Clean fuel trial could extend to all buses and taxis

More than 50 taxis in Minhang District are using a cleaner fuel that can be expanded to all the city's buses and taxis to help control PM2.5 pollution, legislators said yesterday.

Exhaust emissions from motor vehicles are the biggest single source of PM2.5, accounting for 25 percent of fine particles in the city's air, according to the Shanghai Environmental Protection Bureau.

The Minhang taxis are burning dimethyl ether - a non-toxic, cleaner-burning hydrocarbon gas that generates neither sulfur nor nitrogen particles, said Ding Kuiling, director of the Shanghai Institute of Organic Chemistry and a lawmaker.

"It is time for the city to expand new energy among buses and cabs, which would help better control PM2.5 pollution," Ding said.

Engines only need slight modifications for the fuel, while it will power vehicles for long distances without a refill, so few refuelling stations are needed, Ding said.

Dimethyl ether, somewhat similar to LPG gas, costs just 3,000 yuan (US$482.10) a ton, cheaper than gasoline, he said.

A dozen of the city's No. 147 buses launched a test operation using dimethyl ether in 2007 that showed it to be cleaner than conventional fossil fuel and safe.

The city has more than 300 buses using cleaner power sources, mainly electricity, hybrid technologies or dimethyl ether. Many were used during the 2010 Shanghai World Expo.

"There is no technical barrier to the expansion of new energy to the city's buses," said Yin Bangqi, an official with the city's Science and Technology Commission and also a legislator.

There are many companies in Shanghai that have been developing new energy for buses, Yin said. Refuelling and recharging stations are needed only at the terminus for buses, and they can be charged or refilled at night, he added.

Some simple refuelling locations should be built across the city for new-energy taxis, said Zhang Hailiang, managing director of Shanghai Volkswagen and another legislator.

Zhang said "fast charge" stations should be installed at public parking lots and commercial areas for urgent use and "slow charge" centers at residential areas and office buildings.