In a truly sustainable world, we would build our homes using only recyclable materials, renewable energy and without any waste. It seems impossible – and yet that is how the rest of nature operates.
Animals and plants build structures of incredible complexity without the energy-hungry high temperatures, pressures and toxic chemicals with which we process raw materials in this fossil fuel age, and without generating useless waste. Our buildings, on the other hand, are responsible for more than 40 per cent of carbon emissions in the European Union alone. Globally, the construction industry is responsible for 30-40 per cent of solid waste, says the Organisation for Economic Co-operation and Development.
It is no wonder that architects and designers are looking to the rest of nature for inspiration. They always have: Leonardo da Vinci sketched designs for a flying machine with bird-like wings; the Wright brothers studied a vulture’s drag and lift. In the 21st century, scientific advances such as molecular genetics and nanotechnology have made drawing inspiration from nature a more precise science. Biomimicry, as it’s known in the US (or biomimetics in the UK) is, as pioneering scientist and author Janine Benyus calls it, “the conscious emulation of life’s genius: innovation inspired by nature”.
How does a spider spin silk that, on a human scale, is comparable in strength to steel, has more flexibility than rubber and could capture an aeroplane in mid-flight, all without the need for high temperatures or pressures and using only basic building blocks? If we could mimic that on a larger scale, imagine the difference it would make to our building industry. We could produce our own organic “steel” at an ambient temperature, formed from nothing more than everyday atoms such as carbon, hydrogen and nitrogen. The need to mine, transport raw materials, burn coal and produce toxic wastes would all virtually disappear. What’s more, the whole process would be solar-powered.
That is a Utopian scenario but there are other areas where progress is being made. These include digital fabrication technologies such as 3D printing that can “grow” structures that breathe and work like living systems. “It’s pre-Industrial Revolution ‘vernacular’ architecture but designed by computer,” says Dr Rupert Soar of Freeform Construction who has studied various forms of bimimicry.
“Rather than environmentally unfriendly concrete, fully recyclable high-density gypsum can be used to make structures by 3D printing. This, and other similar processes are far less wasteful of resources,” he says.
No full-size buildings have yet been made this way but if the construction industry takes to this new process as other industries have done, such as aerospace and medical enterprise – growing complicated components instead of machining them – it won’t be long. Italian architect Enrico Dini hopes to be the first, with ambitions to 3D-print a house in Sardinia.
The $170bn cement industry, a big emitter of carbon dioxide, is having a biomimicry-related makeover. Calera, the American company, is using waste carbon dioxide from flue gas to produce a type of cement in a process similar to coral growth. In a move that shows that the US government recognises the potential of Calera to turn cement manufacture from a process that emits millions of tons of carbon dioxide into one that sequesters it from power stations, the company was awarded $19.5m by the US Department of Energy last year.
Other nature-inspired building products are already commercially available: PureBond, formaldehyde-free, non-toxic wood glue, used in plywood manufacture, was developed after studying how blue mussels attach to rocks underwater. Self-cleaning paints that, once dry, repel dirt were copied from the nano-structure of lotus leaves. Ornilux Mikado glass – glazing that birds can see and so don’t fly into – was inspired by spiders’ webs.
It is no surprise then to learn that biomimicry is heralded as one of the growth areas for this century. It is a genuinely multi-disciplinary field where, for instance, a research team comprising entomologists, engineers and materials scientists is not uncommon. Last year, a report by the Fermanian Business and Economic Institute in San Diego said: “While the field today is just emerging, in 15 years biomimicry could represent $300bn annually of US GDP and could account for 1.6m US jobs by 2025. Globally, biomimicry could represent about $1,000bn of GDP in 15 years.”
Buildings with an appearance of biological forms are not new. Buckminster Fuller’s geodesic domes, similar to plankton in their geometry, are resource-efficient in their construction. However, many so-called natural buildings are simply biomorphic; attractive though they are, their similarity to biological form does not result in any increase in efficiency. Biomimetic architecture is certainly not as simple as creating buildings that reflect nature’s aesthetics.
A building cited as an example of biomimicry is a conventional-looking 1990s shopping centre and office block, the Eastgate Centre in Harare, Zimbabwe. It was designed, by architect Mick Pearce, to regulate its temperature like a termite mound. It maintains its temperature within a range of a few degrees, despite external fluctuations from 5C-30C and using just 10-20 per cent of the energy that a similar block would use for air-conditioning. “Buildings that adapt to changing conditions is the way we have to develop if we are to mimic truly the low energy ways in which biology works,” says architect Michael Pawlyn, whose book on the subject, Biomimicry in Architecture, is published next month.
Dynamic “building skins”, which have only become familiar in the past decade, are expected to grow in popularity. One example is Upper Riccarton Community and School Library in Christchurch, New Zealand. The building was designed with an “intelligent skin” of louvres and windows that respond to sun, wind, rain and temperature to maintain an internal constant. The library’s closure since the earthquake in February is a poignant reminder of the power of nature.
Building flexibility, which could safeguard against the impact of earthquakes, is heralded as another advantage of copying the natural world in architecture. “Everything in nature is flexible,” says Tristram Carfrae, board director of Arup Group. “Flexible structures will be the next step,” he says. “That is the main benefit of biomimicry.” Carfrae designed the Water Cube at the 2008 Beijing Olympics that copies the natural formation of soap bubbles. This organic form makes it highly earthquake resistant.
As well as individual buildings, biomimicry could influence how we plan our cities. “New cities should do at least as well at ecosystem services as the natural systems they replace,” says Benyus. Her consultancy, the Biomimicry Group, has designed “ecological performance standards” to make sure new developments perform as well as the local ecosystem they replace in, for example, storing and filtering water, sequestering carbon and creating topsoil.
“We are developing entirely new ways of working, to create a built environment that works like natural systems,” says Chip Crawford, director of planning at HOK, which employs the Biomimicry Group. HOK is working on new cities in India such as Lavasa, where steep valleys that receive nine metres of rainfall in a three-month period are erosion-free. To ensure this continues, buildings have canopy roofs to hold water and permeable pavements.
Restorative development, where we heal degraded ecosystems, is another potential benefit of this modus operandi. In Roman times, the deserts of North Africa were fertile, crop-growing regions. There are plans to re-green areas of the Sahara in a project that combines seawater greenhouses and concentrated solar power. In the Sahara Forest Project, in Jordan and Qatar, seawater greenhouses will harness fresh water through condensation; a technique used by Namibian fog-basking beetles. Biomimicry, it seems, offers us a greener future.