The paper considers a possible method of technical diagnostics of electrical equipment of power supply systems and electrical substations based on the fuzzy sets and fuzzy logic. it is shown that, based on the matrix of fuzzy relationships, one can make a plausible enough prediction about possible malfunctions and causes of failures. the prerequisites for this analysis are the current condition (state) of the electrical equipment and expert assessments of diagnostic signs. the paper shows the comparison made using the features scale of saaty, in accordance with nine degrees of preference.

At the core of fuzzy expert assessments is an attempt to formalize linguistic information, namely linguistic variables whose meanings can be words or phrases. the paper presents a complete range of preconditioned defects consisting of m factors and their corresponding space conclusions as to the causes of these malfunctions (defects) of n symptoms. fuzzy causal relations in the space of underlying factors are established between the assumptions and conclusions of the experts. the resulting system of equations is solved by the method based on the composition of fuzzy conclusions. possible failures are ranked according to the experts’ preference, which reveals the most significant symptoms of malfunctioning and allows arriving at the conclusion as to the future operation of the facility. the validity of the provisions of the method presented is confirmed by appropriate calculations, which demonstrates the correct behavior of the model concerning the transformer equipment.

It is shown that in case of the fuzzy symptoms occurrence and evaluation of these features by a scale of preferences, it is possible to conclude about the further operation of electrical equipment or its withdrawal for repair. thus, the mathematical model based on the fuzzy relations of symptoms selected using the experts’ estimations contains elements of predicting the possible failures of power systems electrical equipment.

The present contribution deals with an ongoing italian research which includes several steps and it is approaching to its final stage. the main goal is analysing and testing the feasibility of municipal waste reuse for designing building envelopes for near zero Energy Buildings (nzEB), so as to contribute to the decreasing demand for energy and improve eco-friendly waste management in urban areas. first, prefab building components have been designed using selected waste and their thermal and acoustic behaviours have been calculated, according to the European rules; then the economic costs of the obtained building envelopes have been assessed and compared to common building structures to verify their possible appeal on the italian market, and finally the components have been assembled in the project for a small nzEB building: a didactic classroom for the mira porte primary school (venice, italy).

This paper refers to the in-depth elaboration of the project, mainly concerning fire and pollut- ant protection, and it focuses on the reliability check of the Building information modeling (Bim) parametric model, especially as concerns non-conventional materials and components. the relative building energy behaviour has been obtained exporting the Bim energy simulation model using the Ec770 integrated design for revit plug-in. finally, a comparison between the results obtained with the traditional energy assessment (according to d.m. 26/06/2015) and those using the Bim model has been made to evaluate the interoperability between architectural modeling software and the energy simulation one.

The Atacama Desert in Northern Chile features the highest solar radiation on continental soil worldwide, ranging within 2,500–3,400 kWh/m2/year, with UV-B radiation levels 65% above average European. This desert covers an extension over 105,000 km2 receiving more than 4,000 hours of sunshine yearly, and hosts large reserves of copper, lithium, molybdenum and other metallic and non-metallic minerals. Thus, the Chilean mining industry accounts for more than 30% of the total electricity consumption in the country. During the last 3 years major investments on solar photovoltaic (PV) plants have taken place at the Atacama Desert, driven by the drastic drop in the cost of PV technology, and incentives provided by the new Energy 2050 Roadmap set by the Chilean government, with view to fostering the introduction of renewable energy sources in the electricity market. The Chilean electricity system is composed of two connected grids, namely the Greater Northern Network (SING) and the Central Network (SIC), with a total installed capacity of nearly 21 GW. The SING network is mostly composed of thermoelectric power plants, whereas the SIC network features a significant share of hydroelectric plants, leading to different carbon footprint, namely 0.9 and 0.3 ton CO2eq/MWh, at SING and SIC, respectively. At the end of 2017, those grids were connected to meet the current 80 TWh/year national demand. Massive introduction of PV electricity generation plants at the Atacama Desert is foreseen in the near future, to reach a projected share around 25% by 2050. Within this framework, this paper presents novel results on the effect of solar energy on the environmental profile of electricity in Chile in a midterm scenario, using a life cycle assessment approach, under conditions of drastic reductions in water availability due to climate change. Results show that PV systems make a significant contribution to environmental impacts associated to electricity generation in the national mix by 2050, mainly in ozone layer depletion, abiotic depletion, global warming, acidification, and photochemical oxidation potentials impact categories, mainly from upstream transport and cell manufacturing. The extent of those impacts could increase significantly if the PV lifespan decreases due to cells degradation as a result of harsh environmental conditions, highlighting the need for reliable data on this key parameter.

In the quest for cost-effective production of biodiesel, selection of cheap feedstocks and catalysts play the significant role. Waste cooking oil is abundantly available from all types of restaurants throughout the world. Catalyst selected for this feedstock should be heterogeneous. Coconut coir, which is bio- mass and source of carbon, was selected for its study as a catalyst for biodiesel production. This paper is based on a comparison of a solid catalyst by two processes: (i) sulphonation of coconut coir char (pyrolysed at 500°C for 3 hours) and (ii) digestion of pyrolysed coconut coir with 10% NaOH at 70°C for 4 hours followed by sulphonation. Comparison of both the solid catalysts thus prepared was done based on their physical properties, total acid density, SEM and FT-IR analysis. The higher percentage of fixed carbon content, higher acid density and BET surface area, better morphological surface and pronounced presence of sulphonic (-SO3H), carboxylic (-COOH) and hydroxyl (-OH) groups favours the selection of catalyst prepared by the second method for further study for biodiesel formation using waste cooking oil as the feedstock. Effects of various parameters on biodiesel production: alcohol to oil ratio (A:O), time of reaction, reaction temperature and catalyst loading were studied. At the optimised conditions, the biodiesel conversion was 90.12%. Biodiesel produced by the method was characterised regarding fuel properties and were found close with the standard values.

Society has done little to modernize energy delivery or take advantage of proven, commonly available technology. in the past, change was driven by regulated entities with an exclusive franchise. today, however, disruptors come from outside of the power sector – a phenomenon that is changing the grid. the grid of the future will provide an open platform, similar to a state-owned interstate that allows access to all. generation, storage, and load elements will be self-registering building blocks, similar to the concept of all ‘lego’ sets being compatible. elements will be connected by providers or even consumers, they will self-register, and interact with each other optimizing grid performance with respect to economics, efficiency, adequacy, and reliability. the ubiquitous grid will encompass not only electric, gas, and water, but other services that either we’ve already come to rely upon or haven’t even considered yet. is this farewell to the grid as we know it? the exclusive franchise model that has been around for more than a century might not be as long lived as expected.

In Chile, during the last 40 years the municipal solid waste (msW) generation rate has shown a 4-fold increase due to population growth, fast urbanization and improved material standards. as in most developing countries, this trend is expected to continue as economic policies foster greater industrial investment and increases in domestic consumption.

Currently, msW are landfilled near ever expanding urban areas, leading to growing public concerns, and prompting new control legislation. up-to-date msW management practises are being promoted in order to maximise waste valorisation, including recycling, and waste-to-energy, within a circular economy strategy. However, new resource consumption, waste streams, air emissions and effluents may arise when changing from a linear to a circular economy model. Therefore, environmental performance of alternative scenarios must take into consideration the complete life cycle to avoid problem shifting. Within this context, this paper presents a case study of three alternative waste-to energy scenarios, as part of a circular economy strategy, involving combustion, gasification, and landfill biogas, at the Bio Bio region in southern Chile. This is an industrial region housing over 2 million inhabitants and generating more than one million tonnes of msW per year. The study assesses waste-to energy alternatives considering an integrated waste management life cycle approach. Boundaries include waste collection, transport, pre-treatment processes, by-products generation, and heat/power production. msW transport, recycling rates, chemical compositions, and calorific values, were obtained from primary sources, whereas energy conversion efficiencies and other data gaps were estimated from the ecoinvent database. results provide a complete view of the environmental performance of each alternative scenario, including potential climate change effects and other environmental impacts, and also the positive contributions of material and energy recovery. This work illustrates the value of life cycle assessment in the context of decision making concerning circular economy scenarios.