Zero-carbon city
A zero-carbon city runs entirely on renewable energy; it has no carbon footprint and will in this respect not cause harm to the planet. Most cities throughout the world produce energy by burning coal, oil and gas, unintentionally emitting carbon. Almost every activity humans do involves burning one of these fossil fuels. To become a zero-carbon city, an established modern city must collectively reduce emissions of greenhouse gases to zero and all practices that emit greenhouse gases must cease. Also, renewable energy must supersede other non-renewable energy sources and become the sole source of  energy, so a zero-carbon city is a renewable-energy-economy city. This transition which includes decarbonising electricity (increasing the importance of the sources of renewable electricity) and zero-emission transport, is undertaken as a response to climate change. Zero-carbon cities maintain optimal living conditions and economic development while eliminating environmental impact. Instead of using established cities, many developers are starting from scratch in order to create a zero-carbon city. This way they can make sure every aspect of a city contributes to it being carbon-free. Cities aspiring to be carbon-free. There are two places that  are prototyped to become zero-carbon cities: Masdar City, United Arab Emirates and Dongtan, China. Some existing cities are moving towards becoming low or zero carbon. Over the last decade, Shanghai, China has implemented dozens of low carbon policies to reduce energy usage and address the effects of climate change. The government of Melbourne, Australia launched an initiative in 2020 for the city to reach net zero emissions by 2050. In 2012 Copenhagen, Denmark created the CPH2025 Climate Plan and aims to become the first carbon-neutral capital by 2025 and for Denmark to be entirely carbon-neutral by 2050 . Malacca also has a stated ambition to become a carbon-free city, with a Low Carbon Cities programme being piloted in Malaysia as of 2014. The Low Carbon City (LCC) is a model of sustainability that promotes sustainable practices, such as reducing CO2 emissions, in existing cities. Many of the cities shifting towards a Low Carbon Model (often referred to as transition experiments) have five key focus areas: Energy, Buildings, Transportation, Industrial, and others. Launched in 2012, the Shenzhen International Low Carbon City is a national project in China. As China undergoes rapid urbanization, the Chinese government has implemented several  policies to mitigate the environmental effects of industry, redevelopment, and infrastructure construction. The project is still its first of three phases. The Development Phase is finance and investment-based. Once created, these cities will become living examples of sustainable development, which demonstrate optimal resource utilization. Once created these cities will become living examples of sustainable development, which demonstrate optimal resource utilization. Masdar City. The Masdar Initiative is an environmental urban ambition by Foster + Partners to develop a sustainable city where residents would enjoy a carbon and waste-free environment. The project is based on the principles of an ancient  walled city, combined with modern alternative energy technologies. Critics say that the city concept appears cold and uninviting, however, this project "promises to question conventional urban wisdom at a fundamental level". Masdar promises to set new benchmarks for the sustainable city of the future." The city will be entirely self-sustaining Masdar CEO, Sultan Ahmed Al Jaber explained, "... we are creating a synergetic environment; it is a true alternative energy cluster. Here you will find researchers, students, scientists, business investment professionals, and policy makers all within the same community. It will be a living example of sustainable development that will  position Abu Dhabi and Masdar at the forefront of intelligent resource utilization. It will combine the talent, expertise and resources to enable the technological breakthroughs necessary for truly sustainable development." Construction of this large-scale project will occur in two phases. In phase one, a solar photovoltaic power plant will be built as a central energy source. In phase two, urban growth will occur. The site is located in close proximity to Abu Dhabi's transportation infrastructure, which will allow for easy access to and from surrounding communities. An efficient network of rail, road and public transit will link the  city to central Abu Dhabi and the international airport. Dongtan. Dongtan, China was a sustainable eco-city project planned in the 2000s that was never built. Reasons for the project's failure include confusion over who would fund Dongtan (Arup, its British engineering company, or Shanghai Industrial Investment, its state-owned developer) as well as the jailing of Dongtan's top political backer, former Shanghai Communist Party chief Chen Liangyu, on corruption charges in 2008. Dongtan was to be located at the east end of Chongming, adjacent to the Chongming Dongtan National Nature Reserve. Seeing as this area is near  wetlands, some questioned its potential effects on the surrounding environment. The director of the project, Peter Head, insisted it would not affect the wetlands. The developers planned on a fully built city, with 80,000 residents by 2020. Adjacent to booming Shanghai, designers claimed Dongtan would be the world's first truly sustainable new urban development. London-based Arup and the Shanghai Industrial Investment Corporation (SIIC), the city's investment branch, originally partnered to create a master plan for Dongtan, an area three quarters the size of Manhattan. Their brief called for integrated sustainable urban planning and design to create a  city as close to carbon-neutral as possible within economic constraints. Located in sensitive wetlands on Chongming Island at the mouth of the Yangtze River just north of Shanghai, Dongtan's first phase, a marina village of 20,000 inhabitants, was supposed to be unveiled at the 2010 World Expo in Shanghai, however this never occurred. By 2020, nearly 80,000 people were expected to inhabit the Dongtan. As a strategic partner, Arup was to be responsible for a range of services, including urban design, sustainable energy management, waste management, renewable energy process implementation, architecture, infrastructure, and even the planning of communities  and social structures. Peter Head, director of Arup's sustainable urban design, led the project for the firm from its London's office (during design, Arup claims to have offset the emissions of its team's travel to and from the site in cooperation with emissions brokerage firm CO2e). "Renewable energy will be used to reduce particulate CO2 emissions. Transport vehicles will run on batteries or hydrogen-fuel cells and not use any diesel or petrol, creating a relatively quiet city," according to Head's original plan. Other priorities included recycling organic waste to reduce landfills and generate clean energy . Head insisted development wouldn't affect the wetlands. "First of all, water usually discharged into the river will be collected, treated, and recycled within the city boundaries," he said. "There will be a 2-mile buffer zone of eco-farm between city development and the wetlands." While farming is water intensive, relatively small amounts of water reach the plants themselves. Head said Dongtan "will capture and recycle water in the city and use recycled water to grow green vegetables hydroponically. This makes the whole water cycle much more efficient". Dongtan was expected to eventually be home to more than 500,000  residents, which is an insignificant number for a country of 1.3 billion people, but the failed carbon-neutral experiment of Dongtan was meant to be a model for development worldwide. Initiatives. Transport. Cars will be banned within the city, instead battery-powered and auto piloted personal rapid transit systems (PRT) will be used Visitors to the city must park their cars outside and use public transit. In both prototypes there will be ideal conditions to encourage walking or cycling. Additionally, both Masdar City and Dongtan will be connected to their larger counterparts via rail or road. Energy. Eco-cities are  self-sufficient in energy. They meet energy need through solar, wind and biomass sources. About 80% of energy will be solar energy, it will be generated through photovoltaic panels, concentrated solar collectors, and solar thermal tubes. In order to keep cooling costs down wind cooling towers and narrow streets will be put in, these help to maximize shaded areas. Planners in Dongtan are putting meters in each house to display energy use. Guiding principles. There are 10 principles that are proposed to create an eco-city. The developers of Dongtan have used them in order to create a carbon-free  city.