.5% of the total vehicle miles trav- Many biological systems such as ning we can reflect on the principles eled (VMT), while housing 26.3% of plant or animal cells operate on the illustrated by Richard Hopper in his the national population, reinforcing same principle, often minimizing 1970s article published in the Ameri- the notion that metropolitan resi- the distance of resources in effort to can Planning Association magazine. dents drive less than the average reduce E/T. Hopper suggests that all man made American. Additionally, although total and natural systems have inherent driving is concentrated in metropoli- In essence, metropolitan cities are carrying capacity that can be tan areas, the greatest driving per sustainable for much of the same person occurs in low density South- reasons that biological systems are 1. used as a limit for growth western and Southeastern regions. sustainable. Seeking to minimize en- The spread of urban sprawl notably ergy consumption over time, natural 2. ignored and exceeded with the conse- quence of degrading the system requires more energy usage per systems appear to use analogous capita and does not minimize E/T. mechanisms that humans have 3. expanded through new technologies and Austin, Texas is no exception. An created, (or have naturally evolved) methods of design or planning Austin resident will drive an average to solve similar efficiency problems. of 31.1 miles per day. The percent- Such is a credit to the concept of Essentially Hopper makes an argu- age of commuters walking to work Biomimicry which evidently, is not ment that is appropriate to Biomimic- is only 2.2%, and the percentage of entirely foreign. Naturally and histori- ry. In developing a sustainable urban commuters using Transit is a dismal cally, humans have built cities limited blueprint, one must include basic bio- 2.8%. Ironically, Austin ranks above by the land, exhibiting Hopper’s logical rules in mind. Hopper states average when measuring the extent principles of energy ceilings as well that there is a limit to the growth of of urban sprawl compared to other the biological principles of sustain- a system before it becomes unsus- major metropolitan areas. ability. Cities built before the indus- tainable (or exceeds energy over trial age of the 19th century were far time), and if this energy ceiling is Specialization:This is an area vital to more modest in their energy de- ignored the system may be degraded city life. Diversity of a city including mands. They were built into the land, over time. Additionally, the potential the specialization of retail enterprises integrating nature and industry as a energy ceiling of a system can be ex- and civic centers is fundamental working rural and urban landscape. panded through innovative technol- for the incubation of new ideas and Ancient European cities had com- ogy. These basic principles illustrate enterprises so prized in major metro- mon business areas, central squares the natural relationship between politan areas. The diversity of a city and localized infrastructure reducing cities and nature and providing some is made up of a plethora of special- the need to travel long distances for insight into the sustainability of met- ized parts, contributing to the city’s resources. These cities even oper- ropolitan areas. flourishing economy and society. ated on a cyclic system, using the Similarly, the life of an ecosystem is land to produce food and energy for Cities and Biology stimulated by the specialization of settlement activity which naturally a variety of interconnected partici- incurred waste that was once again What makes cities sustainable? pants. Specialization allows a system reapplied to the soil. Such cities of There appears to be popular consen- to be self-sufficient, relying primarily the past were fueled by solar power, sus that three principles define the on the goods and services of the illuminated at day break and end- sustainability of the urban frontier: localized system. ing activity at night fall. Ironically the Density, specialization and localized contemporary sustainable movement infrastructure. Localized Infrastructure: Less energy fashions itself as a novel trend, while
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Figure 04: human lungs Figure 03: veins in a leaf Figure 05: satellite image of a river basin the basic principles of sustainability dioxide is generated as waste, but is whether political, economical or appear to be “going back to nature.” transformed into reusable products. environmental. In this way, a city is Additionally, the old infrastructure continually evolving, and so too must Cities and Cells of a cell (worn out components) is its sustainable infrastructure. Con- broken down by structures called trary to the implication of its title, the Biomimicry shows great potential for lysosomes, and recycled for further sustainable movement is a perma- urban planning. Imagine a city mod- use. The deconstruction and reuse of nent process much like the Biomim- eled after a cell. Although this design materials, as opposed to demolition icry Spiral model introduced earlier. remains conceptual, a number of has worked favorably for urban envi- Sustainable infrastructure must realistic applications can be inferred. ronments, avoiding typical demolition therefore consistently seek a closer This hypothetical city would possess costs ($50/ton or more) and reducing fit to an ever-changing environment. as a cell does, three major charac- building costs. Cities could The addition of a bulky photovoltaic teristics: also potentially mimic cellular trans- cell is not necessarily a sustainable port, where transportation within the technology as it does not provide 1. self-sufficiency cell uses locally produced energy. facile alteration or adaptation to its 2. porosity surroundings. Nothing is sustainable Yet despite their self-sufficiency, both forever. 3. adaptability cells and cities must adapt to their environment and retain an element Defining how flow systems change Consider the potential architectural of porosity. Cells respond to internal over time, Constructal Theory applications of the following con- and external changes in their envi- highlights how a system must be cepts. ronment and also depend crucially architecturally designed to ensure on effective communication systems survival. Constructal theory operates Cells are largely self sufficient as re- and signaling. Like a city, a cell’s “in- on a basic rule: flected particularly by their organiza- ternational” communication is equally tion. A cell is contained; its contents as important as its local communica- For a system to survive it must spread only to the plasma membrane tion, allowing for the organized func- evolve to provide increasingly easy limits. This way, components of the tion of a unified system. access to the currents that flow cell do not have to commute large through it. distances to achieve their purpose. Evolution of Cities Resources are localized and orga- Although seemingly abstract and ir- nized, without unnecessary repetition Cities like any other organism can- relevant, this rule elegantly illustrates of infrastructure. As in a city, carbon not remain stagnant in any climate why some systems thrive and others
6 Defining Biomimicry: Architectural Applications in Systems and Products
fail. For any of these systems to (perhaps unknowingly) in a similar tion, whereas one third of trips are sustain or survive, they must be ar- manner to a cell via its self-suffi- car-borne. Taking advantage of chitecturally designed in such a way ciency, porosity and adaptability. It localized resources, one of the major that the elements within that system is an example of how designers are transportation options is a free public increasingly get to where they need already applying Biomimicry without ferry operating between the northern to go. Figure 3 through 5 illustrate even knowing it. to southern borders of the city. One constructal theory. fourth of residents report using the Hammarby is currently home to ferry regularly. Despite these options, Here, we see the physical evidence some 25,000 residents in 11,000 66% of residents still own a car. that human lungs and a river basin apartments located in a southeastern Hammarby has therefore encour- have both evolved to in the optimal pocket of Stockholm. The project is aged carpooling, and the city expects way to get their materials where they expected to be completed in 2015, at least 15% of residents to par- need to go (oxygen in the case of the projecting 35,000 individuals to live ticipate by 2010. Currently 8% (270 lungs and water for the river basin). and work in the area. Historically, the residents) participate in the program. Over time these two systems adapt- port area was a small-scale industrial ed to a changing atmosphere, finding “shantytown,” dotted with temporary Energy: Energy will come from the the maximum fit of their objectives to infrastructure largely consisting of waste and the sun. Hammarby’s the environment; sustainability in a corrugated steel shacks. In 1998 this entire heating supply is based on nutshell. area was demolished to make room waste or rewnewable energy sourc- for a sustainable city. Several fea- es. Hammarby’s district heating and Another biological example of Con- tures of Hammarby Sjöstad make it cooling is centralized. The combined structal Theory can also be found in an excellent example of the potential heat and power plant uses com- native grass prairies whose flexibility of Biomimicry in urban design. bustible waste as an energy source of dominating grasses between wet (biofuels), producing electricity and and dry seasons allow the species to Self Sufficiency district heating. Additionally, the “redraw” the system to accommodate Hammarby heat plant extracts waste environmental changes. This simply Construction: Hammarby focuses heat from treated wastewater in the illustrates that to ensure any man on using localized resources and Henriksdal wastewater treatment made system’s survival, we must recycled materials for building con- plant. District cooling is provided maintain the flexibility to recognize struction. Similar to how lysosomes by the Hammarby heat plant heat important changes and reserve the in a cell recycle existing material and pumps, where heat is exchanged freedom to “redraw” our designs. reuse relevant resources, Hammarby into water cooling. In this way, cool- This directly applies to urban plan- Sjostad has outlined procedures to ing is a byproduct of district heating. ning and architecture in the sense draw materials from the demolition Solar cells and building integrated that designers and architects should site. Pressure treated timber may not photovoltaics have been installed for consider the elasticity of their de- be used for construction, and Copper the collection of energy. The energy sign. Can the design accommodate is not used as ducting material. from a 1m² solar cell module produc- change? Is the building material es 100 kWh/year, corresponding to flexible enough for alteration? To Transportation: Unique and efficient the domestic electricity requirements ensure the survival of an urban transportation options within the city of 3m² residential floor space. development, urban planners should reduce the amount of energy con- consider the potential for adaptation sumed and minimize CO2 byproduct. Water: Water is a valuable, moni- and evolution of their design. Hammarby Sjöstad expects 80% tored resource in both a cell and a of residents’ and workers’ journeys city. The installation of water-saving Case Study: Hammarby Sjöstad to be by public transport (via the washing machines, dishwashers, low light rail “Tvärbanan”), on foot or by flush toilets and air mixer taps have In the outskirts of Stockholm lies bicycle by the year 2010. As of today, reduced the average water use of Sweden’s hailed “sustainable city,” two thirds of residents participate an individual by 25%. Hammarby’s Hammarby Sjöstad. It functions in alternative forms of transporta- goal is to reduce water use by 50%,
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from 200 litres per person per day to 100 litres within the next few years (Average water use figures are based on the Stockholm average). Using a new water treatment system, 95% percent of the phosphorous and nitrogen extracted from waste water is recycled on agricultural land. Ad- ditionally storm and drainage water from urban runoff is treated and reused.
Waste: Hammarby operates on a cyclic system reminiscent of efficient cities of the past. Waste is reused for the soil treatment and the production of biofuels and biogas, used to run transportation systems and appli-
Figure 06: Map of Hammarby Sjöstad
Figure 08: Waterside view of Hammarby Sjöstad
Figure 07: Map of Service Locations
Figure 09: Interior of Hammarby Sjöstad
8 Defining Biomimicry: Architectural Applications in Systems and Products
Figure 10: Architectural applications of Biomimicry. Left: The Eastgate Centre in Harhare, Zimbabwe. Right: self-cleaning paint by Lotusan ances. Hammarby implements a financial incentives encouraged busi- The Organs multilevel waste management model. nesses to open before the market Combustible waste is transported to had fully developed, an impressive Organs help organisms to function. the Högdalenverket where it is incin- initiative. Finally, Hammarby Sjöstad Without efficient organs, a system erated and recycled as heating and has excellent public spaces, with a cannot be considered sustainable. electricity. Food waste is transported permeable street pattern as well as Biomimicry is capable of not only to Sofielund where it is composted an extensive network of parks. Ham- constructing theoretical concepts and into soil with the ultimate goal of be- marby has indicated that efficient processes, but also tangible ing converted at least 15m² of courtyard space products. Biomimicry is best known into biogas and bio-fertilizers. News- and a total of 25–30m² of courtyard for the organs it produces, which papers and packaging are recycled space and park area must be within unfortunately are often gadgets into other products, and electronic 300m of every apartment. Addition- advertising idealistic technology. The waste is disassembled and reused, ally, at least 15% of the courtyard goal of this section is to illustrate the though unusable excesses are de- space is sunlit for at least 4-5 hours practical applications of the physical posited in landfills. Hazardous waste during the spring and fall equinoxes. products Biomimicry can generate. is incinerated. Adaptability Architectural Products: Biomimicry Porosity can yield concept designs for general The city has emphasized its role as urban planning as well as site-spe- The master plan of the city was a a “laboratory” testing new building cific infrastructure. One particularly collaborative effort, inviting the par- techniques, water purification sys- innovative example is the Eastgate ticipation of over 20 architects and tems and evaluating new technology. Centre in Harare, Zimbabwe de- designers. Though it is self sufficient GlashusEtt is the city’s education signed by architect Mick Pearce. and enclosed, the city is not cultur- center. Here officials and residents The nation’s largest shopping mall is ally or economically exclusive. The can meet to discuss the future of the modeled after a termite mound indig- Masterplan team effectively aspired city while addressing current issues enous to the area, using a passive to create a new inner city district, and developments. The education heating and cooling system. Termites designing extensive waterside units center reflects recognition of sus- build large mounds that must be kept with floor to ceiling heights encour- tainability as a continuous process, at precisely 87 degrees F despite aging retail. The high density de- constantly requiring open discussion exterior temperatures ranging from velopment creates an urban district and flexible remodeling. 35 to 104 degrees. The termites that can sustain a range of shops achieve this by constantly opening and services. Planning policy and and closing a series of heating and
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cooling vents throughout the mound own fiber optics and are better ca- over the course of a day. The system pable of transmitting light than indus- is carefully adjusted to convection trial fiber optic cables. Additionally, currents, sucking up air in the lower Venus Sponge fibers are produced part of the mound down into marginal at low temperatures using natural enclosures and back up through a materials and are more flexible than channel to the peak of the termite the man-made variety. A study of the bound where heat is released. The way this species generates its own Eastgate Centre, primarily made of fiber optics could reveal how humans concrete, operates in a similar way could make stronger, more efficient where outside air is either warmed fiber optics at ambient temperatures. or cooled by the concrete, vented Another example of Biomimicry’s through floors and offices, and ulti- contribution to automation systems is mately escapes in ceiling vents. De- the Smart Switch developed by RE- velopers of the Eastgate Centre have GEN Energy, which manages energy saved 3.5 million dollars from not mimicking the swarm bee logic of installing an air conditioning system self organization. The goal is to avoid alone. These savings have trickled simultaneous energy demands from down to the tenants, whose rents are appliances without sacrificing indi- 20 percent lower than those of other vidual performance. The product at- commercial buildings. taches to the electric box of a home and communicates with household Figure 11: Dyesol Panel Automation Systems: Biomimicry has appliances, turning off unused ap- shown increasing promise for the pliances as needed without human automation systems industry. Smart intervention. The device is simple to Grids supply electricity to consumers install and tests have revealed that it using digital technologies in effort can reduce energy consumption by to reduce energy consumption and 30% on commercial and residential increase reliability. Fiber Optics is buildings. frequently required for the efficient display and transportation of informa- Building Materials: Biomimicry is a tion within these systems. The Venus huge contributor to the field of green Flower Basket Sponge make their building materials. One exciting de-
Table 1. Comparison of Solar Cell Materials
Figure12: DSSC as flexible thin film Solar Cell mate- Crystalline Silicon Polycrystalline Amorphous velopment is the self-cleaning paint rial Silicon Silicon Lotusan, which mimics the bumps on Embodied Energy 553 407 116 a lotus leaf used to collect water and (kW-hrs/m2) clean foliage. Tiny bumps in the paint Energy Conver- 15-22 14-15 7-10 analogously collect dirt off of the sion buildings when exposed to rainwater, Efficiency (%) allowing a façade to essentially clean itself. The self assembly of natural building materials is another promis- ing area of biomimetics research. Sandia National Labs has found a
10 Defining Biomimicry: Architectural Applications in Systems and Products
way to create a self-assembly coat- Manufactures instead harvest poly- electricity generation using lower em- ing process. Hard building materials silicon, splitting its molecules into bodied energy in manufacture and can be produced via the “self assem- Silicon via the Czochralski process at organic materials. DSSC is currently bly” or simply the interlocking of mol- high temperatures. being tested against national stan- ecules manipulated by evaporation dards by two major manufacturers, at room temperature. The potential Carbon emissions are a large con- Dyesol and Fujikura. of this already existing technology cern when considering silicon pro- is related to Photovoltaics. Imagine duction. Currently, fourteen tonnes of Cost: The market price and demand spraying the necessary precursors Silicon are required to generate one is on the rise for silicon as a result of onto a desired area and watching the mega watt of electricity. For every increasing demand from the com- materials self assemble naturally. 1 tonne of Silicon produced, 1.5 puter and semiconductor industries. tonnes of CO2 is emitted. Typically a Silicon market prices are expected Case Study: Dye Sensitized Solar Silicon based solar cell will pay back to rise considerably as polysilicon Cells (DSSC) this embodied energy in 1-5 years. A reserves (the empirical material used life cycle assessment of amorphous to produce silicon) are in decline. The most important organ application silicon PV systems showed a total When comparing total production of Biomimicry is the use of Dye Sen- embodied energy of 42 g CO2/kWh. of silicon to its usage over the last sitized PV systems. DSSC is supe- decade, we find that the total produc- rior to many Silicon based PV for in Alternatively DSSC produces be- tion of silicon is increasing while the manufacturing, cost and application. tween 19–47 g CO2/kWh, reflecting total unused has completely dimin- a great potential for CO2 emission ished. This has a negative impact on Manufacturing: There are three reduction. the future of silicon prices, contribut- major types of Silicon PV cells avail- ing to PV costs of 2$/watt or more. able on the market today; they are Currently nine producers manufac- Alternatively, DSSC projects costs single crystal, polycrystalline, and ture the bulk of silicon available on 1$/watt making it readily competitive amorphous silicon. A great deal of the market, and collective in 2006 with the coal industry. embodied energy is required in the produced 35.5 ktons of Si, effectively manufacture of a Silicon based PV emitting 53.55 kton of CO2 per an- Application: The installation and ap- cell. The following chart illustrates num (based on the above conversion plication of DSSC has a number of the embodied energy for the three factor). These figures can be related advantages over Silicon PV. Com- types of Silicon PV. to Austin, Texas. Given the current pared to silicon PV, performance of PV capacity of Austin, 3.4 MW, and DSSC varies less with temperature DSSC requires less energy for assuming the majority of PV installed fluctuations. The maximum power manufacture than each of these to date is silicon based, we can yield point voltage (Vmpp) for DSSC silicon options, though the energy a rough estimate of 71.4 tonnes of varies by 20mV over a temperature conversion efficiency is roughly 11%. CO2 already emitted by production range of -10ºC to 70ºC whereas that DSSC are manufactured at relatively of these solar cell systems. Addition- of crystalline silicon cells significantly low cost on production equipment ally, Austin Energy projects a PV decreases with increasing tempera- similar to manufacturing processes capacity of 200MW within the next ture (Murray). Furthermore the flex- used by printing industries. Addition- few years. If all these installations ible, film-like nature of DSSC makes ally, DSSC is manufactured using are silicon based PV, 4,200 tonnes of it a perfect candidate for Building In- readily available materials that are CO2 will have been emitted in their tegrated Photovoltaics (BIPV). BIPV relatively non-toxic. Ruthenium dye production. has a number of advantages and has is one of the primary materials used been shown to be more efficient than in DSSC production. An analysis of From an environmental perspective, providing a systems energy using a the availability of Ruthenium reveals the main improvement DSSC has PV power plant. DSSC can be easily reserves that are projected to last made over the prevailing silicon tech- applied to building envelopes and well over 150 years. Silicon however nology is by the increase in conver- facades, giving it much architectural is not found in nature so abundantly. sion efficiency from solar radiation to potential. DSSC can be integrated
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into southern facades, used for Sources www.glrea.org/articles/index.html>. shadowing and even incorporated Jacobs, Jane. The Death and Life of Great into glazings. Additionally a flat roof Aizenberg, Joanna, and Gordon Hendler. Designing efficient microlens arrays: les- American Cities. New York: Vintage Books, is not required for its installation, un- sons from Nature. Tech. Journal of Materials 1961. Print. like the bulky infrastructure of Silicon Chemistry, 24 June 2004. Web. 12 Defining Biomimicry: Architectural Applications in Systems and Products tron Sviluppo. Web. All Hammarbi Sjostad Images. Digital image. Hammarby Sjostad. Web. 13