Four of the world’s largest bus and engine manufacturers have committed on Sept. 27 to make it easier for major cities to purchase buses equipped with low emissions technologies, in order to tackle climate change and toxic air pollution. BYD, Cummins, Scania and Volvo Buses will ensure ‘soot-free’ engine technology is available for purchase in 20 megacities beginning in 2018.

BYD, Cummins, Scania and Volvo Buses have agreed to work with cities to adopt bus fleets equipped with the latest in clean power technologies to tackle climate change and air pollution.

The manufacturers will each release a full product portfolio available in each city and will begin publicly reporting the number of soot-free buses sold in each year.

Soot-free is defined as including any engine that meets Euro VI norms first established in Europe or EPA 2010 norms first established in the United States, and any diesel engine with a diesel particulate filter, gas-powered engine, or a dedicated electric drive engine.

Further reductions in climate impacts of soot-free buses are achievable with low-carbon fuels and engines that deliver the lowest lifecycle greenhouse gas emissions.“Air pollution is the leading environmental health risk today affecting millions of people, particularly those in our growing cities,” said Erik Solheim, executive director of the United Nations Environment Program. “This agreement between some of the world’s leading bus manufacturers and some of the biggest cities in the world is an example of forward-thinking private and public cooperation. “Investment in technology, products, and business models that benefits people and our environment isn’t just good for the planet, it’s good for business.”

The cities involved in the scheme are, Abidjan, Accra, Addis Ababa, Bangkok, Bogotá, Buenos Aires, Casablanca, Dar es Salaam, Dhaka, Istanbul, Jakarta, Johannesburg, Lagos, Lima, Manila, Mexico City, Nairobi, Santiago, Sao Paulo, and Sydney.

Less than 20% of all buses sold globally meet the definition of soot-free, with the vast majority being diesel powered. Older generation diesel technology produces high levels of black carbon emissions, or soot, which are amongst the most dangerous pollutants for public health and a major contributor to climate change. The cleanest buses today can reduce these emissions by more than 99 percent.

The Global Industry Partnership on Soot-Free Clean Bus Fleets is an initiative led by C40 Cities, the Climate and Clean Air Coalition (CCAC), and International Council on Clean Transportation (ICCT), Centro Mario Molina Chile and UN Environment. The commitment was announced at the CCAC Clean Buses for Clean Air Workshop in Paris.