CHICAGO (WBBM/CBS) — Pace officials are looking at alternative fueling for its buses.

As WBBM Newsradio 780’s Bob Roberts reports, in the past month, officials took a look at a bus fueled by compressed natural gas and heard a sales pitch. But a top Regional Transportation Authority official says the agency should think twice.

LISTEN: Newsradio 780’s Bob Roberts reports

When RTA deputy executive director Grace Gallucci worked for the transit agency in Cleveland, she saw the price of natural gas for its buses triple.

Gallucci says diesel fuel became much cleaner, and was competitive in price.

“We really have to look at the benefits in the short-term and in the long-term, and really think oftentimes of almost like a stock portfolio,” Gallucci said. “You might need a balance of different forms of fuel in order to protect yourself from the market variances.”

Last month, Pace officials said the agency was paying $2.85 a gallon, 50 cents a gallon more than budgeted. Pace its diesel fuel in bulk, but on the spot market.

Representatives from North American Bus Industries (NABI) pitched an option last month to buy 45-foot buses powered by natural gas.

NABI has a spotty history in Chicago. The CTA purchased more than 200 articulated NABI buses in 2003-04, but removed them from service prematurely in February 2009, amid countersuits, because of cracks found in the buses’ frames, particularly around the articulation joints, axles and suspensions.

CTA alleged that the overall workmanship and design was deficient, charges that NABI denied.

The bus NABI showed Pace board members this week is not articulated. Executive Director T.J. Ross said more than 500 identical buses are running well in Los Angeles, and nearly 100 have had few problems in Phoenix.

NABI compressed natural gas buses are also in use in smaller fleets in two Illinois cities — Springfield and Rock Island.

Although impressed by the presentation, Pace officials have not committed to purchasing a bus powered by natural gas.

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