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NYCT Operating Experience with Hybrid Buses. John P. Walsh Chief Maintenance Officer MTA New York City Transit Department of Buses November 30, 2004. Outline. Overview of NYCT Bus Operations Hybrid Electric Bus Technology NYCT Hybrid Bus Projects Lessons Learned with Hybrids
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NYCT Operating Experience with Hybrid Buses John P. Walsh Chief Maintenance Officer MTA New York City Transit Department of Buses November 30, 2004
Outline • Overview of NYCT Bus Operations • Hybrid Electric Bus Technology • NYCT Hybrid Bus Projects • Lessons Learned with Hybrids • Future Plans
NYCT Bus Operations • Annual Bus Customers 762,190,226 • Average Weekday Ridership 2,452,554 • Total Buses in Fleet 4,500 • # of Bus Routes 218 • # of Bus Stops 12,355 • # Of Total Employees 14,388 • Annual Mileage (2003) 121,255,903 • Gallons of Fuel Consumed (2003) • Diesel 44,129,685 • CNG 3,695,157
NYCT Bus Fleet *Two-stroke engines to be retired from DOB fleet by end of 2004.
The Clean Fuel Solution - Hybrid Electric • Hybrid Electric buses combine a dieselengine and electric drive components • Improved performance • Significant emissions reduction • Increased fuel economy • Smooth and quiet operation • Avoids the infrastructure costs of CNG - no special fuel handling is required
NYCT Hybrid Bus Programs • Successful prototype in 1996 (Orion/GE) • Pilot fleet of 10 hybrid buses began operating in revenue service in 1998. • First production order of 125 delivered in 2004. • Second production order of 200 to be delivered in 2005.
Hybrid Revenue Service Experience • Hybrid buses in service since Sept. 1998 • Approx. 700,000 revenue miles on pilot fleet to date • Approx. 800,000 revenue miles on new production fleet to date. • Drivers and customers like the buses • Brake life approximately doubled • Very positive - for a brand new technology, have exceeded expectations
Orion VII/BAE New Production Hybrid Buses - In Service Performance • First of 125 into service in February, 2004 • 100 buses in service as of November at two depot locations with different duty cycles. • Used interchangeably with standard buses • No major propulsion system problems to date • Emissions significantly better than other buses: • NOx less than half that for a ‘clean diesel’ or CNG bus • CO less than one fourth that for a ‘clean dlesel’ and roughly one tenth that for a CNG bus.
Orion VII/BAE New Production Hybrid Buses - In Service Performance • The baseline fuel consumption is 2.3 MPG for 40-foot standard diesel buses • The hybrid buses have demonstrated the following fuel consumption to date: • Clara Hale Depot – 3.7 MPG • Queens Village Depot – 3.4 MPG • The hybrid bus fuel consumption is reduced approx. 40% compared to the standard diesel buses they replace. This equates to nearly 5000 gallons of diesel fuel saved per year for each bus.
Hybrid Bus Reliability (MDBF) 2500 2000 1750 1500 1250 1000 750 500 250 00 00 00 00 00 00 01 01 01 01 01 01 02 02 02 02
Hybrid Bus Availability % of Hybrid Fleet Availability 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Jun-99 Sep-99 Dec-99 Mar-00 Jun-00 Sep-00 Dec-00 Mar-01 Jun-01 Sep-01 Dec-01 Mar-02 Jun-02
Orion VI Lead Acid Battery Life • For the 36 months of testing ending in February of 2004: • 17,000,000 Battery-miles, 5% replaced • Replaced batteries did not appear to be ‘end-of- life’ failures • Two buses with Optima batteries in service for 40+months with no failures • Life goal of 3 years appears to be potentially achievable but not realized yet • Changes to software in Orion VII should reduce battery replacements
Battery Type Life/Cost Comparison Lead-Acid Technology is still the cost winner … for now
Life Cycle Costs - Hybrid vs. Standard Propulsion in Transit Duty Cycle • Current differential in acquisition costs make justification of HEV’s difficult • Current range differential is $125- 200 K per bus • Series HEV in NYCT high density duty cycle achieves > 35% better fuel economy than standard propulsion system • Average bus 32k/m/yr uses 13,000/gal/yr diesel fuel @$2.00/gal annual fuel cost $26K • HEV will use 8,800 gal/yr @ $2.00/gal annual fuel cost $17,600 - differential of $8,400/ yr • Over 12-year life minimum differential $100K • Delta will increase as cost of fuel increases @ a half life assumption of $3.00/gal the differential exceeds $125K
Life Cycle Costs - Hybrid vs. Standard Propulsion in Transit Duty Cycle
Lessons Learned - Operational • Bus operators and passengers like hybrids • Quiet, smooth operation • excellent acceleration/smooth braking • “feels” like a standard bus • little or no operator training required • Able to be used on all NYCT routes • Bus does not roll back on hills • More advanced troubleshooting procedures and tools required
Hybrid Bus - Future Challenges • Revise current EPA heavy duty certification protocol to allow for system evaluation. Tailpipe emissions vs. engine dyno results. • Chassis dyno testing is what is used for cars and light duty trucks. • Allows for evaluation of total system performance. • Much better representation of actual in-service performance of vehicle. • Measures the overall effects of other propulsion system components.
Hybrid Buses - Future Challenges • Energy Storage - encourage additional development, testing, and deployment of other energy storage systems: • Advanced batteries • Lead Acid • NiMH • Sodium • Other • Ultra Capacitors • Power from grid • Solid fuels for fuel cells
Hybrid Buses - Future Challenges • Component Optimization - HEV allows for the use of other electrically driven system components. • Electric components have inherent advantges: • Remote mounting - better packaging • More efficient • High reliability index • Reduced noise signature
Hybrid Buses - Future Challenges • Opportunities for Electrically Driven Accessories: • Short term • Compressors, air and HVAC • Steering • Cooling system • Long Term • Wheel motors • ZPE operation • Fuel cell integration
Additional Information • Speaker Contact: John P. Walsh, Chief Maintenance Officer MTA New York City Transit (347) 643-5100; jowalsh@nyct.com • Hybrid/CNG/Diesel Emissions Report www.navc.org/emissionsreport.html • NREL Reports: www.afdc.doe.gov/resources.html reports 6369 and 6383