When a shimmering, 600-foot glass tower was erected in London in 2004, it replaced a building that had been destroyed by a terrorist bombing. Yet the inspiration for the tower’s unique, missile-like design was not militaristic: it was the Venus' Flower Basket sea sponge, a glowing creature that thrives in the inky depths of the sea.
The animal is distinctive because it creates a shiny silicon-based material that bonds together, forming a grate-like exoskeleton that gives it structural strength but also filters water and nutrients efficiently. Much like the sea sponge maneuvers water through its lattice-like exoskeleton, Lord Norman Foster's tower -- officially 30 St Mary Axe, but better known by locals as "The Gherkin" -- directs the flow of winds from street level and open windows along its spiral body, funneling it through the buildings offices naturally and reducing by almost half the need for energy-sucking air conditioning.
The world’s population is seven billion and climbing, and our built environment -- and by extension, the pollution produced by manufacturing the materials needed to make and sustain it -- is undergoing radical change. Experts at the United Nations Intergovernmental Panel on Climate Change say the way we build and retrofit our cities, more than any other thing humankind can do, is number one tool the world can use to reduce greenhouse gases.
Years after Foster’s influential project, architects, scientists and designers are digging ever deeper into the natural world -- even to microscopic levels -- to seek answers to vexing design questions by mimicking biological systems that have already solved them, solutions developed over billions of years of evolution. This movement in search of "biomimetic" architecture has forged increasingly unlikely alliances between synthetic biologists, botanists and other scientists with artists, builders and materials makers to make structures that work with nature, not against it.
“In nature, every organism has to be as efficient as possible with its use of resources. There’s no way an organism can use more energy than it produces,” said Alexis Karolides, an architect with the Rocky Mountain Institute in Boulder, Colo. who works on infusing biomimetic principles into efficiency projects for corporate and industrial clients.
“Inefficiencies were eliminated through natural selection over billions of years. Why put tons of solar panels on a roof when you can make the building efficient in the first place? Think of how nature designed it first with a form and a function in mind.”
Right now, biomimetic innovations have already provided revolutionary ideas for how new buildings are cooled and heated, one of the most energy intensive systems in a structure. Unlocking these biological secrets -- how an animal cools itself, such as using its body to absorb water in a hot, arid landscape where life sustaining resources are rare -- has already provided tangible advances in sustainable design.
LEARN FROM THE TERMITES
The Eastgate Centre is a massive retail and office building that takes up half a city block in the sweltering confines of Harare, Zimbabwe. Architect Mick Pearce looked at the way termites built their tower-like earthen mounds, which rise like crooked fingers from the country’s savannah, for inspiration on how to naturally cool the site.
The termites would otherwise die in the stifling desert heat. The construction of their mounds employs an architectural system that captures desert breezes from above ground and funnels them to a series of subterranean chambers, where the moist earth is cooler. The cooler air is then redistributed through the mound; warm air is sent out through a flue in the top of the mound. The design helps the termites regulate the temperature in a region with wild weather fluctuations.
Pearce’s Eastgate Centre uses fans to move cool night air through chambers under office floors, which can be sent through the building during daytime heat. The building is cooled at one-tenth the cost of structures with old fashioned, energy-sucking air conditioning.
The practice of modeling structures after those of nearby animals is a time-honored tradition with ancient roots, said Taryn Mead, a senior biologist at Biomimicry 3.8. Mead works with designers and architects to translate the biological world into building projects.
"Historically, humans have always been looking to other organisms to inform them about their environment," she said. "As the story goes, the Inuit in far northern North America looked to polar bears to see how thick the walls of their igloos should be. The bears had configured the snowpack to stay warm."
“In the deserts of the American Southwest, native people studied how thick the mud walls of prairie dog chambers were to determine the best way to stay cool in that environment.”
Biomimetic principles are already transforming public spaces in the most densely populated areas of the U.S., in projects that are providing a template for the next generation of planners and architects who will be in charge of accommodating the world’s ever expanding population.
Collaborations between designers and botanists are finding pragmatic ways to blur the line between manmade construction and nature. Some consider it the reforesting of cities, where commercial rooftops and old industrial infrastructure are repurposed into a living part of the built environment.
In San Francisco, one of the most densely populated places in the U.S., the Italian architect Renzo Piano worked with local botanists to create a new kind of living roof at the California Academy of Sciences, which features 1.7 million plants that replace an inefficient traditional hard roof with a field of California poppies, tidy tips, sea pink and other native plants.
While roof gardens and living roofs have been around for generations, Piano’s version is constructed with seven small, plant covered hills that help funnel the cool sea air flowing in from the Pacific Ocean into grates. A series of weather instruments on the roof are linked to a computer, which trigger the roof vents to open and close, regulating the flow of natural air through the museum below.
In New York, designers and architects James Corner Field Operation and the firm of Diller Scofidio and Renfro worked with planting designer Piet Oudolf to repurpose an unused, rusted and decrepit elevated railbed -- the "High Line" -- into a park. Space that was unused in a dense city is now teeming with life, and increased the size of public space in a city with no physical room to grow.
“It’s parkland moving across an industrial object. It's accomplished a quite wonderful thing in the preservation and recognition of the industrial legacy,” said Dennis Dollens, a professor of architecture at the Universitat Internacional de Catalunya in Barcelona. “And there’s the utility of moving above the city streets, which actually adds to the size of the city. In this sense it becomes a prototype for the reforesting of cities, and not taking out huge swaths for redevelopment but finding places and different ways of growing cities.”
Yet green roofs and projects like the High Line still require a good deal of energy to sustain, so some architects are working with synthetic biologist to create building materials that could be applied to the walls of existing buildings that could suck greenhouse gases from the air, and create a natural shell to both better insulate and strengthen buildings.
Dollens has developed a biomimetic architecture iPhone app called “BioDesign,” which explores in a comic-book like fashion the engineering and modeling of the buildings of the future. Dollens’ app explores the structural properties of trees and leaves, such as how they take stress from a disaster like an earthquake or repel water.
“At this moment buildings are made of materials that are very difficult to recycle, sometimes impossible," Dollens said. "There are enormous amounts of energy that goes into demolition or materials that are tossed into waste sites and landfills and oceans."
“We're looking for resins to replace plastics, and new ways of reformulating earthen products like adobe. How could adobe become a wall material that could be used in a skyscraper? How do you put a binder in it and make it thing where you still have a high level of performance but it’s a very different material than an adobe brick today."
THE BUILDINGS ARE ALIVE
While today’s biomimetic architecture incorporate pieces of nature into buildings design, new laboratory research seeks to make actual living materials for use in architecture. The concept makes Foster's and Piano’s approaches seem quaint by comparison.
Bioluminescent bacteria may soon provide lighting, free of electricity from the grid. Bacteria attached to walls will grow in decorative patterns and turn colors when certain pollutants are introduced.
English physician and synthetic biologist Rachel Armstrong and architect Neil Spiller, head of the School of Architecture and Construction at the University of Greenwich in London, are working together to develop these kinds of materials, including a chemically-responsive “skin” that could be painted on buildings, growing a shell that could eat greenhouse gas pollutants and strengthening buildings.
“The tools of synthetic biology are galvanizing the development of new forms of architecture that respond to environmental change by incorporating the dynamic properties of living systems, such as growth, repair, sensitivity and replication,” Armstrong and Spiller wrote in a piece published last year in the journal Nature.
In an interview from a lab in Denmark, Armstrong said the carbon-eating paint, which she calls “Biolime,” is tied up in intellectual property issues at the moment. She described Biolime as like a child’s “crystal garden,” where colorful crystals grow once the minerals are submerged in water.
“Essentially it creates artificial shells around soft little fatty bodies,” Armstrong said. “They are an accretion technology which recruits other minerals to the site and essentially can potentially grow an artificial skin.”
As the shell grows it could help better insulate and strengthen a building, and Armstrong said the building blocks of Biolime and are small chemical droplets called “protocells,” which can be designed -- or “programmed,” as Armstrong likes to say -- to remove carbon from the atmosphere.
Armstrong, who is a TED fellow, also proposes to use the protocell technology on an architectural scale to save centuries-old Venice, Italy, which is gradually being reclaimed by the sea. Armstrong believes the protocell droplets could be deployed beneath the crumbling city to act as a living limestone foundation.
“We did some experiments inside the Venice lagoon with architecture students and we know it works with the Venice water,” Armstrong said. “It’s not ready, but the principles are there. It just needs some more research and development.”
All of this work is evolving at a quick pace, pushing architects, designers, biologists and other scientists to rethink how are cities and buildings mesh with the natural world. Now, using technological innovation coupled with inspiration from the biological processes of nature, these dreams are becoming a reality.
"We are now looking to traditional forms and methods for highly technological transformations, the way people are looking to biology for changing a transistor or a chip," Dollens said. "How do we apply that kind of vision to architecture and still expect performance?"
Photo courtesy 30 St Mary Axe
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