Changing Planet

C40 announces ground-breaking research in low emissions transport

The C40 Cities Climate Leadership Group (C40) today unveiled a new report on the use of low carbon bus technologies in Latin American cities, the findings of which could help shape the next generation of sustainable urban transport in the region and beyond.

C40 Chair and New York City Mayor Michael R. Bloomberg announced the results of the Hybrid Electric Bus Test Program — an initiative designed and implemented by C40 in partnership with the Clinton Climate Initiative, and with financial support from the Inter-American Development Bank (IDB) — during the New York Times Building Sustainable Cities conference.

Through the participation of local governments, bus suppliers, and bus operators, the Program measured the emissions from, and evaluated the technological performance of, hybrid and electric buses in Bogota, Rio de Janeiro, Sao Paulo, and Santiago de Chile.

Some of the Program’s key outcomes include:

  • Hybrid and electric technologies produce smaller volumes of GHG emissions and local air pollutants and are more fuel-efficient than standard diesel buses.
  • By reducing harmful local pollutants and other externalities (such as noise pollution), adopting hybrid and/or electric bus technologies brings significant environmental and social benefits.
  • Hybrid and electric technologies are cheaper in the long run. In spite of the higher initial purchase costs of low carbon buses, the total life cycle costs (calculated over a 10 year period of assumed operation) is equal to and in many cases lower than the cost of conventional diesel buses.

Bloomberg Nyt Building Sustainable Cities Conf

The report featured remarks from Mayor Bloomberg, President Bill Clinton, and IDB President Luis Alberto Moreno:

“The transportation sector has a significant impact on rising greenhouse gas emissions levels, so shifting vehicles to cleaner energy sources remains a vitally important challenge. In New York City, we have increased the size of our electric vehicle fleet and made our yellow taxicab fleet more fuel efficient, and this year we will begin a pilot program to place electric vehicle charging stations around the city. Cities across Latin America have also been working to improve their transport systems to achieve better air quality, and this report can provide a roadmap for cities around the world to help achieve similar outcomes.” – C40 Chair, Mayor of New York City Michael R. Bloomberg


“By making investments in low carbon transit solutions such as hybrid and electric vehicles, we are able to better address major global issues including climate change and our reliance on oil. This low carbon transit program demonstrates that clean energy technologies have the potential to significantly reduce greenhouse gas emissions in urban areas, and is a catalyst for other cities and governments that want to make long-term investments which are beneficial to both the economy and the environment.” – President Bill Clinton, founder of the Clinton Foundation


“The Bank is committed to climate change mitigation and supports sustainable transportation initiatives in the region. The Hybrid and Electric Bus Test Program demonstrates opportunities to promote clean technologies in public transportation systems, and the interest of cities in adopting them.” – Luis Alberto Moreno, President IDB

To read the full press release, click here.

To download the report, click here.

The C40 Cities Climate Leadership Group (C40) is a network of large and engaged cities from around the world committed to implementing meaningful and sustainable climate-related actions locally that will help address climate change globally. Recognizing that cities consume over two-thirds of the world’s energy and account for more than 70% of global CO2 emissions, our organization’s global field staff works with city governments, supported by our technical experts across a range of program areas to reduce carbon emissions and increase energy efficiency in large cities across the world. The current chair of the C40 is Rio de Janeiro Mayor Eduardo Paes, and 108th Mayor of New York City Michael R. Bloomberg is President of the Board. The Steering Committee includes: Berlin, Buenos Aires, Copenhagen, Hong Kong, Houston, Jakarta, Johannesburg, London, Los Angeles, Rio de Janeiro, Seoul and Tokyo.

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