IC Bus LLC (Lisle, Ill.) in November was showcasing its new CE Series school bus at the National Association for Pupil Transportation’s 40th annual Summit in Kansas City, Mo. IC Bus will manufacture the propane-fueled CE Series at its assembly plant in Tulsa. Deliveries will begin this summer, and buses will go into service at the start of the 2015-2016 school year.

The company has teamed with Power Solutions International (PSI; Wood Dale, Ill.) for the power plant, an 8.8-liter LP engine with a rating of 565 lb ft. at 1500 rpm. The CE Series also integrates the Allison 2500 transmission with FuelSense to maximize fuel economy. Collaboration between the two companies began when Troy Clarke, CEO of IC Bus’ parent company, Navistar, drove a medium-duty test truck featuring the liquid-injected 8.8-liter. “He was amazed that we were able to create an alternative-fuel engine that drives quietly, but with the power of a diesel engine,” says Eric Cohen, PSI’s COO.

According to Don Wilkins, vice president of advanced product development for PSI and the main architect of the engine, one of the 8.8-liter’s major advantages for school bus fleets is its ability to handle a wide range of transmission options—an important consideration for districts with rugged and challenging terrain. The engine is said to work seamlessly alongside transmissions from heavy-duty suppliers such as Allison. “The acceleration is smooth, quiet, and delivers diesel-like performance,” adds Wilkins. “There’s no need to rev the engine out. It will simply climb the hill and be happy about it.”

IC Bus notes that, when factored with propane’s inherent benefits, such as ease of storage compared to other fuels, the new 8.8-liter-powered CE Series bus products have the potential to be game-changers. “Propane is a great fuel because you can get a provider to drop a tank anywhere in America,” Cohen points out. “That means you can run longer routes without having to worry about finding a fuel station. Plus, we’ve seen municipalities cut their fuel costs in half, and at the same time there are less pollutants in the air.”