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This paper shows the results obtained from the study on the variables that have the greatest influence on the decision to replace three-phase induction motors, without a defined efficiency class and installed in industrial applications, with IE3 efficiency class induction motors. The work has been carried out on motors with a nominal power of 1.5 kW due to the availability of laboratory tests that have allowed us to accurately quantify the selected study variables. According to IEC 60034-30, between 0.75 kW and 4 kW is the greatest potential for energy savings in electric motors installed within the industrial sector. The tests carried out have made it possible to assess different operating conditions of the motor: direct power supply from the grid, electronic power supply using scalar control, and electronic power supply using direct torque control. The study has focused on three aspects: energy evaluation, assessing the savings potential; economic evaluation, based on indicators such as Payback Period and Net Present Value; environmental assessment, quantifying the impact indicators proposed by the Methodology for Ecodesign of Energy-related Products (MEErP). A sensitivity analysis has been carried out to quantify, through ratios, different operating points from those directly analyzed in the article.

Chinese solar greenhouses (CSGs) are characterized by unique walls to reduce the transmission of heat and promote the energy conservation in winter production, which promotes cultivation in the northeast region of China in winter. Effective selection of insulation material is important for the CSG based on the energy consumption and economic analysis. However, choosing the thickness of the insulation material in walls often discussed with the structure of CSG. There is a lack of research combing the optimal insulation thickness for improving the energy conservation. The aim of this study was to find the optimum insulation thickness during the energy conservation based on the structure of walls, the energy consumption in local climatic conditions, the cost of insulation material, and economic payback period over a lifetime. By the economic analysis of insulation thickness, thermal resistance, lifetime energy saving, and payback period, three kinds of typical walls (clay brick (CB), hollow concrete block (HCB) and fly ash block (FAB)) combed with four insulation materials including the expanded polystyrene, the foamed PVC, the perlite, and the rock wool were calculated. The optimum insulation thickness can be found when energy savings reached the maximum. In the northeast region, the association of FAB with rock wool as the insulation layer was the most economic composite wall structure. The optimum insulation thickness was 0.05 m, with the cost only 5 USD/m2. The thermal resistance of composite wall had a significant effect on the payback period. When thermal resistance increased from 0.2 to 1.2 m2K/W, the payback period varied from 0.4 to 4.3 years. What is more, the energy consumption in local climatic conditions had a more significant effect on payback period. It can be assumed that insulation materials are more favored in cold climatic regions where heating degree-days over 1600 °C days for payback periods is less than 2 years. These results have strong practical and economical significance in saving energy and improving the environment of CSG.

The use of photovoltaic solar technology is increasingly widespread and consolidated worldwide, gaining significant interest in Brazil. Thanks to records of gradual photovoltaic system price decreases and the construction of legal frameworks favorable to their diffusion, urban and rural residential consumers, service companies, industries, and the government are progressively adhering to the use of this technology. In this context, it is important that institutions and companies with multiheadquarters discern whether it is more advantageous, from both a technical and economic point of view, to disperse photovoltaic systems throughout all of their headquarters or to centralize them in the offices presenting the best energy efficiency. The present study aims at answering this question. To this end, indicators recorded in the Institute of Education Science and Technology (IFRN)-Solar Project implemented by the Rio Grande do Norte Federal Institute of Education, Science and Technology, in Brazil, where 2 MWp of photovoltaic solar energy are installed in 19 of its 22 headquarters, were evaluated. The PVWatts Software, energy measurements at the different plant installation locations and technical performance parameters recurrent in the literature, as well as the Discounted Payback Method were used herein. The results indicate that system centralization in the best-evaluated sites (7 campi) will, in 25 years, provide a 9.07% energy supply gain, a 112.96% financial gain, and a payback reduction of 8.9 years when compared to the alternative comprising generation unit dispersion throughout the 19 campi.

Can payback, punitive action fueled by the desire to hurt an offending aggressor, ever be justified? In Anger and Forgiveness, Martha Nussbaum emphatically answers “no”, arguing that payback and the anger on which it is based, even following severe loss, distracts one from pursuing the betterment and loving nature one should be striving to cultivate instead. Timothy Jackson admires Nussbaum’s appreciation for such a beautiful spiritual ideal but criticizes her for denying credit to the potential feeler of anger for overcoming the temptation to engage in payback, the initial presence of which is critical for a graceful and triumphant self-transformation. Diana Cates, qualifying Jackson, maintains that we should not assume in payback scenarios that it is suffering that is aimed at, even if the experienced pain of an offender is foreseeable. Granting the worthwhile high road Nussbaum and her respondents seek to travel, one may still ask: is there also a positive case to be made for desiring payback in the extreme case of responding to an egregious offense, i.e., an offense that is violent, paralyzing, and life-altering? Payback will not bring a lost loved one back from the dead, but can it bring oneself back from the dead? This essay explores the merits of this possibility, honing in on the therapeutic aspect of the desire—and occasionally the acting out of the desire—for a victim to pay her aggressor back in kind. Drawing on the work of the Christian realist Reinhold Niebuhr, the Judaic thinker and Holocaust survivor Primo Levi, and the Christian ethicist and feminist Giles Milhaven, I argue that while no moral principle ever ought to be adopted out of retributive action—such action is by definition bereft of virtue—we should nevertheless not dismiss too quickly the notion of there being any moral value in desiring payback, for desiring payback might be an egregiously offended victim’s only alternative to the paralysis induced by malice. On this exceptional basis, payback strictly limited to its therapeutic scope may become, for the sake of preserving self-worth, not only tolerable, but a victim’s most preferable alternative.

This essay takes a fresh approach to a traditional Western philosophical account of anger, according to which anger is best defined as a desire for payback, namely, a desire to make an offender pay a price, in the currency of unwanted pain, for the pain he caused someone else. The essay focuses more specifically on the work of Thomas Aquinas, whose account of anger is often thought to center on a desire for ‘just vengeance.’ It analyzes and extends aspects of Aquinas’s account that have previously been treated too narrowly. It distinguishes three forms of anger, each of which has important features in common, which justify characterizing it as anger. Only one of these forms involves a desire to make an offender suffer for what he did. Even as this essay argues for articulating different forms of anger, it emphasizes the fluidity of anger’s forms, features, and relationships to other emotions. It briefly engages philosophical, psychological, and neuroscientific perspectives while working principally in the domain of religious ethics and moral psychology.

Martha Nussbaum’s Anger and Forgiveness makes explicit claims about the moral valence and irrationality of the desire for payback. This article explores the roots of that desire through an analysis of research on inequity aversion in primates, and the sociocultural developmental context for expressions of anger. It explores the content of different expressions of anger and their relationship to rationality by engaging in the work of Thomas Aquinas. I argue that the desire for payback has biosocial roots in cooperation, and that these habits are prerequisites for the development of human moral sensibilities. However, the explicit desire for payback, like anger in general, is morally ambiguous. Anger may be laudable insofar as it is tied to constructive efforts, but the desire to see another person suffer is in itself morally repugnant. Christian religious interpretations of payback further complicate the narrative, since unappealing instances of this desire are thought by some Christians to be nonetheless justified under the banner of God’s wrath.

In Anger and Forgiveness, Martha Nussbaum argues against the claim that the suffering of the wrongdoer restores, or partially restores, what was damaged by the wrongdoing. Making this mental mistake sets a person on “the road of payback,” and following this path is normatively problematic. What contribution can the canonical writings of Judaism, the Talmud and Midrash, make to the case against payback, when these writings reflect the view that a single deity establishes a divine justice in the world, such that ultimately the good are rewarded and the bad punished? This article argues, in light of recent research into rabbinic law and judicial process, as well as rabbinic theology of divine justice, that several components of these sources can help to meet the challenge. The texts recommend particular subjective states in the context of the human judiciary procedure and in consideration of divine justice, which do not intend “the suffering of the wrongdoer.” Rabbis seek authority, control over uncertainty, and a correct judicial procedure in their legal processes. Regarding the human relationship to the deity, rabbis both prescribe reverence and protest questionable divine acts based on their own ethical standards.