Pathways to Carbon-Free Transport in Germany until 2050

The transport sector has to be widely decarbonized by 2050 to reach the targets of the Paris Agreement. This can be performed with different drive trains and energy carriers. This paper explored four pathways to a carbon-free transport sector in Germany in 2050 with foci on electricity, hydrogen, synthetic methane, or liquid synthetic fuels. We used a transport demand model for future vehicle use and a simulation model for the determination of alternative fuel vehicle market shares. We found a large share of electric vehicles in all scenarios, even in the scenarios with a focus on other fuels. In all scenarios, the final energy consumption decreased significantly, most strongly when the focus was on electricity and almost one-third lower in primary energy demand compared with the other scenarios. A further decrease of energy demand is possible with an even faster adoption of electric vehicles, yet fuel cost then has to be even higher or electricity prices lower.

Review on Integrated On-Board Charger-Traction Systems: V2G Topologies, Control Approaches, Standards and Power Density State-of-the-Art for Electric Vehicle

This article reviews the different topologies compatible with V2G feature and control approaches of integrated onboard charger (iOBC) systems for battery electric vehicles (BEVs). The integrated topologies are presented, analyzed, and compared in terms of component count, switching frequency, total harmonic distortion (THD), charging and traction efficiencies, controllability, reliability and multifunctionality. This paper also analyzes different control approaches for charging and traction modes. Moreover, the performance indices such as setting time, rise time, overshoot, etc., are summarized for charging and traction operations. Additionally, the feasibility of a Level 3 charging (AC fast charging with 400 Vac) of up to 44 kW iOBC is discussed in terms of converter efficiencies with different switching frequencies and switch technologies such as SiC and GaN. Finally, this paper explores the power density trends of different commercial integrated charging systems. The power density trend analysis could certainly help researchers and solution engineers in the automotive industry to select the suitable converter topology to achieve the projected power density.

Vehicle Model-Based Driving Strategy Optimization for Lightweight Vehicle

In this paper, driving strategy optimization for a track is proposed for an energy efficient battery electric vehicle dedicated to the Shell Eco-marathon. A measurement-based mathematical vehicle model was developed to simulate the behavior of the vehicle. The model contains complicated elements such as the vehicle’s cornering resistance and the efficiency field of the entire powertrain. The validation of the model was presented by using the collected telemetry data from the 2019 Shell Eco-marathon competition in London (UK). The evaluation of applicable powertrains was carried out before the driving strategy optimization. The optimal acceleration curve for each investigated powertrain was defined. Using the proper powertrain is a crucial part of energy efficiency, as the drive has the most significant energy demand among all components. Two tracks with different characteristics were analyzed to show the efficiency of the proposed optimization method. The optimization results are compared to the reference method from the literature. The results of this study provide an applicable vehicle modelling methodology with efficient optimization framework, which demonstrates 5.5% improvement in energy consumption compared to the reference optimization theory.

Sustainable Public Transport Strategies—Decomposition of the Bus Fleet and Its Influence on the Decrease in Greenhouse Gas Emissions

The COVID pandemic has caused a major exodus of passengers who chose urban and suburban transport. In many countries, especially in the European Union, there is a tendency to choose individual means of transport, causing damage to the environment and contributing significantly to greenhouse gas emissions. One method to promote urban transport is replacing bus fleets with newer ones, thus making public transport more attractive and reducing the emission of harmful exhaust fume components into the atmosphere. The aim of this study was to show a methodology for calculating CO2e for bus fleets. When determining CO2e, the principal greenhouse gases, such as CO2, CH4, and N2O, are usually considered. However, CO emissions also have indirect effects on climate through enhanced levels of tropospheric O3 and increased lifetime of CH4;therefore, CO2, CH4, N2O, and CO emissions were determined for CO2e emission calculations. Two bus fleet variant scenarios were analysed;the first non-investment variant assumed passenger transport using the old fleet without any P&R parking zones. The second scenario was based on the current state, which includes the purchase of new low-emission buses and the construction of P&R infrastructure. The calculations were performed using the COPERT emission model with real data from 52 buses running on 13 lines. For the analysed case study of the Rzeszow agglomeration and neighbouring communes, implementing the urban and suburban transport modernisation project resulted in a reduction in estimated CO2e emissions of about 450 t. The methodology presented, which also considers the impact of CO emissions on the greenhouse effect, is a new element of the study that has not been presented in previous works and may serve as a model for other areas in the field of greenhouse gas emission analyses. The future research scope includes investigation of other fuels and powertrain supplies, such as hydrogen and hybrid vehicles.

Experimental Tests on a Spoke-Type Permanent Magnets Synchronous Machine for Light Electric Vehicle Application

Featured ApplicationLight electric vehicles propulsion.In an attempt to limit the effects of global warming, virtually all car manufacturers have introduced in the last years Hybrid or full Electric Vehicles. The current study shows the experimental testing of a spoke-type PMSM that was developed based on the requirements of the L6e European light vehicle class. A test bench was developed for this purpose, using a DC machine fed by a bidirectional DC Power Supply that allowed the testing of the PMSM prototype both in motor and generator/brake regimes. The Worldwide Harmonized Light-Duty Vehicles Test Procedure (WLTP) was implemented on the control stage of the testing set-up, allowing an accurate estimation of the PMSM-based E-drivetrain performance. The test results validated the FEM-simulated results and provided an insight on the efficiency of the entire drive system (battery–inverter–PMSM) and the autonomy of the L6e light EV. The electric drive system was integrated and tested on a prototype vehicle in normal operating conditions, validating the results obtained on the developed test bench.

Are Sustainable Aviation Fuels a Viable Option for Decarbonizing Air Transport in Europe? An Environmental and Economic Sustainability Assessment

The use of drop-in capable alternative fuels in aircraft can support the European aviation sector to achieve its goals for sustainable development. They can be a transitional solution in the short and medium term, as their use does not require any structural changes to the aircraft powertrain. However, the production of alternative fuels is often energy-intensive, and some feedstocks are associated with harmful effects on the environment. In addition, alternative fuels are often more expensive to produce than fossil kerosene, which can make their use unattractive. Therefore, this paper analyzes the environmental and economic impacts of four types of alternative fuels compared to fossil kerosene in a well-to-wake perspective. The fuels investigated are sustainable aviation fuels produced by power-to-liquid and biomass-to-liquid pathways. Life cycle assessment and life cycle costing are used as environmental and economic assessment methods. The results of this well-to-wake analysis reveal that the use of sustainable aviation fuels can reduce the environmental impacts of aircraft operations. However, an electricity mix based on renewable energies is needed to achieve significant reductions. In addition, from an economic perspective, the use of fossil kerosene ranks best among the alternatives. A scenario analysis confirms this result and shows that the production of sustainable aviation fuels using an electricity mix based solely on renewable energy can lead to significant reductions in environmental impact, but economic competitiveness remains problematic.

Network Delay Modelling and Optimization of Internet-Based Distributed Test Platform for Fuel Cell Electric Vehicle Powertrain System

The accelerated global progress in the research and development of automobile products, and the use of new technologies, such as the Internet, cloud computing and big data, to coordinate development platforms in different regions and fields, can reduce the duration and cost of development and testing. Specifically, in the context of the current coronavirus disease (COVID-19) pandemic, which has caused great obstacles to normal logistics and transportation, personnel exchanges and information communication, platforms that can support global operation are significant for product testing and validation, because they eliminate the need for the transportation of personnel and equipment. Therefore, the establishment of a distributed test and validation platform for automotive powertrain systems, which can integrate software and hardware testing, is important in terms of both scientific research and industrialization. The main technical difficulties associated with such test and validation platforms include data transmission and the control of the transmission effect. A distributed test and validation platform for a fuel cell electric vehicle powertrain system is proposed herein. The two-time-scale Markov chain is used to simulate the delay between two places (China and Germany), and the least-squares support vector machine (LSSVM) method is used to optimize the transmission effect. The results show that the two-time-scale Markov chain model can effectively simulate the delay between two nations, and that its probability distribution is close to the measured value. The LSSVM method is effectively optimized for all four indicators (velocity, fuel cell output power, battery output power and electric motor output torque). This method can be effectively used in the remote development test validation of vehicle powertrain system. © 2021 SAE Technical Papers. All rights reserved.