Metro hybrid bus program

Large containers of water are "sitting in" for passengers during the first phase of road testing.

Updates

• Coach 2599 keeps going and going and going...�Feb. 27, 2003
• Early indications�Jan. 10, 2003

Coach 2599 keeps going and going and going...

By Todd Gibbs, Hybrid Bus Project Manager

February 27, 2003�Coach 2599, Metro Transit's experimental hybrid bus, is earning the nickname "The Energizer Bunny" as it continues making its rounds over and over again along King County bus routes.

Since early October, Metro has been testing, poking, prodding, using and abusing Coach 2599. Currently, the odometer shows more than 42,000 miles. We have just finished a 90-day stress test, during which we accumulated over a year's worth of mileage (37,600) with a ballast load equal to a full standing load of passengers (11,000 lbs.). To conduct the test, Transit Operations supplied more than a dozen operators to drive the hybrid 20 hours per day, seven days per week in simulated service, including trips through the downtown bus tunnel. The remaining four hours each day were used by the maintenance staff at Central Base for fueling, repairs and scheduled maintenance.

During the mileage accumulation we saw no "yard delays" and only three problems that kept the bus from maintaining its 400+ miles-per-day average. Two of the three problems-a plugged fuel filter, a broken exterior mirror and a malfunctioning pressure solenoid inside the drive unit-were unrelated to Coach 2599's hybrid technology. The third-a malfunctioning pressure solenoid-while hybrid-related, was easily repaired with a replacement part from Pacific Diesel. (Allison, maker of the hybrid transmission, uses the same solenoid in its drive units as those used in their World transmissions.)

Just prior to the start of the stress test, and every 30 days afterward, Central Base staff performed exhaustive maintenance inspections to monitor the bus's performance. Included in these inspections were measurements of the brake lining and drums on all three axles, and oil analyses on the engine, drive unit and drive axle. Based on the data we have collected, we can predict brake life roughly equivalent to that on our existing contemporary fleets, and we may be able to extend engine oil change intervals by as much as 200 percent. Allison maintains that its drive-unit oil will have at least a 100,000-mile change interval.

During the Phase I stress test, fuel economy, battery usage and condition, and propulsion component operating temperature data was collected daily. I am encouraged to see that our hybrid bus, running in a worst-case scenario, has been achieving better fuel economy than any of our conventionally powered fleets running in normal service. We are seeing a nearly 30 percent increase over the New Flyer high floor buses and 40 percent over the Breda fleet. I am anxious to see the fuel economy of the hybrid during Phase II testing (actual revenue service) in March. We expect the numbers to go even higher.

This bus has performed remarkably well. The operators have expressed their pleasure in its performance and the staff at Central Base is amazed at how little maintenance the bus has required. From my perspective, I have nothing but praise for Allison, its field support, and its Parallel Hybrid System. This truly is "an electromechanical thing Of beauty," as Allison's promotional video on the hybrid proclaims.

The success of this project is due in large part to the dedicated people at Central Base, both in maintenance and operations. Without them, our break-neck test schedule could not have been maintained. Thank you!

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Bird's-eye view of coach 2599.

Early indications

Our first look at Coach 2599's performance and potential

By Jim Boon, Vehicle Maintenance Manager

January 10, 2003�Coach 2599, Metro's New Flyer Hybrid Electric bus, continued operating 20 hours per day without incident throughout the 2002 holiday season. Its performance remains excellent and we remain encouraged about this vehicle's potential.

Going into early January, we have accumulated approximately 26,000 miles life-to-date on the bus and 22,000 miles in our structured Phase One test. During Phase One, Coach 2599 travels 20 hours per day, seven days per week, over Metro bus routes, averaging 14 trips through the downtown bus tunnel each day. Considering that the bus is loaded with 11,000 pounds of water ballast, we are receiving some excellent fuel economy numbers. Preliminary data (subject to some interpretation because we are carrying an excessive gross vehicle load) show a consistent 20 percent improvement over a conventional artic bus. Fuel economy is expected to further improve once we start Phase Two testing, carrying real passengers-which will reduce our average gross load.

Our technical staff has been performing vehicle inspections on regular 6,000-mile intervals, as we do with all buses in our fleet. Brake and tire wear appear consistent with our other buses. We normally change engine oil at 6,000 miles, but have not changed the oil in the hybrid bus at all. We are analyzing the oil at each 6,000-mile interval and will change it when the wear indicators tell us that a change is needed.

The hybrid mechanical/electrical drive system continues to operate without issue. Coach 2599 has had two incidents that might have produced a trouble call had it been in service, but in both cases the shop repairs were minor enough to have allowed the bus to remain in uninterrupted service. For all practical purposes, Coach 2599 has given us 100 percent availability over the last 22,000 miles.

Due to the excellent performance of the hybrid bus, we are ahead of our mileage-accumulation schedule. At the present rate, we will have 36,000-40,000 miles in Phase One by late February, and will begin Phase Two in early March.

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Last update: January 23, 2003, at 11:55