NYCT OPERATING EXPERIENCE WITH HYBRID TRANSIT BUSES Gary LaBouff Director, Research & Development May, 2006
Mar 29, 2015
NYCT OPERATINGEXPERIENCE
WITH HYBRID TRANSIT BUSES
Gary LaBouff
Director, Research & Development
May, 2006
Overview of NYCT Bus Operations
NYCT Bus Operations (2005)
Annual Bus Customers 740,586,160 Average Weekday Ridership 2,361,299 Total Buses in Fleet 4,512 # of Bus Routes 243 # of Bus Stops 12,693 # Of Total Employees 14,061 Annual Mileage 119,495,228 Gallons of Fuel Consumed
Diesel
41,116,861 CNG
7,156,336
NYCT Bus Fleet
End of Year
Type 2003 2004 2005 2006
Transit Buses40' Two Stroke Diesel 580 167 0 040' Four Stroke Diesel 2,655 2,531 2,504 2,36560' Four Stroke Diesel 420 630 630 63040' Four Stroke CNG 221 481 481 48140' Diesel Hybrid 10 141 335 474
Coaches45' Four Stroke Diesel 570 572 572 572
Totals 4,456 4,522 4,522 4,522
1. Reduce Bus Fleet Emissions- Achieve levels below current U.S. mandates
2. Improve Service- Improve equipment reliability
- Achieve quieter operation
3. Reduce the Cost of Operations
- Improve fuel economy
- Reduce maintenance costs
- Avoid infrastructure costs
NYCT Goals
The Clean Fuel Solution - Hybrid Electric
Hybrid Electric buses combine a diesel engine 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
BAE/Orion VII Hybrid System
Lead Acid Battery Packs
DieselEngine
Generator
ElectricTraction Motor
PowerElectronics
Lead-Acid Batteries
Diesel Engine
Generator
Power Electronics (PCS)
Traction Motor
NYCT Hybrid Bus Programs
NYCT Hybrid Bus Programs - Overview
Successful prototype in 1996 (Orion/GE)
Pilot fleet of 10 Orion VI/BAE hybrid buses began revenue service in 1998
125 Production Orion VII/BAE Gen. I hybrid buses ordered - pilot bus in 2003, production deliveries in 2004
200 Production Orion VII/BAE Gen. II hybrid buses ordered - pilot bus in 2004, production deliveries in 2005
500 Additional Orion VII/BAE Gen. II+ ordered, (216 NYCT,284 MTA BUS) - Delivery by 6/07.
Revenue Service Experience - Orion VI
Hybrid buses in service since Sept. 1998
Met standard performance specs
Approx. 700,000 revenue miles
Drivers and customers like the buses
Brake life approximately doubled
Very positive - for a brand new technology, have exceeded expectations
Orion VII/BAE Hybrid Buses - Gen. I First of 125 into service in February, 2004
As of 1 April 2006:
125 Buses in service
Approx. 5.5 million revenue service miles to date
Two depots; Bronx & Queens
Used interchangeably with standard buses
Fuel economy and emissions better than Orion VI hybrid buses
Orion VII/BAE Hybrid Buses - Gen. I Design Improvements over Orion VI
Active Control of Generator
Variable engine speed
Improved Traction Motor
Planetary gear reduction
Redesigned bearing system
Redesigned Packaging
Particulate Filter with Active Control
Improved Diagnostic System
Improved Re-gen Control for Smoother Braking
Orion VII/BAE Hybrid Buses - Gen. II
First of 200 into service in December, 2004
As of 1 April 2006:
200 Buses in service
Over 3.5 million revenue service miles
Two depots, Brooklyn and Manhattan
Smoother and quieter than Generation I
Orion VII/BAE Hybrid Buses - Gen. II Design Improvements over Orion VII Gen. I
New Generator - Flywheel Mounted - (currently being redesigned)
New Design Coolant/Lube Pumps
Oil Cooled Propulsion Control System
Improved Accessibility
Software Upgrade
Updated engine - EGR with common rail fuel system
Orion VII Hybrid Bus Revenue Miles
0
2,000,000
4,000,000
6,000,000
8,000,000
10,000,000
Cum
ulat
ive
Mile
s
NYCT Fleets Composite Fuel Economy
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0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
Standard Diesel (No EGR)
Standard Diesel(EGR)
CNG NYCT Orion VIHybrid
NYCT Orion VIIHybrid
MPG
Emissions Comparison
Dynamometer Results - CBD Cycle
Reference:
Orion VII Transit Bus Equipped with BAE Systems HybriDrive TM Propulsion System (MY2004): Emissions and Fuel
Economy Test Report' Environment Canata Technology Centre, ERMD Final Report #04-18, September 2004.
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
Conventional Diesel (no EGR, DPF)
Conventional Diesel(EGR, DPF)
Compressed Natural Gas Diesel/Electric Hybrid (EGR, DPF)
g/m
ile
NOx Particulates x 100 CO CO2/1000
EPA Regulated Emission Levels for Heavy Duty On-Highway Engines - PM & NOx
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0.1
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0 1 2 3 4 5 6 7 8 9 10NOx (g/hp-hr)
PM
(g/h
p-hr
)
1988
1990
1991
199419982004
2007-2010
Hybrid Bus Reliability (MDBF)
01
6 Month
Rolling Average
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
Jan-
04
Mar
-04
May
-04
Jul-0
4
Sep
-04
Nov
-04
Jan-
05
Mar
-05
May
-05
Jul-0
5
Sep
-05
Nov
-05
Jan-
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-06
MD
BF
(m
iles) 6 Month
Rolling Average
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 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
Hybrid Electric Costs
Life Cycle Costs - HEV vs Standard Current differential in acquisition costs make
justification of HEV’s, based on costs alone, difficult at today’s fuel prices
Current hybrid differential is $125-200K per bus
Series HEV’s in NYCT high density duty cycle can achieve over 30% improvement in fuel economy over standard diesel/transmission systems
This can result in a savings of approx. 50,000 gallons of fuel over a 12 year life of the bus.
If today’s fuel prices double, the savings can negate the initial cost differential.
Fuel Costs - Series HEV vs Std. Propulsion
$0
$50,000
$100,000
$150,000
$200,000
$250,000
$300,000
$350,000
$0 $1 $2 $3 $4 $5
Fuel Cost ($/gal)
Hy
bri
d F
ue
l S
av
ing
s -
12 Y
ea
r L
ife
Baseline: > Standard Diesel 40' Bus > Transit Duty Cycle
2002
2003
2004
2005 Average Fuel Prices
Heavy Urban
Suburban
2006
Life Cycle Costs - HEV vs Standard
Other factors contribute to HEV cost savings
Brake life
Diesel Particulate Filter maintenance HEV system can control regeneration process and
reduce filter problems
Transmission overhaul
Other non-cost factors favor hybrids
Lower noise signature
More flexibility in vehicle energy management Emissions
Lessons Learned from Hybrid Buses
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
Lessons Learned - Maintenance More advanced troubleshooting procedures and
tools required
More components and subsystems/interfaces
More wiring and connectors
Long term, reliable, and cost effective energy storage solution still not clear
Lead acid batteries have limited life and can be reliability drivers due to the number required
NiMH still expensive and life unproven
Ultra capacitors, Lithium Ion batteries still in development.
NYCT Hybrid Bus - Future Plans
Evaluate alternative energy storage technologies
Evaluate alternative hybrid system technologies
Continue to develop integrated diagnostic/prognostic systems
Pursue goal of 10,000 hour MDBF for hybrid buses
Move toward all electric accessories
Hybrid Buses - Future Challenges
Component Optimization - HEV allows for the use of other electrically driven system components.
Electric components have inherent advantages:
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:
Gary LaBouff, Director - Research & Development
MTA New York City Transit
(718) 566-3535; [email protected]
Hybrid/CNG/Diesel Emissions Report
www.navc.org/emissionsreport.html
NREL Reports:
www.afdc.doe.gov/resources.html
reports 6369 and 6383