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In this paper, a viability study is conducted for a bioremediation intervention in a cultivated area contaminated by a pipeline oil spill. In this context, green technologies such as bioremediation and phytoremediation could represent an optimal solution for reducing pollution without deteriorating soil quality. The phytoremediation test was conducted at the microcosm scale using three plant species (Zea mays, Lupinus albus and Medicago sativa) and at the mesocosm scale (Zea mays), also evaluating the application of plant growth-promoting bacteria (PGPB). The results showed that the selected plants, being able to grow satisfactorily, are able to lessen the presence of hydrocarbons in the soil. An increase of 15–18% in the degradation of the C > 12 fractions in vegetated soils was observed, confirming the effect of plants on the biodegradation of hydrocarbons in the soil. Moreover, a further improvement was recorded after adding PGPB, resulting in fresh biomass production being up to 50% higher than the controls and the degradation of the C > 12 fraction increasing by up to an additional 10%. Particular attention was also paid to pyrene, considered an indicator of PAH contamination. At the end of the experimentation in vegetated soils, pyrene removal reached values above 50%. By favoring plant growth, the addition of PGPB resulted in a further up to 20% reduction in the content of the contaminant in the soil. The primary role of the plants in soil contaminated by petroleum derivatives was to accelerate the degradation of contaminants through the stimulation of microbial activity. Therefore, the cooperation between plants and microorganisms can be concretely used as a nature-based solution in a sustainable and economical way. [ABSTRACT FROM AUTHOR]

Featured Application: The Intergovernmental Panel on Climate Change (IPCC)'s Sixth Assessment Report (AR6) recognizes the physico-chemical process known as carbonation. The present paper utilizes a way of calculating carbon dioxide uptake quickly and easily following the simplified methodology known as Tier 1 applied to the largest cement consumer in South America. The worldwide cement industry plays an important role in addressing the climate change challenge. Brazil's cement industry currently has 91 cement plants with an installed production capacity of 94 million tons per year and has started to calculate the net CO2 emissions to achieve a carbon-neutral cement sector by 2050. Accordingly, the carbon dioxide uptake due to mortar and concrete carbonation is subtracted from the carbon dioxide emitted by the chemical reaction for the calcination of lime, i.e., the calcination process performed during clinker production. Now-adays, the Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas (GHG) Inventories to report the GHG emissions do not include any calculation procedure to consider the mortar and concrete carbonation. However, the Intergovernmental Panel on Climate Change (IPCC)'s Sixth Assessment Report (AR6) recognizes the physico-chemical process known as carbonation. Brazilian net carbon dioxide emissions of cements produced from 1990 to 2019 are estimated considering the carbon dioxide uptake during the service-life and end-of-life and secondary usage stages (Tier 1). This is a fundamental scientific and technological novelty that changes the current approach to estimate the carbon dioxide emissions due to the Portland cement clinker production. Even considering the relative novelty of this approach, it should be promoted in the future and included in the national inventory report (NIR). The carbon dioxide uptake by mortar and concrete carbonation for 30 years is about 140 million tons. Within this thirty-year period about 483 million tons have been released due to the calcination process. [ABSTRACT FROM AUTHOR]

Semiconductor and display industries in the Republic of Korea make up the global electronics market with some of the greatest potential for growth due to accelerated digital transformation. Greenhouse gases (GHGs) present in the Earth's atmosphere could trap heat and contribute to the greenhouse effect, leading to global warming and climate change, and it is important to note that while GHGs are naturally present in the atmosphere and play a crucial role in regulating the Earth's temperature, human activities have significantly increased their concentration, leading to accelerated global warming and climate change. Volatile fluorinated compounds (FCs), including perfluorocompounds (PFCs), hydrofluorocompounds (HFCs), NF3, and SF6, are potent long-standing greenhouse gases that are used and emitted by electronics during the manufacturing and display stages of semiconductors. In accordance with global climate change, GHG reduction has developed as a demand of the times, and the electronics industry has also made efforts to reduce GHG emissions in response. Until now, process emissions from the use of fluorinated greenhouse gases (F-GHGs) in various industries have been calculated according to the '06 IPCC G/L, and emission factors of '06 IPCC G/L have also been applied. However, the reduction and emission factors proposed in the IPCC G/L are values that do not reflect the latest and advanced reduction technologies in South Korean electronics, and national GHG emissions are overestimated. In this paper, by preparing accurate measurement methods for destruction removal efficiency (DRE), the use rate of gas (Ui), and b-product emission factors (Bby-product, i), which are characteristic parameters for estimating GHG Tier 3a emissions, we aim to increase the accuracy of GHG emissions by advancing emission factors that are unique to the semiconductor and display industries within the Republic of Korea. [ABSTRACT FROM AUTHOR]

In recent years, many cities around the world have pledged to upgrade their building stocks to carbon-neutral. However, the literature does not yet provide a shared definition of carbon-neutral building (CNB), and the assessment objectives and methodological approaches are vague and fragmented. Starting from the available standards and scientific literature on life cycle assessment (LCA), this paper advances an operational definition for CNB on the basis of an explicit calculation approach. It then applies the definition to an urban case study, comparing it against a state-of-the-art nearly Zero Energy Building (nZEB) scenario, with the intent of highlighting the major practical limitations connected to the application of a methodologically sound carbon neutrality calculation. The case study shows that carbon neutral objectives can hardly be achieved by single urban buildings because of the lack of spaces that can provide onsite carbon offsetting actions. Carbon neutrality may be better approached at the city, regional, or national scales, where overarching policies may be defined. [ABSTRACT FROM AUTHOR]

A novel multifactor algorithm is developed with the aim of estimating GHG emissions in the EU countries and forecasting different future scenarios. This is created starting from (1) GDP, (2) population and (3) renewable energy share (RES). The determination coefficient (R2) of the multiple regression adopted reaches a value of 0.96; thus, only 4% of the GHG variation cannot be explained by the combination of the three variables. Germany is removed from the model after analysing the statistical outliers, as it presents an unusual behaviour within the European context. Also, France, Italy and Ireland are removed in the forecast analysis since they are characterised by corrected weighting values above the threshold value of the algorithm (0.156). The results show that GHG emissions decrease 14% in a low-growth-rate scenario, increase 24% in an average-growth scenario and increase 104% in a high-growth-rate scenario. Countries that improve the most are the ones that are currently underdeveloped in RES and are expected to decrease their population in the future (Croatia, Latvia, Cyprus and Greece). Other countries currently well positioned but with expected population growth (Sweden, Luxemburg and Denmark) or with expected intense GDP growth (Estonia and Malta) may lack decarbonisation levers. Therefore, policy makers should introduce additional subsidy schemes and tax exemptions in both developed and less developed countries to meet EU decarbonisation targets. [ABSTRACT FROM AUTHOR]

The attainment of carbon neutrality requires a research agenda that addresses the technical and economic challenges that will be encountered as we progress toward 100% renewable electricity generation. Increasing proportions of variable renewable energy (VRE) sources (such as wind turbines and photovoltaic systems) render the supply-and-demand balance of VRE-dominated power grids difficult. The operational characteristics and effects of VRE inverters also require attention. Here, we examine the implications of the paradigm shift to carbon neutrality and summarize the associated research challenges in terms of system planning, operation, and stability, and the need for energy storage integration, demand-side participation, distributed control and estimation, and energy sector coupling. We also highlight the existing literature gaps, and our recent studies that can fill in the gaps, thereby facilitating the improvement of grid operation and estimation. The numerical results of comparative case studies are also provided on the operational stability and economics of power grids with a high level of VRE sources, assisting stakeholders in establishing specific roadmaps and making relevant decisions. [ABSTRACT FROM AUTHOR]