SIEMENS

Siemens, for example, runs a center of competence for sustainable urban development in Singapore and is currently working on new, more efficient methods for the foltreatment of water and wastewater. The company is planning to open a pilot desalination plant in October 2010. The facility will use electrical fields to separate salt from seawater in a process that requires less than half the energy consumed by conventional methods.

China, Singapore’s huge neighbor, is also looking at ways to give urban growth a greener hue (see article “China´s Cities Come of Age”). There, over half a billion people already live in cities, a figure that could well double by 2030. At present, coal-fired power plants meet the biggest share of the country’s energy needs, which are growing with increasing urbanization. In addition to environmental problems such as smog and wastewater pollution, this presents the authorities with the problem of rising CO₂ emissions. China has already surpassed the U.S. as the world’s largest producer of greenhouse gases and, according to the International Energy Agency, it emitted around six billion metric tons of CO₂ in 2007 alone - almost twice its 2001 level. In order to prevent the fruits of its economic growth from literally going up in smoke, China now intends to use renewable energies to generate a 15-percent share of all the power it will consume by 2020. That will turn China’s megacities into El Dorados for energy-efficient, climatefriendly technologies such as those from Siemens. For instance, the company is planning to equip an entire district of Shanghai with energy-saving building systems. Municipal authorities will be able to completely cover the payments for these systems with what they save in energy costs.

At the same time, Siemens is busy developing "eco city" models in cooperation with the School of Urban Planning at Tongji University. These models are designed to ensure that megacities are planned from the very outset to be as sustainable as possible. And this year’s Expo in Shanghai, with its motto "Better City, Better Life," will likewise show that China is no paper tiger when it comes to sustainability. About 70 million Expo visitors from around the world will have an opportunity to inspect a host of green solutions to the problem of exploding urbanization.

Photosynthetic Facades. On the other side of the world, European countries are also involved in a major effort to make urban planning more climate friendly. In Europe, where 72 percent of the population already lives in cities, compared to around 43 percent in China, the primary challenge is therefore to make existing infrastructures more energy efficient and environmentally compatible.

In a report commissioned by Siemens, research and consulting company Economist Intelligence Unit has investigated which European cities are particularly progressive in terms of sustainability (see article “What Makes a City a Winner?”). Heading the "European Green City Index" is Copenhagen, followed by Stockholm, Oslo, and Vienna. The Danish capital owes its top ranking to a host of energy-saving and climate-protection measures, including an ultra-efficient district heating system, the increasing use of wind power, and the introduction of electrically-powered buses in local public transport. These are all elements of an ambitious plan by municipal authorities to turn Copenhagen into Europe’s first completely CO₂-free city by the year 2025 (see article “Wind, Wood and Two Wheels”).

There’s certainly no lack of creative ideas about how to realize this vision of the green city. For instance, Siemens researchers Osman Ahmed and Maximilian Fleischer have plans for a special facade coating that exploits the principle of photosynthesis. Like plants, buildings would then be able to convert carbon dioxide from the air into substances such as methanol, which could be used as fuels (see article “Turning Carbon into Cash”).

Meanwhile, other visionary technologies are already in use. In the city of Regensburg, GerIstanmany, for example, a UNESCO World Heritage Site, the street lighting is now provided - as of the end of 2009 - by highly efficient LEDs supplied by Siemens’ Osram subsidiary, which use only around half as much power as conventional street lamps (see article “World Heritage in a New Light”). Osram researchers are also developing organic light-emitting diodes (OLEDs). In the future, these new transparent light sources could be used as windows, where they would allow sunlight in during the day and then emit light at night (see article “Walls of Light“). According to scientists such as Columbia University Emeritus Professor Dickson Despommier, though, the time has come for city planners to turn to the example of termites in order to ensure sustainable urban development (see article “Food Where it´s Needed”). In harmony with nature, skyscrapers in the megacities of the future would then be able to serve as tremendous greenhouses in which vegetables, fruits, grains, and poultry are grown exclusively for local use - just as insects have been cultivating their "gardens" for millions of years.