Press release
Alstom and Carbone 4 compared the carbon footprints of trams and high-level-of-service buses
Alstom and Carbone 4 compared the carbon footprints of trams and high-level-of-service buses
November 4, 2016 – Alstom and Carbone 4, a leading consulting firm specializing in low-carbon and climate-resilient strategies, today unveiled the results of a study showing that tram systems have a smaller carbon footprint than Bus Rapid Transit (BRT) systems. These findings were released ahead of COP22, which will take place in Marrakesh, Morocco, and in which Alstom will participate.
Given that global emissions from urban transportation are projected to double and reach nearly 1 billion metric tons of CO2 equivalent per year by 2025, it is crucial to promote modes of transportation with the lowest carbon footprint. Rail transport can play a key role in the effort to reduce greenhouse gas (GHG) emissions and achieve the 2°C target set at the 2015 COP21.
Trams, for example, have been identified as one of the most environmentally friendly modes¹ of urban transportation, given their low environmental impact. The study conducted by Alstom and Carbone 4 compares the carbon footprints of trams and BRT systems, providing a better understanding of their respective performance throughout their entire life cycle, including the construction, operation, and maintenance of both systems. An analysis of a conventional 10-km line in Belgium shows that, for equivalent transport capacity over a 30-year life cycle, a tram system emits roughly half as much CO2 as a BRT system operating with diesel buses, and about 30% less CO2 than a BRT system operating with hybrid buses.
Julien Blanc, Associate Director at Carbone 4, said: “ Reducing greenhouse gas emissions in the transportation sector is both a major issue and an interesting challenge. This goal should be achieved through effective urban planning, energy efficiency, clean energy, and, of course, modal shift. Trams are, of course, part of the solution, and this infrastructure will benefit from all the improvements associated with “cleaning up” the electricity mix. "
According to Cécile Texier, Alstom’s Director of Sustainable Development: “ We are constantly working to promote sustainable mobility, doing everything we can to reduce our customers’ energy-related operating costs, and committed to reducing the carbon footprint of transportation. The study, conducted in collaboration with Carbone 4, shows that rail systems have a lower carbon footprint compared to other motorized modes of transportation. It also shows that an optimized system like Attractis—an innovative integrated tram system that is easier to operate and has an optimized total cost of ownership—2", can significantly reduce CO2 emissions starting with the construction phase."
Alstom helps raise awareness of transportation-related issues and promote sustainable transportation in international climate change negotiations by supporting the Paris Process on Mobility and Climate (PPMC). Alstom will participate in the PPMC’s Transportation Day on November 13 during COP22 in Morocco, where its Citadis trams have been in service in Casablanca and Rabat since 2011. In Rabat, nearly 120,000 people ride the tram every day; given this tremendous success, the city has decided to expand the network. Studies³ indicate that two tram lines could reduce CO₂ emissions by nearly 30,000 metric tons per year.
To learn more about Alstom's commitments to sustainable mobility and read the report summary, click here
About Alstom
As a champion of sustainable mobility, Alstom designs and provides systems, equipment, and services for the rail sector. Alstom offers the broadest range of solutions on the market—from high-speed trains to metros and trams—along with customized services (maintenance, modernization, etc.) and infrastructure and signaling solutions. Alstom is a global leader in integrated rail systems. In 2015/16, the company generated revenue of 6.9 billion euros and received orders totaling 10.6 billion euros. Alstom, headquartered in France, operates in more than 60 countries and currently employs 31,000 people.www.alstom.com
Alstom Press Contacts Linda Huguet – Tel. +33 1 57 06 10 42 linda.huguet@alstom.com
Justine Rohée – Tel. +33 1 57 06 18 81 justine.rohee@alstom.com
About Carbone 4
Founded by Alain Grandjean and Jean-Marc Jancovici, Carbone 4 is an independent consulting firm specializing in energy transition, which offers its expertise to public and private sector organizations. Through the 600 projects it has already completed in France and internationally, Carbone 4 has developed several innovative analytical methods and nearly a dozen sector-specific methods for calculating carbon footprints. Convinced that proactively addressing carbon constraints is the best possible approach, Carbone 4 works with its clients to help them transform these constraints into a powerful driver of innovation, a key competitive advantage, and a source of motivation for their teams.
Carbone 4 Press Contact Dorothée Coloby - Tel: +33 (0)1 76 21 10 00 dorothee.coloby@carbone4.com
1 Excluding bicycles
2 Thanks to optimized project management and construction methods, Attractis is available in record time—just 30 months after the design phase.
3 Source: CODATU/French Development Agency (AFD)


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