By Matthew Plumbridge
Reversing climate change, one city at a time.
The world is currently immersed in an Ecological Age; a time where society and industry are focusing on solutions to reverse climate change. Most developed countries have undergone stages of development, namely, the Agricultural Age, the Industrial Age, the Services Age, and most recently the Information and Communication Age.
For these countries, the Ecological Age presents enormous challenges in terms of integrating principles of sustainable resource consumption. To date, society's inefficient use of natural resources has created huge pressure on natural systems and has, in some cases, lead to a total systems collapse.
In other parts of the world-China, India and parts of the Middle East-the Ecological Age is happening in parallel with the main development phases. Major economic development, occurring in parallel with a growing environmental consciousness, presents enormous challenges and opportunities for the integration of sustainability and economic growth.
Development in these parts of the world is often characterized by rapid urbanisation. In fact, according to a 2005 UN study on urbanisation, the world's urban population increased from 13% in 1900 to 29% in 1950 to 49% in 2005. At this rate, 60% of the global population is expected to live in urban areas by 2030.
According to a separate UN statement, "Most cities [in developing countries] already have pressing concerns, including crime, lack of clean water and sanitation and sprawling slums. But these problems pale in comparison with those that could be raised by future growth...If we do not plan ahead it will be a catastrophe."
For places like China, India and the Middle East, the pace and scale of development is giving developers only one chance to shape the way millions, and possibly billions, of people will live their lives.
Adapting to climate change
Prior to the intense level of development on the Arabian Peninsula, people adapted to harsh climates by using traditional methods to harness wind, water, materials and shade.
Until the advent of air conditioning, cities and buildings were designed with a total systems approach in mind. They optimised breeze, shade, architectural orientation, thermal mass and heat reflection.
Sustainability is embedded in the history of the local culture. At a recent conference in Australia, Al Gore spoke of the leadership that exists in Dubai. Therefore it is not unreasonable to expect that global solutions will be generated from a culture with visionary leadership.
Waterfront as an example
For example, Nakheel's Waterfront, is an example of how Dubai is both responding to the challenges of the Ecological Age and leading the way in developing innovative sustainable solutions.
With plans to accommodate an estimated 1.7 million people in an area of 120km2, Waterfront is set to become a true eco-city. It will serve as an exemplar for urban development in harsh climates, and will set the benchmark for urban development across the planet.
In order to maximise efficiency in design, every design decision on Waterfront is informed by critical data generated from first principles. This allows designers to optimise everything, from the type of product or the size and scale of utilities, to the life cycle costs and benefits of every component of the city.
The Waterfront sustainability team is undertaking an energy strategy that looks at every aspect of the city's energy consumption, with the aim of delivering a low carbon city. To that end, reducing the demand for energy as well as supplying alternative or renewable sources of energy is crucial.
Alternative ways to reduce energy
Traditionally, energy demand is reduced in buildings through good design practices; concentrating on the thermal performance of materials; and considering orientation and proportion of glazing to wall area.
Absorption chillers are another way of meeting air conditioning requirements of buildings. Also, capturing heat from the atmosphere through solar thermal collectors could provide a portion of the energy required to generate cool air.
Examining infrastructure and utilities in an integrated manner identifies opportunities to maximise the use of resources.
Moreover, leftover heat from a Combined Heat and Power (CHP) plant can be used to produce potable water in the desalination process or to provide the heat required to power absorption chillers.
Water requirements in district cooling can be reduced by controlling the demand for cool air in buildings. Wastewater can be treated and used for irrigation, while sewage sludge can be used as a feedstock in waste-to-energy processes.
Energy can also be generated from municipal waste through anaerobic digestion and gasification technologies which are being applied in the region's buildings.
Long term urban planning solutions
Car-based transportation is a major consumer of energy. The overall layout and make up of a city is a key determinant in the length of trips generated. Urban planning should aim to reduce the length of trips taken and to facilitate a significant proportion of these trips to be undertaken by public transport.
Not only is energy consumption reduced, transport-related environmental impacts such as air and noise pollution are reduced, creating a more pleasant urban environment and ultimately a more liveable city.
Further improvements to energy related transport consumption can be made through adopting policy measures to reduce private vehicle-based trips, such as congestion charging, designation of low emission zones, and use of consolidation centres to manage the efficient distribution of freight.
While public debate on energy often focuses on high-profile renewable energy supply options, the reality is that reductions in energy demand are the most important part of a long term sustainable energy strategy.
Energy demand reduction targets have been set for buildings, infrastructure and transport following detailed analysis of the feasibility of achieving these targets in Nakheel's Waterfront. Its sustainability team is currently working on measures to implement targets into the design and procurement processes and the systems for managing and operating the city.
Reduction targets have been benchmarked against international practices, and once implemented, will ensure that the city is a leading example of a large-scale low-carbon development.
From energy demand to energy supply
While Dubai is frequently mentioned as an ideal location for generating energy from solar resources, the challenge lies in matching solar energy sources to the period in the day when it is most needed according to energy demand.
In the absence of proven large-scale energy storage technologies, solar energy generated during sunlight hours will be unable to meet the high energy demand in the evening, and can therefore only represent one part of the overall energy solution.
A successful low carbon city requires strong and sophisticated governance. While Dubai has consistently demonstrated strong and visionary governance including H.H. Sheikh Mohammed bin Rashid al Maktoum's mandate for sustainable design in all future buildings, claims of cities powered 100% by solar energy should be treated with caution.
Requiring strong governance to achieve sustainable outcomes is a theme reflected in the plans for Waterfront. Systems are being put in place to monitor and collect data on the sustainability performance of the city during its operational lifetime.
Real-time information will be fed to inhabitants, which will create a living entity that continually optimises its sustainability performance. This will give people the information necessary to modify their own behaviour in relation to resource consumption-a key component of a sustainable city.
Waterfront is one example of how Dubai is leading the response to current global environmental challenges. At a time when other nations are prevaricating over how to best deal with global environmental issues, Dubai is rapidly implementing plans to realise the vision of an ecological city for 1.7 million people.