OUR CITIES HOLD THE KEY TO GLOBAL
ECOLOGICAL SUSTAINABILITY
They are the source of more than 70 per cent
of carbon dioxide emissions, and depending on how we develop and manage our
urban infrastructures during the next three decades. To achieve the latter
result, the US$350 trillion to be spent on urban infrastructure and usage over
the next 30 years will have to be directed towards low to zero carbon
emissions, particularly in the world’s small. There are three prerequisites
for this effort:
• Cities must adopt
• Innovative financing strategies
• The latest technological advances
The Urban Challenge
Our
cities the largest contribu-tors to greenhouse gases and climate change. The world’s urban centres already account for more than 70 per
cent of CO2 emissions. In the next three decades, the global
population will continue to grow and become ever more urban. This huge
expenditure either can cause the ecological impact of our cities to become even
more pronounced or can be a tremendous opportunity to reduce that impact. Cities
around the world in developed and developing nations need to tackle climate
change directly.
Business as Usual Is a Prescription for Failure
There
is a growing consensus that the average global temperature must not rise more
than 2 degrees Celsius over pre-industrial levels if we are to avoid dangerous
climate change. To have a reasonable chance (better than 50 per cent) of
forestalling such a rise, cumulative global carbon emissions must be limited to
870 gigatons of CO2 equivalent
(GtCO2-eq)
between 2009 and 2100. The economic cost of climate control also represents a
major challenge. The Copenhagen Accord sought to address this issue by
establishing the Copenhagen Green Climate Fund, which will provide $100 billion
annually to help developing countries mitigate carbon emissions and adapt to
climate change by 2020. Our analysis shows that global urban infrastructure and
usage expenditures in dwelling and transportation for the next three decades
will exceed $350 trillion. In order to control emissions and meet the economic
and public health challenges of urban growth.
Urbanization Trends
The
ecological footprint created by these two trends is currently distributed
unevenly among regions. For example, the ecological footprint of the average
Tanzanian or Indian is approximately a quarter of the ecological footprint of a
European and a ninth of that of an American. Cities are already the source of more than 70 per
cent of global CO2 emissions,
and they will account for an ever-higher percentage in the coming years, as
more and more people reside in and move to cities in search of more prosperous
lifestyles.
Focusing on Small Cities
The
bulk of urban population growth will not occur in well-known and mature
megacities like Beijing, London, Los Angeles, Mexico City, and Mumbai. By 2020,
its population is expected to exceed 500,000.
They
generally follow predictable patterns in the mix of expenditures and emissions
related to infrastructure development and usage. During the early stages of city
development, the bulk of expenditures and emissions stems from construction of
buildings, public transportation, and utility infrastructure, such as energy
and water. As the maturation process continues, ongoing energy usage increases
as the city grows in extent (and, not entirely coincidentally, in wealth) until
the bulk of expenditures and emissions comes from the use of existing
infrastructure. The fact that growth is occurring fastest in small cities
that are still in the process of developing their infrastructure creates a
valuable opportunity to decouple the global urban future from expensive,
high-carbon lifestyles.
Focusing
on Developing Nations
Energy
usage in residential and commercial buildings in some industrial regions, in
developing economies will be high overall compared to usage. This suggests that
there is a window of opportunity to drive down emissions. Given the rate of
urban growth in developing nations and the early stage of their infrastructure
development efforts, it is clear that they can offer the highest returns in the
quest for urban sustainability, even if they are currently less equipped to
deal with the challenge. And given the outsized energy usage of cities in
developed nations, it is also clear that developing nations should not adopt
their inadequate transportation systems and energy-wasting house and building
stock as a norm. Developing nations must be supported in a drive to minimize
energy use and undertake a shift to renewable energy sources that will enable
low carbon lifestyles for city dwellers. The first step in such an effort
should be long term, strategic level, low carbon action plans, supported by a
holistic national urban planning approach that enables the integration of large
mainstream investment flows rather than a project by project approach on the
sidelines of core development strategies and decisions.
The Planning Prerequisite
This decrease occurs due to a shift in the mix of
industries from energy intensive manufacturing to the lower energy requirements
of service industries. It can also occur because of the natural responses to
high population density. The most obvious example of the positive role of urban
density is transportation, one of the major components of energy and emissions
intensity. Population density also has a significant impact on emissions
associated with habitation. Denser land use is highly correlated with denser
individual housing units, which in turn lead to lower demands for heating,
cooling, and lighting, the principal uses of residential energy in the
industrialized world. The net result is that increasing urbanization,
industrialization, and wealth not only are inevitable but will generally have a
negative ecological impact. Higher population densities may have lower
emissions per capita, but their total energy usage is higher. The solution is
better planning, with high density as one of the central aspects of that
planning. With an integrated approach to urban planning that utilizes modern
technology, it is possible to achieve lower carbon emissions from transport and
buildings in any city.
The Investment Prerequisite
Nations
that are in the later stages of the urban infrastructure life cycle with high carbon
infrastructures should give high priority to large scale programs designed to
reduce the emissions that have been built into the infrastructures of their
cities. They should apply the latest technologies to mitigate carbon emissions
from their old stock and also set ambitious and challenging standards for
guiding their future investments. Decision makers, especially mayors, in
developing countries must also seize the opportunity to allocate their
financial resources in a strategic way that frees urbanites from high-cost,
high-emission infrastructures.
The Technology Prerequisite
Incremental technological improvements cannot
provide the absolute emission reductions needed given the rates at which our
cities and consumption levels are growing. The technological solutions that we
seek must offer transformational levels of improvement. We need to plan
infrastructures and use financial leverage from the enormous investments to
create zero carbon infrastructures that feature the intelligent use of
renewable energy sources. These will likely include solutions integrating
renewables like the electrification of private vehicles, public transportation
run on electricity and biogas, and the use of district cooling and heating,
LED, and natural lighting in buildings.
The
Low-Carbon City Is Already Emerging
As
in many cities in developing nations, emissions levels are rising in the
Chinese city of Baoding, but unlike with other cities, a share of Baoding’s
emissions growth is caused by fuelling its workforce and the machinery it is
developing to provide lowcarbon solutions to the rest of the world. Solar
photovoltaics, wind power, and energy efficiency industries have been a major
source of Bao-ding’s green growth engine for the past five years, and the city
is determined to expand further. Nationally recognised as the “Green Electric
Valley of China,” Baoding has seen the number of its green energy companies
expand from 64 in 2005 to 200 in 2008, and its green revenues have more than
quadrupled in the same period, from $700 million to $3.5 billion.