Mumbai densest city, Singapore greenest: Siemens survey

08 Mar 2011

Environmental awareness and climate protection guidelines are playing an increasingly important role, a survey commissioned by Siemens has revealed.

The Asian Green City Index, which surveyed the environmental sustainability of 22 major cities in Asia, found that Singapore is the greenest metropolis in Asia.

Among the Indian cities Mumbai, Delhi, Kolkata and Bengaluru, which were surveyed, it was found:

  • Of the 22 cities, Mumbai is the densest city in the index with 27,000 people per square kilometre - more than 27 times more tightly packed than Wuhan, which has less than 1,000 people per square kilometre.
  • Kolkata benefits from a relatively low level of water consumption, at 138 litre per person per day - this is one of the best rates among the 22 cities, and better than the average of 278 litre.
  • Delhi has an extraordinarily low per capita waste generation figure of 147kg per year, which is explained through Delhi's advanced policies, including one of the more robust strategies to reduce, re-use and recycle waste.
  • Bengaluru has some of the lowest levels of CO2 emissions per capita – this is partially reflected in the fact that 30 per cent of Bengaluru's energy consumed comes from renewable energy and 61 per cent of the electricity is generated from renewable sources, mainly hydropower. The city's relatively low income, resulting in a less energy-intensive lifestyle, also plays a part in reducing CO2 emissions, as does the shift from heavy industry to IT-related businesses.  
  • There is a variation in green spaces from two square metre / person in Kolkata, to 166 square metre / person in Guangzhou.
  • Asian cities produce less waste per capita than Europe and Latin America, but waste collection is less effective. The 22 Asian cities generate an average of 380kg of waste per person per year, compared with 465kg in Latin America and 511kg in Europe.
  • The 22 Asian cities use an average of 277 litre of water per person per day, which is slightly higher than the figure for Latin America, 264 litre, but lower than the figure for Europe, at 288 litre.
  • Air pollution is a serious problem across Asia, with average levels of the three pollutants evaluated in the index exceeding the safe levels set down by the World  Health  Organisation (WHO).

''The study of Asian cities shows one thing very clearly: higher income does not necessarily mean higher resource consumption. While resource consumption increases substantially up to an annual gross domestic product (GDP) of about €15,000 per capita, it drops again when income rises beyond this,'' said Jan Friederich, research head, of the EIU study.

''In addition, cities that performed well in the index are characterised by their ability to successfully implement environmental projects and consistently enforce regulations,'' explained Friederich.

Challenges facing Asian cities:

According to the study, the biggest challenges facing Asia's cities are in the following areas:

  • Air pollution levels are relatively high in all the cities studied, regardless of income. The average values for all the cities substantially exceed WHO standards.
  • Asia's metropolises have much catching up to do in the area of renewable energies, which on average account for 11 per cent of the total electricity generated in the 22 cities. By comparison, the average in Latin America is 64 per cent – due to the high proportion of hydroelectric power plants there.
  • Increasing urbanisation is having an enormous impact on the infrastructure. The Asian Development Bank estimates that to cope with the influx, the Asian cities must for example build 20,000 new homes and 250 kilometers of road and provide transportation infrastructure and an extra six million liters of drinking water, all on a daily basis.
  • In addition, the cities are the main emitters of harmful greenhouse gases: Cities are the growth engines of the future, but they are also responsible for 75 per cent of worldwide energy consumption and for around 80 per cent of the human CO2 emissions.

''The battle against climate change will be decided in cities. This applies to Asia, with its booming conurbations, more than anywhere else on earth. Only green cities will make life worth living over the long term,'' said Barbara Kux, member of the Managing Board of Siemens AG and the company's chief sustainability officer.

The Asian Green City Index examined the environmental performance cities in eight categories: energy and CO2, land use and buildings, transport, waste, water, sanitation, air quality and environmental governance.