Group says pilot program helped clean emissions from Mexico City buses

By: ANTHONY HARRUP - Associated Press | Wednesday, May 25, 2005 11:10 PM PDT ∞

MEXICO CITY -- A pilot project aimed at cleaning up diesel buses reduced emissions in Mexico City test vehicles by as much as 90 percent, officials said Wednesday.

The project, sponsored by environmental and government groups, retrofitted 20 public buses to burn ultra-low-sulfur diesel.

Environmentalists called on Mexico City to adopt the technology for all of its buses, saying the sprawling, mountain capital could drastically reduce smog and pollution levels.

However, promoters of the project say they're far from securing a supply of the fuel from state oil monopoly Petroleos Mexicanos.

Under the pilot project, a dozen 2001 model buses were fitted with particle traps and fueled with ultra-low sulfur diesel, or ULSD, which was imported for the test.

Particle and carbon monoxide emissions were lowered by 90 percent, and emissions of nitrogen oxides fell by 10 percent, said Luz Elena Gonzalez, director of the city's 1,300-strong fleet of passenger buses, said at a press conference Wednesday.

Older buses that were fitted with oxidation catalysts saw lower reductions in carbon monoxide emissions, but greater reductions in nitrogen oxides.

The project is being sponsored by the U.S. Environmental Protection Agency, the Washington-based World Resources Institute and the U.S. Agency for International Development, with the participation of numerous other local government and private groups.

Mexico's 1995 Nobel chemistry prize winner Mario Molina, who is coordinating a 10-year project to improve air quality in the country's capital, said the purpose of the tests was to determine how well the new technology would work in Mexico City's thin air at 7,200 feet (2,160 meters) above sea level.

The test proved successful, but Pemex is still far from turning out ULSD, which should contain a maximum 15 parts per million of sulfur.

The company's chief executive, Luis Ramirez Corzo, said at a press conference Tuesday that Pemex is producing fuel with sulfur content of 250 parts per million (ppm) -- down from 500 ppm -- and is aiming for 50 ppm million by 2008, which will require investment of US$2 billion.

"We haven't got the funds secured, and it's part of discussions with the Finance Ministry to achieve an adequate budget," he said.

Molina suggested that the cost of upgrading Pemex's refineries to produce the cleaner diesel could be recovered gradually with a surcharge on the fuel.

"The economic aspect of it can be resolved," he said.

Lee Schipper, director of research at the World Resources Institute's transport and environment center EMBARQ, said there are 10 large cities in Mexico that need the cleaner diesel, which should guarantee a market large enough for Pemex to bring forward its plans.

According to studies by Molina, every year 2.5 million working days are lost in Mexico City to health problems caused by particulate matter such as soot, and ozone pollution, with diesel-fueled freight and passenger vehicles the main cause of those contaminants.