Reprint of “The future of hydropower in Europe: Interconnecting climate,markets and policies”

Hydropower is very important for electricity supply security in the European inter-connexion as well as for the economy of regions (primarily peripheral) that possess water resources. Its future may however be jeopardized by several factors: climate change, the development of new renewable energy, the creation of super and micro-grids, and progress in power storage technology. Energy and climate policy, as well as electricity market design and dynamics play a pivotal role.This article carries out a comprehensive analysis of all these factors and discusses the future of hydropower. This discussion follows an overview of the present situation and of future drivers. The technical, environmental, economic and political aspects of the problem are analyzed with an interdisciplinary approach. The stakes as well as the uncertainties are highlighted.The conclusion is that hydropower has a promising future, particularly in light of emerging sustainable energy policy, but that the risks should not be overlooked. Academics will find a comprehensive interdisciplinary analysis of hydropower in this article, whereas public bodies, communities and hydropower companies can identify the strategic variables that should be taken into consideration in the decision making process. The end of water concessions or authorizations is also evoked.     

Abnormal energy metabolism and tau phosphorylation in the brains of middle-aged mice in response to atmospheric PM2.5 exposure

In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter (PM_2.5) can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM_2.5 inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM_2.5 ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM_2.5 inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.     

Energy and environmental attitudes in the green state of Denmark: Implications for energy democracy,low carbon transitions,and energy literacy

This article investigates how a mix of energy-users from Denmark perceives energy and environmental issues such as the affordability of electricity and gasoline, the seriousness of climate change, and preferences for different energy systems. Its primary source of data is a pilot survey and energy literacy test distributed in English and Danish to 328 respondents spread across the country. The survey results are used to test four propositions about energy prices, being “green,” public knowledge and competence about energy issues, and self-sufficiency and sustainable technology. The data supports the propositions that Danes identify with “being green” and prefer national and local policies that endorse sustainable technology and being self-sufficient. However, the data also challenges the propositions that Danes would prioritize low energy prices and affordability as key energy concerns and that they are knowledgeable about energy and environmental issues. In this way, a problematic gap may exist between what many academic articles (and previous surveys) report Danish attitudes to be and what this study suggests they are. Given Denmark's ambitious low-carbon goals, these findings have clear relevance to other communities and countries seeking to decarbonize their own energy sectors.     

The “second dividend” and the demographic structure

The demographic structure of a country influences economic activity. The “second dividend” modifies growth. Accordingly, in general equilibrium, the second dividend and the demographic structure are interrelated. This paper aims at assessing empirically the “second dividend” in a dynamic, empirical and intertemporal setting that allows for measuring its impact on growth, its intergenerational redistributive effects, and its interaction with the demographic structure. The paper uses a general equilibrium model with overlapping generations, an energy module and a public finance module that distinguishes between non-ageing-related public spending and a pension regime. Policy scenarios compare the consequences of different scenarios of recycling a carbon tax through lower proportional income taxes rather than higher public lump-sum expenditures. They are computed for two countries with different demographics (France and Germany). Results suggest that the magnitude of the “second dividend” is significantly related with the demographic structure. The more concentrated the demographic structure on cohorts with higher income and saving rate, the stronger the effect on capital supply of the second dividend. The second dividend weighs on the welfare of relatively aged working cohorts. It fosters the wellbeing of young working cohorts and of future generations. The more concentrated the demographic structure on aged working cohorts, the higher the intergenerational redistributive effects of the second dividend.     

Environmental policy and misallocation: The productivity effect of intensity standards

Firm-level idiosyncratic policy distortions misallocate resources between firms, lowering aggregate productivity. Many environmental policies create such distortions; in particular, output-based intensity standards (which limit firms energy use or emissions per unit of output) are easier for high-productivity firms to achieve. We investigate the productivity effect of intensity standards using a tractable general-equilibrium model featuring multiple sectors and firm-level heterogeneity. Qualitatively, we demonstrate that intensity standards are always inferior to uniform taxes, as they misallocate both dirty and clean inputs across firms and sectors, which lowers productivity. Quantitatively, we calibrate the model to US data and show that these productivity losses can be large.     

A Parametric Study of a Piston-Prop Aircraft Engine Using Exergy and Exergoeconomic Analysis Methods

In this study, exergetic and exergoeconomic analysis methods are applied to a four-cylinder, spark ignition (SI), naturally aspirated and air-cooled piston-prop aircraft engine in the cruise phase of flight operations. The duration of cruise is selected to be 1 h. Three parameters, altitude, rated power setting (PS), and air-to-fuel ratio (AF), are varied by the calculation of the max–min values of exergy analysis. Based on the results of energy analysis, the values for the maximum energy efficiency and fuel consumption flow rate are calculated to be 21.73% and 28.02 kg/h, respectively, at 1000-m altitude and 75% PS. The results of exergy analysis indicate that all exergetic values vary from 65% to 75% PS, while this increase is not seen in exergoeconomic analysis. While the maximum exergy input rate is obtained to be 405.60 kW, exergy efficiency has the minimum value with 14.43% and exergy destruction rate has the maximum value with 168.48 kW. These values are achieved at 3000-m altitude and 18 AFs. The maximum average exergy cost of the fuel is calculated to be 130.77 $/GJ at 1000-m altitude, 13 AF ratios, and 65% PS. At this point, while the minimum cost rate associated with the exergy destruction is obtained to be 40.29 $/h, the maximum exergoeconomic factor is found to be 19.98%.     

关于有机废物类生物质能历史定位及其能源价值评估指标探讨

中国是煤炭消耗的第一大国,同时又是有机废物生物质贮存量第一大国。本文叙述了全球生物质能的历史定位,生物质能的主要评价指标,生物质的能源转换技术和生物质能可供给量模型分析与预测实例,以及我国有机废物类生物质能源化利用途径,并探讨了有机废物的能源利用与废物污染防治相结合的生物质能源发展道路。     

低碳经济下农作物秸秆能源利用需求性分析

本文介绍了农作物秸秆能源利用的几个途径,从能源短缺、环境压力、秸秆过剩数量压力以及发展农村经济等方面分析了在低碳经济下秸秆能源利用的需求性和紧迫性,提出应该加强秸秆能源利用技术研究,大力推广秸秆能源利用。     

长期低强度曝气技术处理黑臭水体的可行性研究

为在保持曝气复氧技术优点的同时,通过控制曝气强度以节约曝气能耗,较大幅度地降低运行成本,拓展其应用范围,提出了1种长期低强度曝气处理黑臭水体的河道复氧技术。取用上海市徐汇区新港河水为实验用水,通过长期低强度曝气与连续曝气,间歇曝气的比较实验,结果表明,低强度曝气技术消除河道黑臭是完全可行的,同时还能有效去除水体污染负荷。实验中,氨氮去除率90%以上时,低强度曝气所消耗能源仅为连续曝气的10.52%和间歇曝气的25%,可节约大量的能源。     

Competitive regimes in forest-dwelling Hanuman langur females (Semnopithecus entellus)

Van Schaik’s socioecological model predicts interrelations among food distribution, competitive regimes, and female social relationships. To test the internal consistency of the model, feeding competition was examined in three differently sized groups of a forest-dwelling population of Hanuman langurs (Semnopithecus entellus). The nutritional condition of females was used as a direct indicator of feeding competition and related to the seasonal variation in resource distribution and abundance. Female dominance hierarchies were characterized by displacements. Dominance hierarchies were significantly linear and relatively stable, but less so with increasing group size. Physical condition correlated with dominance rank and high-ranking females were in the best condition, indicating within-group contest competition. The strength of this relationship became less pronounced with increasing group size. The females of the medium-sized group were in the best physical condition indicating between-group contest plus within-group scramble competition. Closer examination revealed variable costs and benefits of group foraging with a predominance of within-group scramble competition when food was more abundant. The results support some basic predictions of the model. Limiting food abundance was bound to ubiquitous within-group scramble competition. The use of clumped resources translated into differences in net energy gain based on dominance. In contrast to the predictions, group-size-related costs and benefits were related to food abundance instead of food distribution. As predicted, within-group contest competition was linked to a linear dominance hierarchy. The absence of nepotism and coalitions in Hanuman langurs may be attributed to dominance hierarchies that are unstable through time, probably minimizing fitness gain via kin support. Received: 25 May 1999 / Received in revised form: 18 February 2000 / Accepted: 25 February 2000