Developing a Sustainable Eco-City in Pre-Olympic Tokyo: Potential of New Methods and Their Limits in an Urban Era

Environmental Problems in the Urban Era: Overinvestment, Overpopulation, Overshoot

The concepts of “city” and “nature” are perceived as intrinsically contradictory, and authors who stand for the latter have criticized cities for their negligence of and dominance over the environment. Moreover, on a global scale, the concentration of populations in urban areas is growing. It is estimated that in 2030 more than 60% of the world’s population will live in cities, and 27% will reside in cities with at least 1 million inhabitants (UN Habitat, 2016). The agglomeration of gross domestic product (GDP) in cities escalates accordingly and 80% of the world’s total GDP is concentrated in urban areas. Paris, for instance, houses only 16% of the French population but produces about 27% of France’s GDP (UN Habitat, 2016, p. 27). This condition is known as the ‘overdevelopment, overpopulation, overshoot’ issue, suggesting the excessive burden to the natural environment caused by urbanization (Butler, 2015). The United Nations has therefore adopted a new 2030 Agenda for Sustainable Development, which presents 17 goals that replace the previous Millennium Development Goals (United Nations, 2016, pp. 38-39). This agenda includes several new elements, such as making cities and human settlements inclusive, safe, resilient, and sustainable. Furthermore, it demands the development of low-carbon societies and green technology or the replacement of conventional energy resources with renewable energy, especially in cities, which represent more than 70% of the global energy demand.