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To achieve net zero emissions, the global transportation sector needs to reduce emissions by 90% from 2020 to 2050, and road freight has a significant potential to reduce emissions. In this context, emission reduction paths should be explored for road freight over the fuel life cycle. Based on panel data from 2015 to 2020 in China, China's version of the GREET model was established to evaluate the impact of crude oil mix, electricity mix, and vehicle technology on China's reduction in road freight emissions. The results show that the import share of China's crude oil has increased from 2015 to 2020, resulting in an increase in the greenhouse gas (GHG) emission intensity of ICETs in the well-to-tank (WTT) stage by 7.3% in 2020 compared with 2015. Second, the share of China's coal-fired electricity in the electricity mix decreased from 2015 to 2020, reducing the GHG emission intensity of battery electric trucks (BETs), by approximately 6.5% in 2020 compared to 2015. Third, different vehicle classes and types of BETs and fuel cell electric trucks (FCETs) have different emission reduction effects, and their potentials for energy-saving and emission reduction at various stages of the fuel life cycle are different. In addition, in a comparative study of vehicle technology, the results show that (1) for medium-duty trucks (MDTs) and heavy-duty trucks (HDTs), FCETs have lower GHG emission intensity than BETs, and replacing diesel-ICETs can significantly reduce GHG emissions from road freight; (2) for light-duty trucks (LDTs), BETs and FCETs have the highest GHG emission reduction potential; thus, improving technologies such as electricity generation, hydrogen fuel production, hydrogen fuel storage, and transportation will help to improve the emission reduction capabilities of BETs and FCETs. Therefore, policymakers should develop emission standards for road freight based on vehicle class, type, and technology., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

More stringent standards for engines and fuels are progressively implemented as alternatives to reduce on-road vehicle emissions. While electric vehicles appear as a perfect alternative since their engines do not emit pollutants, wear and dust resuspension (W&R) and indirect emissions associated with electricity production remain significant sources of pollution. This work compares well-to-wheel emissions (WTW) and abatement strategies for various types of passenger vehicles in Bogotá and Santiago for different pollutants (CO, PM 2.5 , SO 2 , and NOx) and greenhouse gases like CO 2 equivalent (CO 2 -Eq). Results show that WTW baseline emissions are more extensive in Bogotá than in Santiago (i.e., 58 and 30% for PM 2.5 and CO 2 -Eq), mainly due to the higher vehicle activity and older state of Bogotá's fleet. We also evaluated extreme scenarios to assess the potential of a given vehicle technology or energy source to reduce emissions. We assessed, in particular, the replacement of all current vehicles by (1) conventional technologies with stricter emission standards and (2) battery electric vehicles powered with different energy resources. Our results indicate that replacing the current fleet with modern combustion technologies has a lower reduction potential than battery electric vehicles, but these reductions largely depend on the energy mix. Substitution by electric vehicles powered with electricity from renewable energies is the most efficient scenario in both cities. Finally, results also stress the importance of the resuspension of deposited road dust and brake and tire wear emissions in both cities as a crucial source of PM 2.5 , which must be better controlled., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aims: Foods and drinks are major contributors (17%) to the greenhouse gas (GHG) emissions caused by private consumption in Europe. The carbon footprint (CF) of a certain product expresses the total GHG emissions over its whole life cycle, and its calculation for foodstuff is a necessary first step to reduce their contribution to global warming. The calculation of the CF of Maltese food products is especially relevant for two reasons: the economic characteristics of the island, whose food sector is highly dependent on imports, implying longer transport distances; and the Maltese electricity production mix, based almost exclusively on oil combustion., Methods and Results: The CF of ten multi-fruit juices marketed in Malta has been determined, covering all the processes from the agricultural stage to the distribution of the final products. As a functional unit (FU), a 250 ml bottle of packaged product arriving at the retailer has been considered. The Maltese orange juice, the only final product in which only local ingredients are used, presents the lowest CF (0.50 kgCO 2 /FU), while the remaining ones range from 0.67 kgCO 2 /FU to 0.80 kgCO 2 /FU. The major contributor to all the CFs is juice processing at the Maltese plant (0.42 kgCO 2 /FU), mainly due to the use of electricity (78%)., Conclusions: The influence of both the electricity mix and the Maltese supply chain in the CF of the final products has been demonstrated. Alternatives to reduce the impacts of the final products have been proposed and evaluated that could lower the average CF of the juices by 32%., Significance and Impact of the Study: The calculation of the CF of Maltese juices represents an innovative case study due to the characteristics of the island, and it is expected to act as a first step to lower their environmental impacts., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Quantifying greenhouse gas (GHG) emissions from electricity consumption presents a significant challenge due to the variable nature of the generation mix throughout the year and the complex dynamics of cross-border electricity trade. In this paper, we introduce an innovative methodology designed to accurately capture the hourly GHG emissions linked to electricity imports, and thus electricity consumption. Contrary to conventional approaches, our methodology identifies the relevant generation technologies in exporting countries which are activated for export. This selection is based on (i) the classification of the technologies according to their dispatch cost (merit order), and (ii) considers trade mechanisms from economic theory. We apply this methodology to Switzerland, a country characterized by a low-carbon electricity generation mix, which however heavily relies on imports from neighbouring countries, particularly during the winter months. Over the period from 2017 to 2021, we find that 88 % of Switzerland's domestic electricity demand is met by its own generation—primarily hydro and nuclear—while the remaining 12 % is imported, mainly from fossil-fuel-based sources. Consequently, the average annual GHG emission factor for electricity consumption in Switzerland is 98 g-CO2eq/kWh, with 29 % attributed to domestic generation and 71 % to imports. This figure is 40 % higher than the 70 g-CO2eq/kWh estimated using a conventional approach, which typically underestimates the specific impacts of electricity imports. The disparity between these approaches becomes even more pronounced when considering the seasonal and hourly variations in the electricity mix and the resulting emission factors. These insights are particularly crucial in the context of emerging electricity demands, such as heat pumps and electric vehicles, where accurate GHG accounting can significantly influence policy and investment decisions. • Novel methodology for computing hourly GHG emissions of grid electricity by integrating trade dynamics. • Method reveals significant emissions variations which are often overlooked in traditional approaches. • Provides CO2 signal for Swiss consumers to assess electricity impacts, crucial for heat pumps and EVs. [ABSTRACT FROM AUTHOR]

Ground-coupled heat pump (GCHP) systems can provide comfortable indoor environments, but also inevitably contribute to greenhouse gas emissions and other impacts on human health, ecosystems, and resources. Life cycle assessment (LCA) methodology has been widely adopted to estimate the environmental impacts associated with GCHP systems, with operational electricity consumption being the largest contributor among most categories. Given the data-intensive nature of LCA, operational electricity consumption should be prioritised to refine the accuracy of LCA results. Previous studies, however, have relied on static COP (Coefficient of Performance) and annual average data to obtain the environmental impacts and have disregarded the effect of long-term performance degradation caused by building thermal load imbalances. In this paper, to bridge this research gap, a dynamic operational environmental impact assessment (DOEIA) method was proposed to improve the precision of LCA results by incorporating higher temporal resolution data of electricity mix and real-time performance modelling of the reversible GCHP system. Impacts of different temporal resolutions (i.e. monthly, trimestral, and annual) on the accuracy of LCA results was examined and the operational performance degradation resulting from imbalanced building heating and cooling loads was considered. Results demonstrate that while performance degradation effects are evenly distributed across impact categories, gaps due to temporal resolutions vary significantly between different categories. Subsequent analysis of spatial variations in the latter further emphasises the importance of accounting for higher temporal resolutions. Finally, life cycle impact assessment (LCIA) results for reversible GCHP systems in different locations were obtained with the support of DOEIA method and the results underscore the necessity of a cleaner energy mix. The proposed DOEIA method can be applied to other energy systems for comparative analyses. It is replicable in other countries and regions and therefore is expected to provide methodological guidance for future decision-makers. • Development of a dynamic method to improve the accuracy of LCA of GCHP systems. • Evaluated long-term performance degradation and low-temporal resolution data effects. • Performance degradation affects categories consistently; low-resolution data varies. • Spatial analysis clarifies parameters affecting environmental impacts. • The proposed method is applicable to other energy systems for comparative analyses. [ABSTRACT FROM AUTHOR]

Purpose: An estimation of the environmental impact of buildings by means of a life cycle assessment (LCA) raises uncertainty related to the parameters that are subject to major changes over longer time spans. The main aim of the present study is to evaluate the influence of modifications in the electricity mix and the production efficiency in the chosen reference year on the embodied impacts (i.e., greenhouse gas (GHG) emissions) of building materials and components and the possible impact of this on future refurbishment measures. Methods: A new LCA methodological approach was developed and implemented that can have a significant impact on the way in which existing buildings are assessed at the end of their service lives. The electricity mixes of different reference years were collected and assessed, and the main datasets and sub-datasets were modified according to the predefined substitution criteria. The influence of the electricity-mix modification and production efficiency were illustrated on a selected existing reference building, built in 1970. The relative contribution of the electricity mix to the embodied impact of the production phase was calculated for four different electricity mixes, with this comprising the electricity mix from 1970, the current electricity mix and two possible future electricity-mix scenarios for 2050. The residual value of the building was also estimated. Results and discussion: In the case presented, the relative share of the electricity mix GHG emission towards the total value was as high as 20% for separate building components. If this electricity mix is replaced with an electricity mix having greater environmental emissions, the relative contribution of the electricity mix to the total emissions can be even higher. When, by contrast, the modified electricity mix is almost decarbonized, the relative contribution to the total emissions may well be reduced to a point where it becomes negligible. The modification of the electricity mix can also influence the residual value of a building. In the observed case, the differences due to different electricity mixes were in the range of 10%. Conclusions: It was found that those parameters that are subject to a major change during the reference service period of the building should be treated dynamically in order to obtain reliable results. Future research is foreseen to provide additional knowledge concerning the influence of dynamic parameters on both the use phase and the end-of-life phase of buildings, and these findings will also be important when planning future refurbishment measures. [ABSTRACT FROM AUTHOR]

Electrification of the transport sector is considered as a solution to reduce greenhouse gases (GHGs) emissions and achieve sustainable mobility. Specifically in the case of electrification of passenger vehicles, various industrial and policy initiatives have been introduced. In this article, we present and assess three approaches – pro-technology , pro-simplicity and mix (of the aforementioned approaches) – to achieve target emission reductions in the Norwegian road transport sector. We also assess the influence of including ‘Guarantee of Origin’ certification for the electricity production in accounting for typical consumption electricity mix in Norway. Results show that for the same reductions in tail-pipe GHG emissions, pro-technology, pro-simplicity, and the mix scenario offer 22%, 29% and 28% reduction in the life cycle GHG emissions respectively, compared to the reference scenario in year 2020. However, the pro-simplicity scenario requires 25% reduction in vehicle-km driven compared to the pro-technology scenario, which provides the same passenger car mobility as in the reference case. When the GHG intensity of the electricity mix used to power EVs is corrected to account for actual consumption mix in Norway, a 13% reduction in the net GHG benefit of pro-technology scenario is observed. [ABSTRACT FROM AUTHOR]

Battery electric vehicles (BEV) and Fuel cell electric vehicles (FCEV) are taking momentum as an alternative to conventional internal combustion engine vehicles (ICEV). Prospects of clean transportation and congruence with zero tailpipe emission are principal reasons for the adornment of these alternate technologies. This study aims to examine the collateral environmental impacts (GHG-100) that come alongside the production, use phase and end-life of ICEV, BEV and FCEV in the present context of Nepal. The current study uses a Cradle to Grave approach to compare the life cycle assessments (LCA) of Hyundai Tucson (2021), Hyundai Kona Electric 2021, and Hyundai Nexo Blue 2021 manufactured in South Korea (SK). Similarly, the LCA is performed under future scenarios of surplus electricity in Nepal and advancements in technologies. The results show that with the current import of 32% electricity from India, BEV and FCEV have 187- and 922-g total carbon dioxide equivalent (gCO 2 -eq) greenhouse gas (GHG) emission per kilometer respectively, which is 507 gCO 2 -eq/km for ICEV under the 200,000 km lifetime assumption of vehicles. The upstream emission for both the BEV and FCEV is poised to decrease by 88% with the surplus electricity scenario in Nepal, reducing 82% of the total emission of FCEV and 50% of BEV contributing to a cleaner local and global environment. Electricity sources significantly affect GHG emissions in both the production and use phases. Use of renewable electricity sources, and improvement in battery and fuel cell technologies reducing vehicle production supply chain impact with sharpened guidelines and policies regarding e-mobility, BEV and FCEV present themselves as promising alternative transportation technologies. [Display omitted] • Manufacturing emissions from electric vehicles is comparable to diesel vehicles. • Electric vehicles have significant global manufacturing supply chain emissions. • Low-carbon intensity electricity mix greatly reduces electric vehicle emissions. • With surplus hydroelectricity resources Nepal has promising electric vehicle potential. • Adaptation of electric vehicles requires sharpened guidelines and policies. [ABSTRACT FROM AUTHOR]

Abstract: Shallow geothermal systems such as open and closed geothermal heat pump (GHP) systems are considered to be an efficient and renewable energy technology for cooling and heating of buildings and other facilities. The numbers of installed ground source heat pump (GSHP) systems, for example, is continuously increasing worldwide. The objective of the current study is not only to discuss the net energy consumption and greenhouse gas (GHG) emissions or savings by GHP operation, but also to fully examine environmental burdens and benefits related to applications of such shallow geothermal systems by employing a state-of the-art life cycle assessment (LCA). The latter enables us to assess the entire energy flows and resources use for any product or service that is involved in the life cycle of such a technology. The applied life cycle impact assessment methodology (ReCiPe 2008) shows the relative contributions of resources depletion (34%), human health (43%) and ecosystem quality (23%) of such GSHP systems to the overall environmental damage. Climate change, as one impact category among 18 others, contributes 55.4% to the total environmental impacts. The life cycle impact assessment also demonstrates that the supplied electricity for the operation of the heat pump is the primary contributor to the environmental impact of GSHP systems, followed by the heat pump refrigerant, production of the heat pump, transport, heat carrier liquid, borehole and borehole heat exchanger (BHE). GHG emissions related to the use of such GSHP systems are carefully reviewed; an average of 63t CO2 equivalent emissions is calculated for a life cycle of 20 years using the Continental European electricity mix with 0.599kg CO2 eq/kWh. However, resulting CO2 eq savings for Europe, which are between −31% and 88% in comparison to conventional heating systems such as oil fired boilers and gas furnaces, largely depend on the primary resource of the supplied electricity for the heat pump, the climatic conditions and the inclusion of passive cooling capabilities. Factors such as degradation of coefficient of performance, as well as total leakage of the heat carrier fluid into the soil and aquifer are also carefully assessed, but show only minor environmental impacts. [Copyright &y& Elsevier]

• GHG emissions of different EV charging strategies in Europe in 2050 are analyzed. • A model coupling concept of linking LCA and PERSEUS-EU is applied. • Emissions from uncontrolled charging are higher than controlled charging strategies. • Vehicle-to-Grid (V2G) has lower emissions than unidirectional charging. • V2G is not the silver bullet and its success is sensitive to many influences. The growing market share of electric vehicles (EV) has increased the interest in charging strategies and their effects on the electricity system as well as their climatic soundness. However, the benefits of different charging strategies including Vehicle-to-Grid (V2G) on a large regional scale, e.g. in Europe, have not been analyzed sufficiently. This study examines the impact of different charging strategies on greenhouse gas (GHG) emissions from electricity generation and EV batteries in Europe in 2050. To consider indirect emissions and potentially additional battery degradation due to V2G, a model coupling concept is applied to link Life Cycle Assessment (LCA) with the electricity system model, PERSEUS-EU. Overall, EV could reduce the GHG emissions by 36% by simply replacing conventional cars. Controlled unidirectional charging and V2G add another 4 or 11 percentage points on the European level. However, for these gains an efficient implementation of V2G is required. [ABSTRACT FROM AUTHOR]

Electric vehicles, when coupled to electricity generation from renewable energy sources, can become a viable solution to decarbonize the transport sector. However, given the high variability of electricity mixes on a daily and seasonal basis, high-resolution profiles are needed for a precise analysis of the impacts of electric vehicles in terms of greenhouse gases emissions. This paper presents a comparison of different charging profiles evaluated on 10 European countries over four years, to highlight the effects of national electricity mixes and of the type of charging location on the specific emissions of EVs charging. This study, based on three archetypal charging profiles, provide a quantification of the potential influence of different charging strategies on the average emission factor of the electricity supplied to electric vehicles. The results show that the variability related to charging profiles is generally limited, with an average variation range of 6% for any given country and year, while in several countries the variability from one year to another is much larger, with an average range of 18% for any given country and charging profile. [ABSTRACT FROM AUTHOR]