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A Life Cycle Assessment (LCA) with focus on carbon footprint, followed by Life Cycle Costing (LCC) of municipal solid waste (MSW) management were conducted in a residential area of a medium-sized European city of 80,000 inhabitants. The initial results showed high environmental impacts and lack of economic sustainability, due to the high amounts of waste landfilled, the low extent of separate collection, low performance of mechanical-biological treatment as well as absence from alternatives to landfilling of non-recyclable materials. Taking this result as a baseline scenario, three improvement.s were tested with the aim of turning the carbon footprint of the local MSW management system into a neutral value: (i) increased separate collection of recyclables, (ii) enhanced biogas production and (iii) refuse-derived fuel (RDF) production. Successively adding the improvements, three alternative improved scenarios were defined, until reaching a negative carbon footprint, meaning that an optimised system would avoid GHG emissions. The proposed changes were sufficient to achieve carbon neutrality, as well as reduce overall environmental impacts, but were not enough for achieving economic sustainability due to the great influence of collection costs, especially for separate collection. It was concluded that by using an adequate combination of several treatment options and increasing the separate collection of recyclable materials it is possible to turn MSW management into a carbon neutral activity as well as improve its economic balance.

A methodology is proposed based on thermogravimetric analysis, deconvolution of the DTG signal and empirical correlations for characterizing biomass fuels for boilers and combustors. This methodology allows determining accurately and in a short time the main parameters required for industrial operation, as are the higher heating value (HHV), the contents of moisture, volatile matter, fixed carbon, ashes, carbon, hydrogen and oxygen, and the kinetic parameters of the thermal decomposition of the biomass. At the present time, these parameters are obtained by using specific equipment that are much more sophisticated and expensive than the methodology proposed. Twelve types of vegetable lignocellulosic biomasses have been used in the study, i.e., wastes from wood industry, food industry and agriculture. The comparison of the results obtained, based on the methodology developed in this paper, with those published in the literature evidence the validity of the methodology for a wide range of materials.

The aim of this work is to show the effects in a PV cell of the combined profiles of non-uniform temperature and radiation. Particular attention is paid to the modelling of cell operation at open circuit voltage with those profiles, as long as they serve as a general model in different circumstances: combined direct Gaussian temperature and radiation profiles, with several temperature amplitudes and movement of these profiles across the cell; analysis under Gaussian concentrated illumination and inverse Gaussian temperature profile simulating a general cell cooling device. In addition, we will study the cell behaviour under truncated radiation and temperature profiles. Irregular radiation and temperature distributions will also be studied.

Abstract The market for insulation material is playing a crucial role in Europe's energy transformation, due to its influence on energy consumption in buildings. The introduction of renewable materials for thermal insulation is recent, and little is known so far about its environmental implications. This study analyses the environmental performance of a cork insulation board, made of agglomerated cork from forestry cork wastes, by means of cradle-to-gate Life Cycle Assessment methodology. The results indicate that the use of natural insulation materials does not necessarily imply a reduction of environmental impacts due to manufacturing processes with a low technological development. In this case, the most influential stage is the manufacturing stage, in which the board agglomeration and the cork trituration have the highest impacts. The most influential inputs are both the transport used during the life cycle and the large quantities of electricity and diesel in the manufacturing stage. Some strategies have been identified to reduce the environmental impact, such as promote the acquisition of local raw cork to reduce transportation from the manufacturer, improve the efficiency and productivity of manufacturing processes and improve the product design to help increase its market share. Moreover, the inclusion of biogenic carbon contained in forest-based building materials affects the Global Warming Potential results considerably. However, it is very important to consider how this biogenic carbon is calculated and how the product is managed after its lifetime.

AbstractClimate change globally affects soil microbial community assembly across ecosystems. However, little is known about the impact of warming on the structure of soil microbial communities or underlying mechanisms that shape microbial community composition in subtropical forest ecosystems. To address this gap, we utilized natural variation in temperature via an altitudinal gradient to simulate ecosystem warming. After 6 years, microbial co‐occurrence network complexity increased with warming, and changes in their taxonomic composition were asynchronous, likely due to contrasting community assembly processes. We found that while stochastic processes were drivers of bacterial community composition, warming led to a shift from stochastic to deterministic drivers in dry season. Structural equation modelling highlighted that soil temperature and water content positively influenced soil microbial communities during dry season and negatively during wet season. These results facilitate our understanding of the response of soil microbial communities to climate warming and may improve predictions of ecosystem function of soil microbes in subtropical forests.

Research, Technological Development and Innovation Program Oriented to the Society Challenges of the Spanish Ministry of Economy and Competitiveness [MCIN/AEI/10.13039/501100011033, MCI-20-PID2019-111051RB-I00]; European Union through ERFD Structural Funds (FEDER) through H2020 Research and Innovation programme [864459 (UE-19-TALENT-864459)]

AbstractThis paper suggests the integration of fast acting energy storage systems in existing pumped‐storage power plants as a practical solution to enhance the system's frequency control. The term “fast acting energy storage” is used in the paper to refer to, in the authors' opinion, the most suitable energy storage technologies for the purpose of frequency control, that is, flywheels and supercapacitors. The paper describes the few research works that have so far dealt with the coordination of flywheels or supercapacitors and pumped‐storage or hydropower, and compare the proposed solution with the upgrade of existing pumped‐storage power plants to allow variable speed operation. To finish, the paper describes other side benefits of the proposed solution, discusses the most important barrier for its realization and summarizes a few regulatory changes that have been recently implemented in a few electric power systems which provide some hope for the proposed solution to become a reality.This article is categorized under: Energy Infrastructure > Systems and Infrastructure

The general methodology for estimating energy consumption in buildings, in accordance with the EN ISO 13790, needs the use of constants that are valid for each set of climatic conditions. Furthermore, there are variables other than building structure and weather conditions that have an influence. In this sense, recent research works showed the real effect of permeable coverings on indoor environmental conditions, by controlling indoor moisture. The effect of the associated heat and mass transfer on heating or cooling energy consumption is evident during the initial hours of building occupation. In the present paper, the general methodology of building heat demand calculation is modified to consider different levels of permeability of internal coverings, in order to obtain a more accurate model. Results showed that permeable coverings are related with a higher building utilisation factor, and that the value of this factor is higher in summer than in winter season. Consequently, despite the fact that the sensibility of energy consumption to internal coverings may be lower than to building envelope, new constants are proposed to express a relationship between building permeability and energy consumption, in order to apply the certification equation.