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As power generation systems with increasingly higher capacities are interconnected with distribution networks, a pressing need arises for a thorough analysis of their integration and the subsequent impacts on medium-voltage lines. This study conducts a comprehensive evaluation, encompassing both steady-state and transient behaviours, leading to a holistic assessment of a real-world biogas generation system integrated into a medium-voltage network. Although the methodology does not introduce revolutionary concepts, its detailed application on a real feeder under various operating conditions adds practical value to the existing body of knowledge. The methodology explores various aspects, including voltage profiles, load capacity, power losses, short-circuit currents, and protection coordination in steady-state conditions. Additionally, a transient analysis is performed to examine the system's response under fault conditions. This systematic approach provides a deep understanding of the system's behaviour across diverse operational scenarios, enriching the field with practical insights. The key contributions of this study include identifying the effects of distributed generation systems (DGSs) on short-circuit currents, protection coordination, and defining voltage levels that briefly exceed the CBEMA quality curve. The benefits of incorporating a generation system into a distribution network are discussed from various technical perspectives. In a peak demand scenario, with a 1.72 MW generation capacity, the phase current experiences a notable reduction of 35.78%. Concurrently, the minimum peak demand voltage increases from 12.62 to 12.83 kV compared to a nominal voltage of 12.7 kV. Furthermore, the contribution of the generation system to the short-circuit current remains minimal, staying below 4% even under the most adverse conditions. However, our findings reveal that voltage levels exceed the upper limit of the CBEMA quality curve briefly during a single-phase fault with generation, which could potentially damage electronic equipment connected to the grid. Nonetheless, the likelihood of encountering a single-phase grounding fault with zero resistance remains low. [ABSTRACT FROM AUTHOR]

Ecuador has significant solar potential, and the growing demand calls for sustainable energy solutions. Photovoltaic (PV) microgeneration in buildings is an ideal alternative. Identifying barriers to the widespread adoption of this technology is based on expert consultation and multi-criteria analysis, followed by proposals to overcome these challenges. The methodology of this study includes a systematic literature review (SLR), surveys of industry professionals, and statistical analysis of the collected data. The results highlight barriers such as the high initial cost, government-subsidized tariffs, bureaucratic processes and permits, ineffective regulations, limited awareness, lack of financing, distribution and operational network challenges, and insufficient government incentives. The proposed solutions suggest developing incentive policies to promote investment in PV microgeneration, training programs to enhance technical and cultural knowledge of solar energy, simplifying regulatory processes to facilitate project implementation, and providing accessible financing to reduce economic barriers. Additionally, the recommendations include the implementation of demonstration and outreach projects to showcase the feasibility and benefits of PV microgeneration, thus improving the social and technical acceptance of these systems. These actions aim to foster a faster and more effective energy transition in Ecuador. [ABSTRACT FROM AUTHOR]

Ecuador, like every country in the world, urgently requires a conversion of transportation to electric power, both for economic and environmental reasons. This paper focuses on the technical and economic feasibility of a solar-powered electric charging station equipped with battery storage in Cuenca, Ecuador. By reviewing current literature, we assess the environmental impact of electric mobility and its potential to reduce fossil fuel dependence and generate energy savings. The analysis encompasses various factors, including EV energy consumption, solar energy system sizing, energy production, and battery storage capacity. Key findings indicate that integrating solar PV systems with EV charging stations efficiently supports a reliable and sustainable energy supply. Simulation results reveal seasonal variations in solar generation, highlighting the importance of proper system sizing to maintain charging supply reliability and manage surplus generation. The economic analysis of three scenarios underscores the financial viability of implementing PV systems without battery storage, yielding a positive Internal Rate of Return (IRR) and Net Present Value (NPV). However, scenarios with battery storage present negative NPV and long investment return periods, impacting economic viability negatively. These insights underscore the need for a balanced design to ensure sustainability and economic feasibility in the transition to electric mobility. [ABSTRACT FROM AUTHOR]

A main restriction of renewables from intermittent sources is the mismatch between energy resource availability and energy requirements, especially when extensive power plants are producing at their highest potential causing huge energy surpluses. In these cases, excess power must be stored or curtailed. One alternative is increasing urban solar potential which could be integrated to feed electric buses directly or alternatively through hydrogen (H2) as an energy vector. H2 from renewable electricity can be stored and used directly or through fuel cells. This study aims to determine the H2 capability that could be achieved when integrating large-scale photovoltaic (PV) generation in urban areas. This analysis was carried out by determining the PV energy potentially generated by installing PV in Cuenca City downtown (Ecuador). Cuenca is in the process of adopting renewal of the public transport vehicle fleet, introducing a new model with an electric tram main network combined with "clean type buses". The conventional diesel urban transport could be replaced, establishing a required vehicle fleet of 475 buses spread over 29 routes, emitting 112 tons of CO2 and burning 11,175 gallons of diesel daily. Between the main findings, we concluded that the electricity that could be produced in the total roof area exceeds the actual demand in the study area by 5.5 times. Taking into account the energy surplus, it was determined that the available PV power will cover from 97% to 127% of the total demand necessary to mobilize the city bus fleet. The novelty of this work is the proposal of a combined methodology to find the potential to feed urban transport with urban solar power in cities, close to the equatorial line. [ABSTRACT FROM AUTHOR]

Several remote communities have limited electricity access and are mainly dependent on environmentally damaging fossil fuels. The installation of microgrid networks and green energy initiatives are currently addressing this issue. Thus, the techno‐economic assessment of a microgrid that comprises photovoltaic arrays, a micro‐hydro turbine, and diesel generation is proposed herein. Two scenarios are evaluated considering the inclusion or not of diesel generation. This model is performed in HOMER. The results demonstrate that the best option in economics is to invest in a PV/hydro/diesel microgrid, resulting in an net present cost of 2.33 M$, and a cost of energy of 0.194 $ kWh−1. Furthermore, to address diesel price uncertainties, a sensitivity analysis is carried out based on three different projected diesel prices. [ABSTRACT FROM AUTHOR]

Energy supply is becoming an important issue and electricity system reliability is sometimes difficult to ensure. Energy efficiency in buildings in use is a key element in the search for solutions to current energy problems. Many buildings in use can improve their energy consumption performance by implementing simple energy efficiency measures (EEM) in their facilities. After carrying out such actions, savings may be continued with just minimal maintenance. An additional key phase in classical energy studies is to define EEM to be implemented by the intervention of an external energy expert, since resident staff may not have the time, sufficient knowledge, nor experience in EEM. The energy expert intervention is of short duration (several days), and the total cost of the action may be moderate. In this paper, authors present several real examples implemented in three buildings on the Universitat Politècnica de València (UPV) campus after an external energy expert review. Savings, certified using real measured consumption before and after the action, represent around 10% of the total annual energy consumption in the buildings, and the payback of the EEM is approximately a few months. [ABSTRACT FROM AUTHOR]