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The European Union is targeting climate neutrality by 2050, with a focus on enhancing energy efficiency, expanding renewable energy sources, and reducing emissions. Within Italy's electricity mix, bioenergy sources, namely biogas, solid biomass, and bioliquids, play a crucial territorial role. A comparative analysis was conducted through Life Cycle Assessment (LCA), utilizing national data from the ARCADIA project, to assess the environmental sustainability of the investigated bioenergy chains and identify the most convenient ones. The study revealed that, among the bioenergy sources, solid biomass emerges as the most environmentally friendly option since it does not rely on dedicated crops. Conversely, biogas shows the highest environmental impact, demonstrating less favorable performance across nine out of the sixteen evaluated impact categories. The LCA underscores that the cultivation of dedicated energy crops significantly contributes to environmental burdens associated with electricity generation, affecting both biogas and bioliquids performance. The cultivation process needs water and chemical fertilizers, leading to adverse environmental effects. These findings highlight the importance of prioritizing residual biomass for energy generation over dedicated crops. Utilizing forestry and agro-industrial residues, municipal solid waste, and used cooking oils presents numerous advantages, including environmental preservation, resource conservation and recovery, as well as waste reduction. [ABSTRACT FROM AUTHOR]

Nuclear power can replace fossil fuels and will have a decisive impact on the change in the approach to conventional energy. However, nuclear (or radioactive) wastes are produced by the operation of the nuclear reactors should be safely and properly disposed of. This paper assesses the uranium resources and the global state of nuclear power plants and determines the energy mixes in different countries using the most nuclear energy. Furthermore, this paper analysed the nuclear waste management and disposal and the depletion of abiotic resources, and the primary energy sources of a basic production process using electricity mix and nuclear electricity for a basic production (PET bottle manufacturing) process. The life cycle assessment was completed by applying the GaBi 8.0 (version 10.6) software and the CML method. In this study, we limit our discussion to high-level nuclear waste (HLW) and spent nuclear fuel (SNF) waste. We do not consider waste generated from uranium mining and milling, which is usually disposed of in near-surface impoundments close to the mine or the mill. The investigation of waste management methods is limited to European countries. This research work is relevant because determining abiotic resources is important in a life cycle assessment and current literature available on LCA analysis for nuclear powers remains under-developed. These results can guide and compare manufacturing processes involving a nuclear electricity and electricity grid mix input. The results of this research can be used to develop production processes using nuclear energy with lower abiotic depletion impacts. This research work facilitates the industry in making predictions for a production-scale plant using an LCA of production processes with nuclear energy consumption. [ABSTRACT FROM AUTHOR]

Public support is an important factor in failure or success of the government decisions with respect to the electricity generation mix, which highlights the necessity of developing an electricity mix that reflects social preferences and acceptance. This study explores heterogeneity in social preferences for power sources and develops an electricity mix from a demand-side perspective. The study utilizes the choice-based conjoint survey and latent class model, and bases its empirical analysis on South Korea's electric power sector. Results demonstrate that preferences for power sources in Korean society consist of two classes: one that is sensitive to the environment and one that is sensitive to risk. An electricity mix for Korea that reflects social preferences is 16.5-19.8% coal-fired, 13.3-24.9% liquefied natural gas (LNG), 9.0-11.2% oil, 22.3-32.9% nuclear, and 18.5-38.9% renewables, depending on the scenario. The study confirms that renewables are the power source with the least potential to cause social conflict, compared to nuclear and coal-fired sources. Moreover, increasing the proportion of renewables (currently only 3.9%) while decreasing the proportion of coal-fired power sources (currently 39.9%) to less than half its current level will result in an electricity mix that is accordance with social preferences in the long run. [ABSTRACT FROM AUTHOR]

In August 2019, a new bus fleet of 36 electric and 58 hybrid buses were implemented in Trondheim, Norway. This paper examines the carbon footprint of electrified city buses, by addressing the achieved and potential reduction for the new bus fleet. Important aspects such as geographical location of production, charging electricity mix, and impact from production and operation on lifetime emissions, are also examined. A meta-analysis on life cycle assessment studies was undertaken to investigate greenhouse gas emissions and energy demand in different parts of bus production. This is followed by the production of a bus model using the findings and comparing electrified buses with diesel and HVO buses. The models were then used in a case study of the bus fleet in Trondheim, to understand the specific parameters affecting the carbon footprint. The results show that the overall carbon footprint has been considerably reduced (37%) by implementing biofuel and electrified buses, and that a further reduction of 52% can be achieved through full electrification. The operation emissions for the fleet were found to be 49 g CO2-eq/person-km, which is lower than the average city bus and passenger car in Norway. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the sensitivity of the optimal mixes to cost and variability associated with solar technologies and examine the role of Thermal Energy Storage (TES) combined to Concentrated Solar Power (CSP) together with time-space complementarity in reducing the adequacy risk—imposed by variable Renewable Energies (RE)—on the Moroccan electricity system. To do that, we model the optimal recommissioning of RE mixes including Photovoltaic (PV), wind energy and CSP without or with increasing levels of TES. Our objective is to maximize the RE production at a given cost, but also to limit the variance of the RE production stemming from meteorological fluctuations. This mean-variance analysis is a bi-objective optimization problem that is implemented in the E4CLIM modeling platform—which allows us to use climate data to simulate hourly Capacity Factors (CFs) and demand profiles adjusted to observations. We adapt this software to Morocco and its four electrical zones for the year 2018, add new CSP and TES simulation modules, perform some load reduction diagnostics, and account for the different rental costs of the three RE technologies by adding a maximum-cost constraint. We find that the risk decreases with the addition of TES to CSP, the more so as storage is increased keeping the mean capacity factor fixed. On the other hand, due to the higher cost of CSP compared to PV and wind, the maximum-cost constraint prevents the increase of the RE penetration without reducing the share of CSP compared to PV and wind and letting the risk increase in return. Thus, if small level of risk and higher penetrations are targeted, investment must be increased to install more CSP with TES. We also show that regional diversification is key to reduce the risk and that technological diversification is relevant when installing both PV and CSP without storage, but less so as the surplus of energy available for TES is increased and the CSP profiles flatten. Finally, we find that, thanks to TES, CSP is more suited than PV and wind to meet peak loads. This can be measured by the capacity credit, but not by the variance-based risk, suggesting that the latter is only a crude representation of the adequacy risk. [ABSTRACT FROM AUTHOR]

Energy transitions around the world will change the spatial fingerprint of the electricity sector, but there is a lack of studies on citizen preferences for siting the future mix of electricity technologies. Using the case of Switzerland in 2035, we present a serious board game to form and elicit citizen preferences for spatial siting of a full mix of electricity technologies and we test this game with 44 participants in the city of Zurich. The game proves to help elicit valid preferences of the participants and lead to measurable learning effects about this complex, multi-dimensional topic. The results show that these 44 participants prefer a diverse mix of renewable technologies for Switzerland in 2035. In terms of siting, these participants consistently choose the efficiency strategy, where new plants are concentrated in the areas where they produce most electricity at least cost, in contrast to the strategy of regional equity, where all Swiss regions would equally build new generation and share the benefits and burdens of the energy transition. [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]

For a successful transition to low-carbon electricity supply, public support is essential. Citizen preferences are best understood in the process of informed citizen panels, where citizens are informed about the pros and cons of various electricity technologies and spend time reflecting on the trade-offs. We investigated how information about electricity technologies and their sustainability impacts can change citizens' preferences and affect for the complete Swiss electricity mix 2035. The citizens received information as factsheets and, during workshops, discussed in groups and built their preferred electricity mix using an interactive tool. The informed citizen panel (N = 33) in the Swiss city of Geneva showed high support for domestic renewable technologies and end-use efficiency, as well as low support for net electricity import, natural gas, and nuclear power. Preferences and affect for unfamiliar technologies changed after receiving information and remained stable even in the longer term four weeks after. Preferences and affect for already familiar technologies, like hydropower, barely changed. The same procedure in the two Swiss cities of Geneva and Zurich (N = 46) enabled the identification of robust support for renewable technologies and efficiency with only minor context-specific differences. [ABSTRACT FROM AUTHOR]

In Europe, ethanol is blended with gasoline fuel in 5 or 10% volume (E5 or E10). In USA the blend is 15% in volume (E15) and there are also pumps that provide E85. In Brazil, the conventional gasoline is E27 and there are pumps that offer E100, due to the growing market of flex fuel vehicles. Bioethanol production is usually by means of biological conversion of several biomass feedstocks (first generation sugar cane in Brazil, corn in the USA, sugar beet in Europe, or second-generation bagasse of sugarcane or lignocellulosic materials from crop wastes). The environmental sustainability of the bioethanol is usually measured by the global warming potential metric (GWP in CO2eq), 100 years time horizon. Reviewed values could range from 0.31 to 5.55 gCO2eq/LETOH. A biomass-to-ethanol industrial scenario was used to evaluate the impact of methodological choices on CO2eq: conventional versus dynamic Life Cycle Assessment; different impact assessment methods (TRACI, IPCC, ILCD, IMPACT, EDIP, and CML); electricity mix of the geographical region/country for different factory locations; differences in CO2eq factor for CH4 and N2O due to updates in Intergovernmental Panel on Climate Change (IPCC) reports (5 reports so far), different factory operational lifetimes and future improved productivities. Results showed that the electricity mix (factory location) and land use are the factors that have the greatest effect (up to 800% deviation). The use of the CO2 equivalency factors stated in different IPCC reports has the least influence (less than 3%). The consideration of the biogenic emissions (uptake at agricultural stage and release at the fermentation stage) and different allocation methods is also influential, and each can make values vary by 250%. [ABSTRACT FROM AUTHOR]