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Thermo-economically optimal design = optimal molecule + optimal process + optimal equipment.

This paper presents a stochastic bi-level approach for tariff design in the electricity market where the leader is represented by a retailer and the follower by a residential prosumager, i.e. a consumer equipped with an energy system consisting of photovoltaic panels and a battery storage device. Both players solve an optimization problem subject to uncertainty in market prices, weather-related variables and electricity demand. To account for the retailer’s attitude towards risk, the upper level problem includes a safety measure to maximize. The model allows to determine a dynamic pricing scheme with time-variant rates delivering the average profit that can be gained in a given percentage of unfavorable realizations of the uncertain parameters and the optimal load pattern that minimizes the expected prosumager's electricity bill. The stochastic bi-level problem is reformulated as a single level model and different approaches to deal with the lower level problem and the non linearity in the objective function are analyzed and empirically investigated. A large number of numerical experiments have been carried out on real test cases. The results have shown the efficacy of the proposed approach as a tool to define pricing schemes that reflect the retailer's risk attitude underlining the importance of explicitly dealing with uncertainty.

The opportunities and challenges of applying micronutrients (MiNs) in full-scale anaerobic digestion (AD) plants has been reviewed. The review discusses the underlying mechanisms and the role of different micronutrients (Fe, Ni, Co, Mo, Zn, Cu, Se) in the enhancement of AD performance, as well as their environmental and economic implications in full-scale AD systems. Bioavailability is a key factor affecting the effectiveness of micronutrients application on the biochemical aspects of AD. Accordingly, the technical aspects of AD with a direct impact on bioavailability have been identified and critically addressed. Mono-supplementation is not the most favorable strategy to increase micronutrient bioavailability due to limited solubility, formation of insoluble compounds, interaction with other compounds, and specific microbial requirements. Nonetheless, co-supplementation can increase the bioavailability due to the simultaneous synergetic effects of co-micronutrients supplementation on the biochemical aspects of AD. However, the inconsistency of reported lab-scale results and the lack of protocols or guidelines for analyzing the bioavailability of micronutrients limit results interpretation and full-scale application. The environmental and economic implications of these micronutrients are other critical factors that need further research. The economic results showed that the mono-supplementation can be economically favorable when a methane enhancement of 20% is achieved. Co-supplementation of micronutrients is the most economically feasible option since this strategy allows reducing the total dosage of micronutrients when compared with mono-supplementation. The authors are grateful for the scholarship from the TUM SEED Center of the Technical University of Munich, which is part of the DAAD (German Academic Exchange Service) program “exceed” supported by DAAD as well as the German Federal Ministry for Economic Cooperation and Development (BMZ) and in cooperation with the hosting Chair of Urban Water System Engineering of TUM. Sergi Astals is thankful to the Spanish Ministry of Science, Innovation and Universities for his Ramon y Cajal. Peer Reviewed

We try to understand the role of technological change and diffusion of energy efficient technologies in order to explain the trend of energy intensity developments in the German steel industry. We selected six key energy efficient technologies and collected data to derive their diffusion since their introduction in Germany. Since all technologies have been applied in Germany for more than 30 years we would expect complete diffusion. We found complete diffusion only for basic oxygen furnaces and continuous casting. Newer technologies (i.e. basic oxygen furnace gas recovery, top pressure recovery turbine, coke dry quenching and pulverized coal injection) diffused quicker in the initial phase but then diffusion slowed down. Key improvements in energy efficiency are due to electric arc furnaces (24%), basic oxygen furnaces (12%), and continuous casting (6%) between 1958 and 2012. The contribution of top pressure recovery turbines, pulverized coal injection and basic oxygen furnaces gas recovery accounts in total of about 3%. If the selected technologies were diffused completely, the future energy consumption could be reduced by 4.5% compared to 2012. Our findings suggest that our selection of six technologies is the key driver for energy intensity developments within the German steel industry between 1958 and 2012.

The interplay between excitatory pyramidal neurons and GABAergic interneurons is the basic building block of neocortical microcircuits and plays a critical role in carrying out higher cognitive functions. Cortical circuits are deeply and permanently disrupted by exposure to alcohol during brain development, the main non-genetic cause of intellectual disability. Here, I review experimental studies of fetal alcohol spectrum disorders, dealing with permanent cellular and molecular alterations of neocortical neurons and their connections.

Abstract While it is generally accepted that our fossil fuel-dominated energy systems must undergo a sustainable transition, researchers have often neglected the potential impacts of this on water and land systems. However, if unintended environmental impacts from this process are to be avoided, understanding its implications for land use and water demand is of crucial importance. Moreover, developed countries may induce environmental stress beyond their own borders, for instance through extensive imports of bioenergy. In this paper, Germany serves as an example of a developed country with ambitious energy transformation targets. Results show that in particular, the politically-driven aspiration for more organic farming in Germany results in a higher import quota of biomass, especially biofuels. These imports translate into land demand, which will exceed the area available in Germany for bioenergy by a factor of 3–6.5 by 2050. As this will likely bring about land stress in the respective exporting countries, this effect of the German energy transformation ought to be limited as much as possible. In contrast, domestic water demand for the German energy system is expected to decrease by over 80% through 2050 due to declining numbers of fossil-fuelled power plants. However, possible future irrigation needs for bioenergy may reduce or even counterbalance this decreasing effect. In addition, energy policy targets specific to the transport sector show a high sensitivity to biomass imports. In particular, the sector-specific target for greenhouse gas reductions will seemingly promote biomass imports, leading to the above-described challenges in the pursuit of sustainability.

AbstractThis study describes the relationships between climate change and the concept of a circular economy, outlining the need for synergies within a company's context. It reports on a bibliometric analysis of the relations between climate change and circular economy, and it provides evidence and assessments based on a sample of 11 large companies in the chemical industry. The results show that there is a concern in the academic literature to discuss circular economy efforts to combat climate change, reduce carbon emissions, strengthen the supply chain, assess the life cycle of products, their environmental impact, and waste management, and identify barriers to implementing the circular economy. In addition, there is a close association between the CE concept and tackling climate change in how organisations report their practices to the stakeholders, in considering concepts of recycling, reusing, adopting renewable energy, seeking resource efficiency, and rethinking strategies. The study concludes by providing some suggestions that may assist companies in intensifying their efforts to reduce their carbon footprint, combining them with more circular business models. Efforts from interested stakeholders must focus on defining CE in a more detailed manner, as well as its implementation at the different stages of production and consumption, especially in operations for which no uniform approach or common practice can be established. In this context, implications for positive social and environmental impacts by promoting a faster and more proactive climate transition in the chemical sector are presented. The novelty of this paper relies on the fact that it advances knowledge on matters related to the circular economy under a climate change context, identifying current trends and suggesting some measures which may optimise current business practices of the chemical sector.

Abstract The rapid uptake of renewable energy sources requires new forms of flexibility in electricity systems, including a more responsive demand-side. The social acceptability, scale and economic value of flexible demand remain subjects of conjecture. In this paper we inform this debate with a multi-methods approach using three instruments: surveys, observations and modelling. This multi-method approach brings out similarities and differences between Germany and Great Britain in relation to demand-side flexibility. Participants in both countries express a high willingness to participate in time variant tariffs, but their implementation may need to be context specific. In Germany national peak demand occurs at midday, when PV generation results in lower emission factors. Conversely, British peak demand is in the early evening when emission factors are at their highest. The differences in responses allow us to explore important technical and cultural differences affecting the need for flexibility. Germany gains most from flexibility during the daytime in summer, while flexibility in Great Britain contributes most during winter evenings. We observe high degrees of acceptability of time-variant electricity tariffs (55%) and willingness to shift demand is high, resulting in peak demand reductions of up to 14.5%. However, the resulting cost and carbon savings of these efforts is less than 2% in both countries. We conclude that short term carbon or cost savings may be less powerful motivators for load shifting measures than long term system decarbonisation.