Benefits of Fuel Cell Range Extender for Medium Duty Application Aymeric Rousseau, Phil Sharer Presented by: R. Vijayagopal Argonne National Laboratory, USA
Objectives What is the impact of doubling the BEV range using a fuel cell range extender on the vehicle LevelizedCost of Driving (LCOD) What size should the fuel cell system be? What is the manufacturing cost benefit? What is the operating cost benefit? What effect does the addition of the fuel cell system have on vehicle mass, battery power, battery capacity and motor power?
Methodology: Parametric Sweep of Fuel Cell Power and On-Board Hydrogen 1. Define Class 4 reference BEV 2. Resize the BEV to double the AER 3. Different fuel cell stack powers were chosen (10 to 20kW every 2.5 kw) 4. For each fuel cell stack power, different amounts of on board H2 were chosen (2 to 8kg every 2kg) 5. The battery was resized (both power and energy) to account for the additional energy from the fuel cell 6. The control was tuned so that the AER range was completed with an empty tank. Fuel cell system used at its peak power. 1. 2. 3. 4. 5. 6.
Sizing Algorithms Were then Used to Define the Vehicles and Run the Drive Cycles Using Distributed Computing Vehicles Automatically Sized Distributed Computing Autonomie Postprocessing API 4500.a_process Fuel Cell Elec + Storage Consumption ($) Elec Consumption Fuel (W.h/mile) Cell + Storage ($) Manufacturing Cost ($) (W.h/mile) Fuel Cell Power Fuel On Cell Threshold Power On (kw) Threshold (kw) Power-2(kW) 4000 250 Power-3(kW) Power-2(kW) Power-3(kW) Power-4(kW) Power-5(kW) Power-4(kW) Power-3(kW) Power-6(kW) Power-5(kW) Power-4(kW) Power-7(kW) Power-6(kW) 3500 200 25 Power-5(kW) Power-8(kW) Power-7(kW) Power-6(kW) Power-9(kW) Power-8(kW) Power-7(kW) Power-9(kW) Power-3(kW) Power-8(kW) Power-11(kW) Power-4(kW) Power-9(kW) Power-12(kW) Power-11(kW) 3000 150 25 Power-5(kW) 20 Power-13(kW) Power-12(kW) Power-6(kW) Power-11(kW) Power-14(kW) Power-13(kW) Power-7(kW) Power-12(kW) Power-14(kW) Power-8(kW) Power-13(kW) Power-2(kW) Power-9(kW) Power-14(kW) Power-25(kW) 100 250 20 15 Power-3(kW) 2500 Power-30(kW) Power-25(kW) Power-35(kW) Power-4(kW) Power-11(kW) Power-30(kW) Power-5(kW) Power-12(kW) Power-25(kW) Power-40(kW) Power-35(kW) Power-6(kW) Power-13(kW) Power-30(kW) Power-45(kW) Power-40(kW) Power-7(kW) Power-14(kW) Power-35(kW) 4500 Power-50(kW) 200 50 15 10 Power-45(kW) Power-8(kW) Power-40(kW) 2000 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-50(kW) Power-9(kW) Power-45(kW) 1.8 2 Power-25(kW) Power-50(kW) 3 x 104 Power-11(kW) Power-30(kW) Power-12(kW) Power-35(kW) 4000 Power-2(kW) 150 10 05 Power-13(kW) Power-2(kW) Power-40(kW) 2.9 Power-3(kW) 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-14(kW) Power-45(kW) 1.8 2 Power-4(kW) Power-3(kW) Power-50(kW) Power-5(kW) Power-4(kW) 2.8 Power-6(kW) Power-5(kW) Power-25(kW) 100 Power-7(kW) Power-6(kW) 3500 50 Power-30(kW) Power-7(kW) 2.7 Power-8(kW) 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-35(kW) 1.8 2 Power-9(kW) Power-8(kW) Power-40(kW) Power-9(kW) 2.6 Power-45(kW) Power-11(kW) Power-50(kW) 50 Power-12(kW) Power-11(kW) 3000 0 Power-12(kW) 2.50 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-13(kW) 1.8 2 Power-14(kW) Power-13(kW) Power-14(kW) 2.4 2500 0 Power-25(kW) 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-25(kW) 2.3 Power-30(kW) 1.8 2 Power-35(kW) Power-30(kW) Power-40(kW) Power-35(kW) 2.2 Power-45(kW) Power-40(kW) Power-50(kW) Power-45(kW) 2000 2.10 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Power-50(kW) 1.8 2 2 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 >300 individual vehicles simulated
Reference BEV Class 4 (Similar to Navistar Estar) Assumption Value Vehicle test weight 3900 kg (baseline) Transmission type Automatic Transmission 3.1, 1.81, 1.41, 1, 0.71 Motor type Permanent magnet Motor power 70 kw Battery type Li-ion Battery power 345 W/cell, 83 kw/pack Battery energy 327 Wh/cell, 80 kwh/pack Battery capacity 84 Ah/cell Nominal voltage 317 V Number of cells 80series x 3 parallel strings (240 cells/pack) Rolling resistance 0.0075 Coefficient of drag 0.56 Frontal area 4.7500 m 2 Fuel cell APU peak eff. 60% (50% at rated power) Fuel cell idles all the time True Payload 1,159 kg
Fuel Cell System and Hydrogen Storage Cost Assumptions Fuel Cell Stack Cost Fuel Cell Rated Power (kw) 2010 $/kw at 10,000 Units/yr Total Cost (2010 $) 15 298.33 4,475 14 333.5 4,670 12 404.0 4,848 10 474.4 4,744 8 544.6 4,359 6 615.3 3,692 5 650.51 3,253 Hydrogen Storage Assumptions 700 bar Fuel Cell Rated Energy (kg) 2010 $/kwh at 10,000 Units/yr Total Cost (2010 $) 4.0 12.29 1,639 3.0 13.13 1,313 2.0 14.52 968 1.0 19.08 636 0.5 28.05 468 Source Strategic Analysis Current cost at 10,000 units/year
LevelizedCost of Driving Assumptions Assumption Time frame 2015 Vehicle lifetime Carbon cost per mile 0 Noncapital cost per mile 0 5 years Charger efficiency 88% Discount rate 0 Retail price equivalent 1.5 Annual miles traveled Fuel hydrogen Electricity cost NPV fuel and electricity combined discount factor 14,529 mi $3.50/gge $0.11/kWh 1 Value
The Electrical Consumption Decreased Proportionally as Fuel Consumption Increased Until 6 kg of H2 The electrical energy consumption was close to zero with 6kg of H2. The addition of more energy forced the range out of bounds. Battery Elec Electrical Consumption Consumption (W.h/mile) (Wh/mile) 400 350 300 250 200 150 100 50 Fuel Consumption (l/100km) 9 8 7 6 5 4 3 0 Onboard H2 Weight (kg) 2 Onboard H2 Weight (kg)
Battery Cost Decreased by 80% While Energy Decreased to Less than 10kWh The battery transitions from a high energy to a high power battery. Basically, the fuel cell at this value is supplying the average load on the vehicle while the battery is handling transients. $37500 for BEV Battery Cost ($) 3 x 104 2.5 2 1.5 1 Battery Energy (kw.h) 80 70 60 50 40 30 20 0.5 10 0 Onboard H2 Weight (kg) Cost of 2X ranged BEV Vehicle based on 250 $/kwh for battery Cost of 2X ranged BEV Vehicle based on 500 $/kwh for battery 0 Onboard H2 Weight (kg)
The Cost of Fuel Cell System and its Storage Increases by $2500 when Increasing the H2 Weight from 2 to 8kg Fuel Cell + Storage ($) 9500 9000 8500 8000 7500 7000 6500 6000 5500 Mass of Fuel Consumed (kg) 9 8 7 6 5 4 3 5000 Onboard H2 Weight (kg) 2 Onboard H2 Weight (kg)
The Total Manufacturing Cost Saving is Close to $11500 Manufacturing Cost ($) 6 x 104 5.5 5 4.5 4 $59600 for BEV $46000 for FC HEV 70kW Fuel Cell 4.64 kg of H2 160 mile HTUF range 3.5 3 Onboard Mass H2 Weight (kg) (kg) Cost of 2X ranged BEV Vehicle based on 250 $/kwh for battery Cost of 2X ranged BEV Vehicle based on 500 $/kwh for battery FC 30$/kW, ESS 250 $/kwh
1.29 $/mile for BEV LevelizedCost of Driving Decreased by 40% with 6 kg of H2 1.25 1.2 1.15 1.1 LCOD ($/mile) 1.05 1 0.95 0.9 0.85 0.8 0.75 Onboard H2 Mass Weight (kg) (kg) Cost of 2X ranged BEV Vehicle based on 500 $/kwh for battery
Impact of Cost Assumptions on Fuel Cell Range Extender Benefits 500 $/kwhr, 8 $/gge, 5 year/lifetime, 15Kmile/year 500 $/kwhr, 3.5 $/gge, 10 year/lifetime, 15Kmile/year 250 $/kwhr, 8 $/gge, 5 year/lifetime, 15Kmile/year 500 $/kwhr, 3.5 $/gge, 10 year/lifetime, 30Kmile/year
Fuel Cell Range-Extender Shows Great Cost Reductions Promises to Double the Range of Current BEVs Based on the cost assumptions and drive cycle considered: Fuel Cell is cheaper than a battery to storage energy Battery is cheaper than a fuel cell to deliver power Using the fuel cell close to its rated power (i.e., maximum power control) would provide the lowest LCD For the drive cycle considered, a 10-20 kw fuel cell system with 6 kg of H2 would provide a good solution The fuel cell range extender option consistently reached a lower LCOD when compared with a BEV with twice the original electric range when the cost of the fuel cell was considered at a production level of 10,000 units. The results are impacted by H2 cost, vehicle life, driving distance, battery cost However, the fuel cell range extender option consistently reaches a lower LCD compared to a BEV with twice the original electric range
Acknowledgments We would like to thank Pete Devlin from the U.S. Department of Energy (DOE) for supporting the study as well as Strategic Analysis for providing fuel cell system and hydrogen storage cost assumptions.