Trends in on-road transportation, energy, and emissions

Modeling heterogeneous dynamic interactions among energy investment, SO2 emissions and economic performance in regional China

Massive investments in energy industry may either promote or mitigate the air pollution which is likely to influence the economic performance. In light of this, the current work is an empirical examination of heterogeneous dynamic causal interactions among energy investment, sulphur dioxide (SO₂) emissions and economic growth in regional China. A modified STIRPAT model is developed to introduce energy investment as a determinant of technology. Based on a modified model, a simultaneous equations system has been established to examine the three-way causal interactions among the variables of interest. As a first step, an error-correction-based second generation Westerlund (Oxford Bulletin of Economics and Statistics 69: 0305-9049, (2007). cointegration has been employed and found the long-run relationship. The simultaneous equations have been estimated by employing second generation dynamic common correlated effects mean group estimator (DCCEMGE) for 30 Chinese provinces and cities from 2001 to 2017. The empirical analysis has revealed that the energy investment induces emissions promotion effect while economic growth introduces emissions curtailment effect. However, the emissions curtailment effect remained slightly stronger than emissions promotion effect both at country and regional levels. Further, the energy investment growth uncovered economic performance enhancement effect. Furthermore, the SO₂ emissions growth induced economic performance deterioration effect. In this regard, the economic performance deterioration effect exceeded the economic performance enhancement effect. Besides, there is a bidirectional causality operative between SO₂ emissions and gross regional product (GRP) growth for the country as well as regional samples. On the contrary, a positive bilateral causal relationship between energy investment and GRP growth is found for the country as well as regional samples. Similarly, it has been found that there exists a positive bilateral causal association between SO₂ emissions and energy investment. Graphical abstract.

Holding the keys to health? A scoping study of the population health impacts of automated vehicles

Background

Automated Vehicles (AVs) are central to the new mobility paradigm that promises to transform transportation systems and cities across the globe. To date, much of the research on AVs has focused on technological advancements with little emphasis on how this emerging technology will impact population-level health. This scoping study examines the potential health impacts of AVs based on the existing literature.

Methods

Using Arksey and O’Malley’s scoping protocol, we searched academic and ‘grey’ literature to anticipate the effects of AVs on human health.

Results

Our search captured 43 information sources that discussed a least one of the five thematic areas related to health. The bulk of the evidence is related to road safety (n = 37), followed by a relatively equal distribution between social equity (n = 24), environment (n = 22), lifestyle (n = 20), and built environment (n = 18) themes. There is general agreement that AVs will improve road safety overall, thus reducing injuries and fatalities from human errors in operating motorized vehicles. However, the relationships with air quality, physical activity, and stress, among other health factors may be more complex. The broader health implications of AVs will be dependent on how the technology is adopted in various transportation systems. Regulatory action will be a significant determinant of how AVs could affect health, as well as how AVs influence social and environmental determinants of health.

Conclusion

To support researchers and practitioners considering the health implications of AVs, we provide a conceptual map of the direct and indirect linkages between AV use and health outcomes. It is important that stakeholders, including public health agencies work to ensure that population health outcomes and equitable distribution of health impacts are priority considerations as regulators develop their response to AVs. We recommend that public health and transportation officials actively monitor trends in AV introduction and adoption, regulators focus on protecting human health and safety in AV implementation, and researchers work to expand the body of evidence surrounding AVs and population health.

Emission Factors of a Euro VI Heavy-duty Diesel Refuse Collection Vehicle

Modern (Euro VI) heavy-duty vehicles have significantly lower pollutant emissions than older vehicles. However, there are still concerns regarding the emissions of refuse collection vehicles in cities, because in some cases they may use engines designed for long haulage trucks. For this reason, we tested a diesel Euro VI (step C) refuse collection heavy-duty vehicle, both in the laboratory on a chassis dynamometer and on the road, similar to the regulated in-service conformity cycle, but also with actual refuse collection cycles. Particle number (PN) and gaseous pollutants (NOx, CO, HC) were measured using a Portable Emissions Measurement System (PEMS). Additionally, in the laboratory we used laboratory grade gaseous, particle number, and FTIR (Fourier-transform infrared spectroscopy) systems to assess the PEMS. For short periods, where the exhaust gas temperature was low for the aftertreatment devices (cold start, some city conditions), the NOx emissions reached 2000 mg/km. Nevertheless, all pollutants were well below the applicable emissions limits expressed in mg/kWh for all cycles examined (in brackets the ratio to the laboratory limit): NOx < 400 mg/kWh (0.87), CO < 850 mg/kWh (0.21), HC < 12 mg/kWh (0.08), PN < 2.4×1010 p/kWh (0.04). To make sure that this will always be the case, future heavy-duty type approval emissions regulations should specifically consider the urban conditions for municipality vehicles, such as refuse trucks.