As towns and cities continue to encroach on agricultural and wilderness areas, many researchers, town planners and architects are thinking about another approach: biomimicry.
L'Atelier BNP Paribas - June 2017, by Alain Clapaud
According to figures published by the United NationsMore than 50% of the world's population now lives in urban areas, and this figure will rise to 70% by 2050. In France, almost 80% of the population already live in cities that drain energy, food and consumer goods over hundreds of kilometres. These sprawling cities have often been built with little regard for their environment. They are devastating for biodiversity and have a large environmental footprint. They are also highly vulnerable to climatic hazards. Given the ever-increasing urbanisation and the effects of climate change, some people believe that we now need to rethink the way our cities are designed and built. " It's time to change the paradigm and draw inspiration from nature to reconnect cities with the environment. "says Olivier Floch, organiser of Biomim'Expo with the Ceebios (Centre Européen d'Excellence en Biomimétisme de Senlis) who adds " We need to re-vegetate our towns and cities, because the more people are in contact with nature, the better off they are!. Experts in what is known as biomimicry believe that we need to copy, or rather draw inspiration from, nature in order to design cities that are more liveable for their inhabitants and have less impact on the environment.
Biomimicry, a concept that is making a comeback
Biomimicry is an approach that has been around for a very long time. With his flying wing inspired by birds, Leonardo da Vinci is undoubtedly one of the most famous precursors of a discipline that has been brought up to date by the American biologist Janine Benyus. She emphasised the great resilience of nature in the face of the worst disasters, a model for the design of cities of the future. " It has identified between 17 and 20 biomesecozones" that are remarkable for their qualities, their resilience explains Olivier Floch, using the example of one of these biomes, identified in India. "Every year, millions of m3 of water pour into this area during each monsoon. These colossal volumes of water are absorbed by an incalculable number of plants that have developed a unique capacity to absorb water. Similarly, mangroves are increasingly seen as a natural bulwark against the rise in water levels expected over the next few years. Observing nature provides us with new insights into how we can redevelop our cities". Today, these biomes are being analysed in detail by researchers with a view to copying them, or rather transposing them to towns and cities. Wetlands planted with reeds in parks to pre-filter run-off water, green roofs and green ditches are just some of the many solutions inspired by natural ecosystems. More and more mayors are turning to these nature-inspired solutions to make their towns and cities more resilient to the vagaries of the weather.
For example, following the floods that paralysed New York after Hurricane Sandy in 2012, former New York Mayor Michael Bloomberg created 100ResilientCitiesThis initiative brings together cities from all continents, in both developed and emerging countries. The initiative brings together cities from every continent, in both developed and emerging countries, and promotes the sharing of experience in areas as diverse as the fight against floods, hurricanes and earthquakes, as well as ageing populations, social inequalities and crime.
The architectural firm HOK has imagined restructuring the Indian town of Lavasa into 5 villages capable of accommodating between 30,000 and 50,000 inhabitants, with a limited environmental footprint (Photo credit: HOK)
An expert in the sustainable development of business districts, Guillaume Porcheron, Project Manager at Versailles Grand Parc, believes that this bio-inspired approach could be applied anywhere in the world: " The local biotope needs to be carefully studied. Today's cities are increasingly designed to be above ground in relation to their natural environment. A traditional village in an oasis was built by adapting to its environment, as opposed to a city like Dubai, which is nothing more than a Manhattan in the desert. Today, we reproduce this model all over the world, with the result that we create cities that consume a lot of energy and don't age well in the face of the elements. For me, the ideal city means fluidity for everyone: the inhabitants, the plant and animal species.
While it is possible to apply the precepts of biomimicry on the scale of eco-neighbourhoods or new towns, their implementation can also help to improve the existing urban fabric. City planners are beginning to clear away the heat islands that form in areas devoid of vegetation, planting trees to limit the heat during hot spells and thus improve the well-being of local residents. It is also possible to reintroduce a little biodiversity into urban areas, in particular by seeking to develop green and blue webs in cities. Linking these grids together promotes biodiversity throughout the city. In contrast to the mineral cities where concrete was the rule (the La Défense slab in Paris), ecologists are now pushing for the creation of brown grids, areas of permeable soil capable of absorbing rainwater. This approach is advocated by Marc Barra, an ecologist at Natureparifregional nature and biodiversity agency: " Cities have a cumulative impact on nature through urbanisation, soil sealing, pollution and fragmentation. Beyond the observation that nature is not doing well, there is also a direct interest in health, well-being and quality of life, as well as an economic interest. Reintegrating nature into urban development can be less expensive than conventional development, and concrete costs more than vegetation. Natureparif is carrying out a study in various areas where biomimicry is applied and intends to demonstrate that, in addition to the purely ecological aspects and the well-being of residents, there can be a real economic interest in implementing alternative approaches.
Architects and builders also on deck
The construction industry and architects are showing increasing interest in biomimicry concepts. The famous Bosco vertical " by Studio Boeri in Milan inspired the future M6B2 tower to be built in Paris in the 13th arrondissement. " An analysis of these projects shows that the plants and trees in the Bosco Vertical towers have to be watered using drip irrigation. Over the entire life cycle of the building, its environmental footprint remains high. These projects are interesting as demonstrators, but other approaches are more effective. I have a lot more faith in the "25 verde" project in Turin, designed by the architect Luciano Pia, whose approach requires much less watering and maintenance. His vision is more humane in terms of neighbourhood life. "
More and more architects are beginning to incorporate the principles of biomimicry into their work, like Nicolas Vernoux-Thélot, Architecte DPLG at In Situ Architecture : " As an architect, this approach speaks directly to me because it pushes innovation with an environmental and ecological dimension. This awakening to biomimicry goes back to a meeting with a plant biology researcher at the CNRS, Teva Vernoux. 10 years ago, we realised that a habitat and a plant have several things in common: they are both immobile, they require natural light to function, they need water and they are subject to external climatic constraints (wind, heat, cold, etc.). The parallel between plants and buildings seemed to us to be particularly fruitful and promising for architecture. "An R&D partnership now unites In Situ Architecture and the Reproduction and Development of Plants laboratory of the CNRS. " We have developed a bioinspired digital model that enables one or more buildings and their various parts to be projected onto a site as densely as possible in order to optimise their exposure and passive energy input. The immediate gains are the energy efficiency of the buildings and the good health of the occupants. "For Nicolas Vernoux-Thélot, the implementation of the precepts of bioinspiration does not stop at large-scale projects commissioned by the public sector or at the campuses of major companies: " Even with a standard implementation and thus controlled construction costs, a building and its parts can be organized in such a way that its occupants benefit from the best sunlight and see their energy expenses decrease significantly thanks to the contributions of passive energy from the sun. Plants do it wonderfully, why not a building? "
As well as pioneering architects, construction giants such as Ceebios member Eiffage are also interested in biomimicry. Iswann Ali Benali, a member of EIFFAGE's Sustainable Development and Transverse Innovation Department, points out: " For Eiffage, biomimicry is seen as a lever for innovation in our research into sustainable cities. In 2007, we set up a foresight laboratory called Phosphore, with the aim of imagining the city of the future. This R&D project brought together around a hundred of the Group's employees. The laboratory generated a series of conceptual and technical innovations that we are now trying to implement in our operational projects, notably eco-districts and new public facilities. This is particularly true of the Euroméditerranée 2 eco-district built by Eiffage in Marseilles, which is a kind of demonstrator of the concepts devised by Phosphore.
Eiffage is also interested in urban agriculture.. "This is an area that is a little more mature and one that we can promote in our eco-district projects," explains Iswann Ali Benali. "We have worked with Inspire Institute on its urban farm concept La Marcotte" An educational project to explain how urban agriculture, with its short circuit and closed loop logic, can be integrated to enhance the value of on-site production. Finally, Eiffage is interested in new construction processes, in particular 3D printing, which will make it possible to reproduce shapes inspired by nature that are difficult to achieve using current construction methods. Better still, new bio-sourced materials such as straw and wood could be more widely used in construction, thereby reducing the environmental footprint of new buildings. Among the research projects that have attracted Eiffage's attention are those of the XTU architectural firm. Architects Anouk Legendre and Nicolas Desmazières are proposing to apply facades containing microalgae to buildings. "Their algofaçade concept could soon be implemented on one of our projects in the Ile-de-France region. hopes Iswann Ali Benali. " There's a promise of thermal regulation of the building and possible use of biomass, but the problems associated with maintenance have yet to be assessed. It's still an emerging innovation project and we're making gradual progress. A demonstrator will be used to test the solution before considering its industrialisation. "
Another French start-up is also working on microalgae with the aim of depolluting city centres. Fermentalg is working with Suez to develop "Morris columns", glass cylinders which, when placed in the most polluted areas of major cities, trap CO2 and generate oxygen. " What's doubly interesting about this approach is that these microalgae not only trap pollution, but also generate a biomass which, if properly exploited, will produce methane gas to supply homes or district heating". explains Olivier Floch who adds: "We are finally beginning to see waste as a resource, particularly for urban agriculture. In this way, we are entering a virtuous circle that will lead us, not to total autonomy for cities, but at least to limiting the way in which they draw on the planet's resources.
Startups such as Glowee or Tangram Architects are exploring another direction, not to produce energy, but to light up the city of the future. Inspired by the bioluminescence of plankton, their devices could one day light our streets with a soft light that has the advantage of being less aggressive than current lighting, whose negative effects on biodiversity are now well known.
Producing energy in the heart of cities, a technological challenge
While ecologists dream of one day creating self-sufficient cities, energy remains a key issue in reducing the environmental footprint of cities. " An ecosystem is a system that lives on itself and depends solely on solar energy and water. "says Olivier Floch. The problem of energy remains unresolved, because making cities self-sufficient, since they alone consume 40% of the energy consumed on the planet, is a complex challenge. Researchers and architects are pursuing various avenues, including covering buildings with solar panels and wind turbines.
Although there have been a few attempts to integrate large wind turbines into towers in the Emirates, this approach seems unrealistic at present. Faced with the drawbacks of wind turbines as we know them today, researchers are considering copying whale skin to eliminate the noise caused by the blades, while the Moroccans from Tayer Wind propose to copy the wings of the hummingbird. Even more original, the design firm Atelier DNA has come up with the Windstalkan artificial reed capable of generating electricity by lying down facing the wind. These quieter wind turbines may one day find their way into towns and cities, but the initial investment is still high and the commercial failure of Newwind with its urban wind turbine inspired by a tree, shows that it is still very difficult to find an economic model.
With its falling prices, photovoltaics is emerging as a means of producing energy in the heart of towns and cities, but the energy yield of panels, ranging from 24 to 25% for the most efficient, is still insufficient to meet all the needs of a town or city. Many experts are pinning their hopes on research into artificial photosynthesis. Imitating plant photosynthesis, researchers are aiming for yields close to 100%. Solar energy would then become an abundant and inexhaustible source of energy, without having to mobilise huge areas of land to the detriment of agriculture. Numerous research laboratories around the world are working to develop devices that will generate energy faster and more efficiently than natural photosynthesis, but it will be many years before the technology is mastered and finally available on an industrial scale.
Nature's intelligence could even find its way into the control algorithms of the millions of drones and autonomous cars that will be criss-crossing the streets of these cities of the future. Researchers are drawing inspiration from the behaviour of schools of fish and the flight of starlings to develop algorithms for regulating urban traffic. When you consider that a swarm of starlings can number several million individuals and move rapidly without any of them colliding with their companions, nature still has a lot to teach us.