How Biomimicry Inspired Creating A Ship from 12,000 Plastic Bottles (Videos)
Photos via The Plastiki
Text written by Michael Pawlyn, Director, Exploration Architecture.
I met David de Rothschild at the Google Zeitgeist conference in 2007 where we both spoke during the session about Green Technology. He explained his idea of the Plastiki Expedition and I was immediately captivated. It had exactly the right combination of elements to appeal to my interests: eccentricity, high idealism and a clear determination to bring about positive change. I had not previously heard about the Pacific garbage patches and I was struck by the way that they represented a very powerful metaphor for the way we treat the oceans - we behave as if the sea has a limitless capacity to absorb our pollution and as long as it is out of sight we're not bothered. They are also a clear example of what is wrong with our current paradigm which involves using resources in a linear, wasteful and polluting way. Much of the pollution that exists in the garbage patches is plastic waste which gradually breaks down into short lengths of polymer which absorb other pollutants and accelerate their uptake into the marine food-chain.
Check out how the duo created the Plastiki using inspiration including how eggs are bundled in Japan to the humble pomegranate.
David was very complimentary about my talk on biomimicry, which was about looking to nature as a source of inspiration for new technological solutions, so we met up after the conference and started to develop design ideas. We also shared an interest in the Cradle to Cradle concept developed by Bill McDonough and Michael Braungart which proposes a way in which we can shift from a linear way of using resources to one that keeps all resources in closed cycles so nothing is wasted and no pollution is emitted. There are many areas of overlap between biomimicry and Cradle to Cradle particularly in the way that ecosystems present a great model of closed loop systems in which any waste from one organism becomes the nutrient for something else in the system. We can learn a lot from the way that natural systems work in rethinking our own systems and designing out the whole concept of waste.
The brief for the Plastiki Expedition was to design a boat made out of plastic bottles that could be sailed across the pacific on an expedition that would draw attention to the problems facing the oceans as well as the kind of solutions that we need to implement. We agreed that, to set the right example, the boat should be designed to be fully recyclable at the end of the journey, generate all its own energy and emit no pollution. We also felt that the bottles should be used intact rather than simply melted down into a sheet material and turned into a conventional boat.
Check out the full sized image at Plastiki
The first challenge was to find a way to turn a very weak material (plastic bottles) into a structure that would withstand the forces likely to be experienced on a voyage through the Pacific Ocean. We took our inspiration from a number of examples that included the way that eggs used to be packaged in Japan (tied together with reeds so that the eggs are held firmly in compression) and the traditional structures built entirely out of bundles of grass in what is now Iraq. Both were examples of how, with design ingenuity, something flimsy or fragile can be turned into something robust. However, the source that provided the greatest break-through was a pomegranate. When I was cutting one up I realized that each individual segment had a degree of internal pressure and by packing them together in a geometrically compact way, filling the gaps with pith and surrounding them all with a tough skin the end result is a very resilient form. This led to the idea of pressurizing each bottle with air - a simple move that transformed the bottles into incredibly solid objects. In our tests we proved that just by adding air pressure it was possible for two plastic bottles to support the weight of a car.
David de Rothschild Explains Building the Plastiki to Graham Hill
The first sketches were based on the idea of forming bundles of tightly packed bottles with some framing members and a tough skin on the outside. This subsequently developed into a scheme that created a core of sheet material (made from recycled plastic bottles) into which the bottles would be packed to provide stiffness as well as buoyancy. This was the scheme that was taken forward to construction by the naval architect Andy Dovell. David's team later found a supplier of a revolutionary sheet material called SrPET that uses recycled plastic bottles in two forms - one like a fiber and one like a resin - so that when put together they create a material that is very similar to fiberglass. However, unlike fiberglass which is impossible to recycle, the SrPET is made entirely from one material and can be recycled indefinitely with no loss of resources or material quality - the holy grail of Cradle to Cradle design.
Check out the full sized image at Plastiki
The design of the systems on the boat presented other challenges. While it is common for conventional ocean-going vessels to discharge their food and sewage waste into the sea and fumes from fossil fuel powered engines into the atmosphere, David and I were adamant that the Plastiki should not emit any pollution at all. Generally zero waste technologies are easier to achieve at large scale so if we could demonstrate that this was possible on a small scale, it would send a powerful message to the larger ships which currently treat the ocean as a vast sewer. For the energy, we explored a range of renewable technologies including wind turbines, sea turbines, photovoltaic panels and even a new form of anaerobic digester that could generate hydrogen from human waste. The eventual solution used a combination of renewable energy generation forms in order to provide consistent power supply. This was backed up with a pair of exercise bikes linked to generators to keep the crew fit!
Providing fresh water for the crew led us to develop a custom-made desalination system inspired by a beetle that has evolved to harvest its own water in a desert. The beetle is a terrific example of what biomimicry can offer - ingenious solutions to resource-constrained environments. This offered the potential to turn seawater into distilled water just using the sun, the wind and a small amount of pumping energy. While we demonstrated that the system would work in principle there was not time to develop and refine the system to a level that we could completely rely on. We had to be realistic about what was achievable within the limitations of a small project but nevertheless we discovered some excellent solutions such as kite sails and innovative approaches to deriving energy from waste that would offer great potential for subsequent projects.
It was very satisfying to see the concepts of biomimicry being taken through the whole project including the design of the cabin by Nathaniel Corum of Architecture for Humanity and the first use of a completely non-toxic type of glue as an alternative to the conventional resin-based compounds used in boat building. Ideas for the project legacy continue to evolve but the way the boat has been designed it makes it possible for the whole thing to be recycled without pollution or waste: the bottles can be up-cycled into fleeces, the SrPET could be turned into another boat, the systems can be redeployed and the sailing equipment re-used.
Check out the full sized image at Plastiki
David's determination for the project to be about solutions rather than just highlighting problems has resulted in a range of inspiring closed loop design examples. This shows that, with the right attitude, it is possible to design out waste and to rethink the way we use resources to create far more intelligent solutions. There are two profound shifts we need to make: from linear to closed loop design and from a carbon economy to a solar economy. Biomimicry has, and will continue to provide many of the solutions that we need and with projects like the Plastiki Expedition we can bring about positive change. I'm proud to have played a part in making it a reality.
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More on the Plastiki
Plastiki Ship Makes its Way Across the Pacific
David De Rothschild and Crew Unveil the Finished Plastiki
David de Rothschild on The True Cost of Plastic