Gone will be the days of touring London in the iconic red double decker bus, at least in the traditional sense of what is under the hood.

At the world’s first Clean Bus Summit in London last week, 24 world cities committed to over 40,000 ultra-low emission buses rolling out by 2020. One of the most notable is conversion of central London’s fleet to completely electric double decker busses.

London originally converted from the standard bus protocol to a low emission model with diesel hybrid buses and is currently ranked as the cleanest bus fleet currently in circulation. There was always the desire to move it towards fully electric, but there was a concern about the ability of electric to handle the extra weight of the double decker bus.

After seeing the success of the power behind Chicago’s nine ton garbage trucks last fall however, the Mayor began to press for a similar conversion for the double decker buses. At the summit it was confirmed that London was partnering with Chinese electric bus manufacturer BYD.

The trial for these new buses is set to begin this fall. Hopefully as London paves the way it will be easier and more inexpensive for other cities to follow suit in the effort to move the world into a more eco-friendly position.