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The reliance on imported fuels for electricity generation and internal transportation in insular electrical systems has historically posed a significant challenge due to their geographic isolation. The vulnerability of insular ecosystems to pollution has driven the need to transition toward renewable energy sources. Despite their inherent variability, wind and solar energy have gained acceptance. Integrating these renewable technologies into insular grids presents technical challenges that impact the quality of the power supply, particularly with the increasing presence of electric vehicles. Nevertheless, the batteries of these vehicles provide an opportunity to enhance network performance. This article introduces an innovative power smoothing technique that utilizes electric vehicle batteries to optimize self-consumption and reduce power fluctuations. The proposed method is an enhanced version of the ramp-rate energy smoothing method, incorporating adaptability through real-time control of the ramp-rate using fuzzy logic. It employs an aggregated model of lithium-ion batteries with a bidirectional power electronic converter. Experimental validation is carried out in the Micro-Grid Laboratory of the University of Cuenca, Ecuador. Experimental results demonstrate a significant 14% reduction in energy generation variability, resulting in a more stable electrical supply profile. Additionally, there is a marginal improvement in energy delivery, with an additional injection of 0.23 kWh compared to scenarios without the participation of electric vehicle batteries in power smoothing tasks. These findings support the effectiveness of the proposed approach in optimizing the integration of intermittent renewable generators and electric vehicle charging in insular energy systems. [ABSTRACT FROM AUTHOR]

Nowadays, energy decarbonization due to integrating renewable energy sources presents important challenges to overcome. The intermittent nature of photovoltaic systems reduces power quality by producing voltage variations and frequency deviations in electrical system networks, especially in weak and isolated distribution systems in developing countries. This paper presents a power smoothing method for improving the low-pass filter and moving average for grid-connected photovoltaic systems. This novel method includes state-of-charge monitoring control of the supercapacitor's energy storage system to reduce the fluctuations of photovoltaic power at the point of common coupling. A case study for a microgrid in a high-altitude city in Ecuador is presented with exhaustive laboratory tests using real data. This research aims to improve energy power quality in electrical distribution systems to cope with the growth of renewable penetration. The results demonstrate significant power quality and stability improvements achieved through the proposed method. For instance, the power smoothing method effectively reduced power fluctuations by 16.7% with the low-pass filter, 14.05% with the ramp-rate filter, and 9.7% with the moving average filter. [ABSTRACT FROM AUTHOR]

Sustainable development reached a new energy paradigm in recent decades, by promoting renewable generation technologies. The present study performs a techno‐economic analysis of several hybrid energy systems that combine wind generators, photovoltaic systems, hydrokinetic turbines, lead acid batteries, and diesel generators in southern Ecuador. From real data, the sizing optimization of each renewable system was done under three proposed energy control algorithms. Then, the combinations of renewable systems are compared based on costs, energy, and environment. Additionally, this study includes several sensitivity analyzes varying the cost of the components and fuel, minimum state of charge in batteries, scaled electric load and time step to better understand the impact caused in each renewable hybrid system. The results show that a system composed of three renewable sources under load following and cycle charging energy controls, is cheaper and less polluting with respect to any combination of sources proposed. In addition to this, the systems that include photovoltaic systems and diesel generators present lower cost, 0.36 US$/kWh in the best case. To reduce the operability of the diesel generator, load following energy control is recommended. However, if diesel generator is removed, the resulting cost of 100% renewable systems increases considerably, reaching 0.88 US$/kWh. The results also show that, the variation in the capital cost of the components is directly proportional to the net present cost and cost of energy variation. Moreover, it is possible to reduce the cost of the system by discharging the batteries below their minimum state of charge. Finally, the results are more accurate when using a time step of 5 minutes. [ABSTRACT FROM AUTHOR]

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The growing reliance on hydroelectric power and the risk of future droughts pose significant challenges for power systems, especially in developing countries. To address these challenges, comprehensive long-term energy planning is essential. This paper proposes an optimized electrical system for 2050, using Ecuador as a case study. For forecasting electricity demand, a Neuro-Fuzzy Adaptive Inference System is employed, utilizing real historical data. Subsequently, the EnergyPlan software constructs a long-term energy consumption model, exploring three scenarios based on Ecuador's energy potential. The first scenario represents a 'business as usual' approach, mirroring the current trend in the Ecuadorian electricity system. In contrast to the second scenario, it encompasses a broader range of renewable sources, including offshore wind, pumped storage, biomass, and geothermal energy. The third scenario extends the second one by incorporating demand response systems, such as vehicle-to-grid and hydrogen-to-grid technologies. In terms of novelty, this study highlights the innovative use of the Neuro-Fuzzy Adaptive Inference System for demand forecasting, along with a comprehensive exploration of multiple scenarios to optimize the electrical system. Research findings indicate that the integration of these new renewable energy sources not only reduces electricity import costs but also ensures surplus electricity production. Consequently, it is anticipated that the 2050 electricity system will reduce its dependence on hydroelectric energy while adopting photovoltaic and wind energy with penetration rates of 65 %, 11.2 %, and 9 %, respectively. This transition will be facilitated by a pumped storage system with a 28 % penetration rate and enhanced connectivity with neighboring countries, enabling the seamless integration of electric and hydrogen vehicles. [Display omitted] • Introducing a long-term electricity demand forecast with adaptive neuro-fuzzy inference. • An energy schedule for Ecuador in 2050 is derived from the demand forecast. • Renewable sources reduce costs, surplus electricity, and imports, enabling a 100 % renewable system. • By 2050, Ecuador's electrical system will rely on hydro, photovoltaic, wind, and pumped hydro power. • The optimized Ecuadorian electrical system will enable V2G and H2G integration in 2050. [ABSTRACT FROM AUTHOR]

This article presents a comparison of two alternative systems to supply the traction power of a tramway in Cuenca–Ecuador. Each system studies the effective combination of supercapacitors, lithium ion batteries and proton exchange membrane fuel cells (SC/LIB/PEMFC) on board. The first system uses renewable sources (PV/HKT/GB/Grid) supplying the on-board systems through the existing grid and hydrogen charging stations. While the second system uses only grid power from a single point of charge, leaving the tramway without any external connection point throughout their journey. The energy and economic analyses are based on the capacity of each system to supply the load and the resources used. The results show that the new proposed control systems, by means of the analysed configurations made up of different control states, are always capable of perfectly supplying the power required by the tramway throughout their journey. However, when using energy from renewable sources, hydrogen consumption decreases by 4.27% with respect to the grid on each round trip, with a lower net present cost. Furthermore, in the first proposed system, the depth of discharge in SC and LIB is greater. • Energy control systems based on fuel cell for a hybrid tramway in Ecuador. • Renewable components (photovoltaic, hydrokinetic and biomass). • All components are charged with the braking power of the tramway. • The study includes technical-economic analysis of two proposed systems. [ABSTRACT FROM AUTHOR]

This paper analyzes the impact on an off-grid renewable hybrid system composed of photovoltaic energy, hydrokinetic turbines, batteries and biomass gasifiers, using various types of biomass in order to determine the optimal configuration of the system located in southern Ecuador. Three types of energy dispatch, charge cycle, load following and combined cycle have been proposed with the objective of determining new patterns on the behavior of sources with respect to electric demand. The biomass used as an energy resource produces electricity through a biomass gasifier that feeds a microturbine. Considering the types of biomass consumed by the gasifier, the items such as net present cost and cost of energy have been analyzed for the different types of control. Sensitivity studies indicate the increase in the cost of the system by increasing the minimum state of charge in the batteries. However, this increase reduces biomass consumption and CO 2 emissions. Finally, the variation of the cost in the components influences the total cost of the system, being the fuel and the photovoltaic system the systems that have the highest sensitivity, the results have shown that the renewable system is able to supply the demand without violating any norm. • Off-grid renewable hybrid system including biomass gasifiers in Ecuador. • Three types of energy dispatch, charge cycle, load following and combined cycle. • Electricity through a biomass gasifier that feeds a microturbine. • Net present cost and cost of energy have been analyzed. • The biomass and the photovoltaic systems have the highest sensitivity. [ABSTRACT FROM AUTHOR]