City reaches 'critical mass' of green vehicles

The City of Chicago has made progress in greening its vehicle fleet, and is beginning to use hybrid trucks to repair streetlamps and change light bulbs.

“We’ve reached a critical mass of green light duty vehicles,” said Matt Stewart, Senior Automotive Equipment Analyst with the Department of Fleet Management. He spoke at the Green Truck Summit, a national conference held this week at McCormick Place.

“The majority of the city’s fleets are medium to heavy duty, and that’s a big chunk of what we’re trying to get into hybrids,” he said.

At the summit, the city unveiled its first medium-duty hybrid vehicle. The truck is fitted with an aerial bucket that can operate even with the engine turned off, eliminating an estimated 90 to 95 percent of idle fuel consumption, according to Navistar, the vehicle’s manufacturer.

The vehicle cost the city of Chicago $195,000. Stewart said medium- to heavy-duty hybrid trucks are much more expensive than light-duty hybrids, though often the vehicles do pay for themselves in fuel and emissions savings.

“The upcharge on a light duty vehicle is $4,000 to $8,000. The upcharge on a medium or heavy duty vehicle is upwards of $80,000,” he said. “We’re anticipating that financial savings are going to grow as more hybrid utility vehicles are produced. Until that happens, we’re not going to buy every truck a hybrid.”

About 7 percent of the city’s 9000 on-road vehicles either are hybrid or run on alternative fuels like natural gas and ethanol. Most of those are light-duty vehicles. Of the medium to heavy duty vehicles—only one of which is hybrid—32 percent have either an exhaust retrofit, an idle shut-down function that turns the engine off after five minutes of idling or both.

Marian Wang is a Chicago-based reporter. She covers environmental issues for the Daily News.