Low-carbon Road Research Articles

The possible future of electric road systems in Europe—time to decide and act

Electrification of road transport is crucial to limit global warming. Battery electric vehicles with stationary charging infrastructure have received considerable attention in the scientific literature for both cars and trucks, while dynamic charging via electric road systems (ERS) has received much less attention and their future role in low-carbon road transport is uncertain. Here, we envision three potential scenarios for the future of ERS in European low-carbon transport. We sketch a potential European ERS network and discuss the political, technological, and market steps needed to realize these. We argue that existing field trials, tests, and research projects have collected sufficient evidence to make the next step: Decide and act. Decision-makers will never have perfect information about all aspects of ERS or competing technologies, but the urgency of the climate crisis requires a commitment one way or the other. A clear decision with respect to ERS would send a clear directive and would help focus time, effort, and money on the necessary infrastructure and policies to implement ambitious GHG abatement targets in road transport.

Development of a framework to assess the greenhouse gas mitigation potential from the adoption of low-carbon road vehicles in a hydrocarbon-rich region

This study developed a novel assessment framework to analyze long-term energy transition in the road transport sector in which various technology options, market shares, policy measures, costs, and greenhouse gas emissions are considered in a single framework analysis. A data-intensive model was developed with the Low Emissions Analysis Platform (LEAP) and used to analyze policy scenarios up to 2050 for Alberta, Canada, a hydrocarbon-rich province with an emission-intensive energy sector. Three key policy measures – carbon pricing, zero-emission vehicle sales mandate, and incentivization – were analyzed in nine individual and combined policy scenarios. The transition to both hydrogen fuel cell electric vehicles and battery electric vehicles was assessed for all vehicle categories. Each fuel's full energy supply chain was modelled, including resource extraction, conversion, transmission and distribution, and fuelling, allowing for final and primary energy analysis. The findings show that carbon price and zero-emission vehicle incentives do not effectively lower greenhouse gas emissions on their own; zero-emission vehicle mandates are needed to transition the sector to a low-carbon energy system. The system-wide greenhouse gas emission footprints of hydrogen and battery electric vehicles are significantly below conventional vehicles in all cases. Scenarios biased towards battery electric vehicles had the most favorable results. The greenhouse gas emission footprint of hydrogen vehicles supplied by auto-thermal reforming with 91% carbon capture was lower than for battery electric vehicles powered by a primarily natural gas-based power grid. The findings on the effectiveness of carbon prices, incentives, and vehicle mandates should be considered by government policymakers aiming to reduce greenhouse gas emissions, infrastructure planners, and other energy stakeholders.

Comparative study for global warming potentials of Chinese and Norwegian roads with life cycle assessment

Mitigation of GHG emission is increasing concerned in the research field of road engineering. The quantitative assessments of integral road structural designs in different countries would shed light on the implementation of sustainable road development and global warming controlling. The study referred to the European E6 and the Yanqing-Chongli expressway to quantify the GHG emissions for Norwegian and Chinese roads, and investigate the critical procedures and factors in resulting in the differences of GHG emissions. The data inventory and research framework for life cycle assessment (LCA) were established according to their applied materials, structural design and construction techniques. Moreover, the quantification of GHG emission was conducted as considering the surface layers, base layers, subbase and frost protection layer. The comparative results indicate that the Norwegian road generated extra 1.43 t equivalent CO2 more than Chinese road during the 20-year service life, and the surface layers are the most source of GHG emission in road structure, which occupied 65.75% for Chinese road and 43.19% for Norwegian road. Additionally, the materials extraction phase caused the largest proportion of GHG emission in Chinese road case, while the road construction phase was verified as the capital GHG contributor in Norwegian road case with 108.27 t equivalent CO2 emitted. The obtained results in the comparative study could provide the practical references for low-carbon road construction and promising strategies for globalization development.

Carbon Emission Pattern of Driving Car on Vertical Curves of Highway

Low carbon road design has always been a research hotspot for scholars. One of the primary road variables affecting the carbon emission of automobiles is vertical curve, which serves as the primary geometric alignment of the longitudinal portion of the road. The instantaneous speed and acceleration data of cars on various vertical curve sections are gathered for this study by combining simulation and real vehicle experiment methods. This study then built a database of carbon emissions for cars on various vertical curve sections based on the Motor Vehicle Emission Simulator (MOVES) model, used Statistical Product and Service Solutions (SPSS) to analyze the data, and developed a carbon emission model for cars on various vertical curve sections. Finally, it was found that the average error of the carbon emission model for different vertical curve sections was 8.37%, and the accuracy of carbon emission modelling could meet the requirements. The results show that the main influencing factor of carbon emission of cars on vertical curve sections is the radius of vertical curve, and the carbon emission of cars is inversely proportional to the radius of vertical curve. The smaller the value of vertical curve radius is, the more the engine output increases and the greater the carbon emission level will be. This research will provide reference and theoretical support for low-carbon design of highway longitudinal slope sections.

Low-Carbon Road Reconstruction Design —— Empirical Research Based on Road Cost Management Software

Driven By the Low Carbon Policy, low-carbon road infrastructure construction is greatly concerned. The lack of standardized quantification of energy consumption and carbon emissions limits the universality of Low Carbon road construction practice. Based on the national road cost management software and China's life cycle core database, the standardized quantification method of energy consumption and carbon emissions is established. Empirical project data are used to check the Effectiveness of the method. The method is to screen out the design measure with better energy conservation and lower carbon emission.

Pricing carbon for a fair and effective low-carbon road transport transition in the EU

Implementing carbon pricing is essential to phase out conventional vehicles for achieving ambitious climate targets in road transport, but doing it in a socially fair way is challenging. The EU’s new system aims to addresse this challenge, but its design impairs effectiveness. Future ratcheting up requires strategic use of carbon price revenues to properly balance social compensation and green investments. Implementing carbon pricing is essential to phase out conventional vehicles for achieving ambitious climate targets in road transport, but doing it in a socially fair way is challenging. The EU’s new system aims to addresse this challenge, but its design impairs effectiveness. Future ratcheting up requires strategic use of carbon price revenues to properly balance social compensation and green investments.

Research on road transport planning aiming at near zero carbon emissions: Taking Ruicheng County as an example

The rapid development of the urban and rural transport sectors has increased focus on energy and the environment. To support the transport sector in its efforts to achieve carbon neutrality targets, low-carbon road transport planning for specific regions has become a necessity. Using Ruicheng County, Shanxi, China as an example, county-level planning of the road transport sector is conducted in terms of quantifying energy consumption and CO2 emissions; the applicable forms and economic costs of technologies including rooftop photovoltaics and smart chargers in different regions are also discussed. A bottom-up model is built and a scenario analysis is adopted to predict the effects of different policy measures by 2035. Under an aggressive scenario, the demand for fossil fuel will be reduced, while the electricity demand will increase. 91% of CO2 emissions can be reduced. The results show that measures including replacing conventional vehicles with electric vehicles and encouraging public transport could effectively facilitate the road transport sector to gradually approach zero carbon emissions. However, the consumption of diesel by agricultural vehicles is the greatest obstacle to achieving carbon neutrality. Electric vehicles and building-related charging infrastructure can potentially have an important role in the future transport sector and electricity systems.

Greenhouse gas emission benefits of adopting new energy vehicles in Suzhou City, China: A case study.

The promotion of new energy in light-duty vehicles (LDVs) is considered as an effective approach for achieving low-carbon road transport targets. In this study, life cycle assessment was performed for five typical vehicle models in Suzhou City (fourth largest LDV stock in China): internal combustion engine vehicle (ICEV), hybrid electric vehicle (HEV), plug-in electric vehicle (PHEV), battery electric vehicle (BEV) and hydrogen fuel cell vehicle (HFCV). Their energy consumption, and greenhouse gas (GHG) and air pollutant emissions during vehicle and fuel cycles in 2020 were examined using the Greenhouse gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. GHG emission reduction potential of LDV fleet was projected under various scenarios for 2021-2040. The results showed that BEVs exhibited advantages for replacing ICEVs over HEVs, PHEVs and HFCVs, taking into account China's road electrification policy. The GHG emission intensity of BEVs in 2040 was estimated to be 19-34% of ICEVs in 2020, with a deep decarbonized electricity mix and improved vehicle efficiency. For the aggressive Sustainable Development Scenario, the GHG emissions of LDVs would peak before 2026, ahead of China's target by 2030, and the ~ 100% share of EVs in 2040 would result in a lower GHG emissions, equivalent to the 2010 level. It highlights the importance of early action, green electricity mix, and public transport development in reducing GHG emissions of large LDV fleet.

CO2 Emission Reduction Potential of Road Transport to Achieve Carbon Neutrality in China

Under the targets of peaking CO2 emissions and carbon neutrality in China, it is a matter of urgency to reduce the CO2 emissions of road transport. To explore the CO2 emission reduction potential of road transport, this study proposes eight policy scenarios: the business-as-usual (BAU), clean electricity (CE), fuel economy improvement (FEI), shared autonomous vehicles (SAV), CO2 emission trading (CET) (with low, medium, and high carbon prices), and comprehensive (CS) scenarios. The road transport CO2 emissions from 2020 to 2060 in these scenarios are calculated based on the bottom-up method and are evaluated in the Low Emissions Analysis Platform (LEAP). The Log-Mean Divisia Index (LMDI) method is employed to analyze the contribution of each factor to road transport CO2 emission reduction in each scenario. The results show that CO2 emissions of road transport will peak at 1419.5 million tonnes in 2033 under the BAU scenario. In contrast, the peaks of road transport CO2 emissions in the CE, SAV, FEI, CET-LCP, CET-MCP, CET-HCP, and CS scenarios are decreasing and occur progressively earlier. Under the CS scenario with the greatest CO2 emission reduction potential, CO2 emissions of road transport will peak at 1200.37 million tonnes in 2023 and decrease to 217.73 million tonnes by 2060. Fuel structure and fuel economy contribute most to the emission reduction in all scenarios. This study provides possible pathways toward low-carbon road transport for the goal of carbon neutrality in China.

Shared Automated Electric Vehicle Prospects for Low Carbon Road Transportation in British Columbia, Canada

This study explores the long-term energy use implications of electrification, automation and sharing of road vehicles in British Columbia, Canada. Energy use is first analyzed for the years 1990–2016 for forward forecasting, and hypothetical scenarios ranging from conservative to disruptive, incorporating various effects of road vehicle electrification, sharing and automation, as well as influences of other technology disruptions, such as online shopping and e-learning are presented and used to project the road transportation energy use in B.C. to 2060. Transportation energy use projections are compared to those of the Canadian Energy Regulator (CER). When considering only the effect of vehicle electrification, the scenarios show higher energy savings compared to CER’s scenarios. The combined impact of vehicle electrification and automation leads to decreased energy use to 2060 for all scenarios considered. The energy savings for all scenarios, except for the conservative one, are higher than CER’s projections. When the effects of vehicle electrification, automation and sharing are merged, all scenarios yield energy savings beyond the CER projections. Inclusion of other technology disruptions and the effects of pandemics like COVID-19 reduce transportation demand and provide further energy savings. The BAU scenario given in this study shows energy use decreases compared to 2016 of 26.3%, 49%, 62.24%, 72.1% for the years 2030, 2040, 2050, and 2060 respectively.

The impact of China's low-carbon transition on economy, society and energy in 2030 based on CO2 emissions drivers

China has become the world's largest carbon dioxide emitter and energy consumer, with serious environmental problems. Therefore, low-carbon economy has become the best choice for its development. In this paper, the economy, society, energy and environment are taken into account to build a low-carbon economy system (LCE). It is used to analyze the drivers of CO2 emissions and impact of low-carbon transition in China. Bayesian network and scenario analysis are applied. The results show that the increase of per capita consumption expenditure, energy consumption per unit of GDP, energy consumption per capita and CO2 emissions per capita is the reason for the continuous growth of CO2 emissions; the improve of energy efficiency, CO2 emissions per unit of GDP and CO2 emissions per unit of energy consumption inhibits CO2 emissions. China's low-carbon development does not come at the expense of its economic growth. Actually, the low-carbon transition is accompanied by the growth of population, consumer spending, energy consumption and energy efficiency. Urbanization rate will be up to 75.70%–97.44%. Compared with 2017, energy efficiency increases by 4.51%; energy consumption per unit of GDP reduces by 0.4%. Transformation of energy subsystem is the key to a low-carbon road.

Assessment of the macro-economic impacts of low-carbon road transportation policies in Chongqing, China

Reductions in the transportation sector's carbon dioxide emissions are increasingly of global concern. As one of the first low-carbon pilot and carbon trading pilot cities, and as one of the largest automobile production bases in China, Chongqing has multiple low-carbon transportation policies that are coupled. In this study, three policy scenarios are set, including: 1) improving the fuel economy of newly sold gasoline passenger cars to 5.7 l per 100 km by 2020, 2) promoting pure electric private cars to increase the share to 7% of private car sales by 2020, and 3) the policy mix scenario of the above two policies. Simulations are undertaken with the Chinese Academy of Sciences general equilibrium (CAS-GE) model, a type of computable GE model, to assess the macro-economic impact and the industrial impact of the three policy scenarios. Through the policy impact mechanism analysis and data-mapping process, the micro-economic impact analysis results, including costs and fuel savings, for the two policies from the bottom-up model are taken as the shock variables and inputs for the CAS-GE model. The results show that: 1) the two policies will both have a slightly negative impact (−0.09% and −0.30%) on Chongqing's GDP in 2020; 2) the employment rate will decrease by 0.12% and 0.47%, but the inflation rate will be restrained to a certain extent (−0.21% and −0.17%); and 3) the complementarity of the mixed policy can weaken the negative impact of the two policies when implemented separately. The mixed policy will reduce the GDP slightly by 0.37%, compared with the cumulative effect of the two policies implemented separately, resulting in cost-effective synergies at the macro-economic impact level; and 4) the COVID-19 pandemic in 2020 has an uncertain impact on the results. The method and results can provide a reference for the formulation and adjustment of low-carbon transportation policies in other large cities.

Modelling carbon emissions of diesel trucks on longitudinal slope sections in China.

Carbon emissions are the primary reason that contributes to global warming. The gradient has a significant impact on the carbon dioxide (CO2) emissions produced by trucks. The aim of the current paper is to propose a carbon emission quantification model for diesel trucks on longitudinal slope sections and investigate the influence of gradient on the carbon emissions of trucks for use in the low-carbon highway design. The law of conservation of mechanical energy, the first law of thermodynamics, and the vehicle longitudinal dynamics theory were adopted for deriving the carbon emission model of the trucks on the flat, uphill, downhill and round-trip longitudinal slope segments. Three kinds of common trucks were chosen to conduct the field test. Following the test data, the model demonstrates a high accuracy. The minimum gradient which is expected to impact carbon emissions of trucks on the round-trip longitudinal slope sections was the balance gradient as revealed. The gradient of the longitudinal slope is required to be avoided to be greater in comparison with the balance gradient for the achievement of the two-way traffic low carbon operation on a highway. The results of this study are valuable to researchers interested in low carbon road design and low carbon transportation control.

The energy transition in transport using alternative fuels: Can new technologies achieve policy targets?

AbstractCOP21 resulted in a major global agreement to reduce greenhouse gas emission to limit the Earth’s rising temperature to <2°C. Transport has a key role in the transition to a clean low carbon energy system. The aim of this work was to develop optimum scenarios for the implementation of alternative low carbon road transport fuels to replace conventional fuels of gasoline and diesel using the systems analysis model MESSAGE. The results show that technological breakthroughs to enhance efficiency and cost reduction of solar fuels will enable them to compete with gasoline and diesel in meeting the demand for road transport fuels. It also found that that production of synthetic fuels can significantly contribute to reducing consumption of crude oil while reducing CO2 emission by 80 per cent by 2050. Compared with previous literature, our work considers synfuels from fossil fuels can compete with biomass‐derived fuels, and it shows potential transition scenarios in the road transport sector to replace gasoline and diesel in fossil fuel‐dependent economies considering Saudi Arabia as a case study. Solar fuels appear as the most promising for reducing emission, albeit at a high price. Carbon abatement costs are found to range between $121 and $517/Ton, between 2015 and 2050. Feasible implementation of solar and synthetic fuels was also found to depend on the targeted CO2 emission, fuel efficacy, penetration of public transport and economic growth.

Toward Sustainable and Low Carbon Road Transportation: Policies, Tools, and Planning Methods

The road sector is the dominant transport mode in terms of demand for both passengers and goods [...]

Agent Based Models to Understand Diffusion of Low Carbon Road Transport Technologies: A Review of Application and Approaches

The transportation sector accounts for the largest consumption of non-renewable energy globally, highlighting the need for a broader understanding of alternative paths towards mitigating this status. Technological advancement is on the rise and with increasing policy support, studies present diverse approaches on evaluation of policy mix options to stimulate adoption of these technologies. Of interest to this paper is the agent-based modelling (ABM) approach, which is a methodology that integrates dynamics of behavioural decisions that are largely exhibited in several aspects of transport activities and the energy system. In this regard, we review ABM studies that investigate opportunities for alternative low carbon road transport technologies. In general, the literature shows a large presence of ABM application to transport related studies, with many finding opportunities for diffusion of alternative fuel vehicles (AFVs). However, most of the studies in literature neglect to explore the emissions savings implications, which is important, as it provides a scale to compare emissions savings by fuel/vehicle technology type, while providing more convincing findings for transport policy makers through quantitative indicators. Studies that encompass ABM application to AFVs and its emissions implications are quite limited. A systematic literature search resulted in identification of only 7 relevant articles in this regard. Findings suggest research gaps in AFV-ABM studies with opportunity for a model that integrates emissions measure and savings.

Influencing Factors and Scenario Forecasts of Carbon Emissions of the Chinese Power Industry: Based on a Generalized Divisia Index Model and Monte Carlo Simulation

The power industry is the industry with the most direct uses of fossil fuels in China and is one of China’s main carbon industries. A comprehensive and accurate analysis of the impacts of carbon emissions by the power industry can reveal the potential for carbon emissions reductions in the power industry to achieve China’s emissions reduction targets. The main contribution of this paper is the use of a Generalized Divisia Index Model for the first time to factorize the change of carbon emissions in China’s power industry from 2000 to 2015, and gives full consideration to the influence of the economy, population, and energy consumption on the carbon emissions. At the same time, the Monte Carlo method is first used to predict the carbon emissions of the power industry from 2017 to 2030 under three different scenarios. The results show that the output scale is the most important factor leading to an increase in carbon emissions in China’s power industry from 2000 to 2015, followed by the energy consumption scale and population size. Energy intensity levels have always promoted carbon emissions reduction in the power industry, where energy intensity and carbon intensity effects of energy consumption have great potential to mitigate carbon levels. By setting the main factors affecting carbon emissions in the future three scenarios, this paper predicts the carbon emissions of China’s power industry from 2017 to 2030. Under the baseline scenario, the maximum probability range of the potential annual growth rate of carbon emissions by the power industry in China from 2017 to 2030 is 1.9–2.2%. Under the low carbon scenario and technological breakthrough scenario, carbon emissions in China’s power industry continue to decline from 2017 to 2030. The maximum probability range of the potential annual drop rate are measured at 1.6–2.1% and 1.9–2.4%, respectively. The results of this study show that China’s power industry still has great potential to reduce carbon emissions. In the future, the development of carbon emissions reduction in the power industry should focus on the innovation and development of energy saving and emissions reduction technology on the premise of further optimizing the energy structure and adhering to the low-carbon road.

Scenario Analysis of Urban Road Transportation Energy Demand and GHG Emissions in China—A Case Study for Chongqing

This study, using Chongqing City of China as an example, predicts the future motor vehicle population using the Gompertz Model and the motorcycle population using the piecewise regression model, and predicts and analyzes fuel consumption and greenhouse gas (GHG) emissions of motor vehicles from 2016 to 2035 based on the bottom-up method under different scenarios of improving the fuel economy of conventional vehicles, promoting alternative fuel vehicles, and the mixed policy of the above two policy options. The results indicate that the total population of motor vehicles in Chongqing will increase from 4.61 million in 2015 to 10.15 million in 2035. In the business-as-usual scenario, the road-transportation energy demand in Chongqing will keep increasing from 2015 and will peak in 2030, before it begins to decline by 2035. The trends for the tank to wheel (TTW) and well to wheel (WTW) GHG emissions are similar to that of energy demand. The WTW GHG emissions will increase from 24.9 Mt CO2e in 2016 to 50.5 Mt CO2e in 2030 and will then gradually decline to 48.9 Mt CO2e in 2035. Under the policy scenarios of improving fuel economy of conventional fuel passenger cars, promoting alternative fuel vehicles, and their mixed policy, direct energy consumption and TTW and WTW GHG emissions from 2016 to 2035 will be reduced to different levels. It is also found that the two types of policies have a hedging effect on the direct energy-consumption saving, TTW, and WTW GHG emission reductions. Sensitivity analysis of key parameters and policy settings is conducted to investigate the impact of their changes on the vehicle population projection, direct energy demand, and WTW GHG emissions. Some policy implications are suggested to provide reference for the formulation and adjustment of Chongqing’s, or even China’s, low-carbon road transportation policies in the future based on the analysis results.

Innovation, pathways and barriers in Spain and beyond: An integrative research approach to the clean energy transition in Europe

To meet the goals of the Paris Agreement, as well as earlier targets set down in the EU Low-Carbon Road Map, requires a major transformation in the way energy is generated, marketed, and distributed that we call the clean energy transition. The clean energy transition is a social process and its success will be determined by the actions of key actors such as policy makers, energy suppliers and businesses. In this paper, we apply integrative research approaches to engage stakeholders in the renewable energy (RE) sector in knowledge co-construction activities for the case of Spain. Established modes of energy production are very resilient and powerful actors are effectively blocking the energy transition on the basis that it threatens the status quo. Innovation is unlikely unless that veto can be overcome. The work has implications elsewhere, especially for other EU countries, where institutional structures and power relations are similar to those in Spain. To move forward requires a better understanding of the clean energy transition as a social process, and in particular, systematic identification of barriers to innovation and a serious effort to negotiate with the most powerful players.

Exploring low carbon transition pathways for the UK road transport sector

ABSTRACTThis paper uses an analytical framework of multi-level and multi-phase perspectives to explore low carbon transition pathways for the UK road transport system. The work draws on the impact made by the national (UK) and regional (EU) low carbon policy instruments on the UK road sector. The results show that the transformation pathway, which is at the take-off phase on a large scale, is the only fully active pathway. The transformation is mainly characterized by the adoption of biofuel blends and hybrid electric vehicles, as well as niche technologies. For the emergence of an ideal low carbon road system in the UK, it is shown that the transformation pathway is insufficient and the likely pathway sequence to full decarbonization will be transformation-substitution-de-alignment/re-alignment. However, the dynamics that can favour a smooth process of this sequence will demand a range of active niche technologies and strong government intervention.