Bacteria Building for Sustainability: The Convergence of Design and Biology in the 21st Century
The imitation of nature in design is an old phenomenon, recalling stylistic developments such as iron-enabled Art Nouveau all the way up to titanium-clad fish shapes in the computer-aided designs of architect Frank Gehry.
What is prompting new intersections of design with biology, as seen in architectural technologies, design proposals, and the increasing practice of biomimicry? What are the goals and implications of these intersections, and how do they relate to changes observed in the past? Does this development amount to a paradigmatic shift in design practice? If so, how is it like others in the trajectory of historical developments, such as industrialization and the adoption of computer technology?
The intensifying pressure to achieve the efficiency of natural systems is altering design practice, leading designers to collaborate with biologists in ways that are rich with implications and potential outcomes. Such new collaborations are set to multiply, particularly as the phenomenon of do-it-yourself biology proliferates and the urgency to achieve the harmonious cycles of material and energy usage found in nature becomes widely accepted. This convergence of different fields as well as the expert with the amateur is ultimately necessary to alleviate the negative impacts made by the legacies of the Industrial Revolution and will be characterized by new conceptions of value, growth, and sustainability.
“It will be soft and hairy.”(Salvador Dalí on the future of architecture, in response to Le Corbusier.)
The accelerating degradation of the environment is forcing designers to recognize the fragility of nature and our responsibility to preserve it for future generations. Some designers are beginning to emulate and harness processes observed in the living world, where systems can function with a perfect economy of energy and materials. Within this pursuit, working to achieve sustainability through a new type of biomimicry, these designers are turning to biologists for their expertise and guidance.
The imitation of nature in design is an old phenomenon, recalling stylistic developments such as iron-enabled Art Nouveau all the way up to titanium-clad fish shapes in the computer-aided designs of architect Frank Gehry. Yet, these designs are form-driven and make only a superficial likeness to the natural world for decorative, symbolic, or metaphorical effect. Designing to begin to achieve the qualities that actually generate these forms, for adaptability, efficiency, and interdependence is infinitely more complex, demanding the observational tools and experimental methods of science. Thirty years ago science progressed to a point of knowledge and technique that enables the building of primitive, but functioning organisms and ecosystems to harness life for special applications in medicine and materials production. But in the last ten years this kind of technology has become accessible enough to be considered viable tools by engineers and designers.
In the nineteenth century, a combination of standardization of measurements, the Bessemer steel-making processes, and the steam engine converged to enable the Industrial Revolution, answering the call of democratic, capitalistic nation-states seeking market growth. A key component of this development was the dropping price and increasing quality of steel, which quickly moved from $170 per ton in 1867 to $14 per ton before the end of the century. Similarly, what became known as Moore’s Law in the late twentieth century, or the doubling of computing power (as measured by the number of transistors fitting onto an integrated circuit) every two years, amplified by the rise of the Internet and the world-wide adoption of standards like HTML, supported a digital revolution. Computer technology exponentially spread and intensified the effects of the Industrial Revolution, and addressed the forces wrought by globalization, particularly the necessity to successfully compete in foreign markets, manage increasingly complex commodity exchanges, and to achieve continual economic expansion in order to maintain low unemployment and stable governments.
In the first decade of the twenty-first century the forces that prompted industrialization and digitization persist, but a new, more urgent, and arguably longer-term need has arisen that calls for a new revolution: the need for sustainable practices in design which guide resource management, particularly manufacturing and building. The pace of world economic development and the consumption of scarce natural resources, including fossil fuels, cannot be maintained. The scale and scope of human activity and projected changes in climate, demand, and access over the next several decades demand new standards of energy efficiency, waste elimination, and biodiversity protection.
A model for such rigorous standards has only been found in nature, the emulation of which now moves beyond stylistic choice to survival necessity. Driven by research in biology, the mechanisms of natural systems, from swamps to yeasts, are quickly being decoded, analyzed, and understood. The architectural program of many of these systems is DNA, the sequencing and synthesis of which is very quickly becoming inexpensive, much like steel and computing power in previous centuries. A sharing of expertise across disciplines, including design, is needed to achieve sustainability in this emerging field of research.
Up until the seventeenth century the sciences and the applied arts, such as architecture, shared much closer ties. As argued by Hugh Aldersey-Williams in his essay “Applied Curiosity” in Design and the Elastic Mind, dominant figures in the sciences, including the founders of the Royal Society, also included practicing architects. The rift widened as objectives changed and specializations developed, as expressed by industrialist and potter Josiah Wedgewood: “I have got beyond my depth…These wonderful works of Nature are too vast for my narrow microscopic comprehension. I must bid adieu to them for the present, and attend to what better suits my Capacity. The forming of a Jug or Teapot.”
Today, this rift is narrowed by necessity. We recognize that designers do not actually create things like teapots or buildings, but instead act as initiators of systems of resource collecting, labor application, manufacturing, marketing, distribution, consumption, and disposal. This, all in the name of a teapot or high-rise, presents a uniquely complex set of problems and supports the assertion that there are no things as things, only systems. These problems are brought to bear as it is acknowledged that the consumption of irreplaceable resources and the loss of biodiversity driven by economic development cannot be sustained. Consequently, systems of nature and the biologists who work to understand them must be consulted. Only this type of consilience can help bring the material existence and practical utility of objects into a harmony similar to that of nature.
Self-Healing Technology: The Evolving Goals and Design of Concrete
The urgency of the demand for material sustainability and ecological preservation grows even as the world experiences an economic downturn. At current rates of production and consumption, carbon emissions would lead to an uninhabitable climate for much of the planet within 200 years. Responding to this set of conditions is not unlike the exercise of considering how to build in a desert with precious few resources, as shown by the young architect Magnus Larsson in his project Dune. Ultimately, the needs of this extreme environment force designers to examine and replicate life: the only resource management system that is known to function indefinitely and even within conditions as forbidding as a desert. An illustration of this successful replication or biomimicry can be seen in the realized design by Mick Pearce of an office complex in Zimbabwe modeled after the self-cooling mounds built by termites, resulting in a 90% savings of energy required for ventilation and air conditioning.
For much of history, performance and quality were measured by the degree to which a designed material, object, or structure addressed a set of needs only once it was completed and handed off to the user. This primacy and narrow definition of function is no longer valid. In the twenty-first century it is being replaced by a new, more sophisticated understanding of factors such as the impacts of carbon emissions, trade policies, and resource scarcity. As a result, the performance of a design must be judged by a much larger set of criteria. Dependence on limited fossil fuels and the use of wood extracted from endangered woodlands are just two examples of non-sustainable practices that cast a new, critical light on petroleum-derived products and particular wood furniture. Among the new criteria only hinted at here, those related to environmental impact have emerged as the most urgent, particularly energy efficiency and economy of materials.
These new criteria inform many of the goals of research and development in materials and building technology. Among all other products, the effect of these new goals may fall first on concrete, the production of which is energy intensive, responsible for 5% of all annual global carbon emissions. Nearly three billion tons of concrete are produced in the world each year, a figure that grows 4% annually as the pace of building in developing economies accelerates. Such a common and yet consequential material is, not surprisingly, the subject of much research and experimentation and is the focus of a new development of particular interest by the Delft University of Technology in The Netherlands.
Lead by Dr. Henk Jonkers, researchers at the university’s Centre for Materials, the Self-Healing Materials program has yielded a new type of concrete that, when cracked is able to heal itself using the living bacteria suspended within it. In a process known as microbial cementation, cracks are sealed internally by the formation of calcium carbonate by the exposed bacteria. In what has been named Bioconcrete, bacteria are mixed with the cement, water, and aggregate and survive the processes of hardening. Normal concrete inevitably cracks, admitting moisture and oxygen inside and resulting in a loss of material strength as the freezing of moisture over time widens the opening. In theory, Bioconcrete would prevent, or at least greatly delay this process, which afflicts all concrete, and thereby alleviate the need for costly repairs and replacement. When considered on the scale on which concrete is used and maintained, this represents significant savings. For each ton of concrete produced, approximately an equal amount of carbon dioxide is emitted, most from the process of calcination – heating limestone to above 1,400 degrees Fahrenheit to obtain calcium oxide.
The development of Bioconcrete is, in many ways, analogous to the rediscovery of concrete and the development of a method of its reinforcement in the eighteenth and nineteenth centuries in the sense that it has arisen from the pressing societal need to develop new performance in building. The bricks and stones that preceded reinforced concrete were considerably more expensive to obtain and transport when compared with the reinforcing material and mixing concrete on site. In addition, the tensile strength of reinforced concrete vastly expanded both the functional and aesthetic possibilities of architecture. In Bioconcrete we can observe an attempt to greatly reduce the long-term cost of building, maintaining, and replacing structures—a recognition that strength and stability is multi-dimensional in the current age. Its successful implementation would result in the need to produce far less concrete, and emit considerably less carbon. This effort, grown out of the Bio- Civil/Geo Engineering program in Delft, is grounded in the assumption that utilizing natural systems in design is consistent with the goal of eliminating waste.
One of the longer term goals of the research in which Jonkers and his peers are engaged is to understand the best methods of introducing living cells into common materials, to learn how they will react to different levels of pH, temperature, and availability of nutrients and moisture. In turn, this may enable new applications for hybridizing living and non-living matter. In the case of concrete, an eventual goal is to make bacterial cement that can produce its own calcium oxide in an organic reaction, supplanting the existing, and energy intensive, carbon-emitting procedure of mining, transporting, and burning limestone.
The growing field of synthetic biology suggests that this kind of application will be possible within 10-15 years through the process of engineering bacterial DNA. Already, such applications have been developed to harness bacteria to produce PLA plastic and anti malarial drugs using dramatically less energy than conventional means. More generally, this research fits into a new and growing field of inquiry into how materials can emulate both the economic and regenerative qualities of living systems.
Concrete presents itself as an important indicator of the direction and priorities of architecture since its application is so vast and integral to basic infrastructure. Subsequently, as concrete changes, we can see reflections of the forces influencing researchers and designers in general. Bioconcrete, like the first examples of reinforced concrete signals an attempt to address a new set of urgent societal forces, particularly the need to reduce the negative impact of architecture on the long-term health of the environment. The new infrastructure of the twenty-first century is thus one that may have to be quite literally alive to function in accordance with our needs.