Inverse Functions, Reversing Trends in Urban Living
Imagining the future Africa. Inside ‘Africa: Big Chance Big Change” Trienalle di Milano. Milan, Italy.
Curated by Benno Albrecht. 2014
Human life, an integral part of the planet earth will not threaten others that inhabit the planet. Compared to a century ago we are now using 10 times as much energy as we did to sustain our Current lifestyle is using significantly more resources than a century ago, and is expected to increase dramatically due to rapid urbanisation of developed countries if the trend continues. New urbanisation models are urgent, which imply a complete reversal of urban living trends, manage natural resources judiciously, and reduce pollution of water, air and soil, while providing a higher quality of collective life based on knowledge and collective responsibility.
The African continent, being still a largely untamed virgin territory, at the brink of major urban development is an opportunity to illustrate models of urban living for future human settlements, to reset trends and redefine the meaning of ‘development’ for today and tomorrow, not only for itself but for the rest of the world. The shortage of resources coupled together with the abundance of current knowledge and consciousness makes Africa a fertile ground to demonstrate achieving the most with the least; building urban life without compromising the continued sustenance of the other species of flora and fauna that inhabit the land; creating new models of water, energy and waste management carefully negotiating the degree of centralised and decentralised systems.
Technologies used negotiate the degree of high-tech or low-tech, between hand-made and machine made, achieve models of affordable habitat relevant for future cities anywhere in the world where affordability is a growing concern, not only in economic terms but also environmental terms.
The proposed city with a population of 150,000 occupying around 5km diameter and 20 km2 area, is a prototype for the several small-scale cities that can be plugged on to the railway network that is currently being reinforced, in places where solar and wind energy are easy to tap. The idea of efficient public transport over private transport will continue thus, right into the city while strengthening the intercity connections.
The key areas of repositioning and inversions are as follows:
- Leaving the Ground to Nature: The original ground beneath the city continues to breathe, not sealed off by cement and concrete of buildings which contact the ground in limited places. Air and cleansed rain water can penetrate the earth naturally recognising the earth as alive which remains available to vegetation including food. Urban parks and gardens that are habitually seen as patchwork between buildings, is reversed in their significance by arranging them in continuity from the nature surrounding the city penetrating to its very centre, like a continuous network of arteries and veins, circulating oxygen throughout the cells of the city, enlarging in places to support recreation and other green activities. The city centre is a central park, the central services located further back to avoid congestion. The morphology springs from original plots retaining memory and historical record placing this ancient information at the foundation and creating out of the same, a new tissue of habitat.
- Reclaiming roofs as public space: Areas of concentration and mobility are located above the high-density structures sparing the ground surface of the impact. Softer paths of mobility that occur on ground level are limited to low-impact movement of pedestrians, bicycles and occasional non-polluting service vehicles. This means that the people are at the top, symbolising the bottom-up approach to future city-living, empowering democracy and public participation.
- Floating living spaces between open sky and free ground: Spaces are crafted with passive building strategies to reduce the demand for energy for artificially cooling or heating. The bulk of the structures use local building materials with low embodied energy, involving local skills and public participation, allowing incremental growth according to means, strengthening identity and engagement. High-tech is restricted to the main spine and specialised areas where space efficiency justifies the use of materials with higher embodied energy.
- Concentrating services along 3 spines: In order to enable the bulk of the city to be produced through low-tech means and without highly sophisticated skills, the main urban tissue has low density typologies. In stark contrast, three linear arrangements concentrate sophisticated buildings for high density housing and office spaces requiring such infrastructure.
- Green network of mobility: Predominantly a pedestrian and bicycle city, the triangular spine carries straight-forward connections from the railway station, for public transport as well as bicycles, and the main distribution lines for other infrastructure. Every other place can be reached within 10 minutes of walk from this spine. The spine that does not intersect the railway station is the only route where automobiles circulate within the city. Economic activities and those needing access to motorised vehicles are placed along this spine. All plots are served through a pedestrian/bicycle network on one side and are connected to the green network on the other.
- Reversing the Tower: High rise buildings are along the 3 spines of hi-tech infrastructure. Given the roof occupation as public space and the sloping terrain, the vertigo effect of high rise buildings towering above is reversed. Instead the public space allows a view of a valley containing the central park flanked on either side by the row of sophisticated buildings whose height is inversely revealed as the city slopes down along it.
- Managing water through diverse sources: Ground water is significantly reduced and used mostly for cooking, and drinking. Rain water from roofs is harvested as decentralised arrangements, for cleaning and bathing, while storm water from ground surfaces is collected centrally and pumped to overhead tanks for flushing toilets. Treated waste water is used in several cycles and finally supplied for irrigation through out the city.
- Providing energy through hybrid systems: Passive strategies, appropriate building technologies, pedestrian mobility and concentration of principal services significantly reduce the energy demand of the city. The thus reduced energy demand is met to a great extent by renewable energies: solar photovoltaics on rooftops, solar thermal systems for hot water, wind and biomass.