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Artículos en revistas Energy transportation costs typically make up a quarter of consumers? electricity bills, and most of this amount (90% in the United Kingdom, 75% in Brazil and Spain, and 60% in India, for example) is due to energy transportation through the distribution network. This cost could escalate over the next few decades as distributed energy resources are expected to grow substantially in response to the financial incentives many governments have created for renewable and efficient generation to meet their CO2 reduction targets. info:eu-repo/semantics/publishedVersion

This study proposed an efficient way of direct sewage pre-concentration by a combined coagulation microfiltration (CCM) system and an optimal operational strategy of aeration. Compared to two typical technologies for sewage pre-concentration, i.e. direct sewage microfiltration (DSM) and continuous aerated sewage microfiltration (ASM), the CCM system under optimal aeration strategy showed higher concentration efficiency and slower permeability decline (i.e. better control of membrane fouling), and easier collection of retained organic matter (OM). A lab-scale CCM reactor was running continuously for 295 h, and a concentrate of about 16,000 mg COD/L was produced at an average net flux of 13.3 L/(m2 h) and an influent OM recovery of nearly 70%, which was higher than the concentrate produced by a high-loaded membrane bioreactor (MBR) with one day solids retention time. The use of chemical coagulant was found to have little impact on the following anaerobic digestion (AD) process, for anaerobic biodegradability of the concentrate is 56.5% (close to the typical value for blackwater). The integration of the CCM and AD processes could achieve a net energy production of 0.0098 kW h/m3 after deduction of 0.0919 kW h/m3 required for the operation of the CCM system, thus showing promise as an effective OM concentration method for energy recovery from sewage.

In order to achieve the Paris Agreement goals of keeping the temperature rise well below 2 °C or even 1.5 °C, all countries would need to make fair and ambitious contributions to reducing emissions. A vast majority of countries have adopted reduction targets by 2030 in their Nationally Determined Contributions (NDCs). There are many alternative ways to analyze the fairness of national mitigation contributions. This article uses a model framework based on six equity principles of effort-sharing, to allocate countries’ reduction targets under global emissions scenarios consistent with meeting the Paris climate goals. It further compares these allocations with the NDCs. The analysis shows that most countries need to adopt more ambitious reduction targets by 2030 to meet 2 °C, and even more for 1.5 °C. In the context of 2 °C, the NDCs of the United States of America and the European Union lack ambition with respect to the approaches that emphasize responsibility; China's NDC projection falls short of satisfying any approach in 2030. In the context of 1.5 °C, only India, by implementing its most ambitious efforts by 2030, could be in line with most equity principles. For most countries, the NDCs would use most of their allowed emissions space for the entire 21 st century by 2030, posing a major challenge to transform to a pathway consistent with their fair contributions in the long-term.

In recent years, ceria-based composites (CBCs) have been developed as electrolytes for low-temperature solid oxide fuel cells. These materials exhibit extremely high ionic conductivities at 400–600°C. It has also been found that both oxide ion and proton can be conducted in the CBC electrolytes, which makes such co-ionic conducting fuel cell distinct from any other types of fuel cells. In this study, a model involving three charge carriers (oxide ion, proton, and electron) is developed to describe the fuel cell with CBC electrolytes. Various operating characteristics of the fuel cell with CBC electrolytes are investigated, compared to those of the fuel cell with doped ceria electrolytes. The results indicate that the CBC electrolyte behaves as a pure ionic conductor, the cell is more efficient, and a higher output is expected at low temperatures under the same pressure operation than that of the cell with doped ceria electrolytes.