Powertrain Optimisation supported by Simulation

Wolfgang Kriegler 한국자동차공학회 2000 한국자동차공학회 Workshop Vol.2000 No.-

The main intention of the lecture is to present a method for vehicle concept analysis as well as for new powertrain layout meant as a common optimisation of engine and drive train parameters. Furthermore the advantages and benefits using simulation techniques in the development of hybrid powertrains will be highlighted.<br/> After an introduction, an idealised computer aided development process for the entire powertrain is presented. It shows how state-of-the-art simulation techniques can contribute to a comprehensive, continuous development process, which is based upon off-line simulation, hardware in the loop simulation, the utilisation of modern test bed technology up to final vehicle calibration. The ultimate goal of this "simulation supported development process" is to optimise the entire powertrain, which has been, up to now, practically been designed from experience and mainly in experiments. Further to optimise the interaction between the individual components soon enough and to minimise prototype variations which is especially important with hybrid vehicles as there are theoretically so many possibilities to design a hybrid powertrain. In this context, the presentation does not focus on the development of such powertrain components but rather their design, assessment and parameterisation as well as the harmonisation of the single components. Especially with hybrids, the exact knowledge of the "mission" of the vehicle, the expected driving profile and the expected end-user related problems is necessary. Particular importance is also attached to powertrain controls i.e. the link between electronic engine, transmission and vehicle control units.<br/> Then more in detail some simulation modules such as engine models and transmission models are presented, which are essential modules for the development process mentioned above.<br/> After having introduced process and the necessary off-line and real-time simulation models of powertrain components, some basic consideration about hybrid powertrains are presented. Two hybrid examples are chosen to support the necessity for the use of simulation.<br/> In the first example the development of the AVL Universal Hybrid system is highlighted which has been simulation supported throughout the whole project period. The second expample shows results of the simulation supported analysis of the well known Toyota Prius hybrid vehicle. Based upon the described development methodology, it is evident that optimum development results can only be achieved by considering the total powertrain system. Especially for the high complex powertrain systems of hybrid vehicles the application of the new, simulation supported development processes is strongly recommended. The tools for it are available at AVL and are being continuously developed further. However the goal is to reduce development time and costs by the consequent realization of this presented process.

Locked into Copenhagen pledges - Implications of short-term emission targets for the cost and feasibility of long-term climate goals

Riahi, K.,Kriegler, E.,Johnson, N.,Bertram, C.,den Elzen, M.,Eom, J.,Schaeffer, M.,Edmonds, J.,Isaac, M.,Krey, V.,Longden, T.,Luderer, G.,Mejean, A.,McCollum, D.L.,Mima, S.,Turton, H.,van Vuuren, D.P. American Elsevier 2015 TECHNOLOGICAL FORECASTING AND SOCIAL CHANGE Vol.90 No.1

This paper provides an overview of the AMPERE modeling comparison project with focus on the implications of near-term policies for the costs and attainability of long-term climate objectives. Nine modeling teams participated in the project to explore the consequences of global emissions following the proposed policy stringency of the national pledges from the Copenhagen Accord and Cancun Agreements to 2030. Specific features compared to earlier assessments are the explicit consideration of near-term 2030 emission targets as well as the systematic sensitivity analysis for the availability and potential of mitigation technologies. Our estimates show that a 2030 mitigation effort comparable to the pledges would result in a further ''lock-in'' of the energy system into fossil fuels and thus impede the required energy transformation to reach low greenhouse-gas stabilization levels (450ppm CO<SUB>2</SUB>e). Major implications include significant increases in mitigation costs, increased risk that low stabilization targets become unattainable, and reduced chances of staying below the proposed temperature change target of 2<SUP>o</SUP>C in case of overshoot. With respect to technologies, we find that following the pledge pathways to 2030 would narrow policy choices, and increases the risks that some currently optional technologies, such as carbon capture and storage (CCS) or the large-scale deployment of bioenergy, will become ''a must'' by 2030.

The Shared Socioeconomic Pathways and their energy, land use, and greenhouse gas emissions implications: An overview

Riahi, Keywan,van Vuuren, Detlef P.,Kriegler, Elmar,Edmonds, Jae,O’Neill, Brian C.,Fujimori, Shinichiro,Bauer, Nico,Calvin, Katherine,Dellink, Rob,Fricko, Oliver,Lutz, Wolfgang,Popp, Alexander,Cuaresm Elsevier 2017 Global environmental change Vol.42 No.-

<P><B>Abstract</B></P> <P>This paper presents the overview of the Shared Socioeconomic Pathways (SSPs) and their energy, land use, and emissions implications. The SSPs are part of a new scenario framework, established by the climate change research community in order to facilitate the integrated analysis of future climate impacts, vulnerabilities, adaptation, and mitigation. The pathways were developed over the last years as a joint community effort and describe plausible major global developments that together would lead in the future to different challenges for mitigation and adaptation to climate change. The SSPs are based on five narratives describing alternative socio-economic developments, including sustainable development, regional rivalry, inequality, fossil-fueled development, and middle-of-the-road development. The long-term demographic and economic projections of the SSPs depict a wide uncertainty range consistent with the scenario literature. A multi-model approach was used for the elaboration of the energy, land-use and the emissions trajectories of SSP-based scenarios. The baseline scenarios lead to global energy consumption of 400–1200 EJ in 2100, and feature vastly different land-use dynamics, ranging from a possible reduction in cropland area up to a massive expansion by more than 700 million hectares by 2100. The associated annual CO<SUB>2</SUB> emissions of the baseline scenarios range from about 25 GtCO<SUB>2</SUB> to more than 120 GtCO<SUB>2</SUB> per year by 2100. With respect to mitigation, we find that associated costs strongly depend on three factors: (1) the policy assumptions, (2) the socio-economic narrative, and (3) the stringency of the target. The carbon price for reaching the target of 2.6W/m<SUP>2</SUP> that is consistent with a temperature change limit of 2°C, differs in our analysis thus by about a factor of three across the SSP marker scenarios. Moreover, many models could not reach this target from the SSPs with high mitigation challenges. While the SSPs were designed to represent different mitigation and adaptation challenges, the resulting narratives and quantifications span a wide range of different futures broadly representative of the current literature. This allows their subsequent use and development in new assessments and research projects. Critical next steps for the community scenario process will, among others, involve regional and sectoral extensions, further elaboration of the adaptation and impacts dimension, as well as employing the SSP scenarios with the new generation of earth system models as part of the 6th climate model intercomparison project (CMIP6).</P> <P><B>Highlights</B></P> <P> <UL> <LI> We present an overview of the Shared Socioeconomic Pathways (SSPs), which were developed as a community effort over the last years. </LI> <LI> The SSPs comprise five narratives and a set of driving forces. </LI> <LI> Our SSP scenarios quantify energy and land-use developments and associated uncertainties for greenhouse gas and air pollutant emissions. </LI> <LI> We conduct an SSP mitigation analysis, and estimate mitigation costs. We find that very low climate targets might be out of reach in SSPs featuring high challenges. </LI> <LI> The SSPs are now ready for use by the climate change research community. </LI> </UL> </P>

Biophysical and economic limits to negative CO₂ emissions

Smith, Pete,Davis, Steven J.,Creutzig, Felix,Fuss, Sabine,Minx, Jan,Gabrielle, Benoit,Kato, Etsushi,Jackson, Robert B.,Cowie, Annette,Kriegler, Elmar,van Vuuren, Detlef P.,Rogelj, Joeri,Ciais, Philipp Nature Publishing Group 2016 Nature climate change Vol.6 No.1

<P>To have a >50% chance of limiting warming below 2 degrees C, most recent scenarios from integrated assessment models (IAMs) require large-scale deployment of negative emissions technologies (NETs). These are technologies that result in the net removal of greenhouse gases from the atmosphere. We quantify potential global impacts of the different NETs on various factors (such as land, greenhouse gas emissions, water, albedo, nutrients and energy) to determine the biophysical limits to, and economic costs of, their widespread application. Resource implications vary between technologies and need to be satisfactorily addressed if NETs are to have a significant role in achieving climate goals.</P>