Thesis: Sustainable Architecture Through Biomimicry

SUSTAINABLE ARCHITECTURE THROUGH BIOMIMICRY: Re-creating the urban tree canopy with photosynthesizing façade additions JUDY ZHANG ARCH Honors Thesis | University of Pennsylvania | Spring 2021

Sustainable Architecture Through Biomimicry: Re-creating the urban tree canopy with photosynthesizing façade additions

Judy Zhang ARCH Honors Thesis | University of Pennsylvania | Spring 2021 Advisors: Elizabeth Lovett, Architecture Lecturer Brenda Casper, Professor of Plant Biology William Braham, Director of the Center for Environmental Building + Design Charles Berman, Associate Principal at Diller Scofidio + Renfro Architects

Table of Contents INTRODUCTION

7

I. THEORETICAL FRAMEWORK

8

Biomimicry Biomimicry in Architecture Sustainable Architecture

II. SITE CONTEXT Climate Change in Pennsylvania Philadelphia, PA Case Studies in Center City Urban Heat Islands & Street Trees Macro/Micro-climatic Challenges

26

III. BIOMIMETIC STUDIES

56

CO2 Capture - Plant Leaves Heat Island Mitigation - Forest Canopy Solar Shading - Spanish Moss

IV. DESIGN

76

A Preliminary Design Re-assessment in Approach Modular Origami Tessellations

V. SYNTHESIS & REFLECTION Evaluation of Design Against Contextual Frameworks

114

Introduction

The climate emergency is one that should concern all sectors, including the fields of architecture and design. Using our creativity, we, as architects and designers, can innovate the industry and push forward genuine efforts for sustainability. We need to return to nature as our source of inspiration, learning from her in order to survive.

This thesis will approach the notion of sustainable architecture through the lens of biomimicry. In the search for building solutions that will heal our environment, it is fitting to learn from one of Earth’s original inhabitants: plants. The vast bank of wisdom within plants will inform design solutions that address the urban challenges of Philadelphia, Pennsylvania. As one of the nation’s great metropolises, Philadelphia is just one of many cities that contribute to the phenomenon of global warming through greenhouse gas (GHG) emissions. This city’s 600,000 buildings produce 79% of the city’s total GHG emissions, most of which is no longer being captured by trees due to the city’s diminishing tree canopy. With less trees, more buildings, and greater CO2 emissions within the city of Philadelphia, I propose the re-creation of the urban tree canopy using biomimetic facade additions. It is time to bring plants back into the city and curb the exacerbation of the climate crisis.

7

8

I. THEORETICAL FRAMEWORK

Biomimicry Revolution introduces an era based not “ ...the on what we can extract from nature, but on what we can learn from her.

Janine Beynus, Biomimicry: Innovation Inspired by Nature.

9

Biomimicry

For centuries, our society has grown to adopt an attitude of domination over nature. Our goal has been to conquer the wilderness, taming it so we could build civilizations, advance technologies, and project national power. Since the Industrial Revolution, we have developed an unequal relationship with nature, and we began to take more than we could give. As natural resources were extracted and exploited, the ecology of humans and nature began to disintegrate.

Published in 1997, Janine Beynus’s novel Biomimcry: Innovation Inspire

by Nature proposes a new framework to guide our relationship with nature.

Calling it biomimicry, Beynus described this practice as

“ the conscious emulation of life’s genius. ” 1

Through the respectful imitation of nature, this practice looks to nature’s strategies and processes to solve human problems. The utility of biomimicry falls within three categories: that of (1) a model, (2) a measure, and (3) a mentor. Rather than progressing our knowledge of what to extract from nature, biomimicry strives to learn from nature what is appropriate, what works, and what is valuable. In our human history, we have desired to gain independence from nature, resulting in our reliance on “human

1. Benyus, Biomimicry: Innovation Inspired by Nature, 2.

11

THEORETICAL FRAMEWORK

cleverness alone” to survive.2 But this mode of survival has begun to violate fundamental ecological laws, especially the one that calls for a species to share the resources of a niche. By ignoring this law, one species “winds up destroying its community to support its own expansion.”3 Looking at our habits of consumption and disregard for nature, we have become that species, the one that will ruin our Earth for all.

“ We began as a small population in a very large world and have expanded in number and territory until we are bursting the seams of that world.4

” Janine Beynus

The looming destruction of our world is becoming more apparent with the pressing issues of global warming, rising sea levels, and declining biodiversity. In order to survive in our quickly deteriorating world, we must look to that which sustains us - the natural environment. With its 3.8 billion years of research and experimentation, nature has become wise, amassing an immense bank of knowledge that we need to tap into. Through biomimicry, we will learn what has survived all these years and what has failed.

··· In 2006, Beynus partnered with Bryony Schwan to establish The Biomimicry Institute, a non-profit organization committed to spreading biomimetic education, research, and exploration.5 Partnering with educators spanning from grade school to the university level to even non-formal environments like zoos, this institute strives to introduce biomimicry as a crucial component of educational systems. Continuing with their mission, the Institute launched Ask Nature, a free online catalog detailing a variety of solutions from nature as well as past biomimetic projects.6 From this resource bank, one particularly interesting innovation from nature is titled “SLIPS Zero.” Produced by Adaptive Surface Technologies, this newly developed technology looks to the pitcher plant as a mentor for creating an “ultra-thin slippery surface” that would permit viscous liquids 12

2. Benyus, Biomimicry, 5.

3. Ibid.

4. Ibid.

5. The Biomimicry Institute.

6. Ibid.

BIOMIMCRY

to be emptied fully from plastic containers. This team tackled the issue of reducing waste from plastic containers, as the inability to empty out a container completely not only decreases the amount of usable content for the consumer, but it also makes the containers difficult to recycle at times.

In formulating a biomimetic solution, the pitcher plant was studied for its slippery rounded rim. This rim contains a thin wet film that reduces the friction between the plant and anything that lands on this surface - usually unknowing insects who then fall into the plant's pool of digestive liquids (Fig. 1 & 2). Learning from this plant’s adaptive strategy to capture insects, the team at Adaptive Surface Technologies developed a chemical coating that would hold a lubricant layer on the inside of container walls. Like the plant, this consistently wet film reduces the surface friction and allows liquids to slide off the container sides (Fig. 3-6). Excitingly, this invention has received a patent, and it is just one of many innovations that is spreading the practice of biomimicry to the public.7 Fig. 1. Pitcher plants

Fig. 2. Diagram of the slippery zone on the pitcher plant

7. "Ask Nature," The Biomimicry Institute.

13

THEORETICAL FRAMEWORK

Fig. 3.

Fig. 4.

14

BIOMIMCRY

Fig. 5.

Fig. 6.

Fig. 3 - 6. Screen-captures from a video provided by Ask Nature demonstrating the function of SLIPS Zero within a honey bottle.

15

THEORETICAL FRAMEWORK

However, the field of biomimicry is not just one for design inspiration.

The very nature of the practice urges us to rethink our egos and our position in the hierarchy of nature. Right now, the human world and the natural world are two separate spheres, both vying for control and survival. By integrating natural processes into our world, the boundaries between the two realms will begin to blur and merge. Biomimicry will not only equip us with new solutions, but it will also foster a mutualistic, accepting relationship between us and the non-human world. As Beynus puts it, we need to “adapt to the Earth rather than the other way around.”8

··· Moving forward, Beynus’s canon of “nature’s laws, strategies, and principles” will lie at the foundation of this thesis exploration: Nature runs on sunlight Nature uses only the energy it needs Nature fits form to function Nature recycles everything Nature rewards cooperation Nature banks on diversity Nature demands local expertise Natures curbs from within Nature taps the power of limits9

8. Beynus, 5.

9. Ibid., 7.

16

Biomimicry in Architecture

Applying principles of biomimicry to the field of architecture is not something new, and numerous architects have successfully merged the two. However, what Michael Pawlyn argues for in his book Biomimicry in Architecture is that biomimicry in the built environment is a necessity if we are to transition from an industrial age to an ecological one.10 By incorporating biomimicry as a foundational pillar of the architectural practice, Pawlyn states that we can create cities and buildings that are healthy, regenerative, and integrated in natural systems. As an architect himself, Pawlyn identifies three major goals that designers need to work toward: 1. Radically increasing resource efficiency 2. Replacing our fossil-fuel economy with a solar economy 3. Adopting a closed-loop system in which all resources circulate so as to eliminate waste.11 With such lofty goals, nature can be our crutch and mentor. In combining today’s impressive advances in scientific knowledge with all the treasures of nature, we can rely on biomimicry to help us develop innovative solutions. As Pawlyn puts it, biomimicry is “a synthesis of the human potential for innovation coupled with the best that biology can offer.”

10. Pawlyn, “Introduction,” Biomimicry in Architecture.

11. Ibid.

17

THEORETICAL FRAMEWORK

In thinking about improving the built environment, the practice of biomimicry can advance the construction industry by producing solutions that “deliver substantial improvements in performance and contribute to people’s well-being.”12 But what does such a call to action mean? To demystify this vision, Pawlyn offers an axiom:

“ more shape, less material, greater responsiveness. ” 13

The idea of achieving material resourcefulness through an efficiency of shape design comes from the years of natural evolution that have allowed nature to function efficiently with an economical use of materials. One biological example can be seen with plants, who want to maximize their leaf surface area for photosynthesis. But to maximize means to deveop larger, heavier leaves. Without a structural adaptation, a plant with larger leaves will be unable to support itself, setting up the necessity to change its leaf form. To survive, a plant can incorporate curves and folds in its leaves to increase leaf stiffness while maintaining thinness. Such shape change is eminent in the leaf of the Southern Magnolia, which features both a curve and fold for stiffening purposes (Fig. 7 & 8).14 The final part of the axiom refers to the natural tendency of living organisms to adapt to changing conditions. Transferring this idea to the built environment, deployable structures pave the way for a promising route to explore. These structures can “move, expand, or contract by changing their geometric, material, or mechanical properties.”15 Buildings do not rest in dormant environments, and so why should they remain static structures?

··· Before moving forward, a couple distinctions need to be made regarding the field of biomimicry. In the realm of architecture, there is often confusion between biomimetic design and biomorphic design. While both disciplines refer to nature as a source of inspiration, the reasons why they look to nature differ from each other. In contrast to the functional discipline of biomimicry, 18

12. Pawlyn, “Introduction.”

13. Ibid.

14. Ibid., “Chapter 1.”

15. Ibid.

BIOMIMCRY IN ARCHITECTURE

Fig. 7. Southern magnolia.

Fig. 8. Drawings showing the curve and fold of the Southern magnolia plant.

19

THEORETICAL FRAMEWORK

biomorphism strives to mimic the form and aesthetic of nature. To compare the two, it would be productive to look at Eero Saarinen’s biomorphic TWA terminal (Fig. 9) and Santiago Calatrava’s biomimetic Milwaukee Art Museum (Fig. 10 & 11). While both buildings look to birds for design inspiration, Saarinen’s TWA terminal merely mimics the form of the bird while Calatrava’s museum design features a mobile sunscreen that imitates the movement of bird wings.16 Analyzing this example, it can be said that biomorphism focuses on formal and aesthetic concerns while biomimicry searches for functional solutions for design challenges.

Furthermore, what is important to note about biomimicry is that what exists in nature should not serve as the limit to what we as humans can invent.

It is undeniable that we have already developed an abundance of technological achievements that prove to be more efficient than what exists in nature; however, Pawlyn argues that “biology has solved equivalent challenges with [a] greater economy of means.”17 To design biomimetically is to take advantage of human innovation while looking to nature to guide our goals of efficiency, resourcefulness, and adaptability.

Fig. 9. Eero Saarinen’s biomorphic TWA Terminal

16. Pawlyn, “Introduction.”

17. Ibid.

20

BIOMIMCRY IN ARCHITECTURE

Fig. 10. Santiago Calatrava’s biomimetic Milwaukee Art Museum

Fig. 11. Motion diagram of the Milwaukee Art Museum

··· Following the mindset and the axiom posed by Pawlyn, this thesis will explore the design of a deployable structure that mimics nature’s functions while striving for sustainability.

21

Sustainable Architecture

To make the connection between biomimicry and sustainability, it is productive to discuss first the concept of sustainable architecture. What makes something sustainable?

In definition, “sustainable” means: (adj): (1) Capable of being maintained or continued at a certain rate or level; (2) Designating forms of human activity (esp. of an economic nature) in which environmental degradation is minimized, esp. by avoiding the long-term depletion of natural resources.18 Sustainable architecture is then defined as: (n): Architecture managed in such a way as to employ design techniques which minimize environmental degradation and make use of low-impact materials and energy sources. 19 In the discourse of architecture, the concept of sustainability manifests in a variety of ways: some focus on developing tangible design strategies while others evaluate the relationship between a building and its context.

22

18. Oxford English Dictionary, “Sustainable.”

19. Ibid., “Sustainable architecture.”

To examine the idea of sustainable architecture, the arguments of Helen Bennets, Antony Radford, and Terry Williamson in their text Understanding Sustainable Architecture will be examined. These authors state that “sustainable architecture” is a “revised conceptualization of architecture in response to a myriad of contemporary concerns about the effects of human activity.”20 In this definition, there is no explicit discussion of the natural environment, as the authors believe that “sustainable” is just a label for a set of beliefs and attitudes that emerged in response to concerns that stem from human impact. Particularly, they quote Susan Maxman, the previous President of the American Institute of Architects:

“ Sustainable architecture isn’t a prescription. It’s an approach, an attitude. ” 21

For these authors, their approach to sustainable architecture involves the “triple bottom line,” which includes a building’s environmental, economic, and sociocultural context.22 Expanding upon the relationship between these three contexts, the building needs to participate in a “suitable building system model” that has five subsystems: the Environment, the Building, its Occupants, the Economy, and Society (Fig. 12).23

Fig. 12. Diagram included by Bennets et. al to visualize the five subsystems within the building system model

20. Bennetts et. al., Understanding Sustainable Architecture, 1.

21. Ibid., 7.

22. Ibid., 4.

23. Ibid., 85.

23

THEORETICAL FRAMEWORK

For the building system to work, it must deal with “the needs of all relevant stakeholders - human and non-human.”24 The needs referred to in this statement points to a cycle of inputs and outputs that form the rules of environmental sustainability:

“ Input rule: Inputs to a system must be constrained within the ability of the wider system to continue to provide the same inputs without degradation.

Output rule: Emissions from a system must be contained within the ability of the wider system to continue to assimilate them without degradation.25

”

Synthesizing these holistic theories posed by the authors, sustainable architecture needs to meet certain goals with the five subsystems noted above: Subsystem Environment

Goals Minimizing outward emissions and resource extractions. 26

Society

Transmitting knowledge and tradition in building design to remain socially and culturally relevant. 27

Occupants

Ensuring the well-being, health, and safety of building occupants. 28

Economy

Efficiently allocating resources to gain a net profit. 29

The Building

Accounting for building longevity by “balancing present requirements against the uncertainty of future possible requirements.” 30

24

24. Bennetts et. al., Understanding Sustainable Architecture, 85.

25. Bennetts et. al., Understanding Sustainable Architecture, 84.

26. Ibid., 86.

27. Ibid., 89.

28. Ibid., 91.

29. Ibid., 91-92.

30. Ibid., 93

SUSTAINABLE ARCHITECTURE

The building industry is aware of these goals and has devised rating systems and codes to govern sustainable design. Most popular today, the US Green Building Council’s LEED Green Building Rating System employs a point system to certify how “green” a building is. This system strives to “transform the way buildings and communities are designed, built, and operate;” however, in practice, green strategies are incorporated into building designs with little thought to the specificities of that building and its occupants.31 Additionally, the point system pushes aside genuine intentions of sustainability, encouraging point racking for a certain certification.

Such an issue is present in other rating systems, as most have been tainted with the rise of greenwashing practices. Emerging in the 20th century as a response to the environmental crisis, one method for practicing sustainability was to make greenness “marketable.”32 Sustainable architecture then became an economic race to produce and develop technologies and buildings that could be labelled as “environmentally friendly.” New technologies and building materials were then advertised as products that will make any building “green.”33 However, as the authors point out “the use of such materials and devices [i.e. high-tech gadgets and biodegradable materials] is not alone a sufficient indicator of an environmentally friendly building.

There must be demonstrable benefits in the particular case.”34 The authors of this text push back on official sustainable rating systems, arguing that an “attempt to accommodate real complexities of the world in neat regulations” will not lead to a sustainable architecture. Architects’ reliance on these rating systems is misconstrued, for these codified guidebooks fail to treat each building and its context as unique design challenges.35 Truly sustainable architecture changes and adapts to each new project, calling for a dedicated examination of all that the building relates to and impacts.

··· This thesis will approach the idea of sustainable architecture in a fashion that is (1) based on natural processes and (2) adapted specifically to the micro- and macro-climate of the thesis location.

31. “LEED rating system.”

32. Bennetts et. al., Understanding Sustainable Architecture, 10.

33. Ibid., 7.

34. Ibid., 11.

35. Ibid., 126.

25

26 6

II. SITE CONTEXT

Greenworks vision will help create a city where all “ Each Philadelphians enjoy benefits from sustainability...

Major Jim Kenney, Greenworks: Vision for a Sustainable Philadelphia

27

Site: Philadelphia, PA, USA

To site this design exploration, the city of Philadelphia was chosen for its unique characteristics regarding its climate, built environment, and declining urban tree canopy. However, to ensure a thorough analysis of the city, a climatic examination is done at three scales: (1) Pennsylvania as a whole (2) the city of Philadelphia (3) the City Hall area within the Center City neighborhood.

29

Climate Change in Pennsylvania

Starting in the mid-20th century, the dominant source of global warming became human activities. The past 40 years itself saw a steady increase in the planet's average surface temperature, contributing to the total surface temperature rise of 1.1°C since the late 19th century (Fig. 13).36 As the threat of global warming continues to worsen globally, projected climate changes in Pennsylvania indicate a need for action.

In a study conducted by the Climate System Research Center at the University of Massachusetts Amherst, a 2°C increase in global temperatures would cause: 1. Warmer summers and winters 2. An increase in days above 100° F in Philadelphia (Fig. 14) 3. More rain precipitation 4. Less snow precipitation 5. A rising sea level (Fig. 15 & 16) 6. An increase in storm surges and high tides 37 These projected changes will result in negative impacts on “human health, ecosystems, and the economy,” making it imperative for us to tackle the major cause of global warming: greenhouse gas (GHG) emissions.38 30

36. "Climate Change: How Do We Know?," NASA Global Climate Change.

37. Bradly et. al., “PA Climate Report and Projection,” 6-15.

38. Ibid., 7.

The global average temperature has already increased by about 1oC (1.8oF) relative to pre-industrial levels.

Warming relative to 1850-1900

Current CO2 emissionss are tracking the ‘higherr emissions’ scenario; unless emissions aree reduced, the 2oC threshold will bee crossed before 2050.

Higher Emissions 4.0-6.1oC High Emissions 2.6-3.7oC Lower Emissions 2.0-3.0oC

2015 Fig. 13. Climate System Research Center graphic revealing the global warming trends since 1950

31

SITE CONTEXT

Days over 90oF

Days over 100oF

Loweremissions Higher Lower

Emissions Fig. 14. Projected increase in days over 100° F

32

CLIMATE CHANGE IN PENNSYLVANIA

PROJECTIONS Sea level will continue to rise throughout this century

OBSERVATIONS

PROJECTIONS

Source: IPCC

Fig. 15. Projected sea level rise

Projected inundation around Philadelphia

Fig. 16. Projected flooding of Philadelphia due to sea level rise

33

Philadelphia, PA

The climate crisis is not a new development, and the city of Philadelphia has already made steps to create plans of sustainability. Most notably the Mayor’s Office of Sustainability has declared its commitment to the goal of “achieving an 80% reduction in emissions by the year 2050” in its report, Greenworks: A Vision for a Sustainable Philadelphia.39 This framework for sustainability focuses on the people of Philadelphia, striving to ensure every resident “is healthy, lives in a quality neighborhood, and has the opportunity to prosper.”40 More concretely, eight visions (Fig. 17.) addresses concerns in: 1. Food and water

5. Green spaces

2. Air

6. Transportation

3. Energy

7. Waste

4. Natural resources

8. Civic engagement41

With these sustainable visions, this report hopes to improve the equity, health, environment, and economy of the city. The report acknowledges that these goals are not something to be achieved overnight or even in a couple of years.42 Such long-term committment to the city, its communities, and climate change is admirable, serving as an example to be followed elsewhere.

34

39. Foti et. al. “Options for Achieving Deep Reductions in Carbon Emissions,” 3.

40. Kenney, Greenworks: A Vision for a Sustainable Philadelphia, 1.

41. Ibid., 4-5.

42. Ibid., 3.

V ISIO N 1

VI SI ON 2

All Philadelphians have access to healthy, affordable, and sustainable food and drinking water VIS ION 1

All Philadelphians breathe healthy air inside and outside VIS ION 1

V I SI ON 4

VISIO N 3

All Philadelphians are prepared for climate change and reduce carbon pollution

All Philadelphians efficiently use clean energy that they can afford VIS ION 1

VISIO N 5

VI SI ON 1

All Philadelphians benefit from parks, trees, stormwater management, and healthy waterways

V I SI ON 6

All Philadelphians have access to safe, affordable, and lowcarbon transportation

VI SI ON 1

VIS ION 1

VISIO N 7

V I SI ON 8

All Philadelphians waste less and keep our neighborhoods clean

All Philadelphians benefit from sustainability education, employment, and business opportunities

VIS ION 1

Fig. 17. The eight sustainable visions outlined by the Mayor's Office of Sustainability

35

SITE CONTEXT

Focusing on the outlined strategies for sustainability in the built environment, a report by the Drexel University expands on three routes of action: (1) retrofitting buildings, (2) exploring alternative transportation methods, and (3) decarbonizing electricity supplies 43

··· Like most urban metropolises, Philadelphia’s buildings contribute to a majority of the city’s GHG emissions - 79% of the city’s total GHG emissions to be exact.44 Most of Philadelphia building emissions come from its energy uses, as energy consumption accounts for 60% of the city’s total GHG emissions (Fig. 18).45 In looking for ways to improve the energy efficiency of Philadelphia’s buildings, retrofitting existing buildings proves to be more environmentally friendly. Doing so prevents the additional release of embodied energy, which accompanies new constructions. With the abundance of older buildings in the city, there is ample room for improvement using retrofitted technologies and structures.

Fig. 18. Data about the carbon emissions of Philadephia benchmarked buildings

43. Kenney, Greenworks: A Vision for a Sustainable Philadelphia, 3.

44. “Where do Philly’s Carbon emissions come from?”

45. Foti et. al. “Options for Achieving Deep Reductions in Carbon Emissions,” 3.

36

Case Studies in Center City

To begin tackling the inefficiency exhibited by the city’s buildings, the City of Philadelphia enacted the Building Energy Benchmarking Ordinance in 2012.

Through this program, the city requires all large commercial and multifamily buildings with an area of 50,000 square feet or more to report their annual energy and water usage.46 This benchmarking program gives the city a quantifiable metric to combat the issue of building GHG emissions, and its data is open to the public through the online benchmarking mapping tool.47

··· Zeroing in on a neighborhood to focus on, the city's bustling Center City was chosen for its high density of occupants, transportation, and infrastructure. Officially, this neighborhood spans from the Delaware River on the east to the Schuylkll River on the west and from Spring Garden Street in the north to South St in the south.47 Within this neighborhood, the area around City Hall was pinpointed for a deeper microclimatic study. Located at 1400 JFK Blvd, the historic City Hall attracts a multitude of visitors, both city-dwellers and tourists looking to begin their Philadephia explorations at its center. The consistent crowds of people plus the presence of tall buildings all around makes City Hall a prime location for a study on sustainable design that is beneficial to the environment and surrounding community.

46. The City of Philadelphia Building Energy Benchmarking.

47. "Philadelphia Building Energy Benchmarking Visualization Tool."

48. "Center City," Visit Philly.

37

SITE CONTEXT

Using the information available with the benchmarking program, two buildings in the City Hall area were chosen as case studies for this thesis:

1. Two Penn Center, 1500 JFK Blvd

Architect:

Vincent Kling

Year completed:

1958

Architectural style:

International Style

Height:

271 feet (20 floors)

Facade materials:

Aluminum window frames with glazing and limestone spandrels

Benchmarking data: GHG:

2,948 MtCo2e

Electricity usages:

24,705,132 Btu

Energy star rating:

6849

49. “Philadelphia Building Energy Benchmarking Visualization Tool.”

38

CASE STUDIES IN CENTER CITY

2. Ritz Carlton Hotel, 10 Ave of the Arts McKim, Mead & White

Architect: Year completed:

original bank completed in 1931; renovated into a hotel in 2000

Architectural style:

Neoclassical

Height:

393.3 feet (30 floors)

Facade materials:

Punch windows with steel frame structure and marble cladding

Benchmarking data: GHG:

3,633 MtCo2e

Electricity usages:

19,724,724 Btu

Energy star rating:

1350

50. “Philadelphia Building Energy Benchmarking Visualization Tool.”

39

SITE CONTEXT

The combination of these two buildings allow for the testing of my design idea on different building programs, façade types, and energy star ratings. These two buildings were chosen also for their proximity to the city hub of Center City. The surrounding area of these two buildings experience a substantial amount of vehicular and pedestrian traffic (Fig. 19 & 20), correlating with a higher CO2 emission content in the area (Fig. 21). Delving further into the specificities of each building, a solar analysis on the buildings’ elevations revealed a clear favoring of sunlight exposure on the south and east elevations (Fig 22-24). Interestingly, there were moments of intense sun exposure on the upper portions of the north and west façades. With such direct sunlight hitting the buildings at certain areas, one fruitful path for improving energy efficiency is to provide sun breakers. By reducing the heat gain that accompanies the penetration of sunlight into the building interior, less energy would need to be consumed for cooling the building.

40

LO VE PA RK

N. BR O AD

N. 15 TH ST

N. 16 TH ST

ST

CASE STUDIES IN CENTER CITY

AR CH ST Y BL VD

N. 13 TH ST

JO HN F KE NN ED

TW O PE NN CE NT ER

D IL W O R TH

ST

SA NS OM

UT ST

FI LB ER T

ST

M AR KE T

ST

C IT Y H A LL

S. BR OA D CH ES TN

Y BL VD

PARK

N. 15 TH ST

M AR KE T

JO HN F KE NN ED

GI RA RD PA RK

ST

RI TZ CA RL TO N HO TE L

ST

TRAFFIC FLOW

S. 13 TH ST

S. BR O AD ST

N

S. 15 TH ST

S. 16 TH ST

CH ES TN

UT ST

SA NS OM

ST

Fig 19. Plan analysis of Center City: The Center City neighborhood features numerous transit stops - both above ground and below ground. The collection of "green" spaces around City Hall also attracts more visitors.

BUS/TROLLEY STOPS

UNDERGROUND TRANSIT STATIONS

PARKS/OUTDOOR SPACES

41

LO VE PA RK

N. BR OA D ST

N. 15 TH ST

N. 16 TH ST

SITE CONTEXT

AR CH ST Y BL VD

N. 13 TH ST

JO HN F KE NN ED

TW O PE NN CE NT ER

DI LW O RT

ST

Y BL VD FI LB ER T

ST

MA RK ET

ST

H PA RK

N. 15 TH ST

MA RK ET

JO HN F KE NN ED

CI TY HA LL

S. BR OA D ST CH ES TN

UT ST

GIR AR D PA RK

RI TZ CA RL TO N HO TE L

LIGHT TRAFFIC

SA NS OM

ST

Fig. 20. Vehicular traffic analysis

42

S. 13 TH ST

ST S. BR OA D

N

S. 15 TH ST

HEAVY TRAFFIC

S. 16 TH ST

CH ES TN

UT ST

SA NS OM

ST

LO VE PA RK

N. BR OA D

N. 15 TH ST

N. 16 TH ST

ST

CASE STUDIES IN CENTER CITY

AR CH ST Y BL VD

N. 13 TH ST

JO HN F KE NN ED

TW O PE NN CE NT ER

DI LW O RT

ST

Y BL VD FI LB ER T

ST

MA RK ET

ST

H PA RK

N. 15 TH ST

MA RK ET

JO HN F KE NN ED

CI TY HA LL

S. BR OA D ST CH ES TN

UT ST

GIR AR D PA RK

RI TZ CA RL TO N HO TE L

LOW CO 2 EMISSIONS

SA NS OM

ST

S. 13 TH ST

S. BR OA D ST

N

S. 15 TH ST

HIGH CO 2 EMISSIONS

S. 16 TH ST

CH ES TN

UT ST

SA NS OM

ST

Fig. 21. CO2 emissions analysis by streets: The area around the two case study buildings experience heavy vehicular traffic congestion, resulting in a higher concentration of CO2 emissions in those areas.

43

SITE CONTEXT

Beginning zones of exposure on the Summer Solstice

BEGINNING ZONES OF EXPOSURE

WEST ELEVATION

NORTH ELEVATION

SOUTH ELEVATION

EAST ELEVATION

NORTH ELEVATION

SOUTH ELEVATION

EAST ELEVATION

TWO PENN CENTER 4:30 AM

SUMMER SOLSTICE JUNE 21, 2021 SUNRISE: 3:44 AM SUNSET: 8:55 PM

S

W

E

N

RITZ CARLTON HOTEL 4:30 AM

Peak zones of exposure on the Summer Solstice

PEAK EXPOSURE

WEST ELEVATION TWO PENN CENTER 10:00 AM

SUMMER SOLSTICE JUNE 21, 2021 SUNRISE: 3:44 AM SUNSET: 8:55 PM

44

S

W

E

N

RITZ CARLTON HOTEL 12:00 PM

CASE STUDIES IN CENTER CITY

Ending zones of exposure on the Summer Solstice WEST ELEVATION

NORTH ELEVATION

SOUTH ELEVATION

EAST ELEVATION

TWO PENN CENTER 6:30 PM

SUMMER SOLSTICE JUNE 21, 2021 SUNRISE: 3:44 AM SUNSET: 8:55 PM

S

W

E

N

RITZ CARLTON HOTEL 6:30 PM

Fig. 22. Sun/shade analysis on the Summer Solstice

45

SITE CONTEXT

Fig. 23. Overlay of beginning, peak, ending zones of exposure for each month

46

CASE STUDIES IN CENTER CITY

47

SITE CONTEXT

Fig. 24. Overlay of sun exposure zones: In evaluating the overlay of the 12 months, it is found that the sun favors the southern and eastern elevations. Occasionally, the northern and western elevation corners get a decent amount of exposure.

48

CASE STUDIES IN CENTER CITY

49

Urban Heat Islands & Street Trees

Another aspect to consider about the city of Philadelphia is the challenges it faces as a dense urban center. The condensing of row houses and buildings into paved city grids results in a loss of street trees and tree coverage. With less trees, more buildings, and more exposed asphalt, the urban heat island effect becomes apparent.51 From this effect, an urban area can experience a temperature increase as high as 20°F compared to more vegetated areas.52 The drastic increase in local temperature of an urban region can be detrimental to human well-being and also result in a reliance on more energy for cooling purposes.53 More energy consumption for cooling thus results in increased production of GHG emissions and other air pollutants.

··· As the climate crisis gradually raises the overall temperature of Philadelphia, the heat island effect is becoming a point of increasing concern.

Based on a spatial analysis of Philadelphia's urban heat islands (Fig. 25), there are concentrated regions with a surface temperature that reaches 95°F or higher. The area around City Hall reveals a surface temperature around 90°F (Fig. 26).54 Thinking about the many visitors that filter through this area year-round, the challenge of heat mitigation arises to ensure the comfort and well-being of the area’s occupants.

50

51. “Understand Urban Heat Islands.”

NIHHIS. 52. Ibid.

53. Ibid.

54. Steif, “Urban heat islands & street trees in Philadelphia.”

Fig. 25. Mapping of average surface temperature across Philadelphia

Fig. 26. Close up on the Philadelphia surface temperature map with City Hall outlined

51

SITE CONTEXT

)\MWXMRK 8VII 'ERST] >MT 'SHIW

8VII 'ERST] 'LERKI >MT 'SHIW

52

Fig. 27. Percentage of existing tree canopy by zip code in Philadelphia; the City Hall area is denoted by the zip code 19107

Fig. 28. Percentage of tree canopy change by zip code in Philadelphia; the City Hall area is denoted by the zip code 19107

URBAN HEATH ISLANDS

& STREET TREES

The worsening heat islands in Philadelphia is exacerbated by a diminishing urban tree canopy. According to the 2019 Philadelphia Tree Canopy Assessment, the city has experienced a 6% loss in tree canopy over the past decade. To put that value into perspective, the report estimated that the 6% lost is equivalent to over 1,000 football fields worth.55 While in the past street trees were for aesthetic purposes of beautification, they have evolved to play important roles in not only mitigating the urban heat island effect, but also sequestering atmospheric CO2 and intercepting rainfall. Outside of environmental impacts, street trees also provide social and economic benefits, with some studies revealing that they “[improve] human health, [reduce] crime, [increase] community interaction, and [boost] property values.”56 Adding a bit of green to the city will not only increase the liveability of that city, but also the health of its occupants. By reducing the number of trees within an area of the city, that region incurs numerous losses. In light of the current climate crisis, the most detrimental effect of less street trees would be a diminished capacity to capture CO2 and moderate the radiation of heat from surrounding streets and buildings.

··· Focusing on the heavily urbanized area around City Hall, this bustling city neighborhood has a tree canopy coverage of roughly less than 8% (Fig. 27).57 In the past decade, this area has lost about 8% of its past tree canopy, as trees are cleared for more infrastructure (Fig. 28).58 The dense collection of buildings and transit stops in this neighborhood makes it difficult to plant street trees or incorporate other types of greenery. These trends are alarming, particularly for an area as active and susceptible to the heat island effect as the City Hall neighborhood. Though a few street trees exist around the case study buildings, the area can benefit from more greenery.

55. O’Neil-Dunne, Tree Canopy Assessment, Philadelphia, PA, 5.

56. Beecham & Lucke, “Street Trees in Paved Urban Environments,” 21.

57. O’Neil-Dunne, Tree Canopy Assessment, 9.

58. Ibid.

53

Macro/Microclimatic Challenges

Synthesizing the climatic analyses of Pennsylvania and Philadephia's macroclimate and City Hall's microclimate, three challenges arise that require additional attention and novel design solutions: 1. Solar shading 2. CO2 capture 3. Urban heat island effect Philadelphia's current sustainability plans are admirable; however, the alarming exacerbation of climate change and global warming during recent years calls for an intensified effort from all sectors to save our environment.

Particularly, the architecture and building industries must use their creative thinking to innovate sustainable and regenerative design solutions.

··· With these challenges in mind, an inquiry into how nature solves these problems produces a simple answer: plants. As one of Earth’s first inhabitants, plants hold many secrets and time-tested strategies that will help us navigate the challenges of an urban city like Philadelphia.

54

Morris Arboretum, Philadelphia, PA

55

56 56

III. BIOMIMETIC STUDIES

ne challenges in functional terms and then see how “ Defi that function is delivered in biology.

Michael Pawlyn, Biomimicry in Architecture.

57

CO2 Capture - Plant Leaves

To begin my biomimetic study of plants, I looked at the basic process of survival for all green plants: photosynthesis. This biological process occurs in the leaves of plants, allowing plants to take in water, CO2 and sunlight from its environment in order to produce oxygen and sugars (Fig. 27). Through this process, CO2 is naturally captured from the atmosphere and is converted into a fuel source for the plant.59

Fig. 29. Diagram of photosynthesis process in a leaf

SUN LIGHT ENERGY

O2

RELEASED INTO ATMOSPHERE

PHOTOSYNTHESIS: H 2 O + CO 2 O 2 + SUGARS H 2O

THROUGH ROOT/STEM/ VEINS

SUGARS TRAVEL TO REST OF PLANT AS FOOD

CO 2 THROUGH

LEAF STOMA

59. Lambers, “Photosynthesis.”

59

BIOMIMETIC STUDIES

An inquiry into the possibility of artificial photosynthesis led to the discovery of a study done by the Reisner Lab at the University of Cambridge. In this innovative study, the team, led by Researcher Qian Wang, was able to develop a device that uses photocatalyst sheets to mimic photosynthesis (Fig. 30 & 31). By vacuum-evaporating photocatalyst particles onto a gold layer, the research team was able to create a device that can take in CO2, water, and sunlight to produce formic acid - a usable liquid fuel (Fig. 32).60 The device is still in its developmental stages and currently only works in a laboratory setting where the photocatalyst device is submerged in a chemical solution; however, the researchers are confident that the device will be able to function using water vapor and atmospheric CO2 in the future (Fig. 33 & 34).

The resultant formic acid of the artificial leaf can be transported to a formic acid fuel cell, creating a 100% efficient cycle of resources that not only reduces the CO2 content of the surrounding atmosphere, but also provides a clean, solar fuel source. The formic fuel cell, the recently developed cell by the GRT Group does not require a connection to power grids, and thus, poses as an alternative, flexible fuel source that can supplement existing electricity infrastructures (Fig. 35). The fuel cell works by converting formic acid into hydrogen gas, which is already used as a clean source of electricity (Fig. 36).61 In incorporating these two technologies into this thesis exploration, the issue of high carbon dioxide emissions in the City Hall area will be adequately addressed.

60. Wang et. al., “Molecularly engineered photocatalyst sheet.”

61. “Team creates world’s first formic acid-based fuel cell,” Ecole Polytechnique.

60

CO2 CAPTURE

Fig. 30. Comparison between photosynthesis on a leaf an artificial photosynthesis

SUN LIGHT ENERGY

O2

RELEASED INTO ATMOSPHERE

PHOTOSYNTHESIS: H 2 O + CO 2 O 2 + SUGARS H 2O

THROUGH ROOT/STEM/ VEINS

SUGARS TRAVEL TO REST OF PLANT AS FOOD

CO 2 THROUGH

LEAF STOMA

SUN

H 2O SUBMERGED IN AQUEOUS SOLUTION WITH H 20 AND CO 2 CO 2

ARTIFICIAL PHOTOSYNTHESIS OCCURRING ON PHOTOCATALYST SHEETS ON GLASS SUBSTRATE H 2 O + CO 2 1/2O 2 + HCOO - + H +

O2

HCOO -

OXYGEN

FORMATE

Fig. 31. Photo of researcher Qian Wang holding the photocatalyst sheet that is on a glass substrate

61

BIOMIMETIC STUDIES

SUN

H 2O SUBMERGED IN AQUEOUS SOLUTION WITH H 20 AND CO 2

ARTIFICIAL PHOTOSYNTHESIS OCCURRING ON PHOTOCATALYST SHEETS ON GLASS SUBSTRATE H 2 O + CO 2 1/2O 2 + HCOO - + H +

O2

HCOO -

CO 2

OXYGEN

FORMATE

20 cm 2

GOLD LAYER - FOR ELECTRON TRANSFER

PHOTOCATALYST A

RuO 2-BiVo 4:Mo

- oxides water to supply electrons and H +

PHOTOCATALYST B CotypP-SrTiO 3:La,Rh

- catalyzes CO 2 & reduces it to formate (HCOO -)

SHEET CREATED BY MIXING THE TWO PARTICLE POWDERS AND PRODUCING A MEDIUM THAT IS THEN VACUUM EVAPORATED

Fig. 32. Diagram explaining how the photocatalyst sheets work to photosynthesize

62

CO2 CAPTURE

1 cm

CO 2-SATURATED AQUEOUS SOLUTION OF KHCO 3 - provides the CO 2 & H 2O needed for the reactions to occur - in future, atmospheric CO 2 can be used if water vapor is substituted for liquid H 2O

NOT TO SCALE

GLASS SUBSTRATE - 0.5 cm CARBON TAPE - 0.2 cm GOLD LAYER - ~300 nm PARTICLE LAYER - ~10 m

O2 HCOO

-

O2 H+

O2

FORMIC ACID

REACTION SOLUTION = LIQUID FORMIC ACID - products of HCOO - and H + within the solution creates the liquid formic acid - solution can be used in fuel cell H+ HCOO -

NOT TO SCALE

EXTERNAL FORMIC ACID FUEL CELL

63

BIOMIMETIC STUDIES

RESERVOIR OF COLLECTED WATER

SUN WATER RUNS DOWN THE SRF OF THE SHEET

ATMOSPHERIC CO 2

CO 2 O2 O2

REACTION SOLUTION = LIQUID FORMIC ACID

H+ HCOO

-

FORMIC ACID

EXTERNAL FORMIC ACID FUEL CELL

Fig. 33. Potential application outside of the laboratory using running water

64

CO2 CAPTURE

RESERVOIR OF COLLECTED WATER

SUN VAPORIZING THE HE WATER R TO CREATE CLOSED LOSE SYSTEM M WITH WATER VAPOR POR

ATMOSPHERIC CO 2

CO 2

O2 O2

REACTION SOLUTION = LIQUID FORMIC ACID

H+ HCOO

-

FORMIC ACID

EXTERNAL FORMIC ACID FUEL CELL

Fig. 34. Potential application outside of the laboratory using water vapor

65

BIOMIMETIC STUDIES

Fig. 35. Stand-alone formic acid fuel cell produced by Swiss team GRT Group

Fig. 36. Diagram explaining the process of using formic acid as a fuel

66

Heat Island Mitigation - Forest Canopy

Moving forward to think about the issue of the urban heat island, the world of plants reveals inspiring solutions in the forest canopy. In a forest, the canopy structure is made up of the various tree crowns (the upper portion of the tree that contains the branches, leaves, flowers, and fruits).62 The dense overlay of different tree crowns in a forest makes the canopy a key player in sustaining the forest ecology. The functions of the forest canopy include: 1. Capturing light for photosynthesis 2. Providing shade from the sun 3. Moderating the temperature of the forest interior 4. Acting as windbreaks and intercepting rainfall 5. Creating niches for animals, birds, and insects to occupy 63 This thesis will focus on the forest canopy’s ability to provide shade with its high surface area of leaves and its ability to moderate temperature and rainfall. During rainfall, rainwater is either captured on the leaves of the canopy or absorbed into the roots. With sunlight, the intercepted water on the leaves evaporates while the water within the root system travels up the tree and transpires into the atmosphere as water vapor (Fig. 37). The 64

combination of these two processes, called evapotranspiration, not only

62. Trimble,“The Forest Canopy: Structure, Roles & Measurement.”

63. Ibid.

64, “Stormwater Benefits of Trees.”

67

BIOMIMETIC STUDIES

prevents water from becoming runoff, but it also cools the surrounding area.

Totaling the cooling effect of all the trees that make up a forest canopy, the forest environment becomes one that is incredibly cool and moderate.

To translate this canopy function into the built environment to cool the urban heat island, Nikken Sekkei’s Sony Osaki Building serves as an excellent precedent to study (Fig. 38). This innovative building in Japan features a facade system called BioSkin, which consists of porous ceramic pipes that evaporate water and cools the building surface up to 12°C (Fig. 39 & 40).

The ceramic tubes that span the building elevations were able to collectively change the building’s surrounding micro-climate by 2°C (Fig. 41).65 Looking at this built strategy, a biomimetic approach to reducing the heat island effect would be to replicate the evaporation of water on a building’s surface.

65. Galloway, “Building Skin Developed That Could Cool Our Cities.”

68

HEAT ISLAND MITIGATION

PRECIPITATION

RAIN RAINWATER R NW WATER R INTERCEPTED IN NTE ERC TED ER ERCEPTE LEAVES

BY LE LEA AVES EVAPORATES EVAP APORAT

WATER FFROM ROO OOTS S ROOTS TTRANSPIRE TRA ANSPI SPIRE R FFROM FRO O M LEAVES OM LLE EAVE

RAINWATER IN THE GROUND ABSORBED BY ROOTS

Fig. 37. Process of evapotranspiration

69

BIOMIMETIC STUDIES

Fig. 38. Nikken Sekkei’s Sony Osaki Building in Japan

Fig. 39. BioSkin system, which consists of porous ceramic tubes on the building's facade

70

HEAT ISLAND MITIGATION

Fig. 40. Section of the ceramic porous tubes

Fig. 41. Infrared images showing the cooling effect of the BioSkin

71

Solar Shading - Spanish Moss

To address the final concern of solar shading, the Spanish moss provides an interesting strategy of adaptation and responsivity. As an epiphyte, this plant is unrooted and grows on the surface of other plants. What makes this plant unique is its ability to respond to sunlight based on its own water content with its covering of scaly hairs on its stems (Fig. 42 & 43). These hairs absorb nutrients and water while also capturing air pollutants.66 When the moss does not have enough water to photosynthesize, the scaly hairs stand up, changing the moss’s appearance to a pale, gray color. With this configuration, the scales reflect the sunlight away from the planting, reducing any additional dehydration.

On the other hand, when the plant has an adequate amount of water in it, the scales lie flat against the stem, turning the moss back to its green color.

As a result of the scales lying flat, the plant is able to more readily absorb solar energy to power its processes of photosynthesis.

The movement of these scales rely on the turgor pressure caused by the intake of water into the plant cells - with enough water, the cells of the scale become turgid and allow for the scales to lie flat (Fig. 44).67 This adaptation to control sunlight absorption is fascinating and will inform the responsivity of this thesis design to the atmosphere’s solar and water content.

72

66. Garth, "The Ecology of Spanish Moss (Tillandsia Usneoides): Its Growth and Distribution," 470.

67. Billings, “A Study of Tillandsia usneoides,” 115.

Fig. 42. Hanging Spanish moss

Fig. 43. Scaly hairs on the stems of the Spanish moss

73

BIOMIMETIC STUDIES

Fig. 44. Difference between the wet and dry scales of the Spanish moss

74

SOLAR SHADING

In summary of the plant strategies extracted from a biomimetic approach to solving Philadelphia’s urban challenges:

Plant leaves - photosynthesis

Forest canopy - evaporative cooling

Spanish moss - adaptive shading in response to surroundings 75

76

IV. DESIGN

start with reality: always start by identifying the “ Never ideal and then compromise as little as necessary."

Michael Pawlyn, Biomimicry in Architecture.

77

A Preliminary Design

As I begin to apply my biomimetic studies to designs, it is useful to remind myself of Pawlyn’s axiom of less materials, more shape, greater responsiveness.68 To re-create the urban tree canopy for Philadelphia, the process began with the smallest yet mightiest module within the forest canopy: the leaf.

Taking inspiration from the geometry of the Spanish moss scale (Fig. 45), a leaf-like modular panel was developed to apply the technology of artificial photosynthesis (Fig. 46 & 47). Three configurations were devised for this

SH MO SS

module, as it would respond to the atmosphere’s humidity and the presence of precipitation (Fig. 48).

Fig. 45. One scale of the Spanish moss

68. Pawlyn, “Chapter 1."

79

DESIGN

Fig. 46. Extraction of geometries from the Spanish moss scale

80

A PRELIMINARY DESIGN

d1

d2

a

d1 = width of fastener d2 = minimum 2×(d1)

a x

x/k

x = distance from axis line to edge x/k = a proportionally smaller distance where k is a constant based on distance from fastener

Fig. 47. Study of how the scale tilts and curves as it dries

81

DESIGN

LOW HUMIDITY

HIGH HUMIDITY

WATER VAPOR SUPPLIED BY TUBES

DEW DROPLETS FORMED BY

TUBES THAT SUPPLY WATER

VAPORIZERS

PHOTOSYNTHETIC SHEET PRINTED ON METAL

TUBES THAT COLLECT FORMIC ACID AND BRING TO FUEL CELL

Fig. 48. Three configuration of leaf-like module in response to low humidity, high humidity, and precipitation

82

A PRELIMINARY DESIGN

PRECIPITATION

Y COOLING THE METAL

GUIDES RAINWATER FOR COLLECTION

PANEL TILTED TO ALLOW RAINWATER TO FLOW DOWN TUBES THAT COLLECT FORMIC ACID AND BRING TO FUEL CELL TUBES THAT COLLECT WATER PHOTOSYNTHETIC SHEET PRINTED ON METAL

83

Re-assessment in Approach

Upon further analysis of the preliminary design, the literal interpretation of the leaf hindered the way for creative explorations of an efficient, deployable structure. Consulting nature again, the structural solution came in the form of the Hornbeam leaf and the Convolvulus genus of flowers.

The Hornbeam leaf has a pattern of alternating crest and valley folds to create a surface that is compact enough to withstand wind forces, but also rigid enough to support a maximum leaf surface area for photosynthesis (Fig. 49).69 On the other hand, introduced in Biomimicry in Architecture, the flowers within the Convolvulus genus twists from a compact bud into a fully extended flower (Fig. 51).70 Looking specifically at the Convolvulus cneorum, or more commonly known as the Silverbush, the pink twisted flower bud unfurls into a trumpet-shaped white flower everyday in the morning and then twists back at night (Fig. 52 & 53).71

··· What is similar with these two plants is their ability to respond to environmental conditions in predictable ways. Such predictability in movement can be mirrored in the built environment through the incorporation of origami tessellations.

84

69. Ralevski, “Folding Improves Flexibility and Rigidity.”

70. Pawlyn, “Chapter 1.”

71. “Convolvulus cneorum.

The Hornbeam leaf folding pattern is mimicked with the Miura-Ori tessellation pattern (Fig. 50).72

Mountain fold Valley fold

Fig. 49. The Hornbeam leaf and its pattern of alternating crest and valley folds

Mountain fold Valley fold

Fig. 50. The Miura Ori fold with similar alternating crest and valley folds 72. “The Miura-Ori Fold.”

85

DESIGN

Fig. 51. The twisted compact bud and unfurled shape

Fig. 52. Twisted pink bud of the Silverbush

Fig. 53. Open white flower of the Silverbush

73. Gjerde, “Ron Resche patent.”

86

RE-ASSESSMENT IN APPROACH

The twisting of the Convolvulus cneorum is similar to the twisting involved within Ron Resch’s square waterbomb pattern (Fig. 54).73

Fig. 54. Ron Resch square waterbomb tessellation

87

Modular Origami Tessellations

Moving forward, both nature-derived origami tessellation patterns were studied to produce a greater scope and range to test the design of an artificial urban tree canopy. These origami forms are conducive to the standards of fabrication, as all fabricated pieces can be made with flat sheets and hinges or joints to facilitate the folding action.

Having established the form of the modular pieces for this re-creation of the urban tree canopy, the next step is to use these components to address the three climatic challenges outlined previously. The many panels of both the Mirua-Ori and Ron Resch pattern offers the opportunity to assign various functions to each panel. Specifically, each panel would have one of four functions: 1. Artificially photosynthesize 2. Undergo evaporative cooling 3. Reflect sunlight 4. Provide structure for the conduits that supply water or collect formic acid Three configurations were developed to accommodate a range of climate conditions that affect temperature and natural photosynthesis (Fig. 55).

88

Using the Ron Resch waterbomb pattern, two different modules were formulated where one is the inverted version of the other. The normal orientation of the Evaporative Module (E-module) provides sufficient surface area to include all three functions of photosynthesis, cooling, and sunlight reflection into one module (Fig. 56 & 57). As such, this module will be best suited for areas that have a higher heat index, as they would require a greater mitigation of the heat islands through evaporative cooling.

On the other hand, the inverted orientation of the Carbon Module (C-Module) forms a configuration that is focused on carbon capture, for the protruding triangular panels are divided into photosynthesizing panels and reflective ones (Fig. 59 & 60) The motion of how these two modules twist were studied to create a track that facilitates their folding movement around the central panel (Fig. 58 & 61). In terms of how to control the folding action, the mechanics of an umbrella were studied to conceptualize a potential folding apparatus (Fig. 62). As a final exploration of this twisting module, the square panels of the tessellation pattern can be perforated to introduce various patterns and reduce material weight (Fig. 63 & 64).

EVAPORATIVE MODULE

CARBON MODULE

LINEAR MODULE

Fig. 55. Three modular configurations based on origami tessellation patterns

89

DESIGN

Fig. 56. Diagram of the Evaporative Module and when it is used

PHOTOSYNTHESIS PANEL

FORMIC ACID COLLECTOR

REFLECTIVE PANEL EVAPORATIVE PANEL WATER PANEL

MOVEMENT TRACK WATER SOURCE

CONFIGURATION FOR:

AREAS OF HIGH TEMPERATURES TIMES WHEN PLANTS ARE NATURALLY PHOTOSYNTHESIZING

90

NEED EVAPORATIVE FUNCTION LESS NEED FOR PHOTOSYNTHESIS FUNCTION

MODULAR ORIGAMI TESSELLATIONS

1 WATER SUPPLIED FROM SQUARES

2 SUNLIGHT REFLECTED TO REACH PHOTOSYNTHETIC PANELS

3 FORMIC ACID COLLECTED AT VALLEY NODE

4 WATER IS EVAPORATED FROM HEATED PANELS OR POROUS TUBES Fig. 57. Diagram of how the E-module works

91

DESIGN

1

2

5

6

Fig. 58. Diagram tracking the folding movement of the E-module

92

MODULAR ORIGAMI TESSELLATIONS

3

4

7

8

93

DESIGN

Fig. 59. Diagram of the Carbon Module and when it is used

REFLECTIVE PANEL

WATER SOURCE PHOTOSYNTHESIS PANEL

FORMIC ACID COLLECTOR

CONFIGURATION FOR:

AREAS OF COOLER TEMPERATURES TIMES WHEN PLANTS ARE NOT NATURALLY PHOTOSYNTHESIZING

94

NO NEED TO COOL BUILDING MORE NEED FOR PHOTOSYNTHESIS FUNCTION

MODULAR ORIGAMI TESSELLATIONS

1 WATER SUPPLIED FROM NODES AT THE PEAK

2 SUNLIGHT REFLECTED TO REACH PHOTOSYNTHETIC PANELS

3 FORMIC ACID PRODUCED ON PANELS COLLECTED IN PIPES

Fig. 60. Diagram of how the C-module works

95

DESIGN

1

2

5

6

Fig. 61. Diagram tracking the folding movement of the C-module

96

MODULAR ORIGAMI TESSELLATIONS

3

4

7

8

97

DESIGN

Fig. 62. Diagram showing a folding apparatus to support the movement of the E-module

98

MODULAR ORIGAMI TESSELLATIONS

99

DESIGN

Fig. 63. Form experimentation for the E-module using physical models made from Bristol and MDF

100

MODULAR ORIGAMI TESSELLATIONS

Fig. 64. Form experimentation for the C-module using physical models made from Bristol and MDF

101

DESIGN

In contrast the more organic system of the E- and C-modules, the Miura-Ori fold was utilized to create a more linear and simple design (Fig. 65 & 66). Containing all of the functions in this Linear Module (L-module), this configuration goes from an open flat sheet to a compact, accordion-fold component (Fig. 67), mimicking the Hornbeam leaf. Because this module contains all functions, it is adaptable for any weather condition.

Fig. 65. Diagram of the Linear Module and when it is used

EVAPORATIVE PANEL

WATER SOURCE

WATER SOURCE

WATER PANEL

PHOTOSYNTHESIS PANEL REFLECTIVE PANEL

CONFIGURATION FOR:

ANY TEMPERATURE RANGE ANY TIME DURING THE YEAR

102

HAS BOTH FUNCTIONS OF PHOTOSYNTHESIS AND EVAPORATIVE COOLING

MODULAR ORIGAMI TESSELLATIONS

1 WATER SUPPLIED FROM PIPES OF SUPPORT

2 SUNLIGHT REFLECTED TO REACH

PHOTOSYNTHETIC PANELS

3 FORMIC ACID COLLECTED AT VALLEY

NODE

4 WATER IS EVAPORATED FROM HEATED PANELS OR THROUGH POROUS TUBES Fig. 66. Diagram of how the L-module works

103

DESIGN

1

4 Fig. 67. Diagram tracking the folding movement of the L-module

104

2

5

MODULAR ORIGAMI TESSELLATIONS

3

6

105

DESIGN

Finally, to explore the arrangement of the three modules, the E- and C-modules were deployed on the Ritz Carlton south façade (Fig. 68) while the L-module was deployed on the south façade of the Two Penn Center (Fig. 73). With both deployments, an example of how the modules adapt to solar exposure on the facade is shown (Fig. 69-72; 74-77).

Fig. 68. Fully opened E- and C-modules on the Ritz south façade

106

MODULAR ORIGAMI TESSELLATIONS

Fig. 69. Adaptive modules on the Ritz south façade

Fig. 70. Adaptive modules corresponding to sun exposure

107

DESIGN

Fig. 71. Close-up of the adaptive E- and C-modules on the Ritz south façade

108

MODULAR ORIGAMI TESSELLATIONS

OPEN MODULE W/ LESS SUNLIGHT

CLOSED MODULE W/ MORE SUNLIGHT

Fig. 72. Close-up of the adaptive E- and C-modules corresponding to sun exposure

109

DESIGN

Fig. 73. Fully opened L-modules on the Two Penn Center south façade

110

Fig. 74. Adaptive L-modules on the Two Pen

nn Center south façade

MODULAR ORIGAMI TESSELLATIONS

Fig. 75. Adaptive modules corresponding to sun exposure

111

DESIGN

Fig. 76. Close-up of the adaptive L-modules on the Two Penn Center south façade

112

MODULAR ORIGAMI TESSELLATIONS

Fig. 77. Close-up of the adaptive L-modules corresponding to sun exposure

113

114 114

V. SYNTHESIS & REFLECTION

much sustainable design has been based on “ While mitigating negatives, biomimicry points the way to a new paradigm based on optimising positives and delivering regenerative solutions.

Michael Pawlyn, Biomimicry in Architecture.

115

Evaluation of Design Against Contextual Frameworks

To conclude this design exploration, the final modular designs will be evaluated with a synthesis of the initial theoretical framework, site analysis, and biomimetic studies. With this evaluation, I hope to reflect upon these three questions: 1. Do these designs appropriately mimic natural strategies to solve design challenges?

2. Do the designs address challenges that are specific to the macro and micro environment of Philadelphia?

3. Are the designs informed by Pawlyn’s principles of biomimicry in architecture and the approaches of sustainable architecture?

117

SYNTHESIS

& REFLECTION

1. Do these designs appropriately mimic natural strategies to solve design challenges?

With regards to the biomimetic studies, the plant strategies studied are apparent in the functionality of the final design; however, the difficulty with adhering to principles of biomimicry comes into play when thinking about fabrication and materiality. While the final modules take inspiration from physical strategies - like folding and twisting - and chemical strategies - like photosynthesis and evapotranspiration - the act of folding plate materials is a concept that is wholly man-made. The use of origami tessellations as the design form for these modules makes these designs inherently “unnatural.” In thinking about how this design can progress, an inquiry into how nature is pieced together structurally will be productive. Rather than basing the design off of the fabrication industry’s standard of sheet goods, is there a way to create something that is structured like nature but still constructible?

··· 2. Do the designs address challenges that are specific to the macro and micro environment of Philadelphia?

The narrowing of scope in the site analysis from Pennsylvania to Philadelphia to City Hall introduced a number of climatic challenges that would affect an individual sitting in an office chair within the Two Penn Center. With the functions built into the modules, a building retrofitted with them would be able to reduce the carbon emissions around it as well as minimize its contribution to the heat island effect. However, it is important to note that module density is a major factor to consider when evaluating whether or not these modules will have a beneficial effect on climatic conditions. On a building, an array of modules is needed to sufficiently capture CO2 or cool the building surface. Additionally, at the city-scale, more than one or two buildings need to be retrofitted with these modules in order to create any difference within the city atmosphere. Because of the 118

EVALUATION OF DESIGN

more micro-focused nature of these modules, a potential point of exploration is thinking about how these modules can be expanded or re-configured to address larger climate issues. With this point, there is a need to also think about efficiency and economic sustainability. Would the mass repetition of these small modules be the most resource-efficient way to fulfill the functions of artificial photosynthesis and evaporative cooling?

··· 3. Are the designs informed by Pawlyn’s principles of biomimicry in architecture and the approaches of sustainable architecture?

Finally, in the matter of sustainable architecture and Pawlyn’s principles, these modules have just scratched the surface of what it takes to make a design sustainable. Though the modules theoretically will have environmentally sustainable functions, there is much to explore with regards to material, construction, and operation before making the claim that these modules are truly sustainable. The resource efficiency of these modules need to be tested with special attention paid to the potential embodied carbon of the fabrication process. Additionally, how an individual experiences these modules on both sides of a building needs to be taken into account as well. For those inside the building, the issue of transparency is something that needs further thought. The current deployment of opaque modules on the Ritz covers most of the windows, blocking visible light from filtering into the building. While the modules do have a sun-shading component, complete shading is not the ideal way to achieve occupancy comfort. Can these modules also sustain the well-being of the building and city occupants?

··· Despite these future paths of exploration, this project has successfully began my journey into deciphering and applying the complex ideas of sustainable architecture through biomimicry.

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Bibliography “AskNature”. The Biomimicry Institute. Accessed September 23, 2020. https://asknature.org/ Beecham, Simon & Terry Lucke. “Street Trees in Paved Urban Environments - The Benefits and Challenges.”

Center for Water Management and Reuse, University of South Australia. https://treenet.org/wp-content/uploads/2020/05/Street-Trees-in-Paved-Urban-Environments-The-Benefits-and-Challenges.pdf Bennetts, Helen, Antony Radford, & Terry Williamson. Understanding Sustainable Architecture. Spon Press: London, 2003. https://ebookcentral-proquest-com.proxy.library.upenn.edu/lib/upenn-ebooks/reader. action?docID=180763&ppg=4 Benyus, Janine. Biomimicry: Innovation Inspired by Nature. New York: HarperCollins Publishers, 1997.

Billings, Frederick H. “A Study of Tillandsia usneoides.” Botanical Gazette 38, no. 2 (1904): 99-121. Accessed February 18, 2021. http://www.jstor.org/stable/2465941.

Bradly, Raymond, Ambarish Karmalkar, & Kathryn Woods. “PA Climate Report and Projection - How will global warming of 2° degrees C affect Pennsylvania?” Climate System Research Center.

“Center City.” Visit Philadelphia. Accessed May 04, 2021. https://www.visitphilly.com/areas/philadelphia-neighborhoods/center-city/ “Climate Change: How Do We Know?” Nasa Global Climate Change. Accessed May 01, 2021. https://cli mate.nasa.gov/evidence/ “Coating to Keep Consumer Products Clean Inspired by Pitcher Plants.” Ask Nature. Accessed May 01, 2021. https://asknature.org/innovation/coating-to-keep-consumer-products-clean-inspired-by-pitcher-plants/#innovation-details “Convolvulus cneorum.” Scene Outside: Plant Guide. Accessed April 23, 2021. http://aboutgardendesign. com/plant-guide/item/convolvulus-cneorum Ecole Polytechnique Federale de Lausanne. “Team creates the world’s first formic acid-based fuel cell.” Phys. org. Accessed March 02, 2021. https://phys.org/news/2018-03-team-world-formic-acid-based-fuel.html Foti, Romano, Patrick L. Gurian, Jin Wen, et. al. “Options for Achieving Deep Reductions in Carbon Emissions in Philadelphia by 2050.” Urban Climate Change Research Network North American Hub (2015).

DOI: 10.13140/RG.2.1.3861.7048 Galloway, Andrew. “Building Skin Developed That Could Cool Our Cities.” ArchDaily, July 21, 2014, https://www.archdaily.com/529486/building-skin-developed-that-could-cool-our-cities Garth, R. E. "The Ecology of Spanish Moss (Tillandsia Usneoides): Its Growth and Distribution." Ecology 45, no. 3 (1964): 470-81. Accessed February 18, 2021. doi:10.2307/1936100.

Gjerde, Eric. “Ron Resch Patent 3207558, waterbomb tessellations, and more.” Origami Tessellations. August 10, 2006. https://www.origamitessellations.com/2006/08/ron-resch-patent-3407558-waterbomb-tessellations-and-more/ Harvey, LeAnne & Rich Freeh. “Philadelphia Building Energy Benchmarking, 2019 Report.” The City of Philadelphia Office of Sustainability, 2019.

Kenney, Greenworks: A Vision for a Sustainable Philadelphia, 2016.

Lambers, Hans. “Photosynthesis,” Britannica Encyclopedia. Accessed January 29, 2021. https://www.britannica.com/science/photosynthesis/Basic-products-of-photosynthesis 120

“LEED rating system,” USGBC. Accessed March 03, 2021. https://www.usgbc.org/leed O’Neil-Dunne, Jarlath. Tree Canopy Assessment, Philadelphia, PA. December 3, 2019. https://www.phila.gov/media/20200210173518/Tree-Canopy-Assessment-Report-12-03-19.pdf https://treephilly.org/about/ Pawlyn, Michael. Biomimicry in Architecture. 2nd ed. London: RIBA Publishing, 2016.

“Philadelphia Building Energy Benchmarking Visualization Tool.” The City of Philadelphia Office of Sustainability. Accessed January 26, 2021. http://visualization.phillybuildingbenchmarking.com/#!/map?year=2018 Ralevski, Alexandra. “Folding Improves Flexibility and Rigidity: European Hornbeam.” Ask Nature. Accessed April 23, 2021. https://asknature.org/strategy/folding-improves-flexibility-and-rigidity/ Steif, Ken. “Urban heat islands & street trees in Philadelphia.” Urban Spatial. Accessed April 17, 2021. http://urbanspatialanalysis.com/urban-heat-islands-street-trees-in-philadelphia/#:~:text=This%20past%20 August%2C%202016%20was,136%20years%20according%20to%20NASA.&text=Scientists%20 call%20this%20the%20'Urban,outlying%20suburban%20and%20rural%20areas.

“Stormwater Benefits of Trees.” Tree Canopy BMPs, Accessed April 21, 2021, http://treecanopybmp.org/ tree-canopy-bmps/stormwater-benefits-of-trees#:~:text=Rain%20is%20captured%20(intercepted)%20 on,to%20as%20%22canopy%22).&text=The%20combination%20of%20these%20two,is%20referred%20to%20as%20evapotranspiration.

The Biomimicry Institute. Accessed September 23, 2020. https://biomimicry.org/ The City of Philadelphia Building Energy Benchmarking. Accessed January 26, 2021. https://www.philly buildingbenchmarking.com/ “The Miura-Ori Fold” Natural Origami, July 18, 2016. https://naturalorigami.wordpress.com/2016/07/18/ the-miura-ori-fold/ Trimble, Scott. “The Forest Canopy: Structure, Roles & Measurement.” CID Bio-Science, June 27, 2019, https://cid-inc.com/blog/the-forest-canopy-structure-roles-measurement/#:~:text=Providing%20a%20canopy%20or%20ground,the%20water%20cycle%20is%20maintained.

“Understand Urban Heat Islands.” National Integrated Heat Health Information System. Accessed April 26, 2021. https://nihhis.cpo.noaa.gov/Urban-Heat-Island-Mapping/Understand-Urban-Heat-Islands Wang, Qian, Julien Warnan, Santiago Rodríguez-Jiménez, Jane L. Leung, Shafeer Kalathil, Virgil Andrei, Kazunari Domen, & Erwin Reisner. “Molecularly engineered photocatalyst sheet for scalable solar formate production from carbon dioxide and water.” Nature Energy 5 (2020): 703-710.

“Where do Philly’s Carbon emissions come from?” Green Philly. Accessed January 26, 2021. https://www. thegreencities.com/philly/where-do-phillys-carbon-emissions-come-from/

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Figures Front and back cover: https://www.nature.org/en-us/about-us/where-we-work/united-states/pennsylvania/urban-conservation-in-pennsylvania/ Fig. 1: https://idiggreenacres.com/products/tropical-pitcher-plant Fig. 2: https://www.researchgate.net/figure/Nepenthes-pitcher-organization-A-and-its-longitudinal-section-B_ fig1_321330983 Fig. 3-6: “Coating to Keep Consumer Products Clean Inspired by Pitcher Plants.” Ask Nature.

Fig. 7: https://plants.ces.ncsu.edu/plants/magnolia-grandiflora/ Fig. 8: Pawlyn, Biomimicry in Architecture.

Fig. 9: https://www.architecture.com/image-library/features/twa-flight-center.html?collection=twa-flight-center Fig. 10: https://emke.uwm.edu/entry/milwaukee-art-museum/ Fig. 11: https://inhabitat.com/amazing-calatrava-shade-pavilion-for-the-milwaukee-art-museum/ Fig. 12: Bennets et. al, Understanding Sustainable Architecture.

Fig. 13-16: Bradly et. al, “PA Climate Report and Projection - How will global warming of 2° degrees C affect Pennsylvania?”

Fig. 17: Kenney, Greenworks: A Vision for a Sustainable Philadelphia.

Fig. 18: Delaware Valley Green Building Council, Philadelphia 2030 District.

Two Penn Center images: https://www.cityfeet.com/cont/listing/1500-john-f-kennedy-blvd-philadelphia-pa-19102/cs6281409 Ritz Carlton Hotel images: https://www.travelweekly.com/Hotels/Philadelphia/The-Ritz-Carlton-Philadelphia-p3659807; https://www.bizjournals.com/philadelphia/news/2016/06/23/photo-gallery-of-ritz-carltons-25m-renovation.html Fig. 19-24: own production Fig. 25-26: Steif, Ken. “Urban heat islands & street trees in Philadelphia.”

Fig. 27-28: O’Neil-Dunne, Jarlath. Tree Canopy Assessment, Philadelphia, PA. Fig. 29-30: own production Fig. 31: https://www.bbc.com/news/business-54390932 Fig. 32-34: own production Fig. 35: Fig. 36: https://newatlas.com/formic-acid-fuel-cell/53887/ Fig. 37: own production Fig. 38-40: https://www.nikken.co.jp/en/expertise/mep_engineering/bioskin_a_facade_system_for_cooling_ city_heat_islands.html Fig. 41: Yamanashi, Tomohiko. Innovative Façade Systems of Japan.

Fig. 42: https://www.mediaterdepan.my.id/2021/04/spanish-moss-pictures.html Fig. 43: https://islandlifenc.com/why-is-it-called-spanish-moss/spanish-moss-scales/ Fig. 44-45: Billings, Frederick H. “A Study of Tillandsia usneoides.”

Fig. 46-48: own production 122

Fig. 49: https://asknature.org/strategy/folding-improves-flexibility-and-rigidity/; Pawlyn, Biomimicry in Architecture.

Fig. 50: https://pl.pinterest.com/pin/391391023842472933/?amp_client_id=CLIENT_ID(_)&mweb_unauth_id=&simplified=true Fig. 51: Pawlyn, Biomimicry in Architecture.

Fig. 52: https://www.gardentags.com/profile/bensgarden/convolvulus-arvensis/768903 Fig. 53: http://aboutgardendesign.com/plant-guide/item/convolvulus-cneorum Fig. 54-77: own production Full bleed image on pg. 8: Pawlyn, Biomimicry in Architecture.

Full bleed image on pg. 26: https://wistar.org/research-discoveries/philadelphia-research-consortium Map on pg. 40: Google Maps Morris Arboretum image on pg. 55: https://www.publicgardens.org/about-public-gardens/gardens/morris-arboretum-university-pennsylvania Full bleed image on pg. 56: https://greengroundswell.com/beech-tree-forest-canopy-in-germany/ Full bleed image on pg 114: Pawlyn, Biomimicry in Architecture.

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JUDY ZHANG ARCH Honors Thesis | University of Pennsylvania | Spring 2021