This week the city of Buenos Aires gets its first “eco-bus,” which has a hybrid engine that runs on electricity and diesel, emitting 40 percent less greenhouse-effect gas, but costing four times more than a conventional bus. The goal is to add five more of these buses in 2011, after this pilot effort. The manufacturing is entrusted to the city government, the National University of La Plata, and the private sector.

According to the Buenos Aires Environment Ministry, 37 percent of the city's greenhouse gases come from public passenger transportation, which has a fleet of 9,500 vehicles.

Minister Diego Santali told Tierramérica that the eco-buses “will reduce respiratory illness, consume less fossil fuel, and will also reduce noise pollution.”