Energy-efficient Transportation Systems Electric Propulsion Systems for Busses Diesel-Electric / Hydrogen / Battery Busses Chicago, 05/13/2014 Dr.-Ing. Thoralf Knote Fraunhofer Institute for Transportation and Infrastructure Systems IVI
Fraunhofer IVI Applied research and development in the field of innovative transportation systems Electric Mobility Vehicle and Transport System Engineering Passenger Information and Electronic Ticketing Logistics
Electric Mobility A Core Strategy of the German Government - Independence from fossil fuels - Climate protection - Strengthening of the German economy
Electric Mobility A Core Strategy of the German Government - Various support programmes - Not focussed on one technology
Electric Mobility Why Busses? Pre-defined routes and schedules, which allow - the adaptation of core technologies to the routes, - recharging during operation, - the use of innovative energy and power management strategies for high energy efficiency.
Suitable Propulsion Technologies - Hydrogen busses - Hybrid busses - Trolleybusses (with or without energy storage) - Battery busses (busses with energy storage as sole energy source)
Hydrogen Busses - MAN Hydrogen ICE busses - 14 busses tested in Berlin - low reliability - cost and production of hydrogen (efficiency factor) problematic - MAN has stopped the production Source: TU International
Hydrogen Busses - Daimler fuel cell busses - three generations tested in Hamburg - significant technical improvements - still too expensive - currently not available Source: Lars Brüggemann - APTS / Vossloh Kiepe / HOPPECKE fuel cell busses - two vehicles currently tested in Cologne - Development of key technologies for battery busses
Hybrid Busses A New Operational Approach - Currently approx. 280 hybrid busses in operation - German companies deliver busses and key technologies Source: PE International Source: Rolf Schreiter
Hybrid Busses A New Operational Approach - Hybrid busses require certain route characteristics for significant fuel savings. - Not universally deployable - Still very expensive - Bridging technology? Source: DVB AG
Trolleybusses An Old-Fashioned Technology? - Mature technology with a new face - Hybrid trolleybusses offer new operational concepts: - partially catenary free operation - lines up to 65% catenary free. - German companies deliver key components Source: TrolleyMotion
Battery Busses The Next Challenge Battery busses must adapt to the operational requirements, not vice versa! - up to 350 km per day - no return to the bus depot in between - short dwell times at bus stops and short turn-around times
Battery Busses The Next Challenge - Battery busses still require a detailed energy demand analysis for each line: - energy demand vs. - storable energy and - rechargeable energy
Battery Busses The Next Challenge - Key technologies for battery busses in R&D: - energy storage systems - energy transfer into the bus - energy efficient auxiliaries (DC link voltage level) - energy efficient HVAC systems - Several European and national R&D support programmes
Battery Busses The Next Challenge - Energy storages: - several German suppliers - still insufficient energy density and life time - still too expensive but cost reduction potentials exist
Battery Busses The Next Challenge - Energy transfer systems: - necessary for lines with high energy demand - as few as possible actuators but high flexibility - Schunk Smart Charging
Thank you for your attention! Dr.-Ing. Thoralf Knote Fraunhofer Institute for Transportation and Infrastructure Systems IVI Zeunerstr. 38, 01069 Dresden, Germany Phone: +49/351/4640628 thoralf.knote@ivi.fraunhofer.de www.ivi.fraunhofer.de