A new article that outlines how circular economy principles can be used to plan and design new villages in regional areas has been put forward by Dr Steven Liaros, from the Department of Political Economy at The University of Sydney.
Recently published on www.urbandesignreview.com, Dr Liaros says managing food, water, energy, housing, and transport as a unified infrastructure ecosystem ‘makes all of them more efficient’.
He describes three generally agreed principles that characterise a circular economy: ‘eliminate waste and pollution, circulate products and resources; and regenerate nature’.
Dr Liaros writes, ‘Developed by the Ellen Macarthur Foundation, these principles are “Underpinned by a transition to renewable energy… [such that] the circular economy is a resilient system that is good for business, people, and the environment.’
The design process in practice
‘This all sounds good in theory, but how do we go about the design process in practice? He says the usual approach when planning a greenfield development (i.e. a suburb) on a parcel of land is to ‘ask how many houses can fit on it’.
‘Instead, we propose to start by saying we want to house a certain population, say 200 people. Then we can ask questions like: How much land is needed to sustain 200 people?
How can we enhance the capacity of this land, so that it provides other natural needs such as food and water? How can we keep resources circulating so that the community can minimise the need to buy in new resources? Where do we locate the housing so that it can be passively designed to minimise energy demand? What other indoor and outdoor spaces and facilities would improve the quality of life of the residents? How do we arrange the various buildings and supporting infrastructure to maximise the efficiency of the village as a whole?
‘The answers to some of these questions will depend on the climate, geography, and existing ecosystems of the land, and so each village must be designed for its location.
To simplify, let’s imagine a generic parcel of rural land, say 40 hectares, or 100 acres, in a regional area adjoining an existing town or village. As the circular economy is underpinned by renewable energy, a good place to start is to design the village as a resilient system powered by a renewable energy micro-grid.
As we can estimate the energy needs of a population of 200, it’s possible to estimate the scale of generation and storage systems, not just for housing, but also to power a fleet of shared electric vehicles, including golf carts and bikes for movement within the village.
What other resources do we want to circulate
‘What other resources do we want to circulate in the village system? What about water? Again, we can estimate how much water is needed for 200 people. A chain of ponds along a gully could store rainwater or bore water for use by residents. This could also be used for irrigation of food production.
The lowest reservoir can be designed as a constructed wetland to clean grey water before the water is pumped, using renewable energy, back up to the topmost reservoir, reusing water again and again, and thus creating a managed water cycle. Reservoirs can have multiple functions in addition to storing water, they also offer opportunities for swimming, recreation, and aquaculture.
‘With an abundance of water, it is possible to produce more food, taking urban agriculture to a new level. Indeed, enabling the development of a comprehensive regenerative agricultural system will not only produce food for residents but will help regenerate nature, one of the three principles we are striving to implement in the design.
There are numerous approaches to regenerative agriculture, also called agro-ecology, but, according to Charles Massy, all seek to maximise biodiversity and then harvest, store, and circulate energy, water, and nutrients – aligning precisely with the design approach for circular economy villages.
A unified infrastructure ecosystem
‘Rather than managing each one separately, food, water, energy, housing, and transport are now parts of a unified infrastructure ecosystem. The integration of these infrastructure systems makes all of them more efficient.
Food waste can be composted or used to make heat and biofuels for energy, water reservoirs can also store energy, passively designed housing can minimise energy demand. A walkable environment with multiple work, education, and entertainment activities, close to housing, reduces transport needs, while improving the health of residents.
‘Each such village should be perceived as a node in a network of villages. As Figure 1 shows, Ebenezer Howard argued over a century ago that the “correct principle for a city’s growth” is to build a network of garden cities rather than sprawling the central city. Howard proposed self-contained, satellite cities with a population of 32,000 on 9,000 acres, linked by road and rail to a major centre reflecting the mechanistic thinking of his time.
What might a garden city of the 21st century look like? The technologies and business models available today allow new settlements to be both more connected virtually, while being more self-contained in the physical world, affecting both the design of individual settlements and the organisation of a network of settlements’.
