ATT Conference Barcelona, October 1-3, 2001

1. ATT Conference Barcelona, October 1-3,2001 How to improve hybrid vehicles for environmental sustainability. A case study of their impact. Antonio MATTUCCI, Mario CONTE, Giovanni PEDEENEA – Advanced Energy Technologies Division C.R. Casaccia - Via Anguillarese 301 00060 Rome (Italy) V Incontro Expert Panel Emissioni da Trasporto su Strada

2. ENEA SPECIFIC ACTIVITIES IN TRANSPORT FIELD Among the ENEA interests in the transport field, special attention is paid to the vehicle efficiency and environmental impact; in particular with: • Realisation of integrated facilities to assist design and testing of electric and hybrid vehicles and specific components of the traction system • Fleet tests under operational conditions of hybrid vehicles • Fuel cells and H2 Program V Incontro Expert Panel Emissioni da Trasporto su Strada

3. Vehicle drivetrain integrated testing facility The main parts of the facility, interconnected each other in order to provide high test flexibility , are: • Power generation section • Energy storage section • Driving motors section • Integrated control room V Incontro Expert Panel Emissioni da Trasporto su Strada

4. Fleet test of hybrid vehicles Public transport fleets have been tested in three selected cities, where 24 IVECO 490 buses have been purchased and operated for 3 year (1997-1999) • 4 in Terni • 8 in Ferrara • 12 in Rome V Incontro Expert Panel Emissioni da Trasporto su Strada

5. Fleet test of hybrid vehicles • 2.8 l diesel engine • 30 kW DC electric generator • 164 kW AC electric motor • 60 kWh capacity lead acid batteries • 200-300 km range of in thermal mode and 20 km in pure electric mode • 60 km/h max speed • manual selection of driving mode IVECO 490 hybrid bus characteristics V Incontro Expert Panel Emissioni da Trasporto su Strada

6. Fleet test of hybrid vehicles Hybrid and conventional bus test results Need of a control system to increase hybrid vehicle efficiency V Incontro Expert Panel Emissioni da Trasporto su Strada

7. Hybrid vehicle control system framework • Series hybrid vehicle fuel consumption dependent on battery State Of Charge (SOC) and generator power • Test campaign to get additional information on hybrid specific consumption, using a purpose-designed series hybrid vehicle with the same driveline of 6m ALTROBUS • Control strategy constrains the battery SOC to stay in a selected interval and allows modifications of the thermal engine working point, with variations in a range of 20-25%, as in such interval the environmental and energetic efficiency remains high V Incontro Expert Panel Emissioni da Trasporto su Strada

8. Hybrid vehicle driveline characteristics Internal combustion engine • 1.2 l diesel engine • 24 kW max power (@ 3600 rpm) • 2200 rpm rating speed Synchronous PM Machine • 10 kW rating power (@ 2200 rpm) Storage system (battery) • 96 lead acid cells • 100 Ah capacity, 192 V V Incontro Expert Panel Emissioni da Trasporto su Strada

9. IVECO Daily hybrid vehicle layout V Incontro Expert Panel Emissioni da Trasporto su Strada

10. Hybrid vehicle DC source behaviour V Incontro Expert Panel Emissioni da Trasporto su Strada

11. Daily hybrid vehicle controller development • Low cost controller, 200 ms. sampling time • Step by step controller development • Final controller version based on a forecast of the power required (based on previous average power + trip route) • Controller algorithm processes data related to battery voltage, current and SOC • First controller version has no power forecast and requires manual setting of: generator power and SOC interval limits • Controller switches on-off the thermal engine to keep the battery SOC between predefined limits • Controller effectiveness verified by means of many tests based on European, American and Japanese cycles V Incontro Expert Panel Emissioni da Trasporto su Strada

12. Daily hybrid vehicle test results V Incontro Expert Panel Emissioni da Trasporto su Strada

13. Effectiveness of hybrid vehicle controller Testing on the vehicle has shown the following results: • Considerable improvement on fuel efficiency achieved, especially for the American cycle • Important to minimise start/stops of the thermal engine • Next step with thermal engine load prediction requires more sophistication for the control algorithm • Need to modify the thermal engine working point (power and speed) to gain additional efficiency • 30-40% of fuel consumption reduction achievable, with similar benefits in terms of pollutant emission reduction V Incontro Expert Panel Emissioni da Trasporto su Strada

14. Requirements for hybrid vehicle fleet deployment effectiveness analysis Main requirements • Identification of effective application domains, where hybrid vehicles can play a special role • Measurability of resulting effects at global scale • Different effects (such as pollutant emissions, fuel consumption and even the resulting traffic conditions) to be considered at the same time • Identification of economically and technically affordable deployment experiences • Identification of appropriate analysis tools in order to simulate the resulting scenario • Use of conservative assumptions where sound information is lacking V Incontro Expert Panel Emissioni da Trasporto su Strada

15. Initial considerations Light Duty Vehicles (LDVs) cover approximately 5% of the Italian fleet (2 millions of vehicles) LDVs cover the main share of freight transport in urban areas LDVs are responsible of relevant shares of pollutant emissions in urban areas Results of ENEA hybrid vehicle experimental test campaign fit perfectly LDVs behaviour TREMOVE model and reliable database are already available for a deployment study LDVs viability for hybrid vehicle fleet deployment application V Incontro Expert Panel Emissioni da Trasporto su Strada

16. Share of LDVs pollutant emission in Italian urban areas V Incontro Expert Panel Emissioni da Trasporto su Strada

17. Hybrid LDVs reduction factors for impact analysis V Incontro Expert Panel Emissioni da Trasporto su Strada

18. LDVs behaviour V Incontro Expert Panel Emissioni da Trasporto su Strada

19. LDVs behaviour V Incontro Expert Panel Emissioni da Trasporto su Strada

20. Hybrid LDVs urban deployment study • Milancity selected for the analysis • 142000 LDVs operating in Milan area • Introduction of hybrid LDVs begins in year 2002 • The shares of new hybrid LDVs covers 20% in the year 2002, 55% in 2003 and 100% in 2004 and beyond • Total extra-cost in 2002-2005 is about 174 MEuros, of which 12 in the year 2002 (2000 new LDVs deployed) • Two scenarios have been analysed with TREMOVE model, the first one only with hybrid introduction and the second one with also the integration of telematic systems to improve freight delivery effectiveness V Incontro Expert Panel Emissioni da Trasporto su Strada

21. Hybrid LDVs first scenario results • Comparison to reference basecase shows relevant differences only on emissions • Considerable effect specially on PM ( 5%) • After 2008 no more PM reduction as almost all the oldest and dirtiest LDVs have been removed V Incontro Expert Panel Emissioni da Trasporto su Strada

22. Hybrid LDVs second scenario results • Two beneficial effects, i.e. direct reduction of emissions and increase of commercial speed, respect to reference basecase • Relevant decrease of all the pollutants ( >5%) • Higher effects on fuel consumption, CO2 and CO emission V Incontro Expert Panel Emissioni da Trasporto su Strada

23. Conclusions • Fleet tests of hybrid vehicles have shown positive performances and provided information for the fields where additional research is required • Series hybrid vehicles can be improved by the adoption of a control system able to manage the battery SOC and the thermal engine working point • Series hybrid vehicles can provide good results for applications in domains where both the vehicle efficiency and emission reduction are to be considered • The combination of hybrid technology with other provisions (technological, legislative, informative, etc.) can provide very important additional benefits V Incontro Expert Panel Emissioni da Trasporto su Strada