Latin America’s first water-powered bus on the streets of São Paulo

06 Jul 2009

Latin America's first hydrogen-powered bus in São Paulo, Brazil, is fueled by water and exudes clean vapor instead of fumes.
(Photos: UNDP)
New York - Imagine quiet, water-fueled buses and cars that exude clean vapor instead of fumes. In Latin America, this dream may be closer to reality, with the recent introduction of the region's first hydrogen-powered bus, in São Paulo, one of the world’s largest cities, with 18 million inhabitants – almost half of them riding buses every day.

The eco-bus does not emit a single gram of pollution, and is the first such initiative in Latin America, thanks to a Global Environment Facility  partnership among the United Nations Development Programme, the Brazilian Mines and Energy Ministry and the city of Sao Paulo’s Urban Transportation Company.

“Even though the technology to produce the hydrogen-fueled bus is already available in four other countries – China, the United States, Japan and Holland – the Brazilian project has been able to gather technology from national and international partner companies to produce hydrogen more cheaply," said Carlos Castro, UNDP Brazil’s environment expert.

The hydrogen used by the bus is obtained by electrolyses, a process that separates hydrogen and oxygen. Reacting with oxygen in the atmosphere, an electric current is produced. It runs the engine while releasing water vapor, instead of releasing carbon dioxide, as vehicles powered by gas and other oil-related products do.

"The process is totally clean, in a closed loop: it begins with water plus energy and ends with the same elements," said Carlos Zündt, planning manager of the Sao Paulo Urban Transportation Company and coordinator of the hydro bus project. "But our main goal at this point is not to completely replace the fleet – because the technology is still too expensive – but to study how a clean public transportation initiative would work in a huge city like Sao Paulo."  

The bus is hybrid: using hydrogen, three high power batteries, or both simultaneously. When running with hydrogen alone, the bus can run up to 300 km and 40 km extra only on batteries. 

The hydrogen bus can carry 63 passengers and will be tested over the next two months. During this period, the partners will study the effects on greenhouse gas emissions, the hydrogen production infrastructure and the effectiveness of the buses as public transport. 

“This is the first prototype, and was a result of four years of research and knowledge sharing by a consortium of national and international partners," Castro said. The consortium involves Brazilian energy companies AES Eletropaulo and Petrobras, and bus manufacturers Marcopolo and Tuttotrasporti. The international partners are Ballard Power Systems and Hydrogenics (both from Canada); Epri International (USA) and Nucellsys (Germany). “This enabled us to get the high quality contribution from companies that are researching hydrogen fuelled-transportation all around the world. Lessons were learned from other countries’ experiences.”

An energy plant to produce hydrogen by electrolysis is also under construction, and will be ready in six months. Until then, the new bus will produce hydrogen by processing natural gas.

Hydrogen is considered a promising alternative to fossil fuels. Today, there are only 5,000 vehicles worldwide that produce energy from this gas. According to the International Partnership for the Hydrogen Economy, in 2015 the fuel should be widely distributed, though mainly in Europe and the United States.

Hydrogen is forecast to be widely available in Brazil only by 2020. “Researchers estimate that by 2080, 90 percent of the world’s vehicles will be run by hydrogen,” Zündt added.

Though abundant and clean, hydrogen is still very expensive to produce. That's why oil-related fuels are still being used today.

"Diesel is much cheaper [than hydrogen]," Zündt acknowledged. "But it is a highly pollutant fuel. So we must also consider the costs of public spending in respiratory diseases and other horrible effects of pollution and acid rain. If you take that into account, diesel has a cost 200 times higher than hydrogen."

The consortium involved in the project is also interested in exporting the hydrogen-fueled buses. Unlike many developing countries, Brazil has a large, modern and competitive bus industry, and builds up to 20,000 buses a year – one of the top bus producers in the world. Over time, the partners hope to make this lower-cost technology available to other developing countries – to offer a cleaner environment to all.