Cuba is traditionally considered a country with an underdeveloped industry. The share of the mining and metallurgical industries in the gross industrial production of the republic is small – about 3 % of GDP. The development of deposits and the extraction of nickel ores is an important sector of the economy of the Republic of Cuba, since the largest reserves of nickel and cobalt on the North American continent are located on the territory of the country. The development of the country energy system can serve as a growth factor in this sector of the economy. Due to climatic features and impossibility of integrating new capacities into the energy system through the construction of hydroelectric power plants, solar energy is a promising direction. Determining the feasibility of using solar tracking systems to increase the generation of electricity from solar power plants is one of the main challenges faced by engineers and renewable energy specialists. Currently, there are no solar tracking systems in Cuba that can provide information to assess the effectiveness of this technology in the country. The lack of the necessary technologies, as well as the high cost of developing solar power plants with tracking systems, limit the widespread introduction of such complexes. Hence follows the task of creating an inexpensive experimental model that allows assessing the effectiveness of tracking systems in specific weather conditions of the Republic of Cuba. This model will allow in future to increase the efficiency of electrical complexes with solar power plants, which provide power supply to the objects of the mineral resource complex and other regions.

Devices operating in complete energy autonomy are multiplying: small fixed signaling applications or sensors often operating in a network. To ensure operation for a substantial period, for applications with difficult physical access, a means of storing electrical energy must be included in the system. The battery remains the most deployed solution. Lead-acid batteries still have a significant share of this market due to the maturity of their technology. However, even by sizing all the system elements according to the needs and the available renewable energy, some failure occurs. The battery is the weak element. It can be quickly discharged when the renewable energy source is no longer present for a while. It can also be overloaded or subjected to high temperatures, which affects its longevity. This paper presents a suggested improvement for these systems, systematically adding extra devices to reduce excess charges and heat and allowing the battery use at lower charges. The interest of this strategy is presented by comparing the number of days of system failure and the consequences for battery aging. To demonstrate the interest of the proposed improvement track, a colored Petri net is deployed to model the battery degradation parameters evolution, in order to compare them.

Designed to store and discharge electrical energy, rechargeable batteries consist of elementary storage cell assemblies. Aging is affected by various aggravating factors, mainly temperature. There are many electric or electrochemical models which describe their operation. Most standard models do not consider the aging phenomena of batteries and their consequences, while batteries deteriorate when used or stored. Precisely, most battery models do not simulate the influence of cell aging on other cells. The model presented in this paper incorporates aging and the effects of mutual interactions between cells. The model can be established based on four measurement points on the cell characteristic curve and allows the simulation of a single cell’s or multiple coupled cells’ behavior. The model can then be easily implemented in simulation software like Matlab.

The problem of increasing the efficiency of existing power plants is relevant for many countries. Solar power plants built at the end of the 20th century require, as their shelf lives have now expired, not only the replacement of the solar modules, but also the modernization of their component composition. This is due to the requirements to improve the efficiency of power plants to ensure the expansion of renewable energy technologies. This article presents a technical and economic analysis of the choice of solar power plant modernization method, which consists of (1) a method for calculating the amount of power generation; (2) the modeling of solar power plants under specific climatic conditions; (3) the analysis of electricity generation using different types of PV modules and solar radiation trapping technologies in Matlab/Simulink; and (4) the technical and economic analysis of a 2.5 MW solar power plant in the Republic of Cuba (in operation since 2015), for which four different modernization options were considered. All the scenarios differ in the depth of modernization; the results of the analysis were compared with the existing plant. The results of the study showed that the different modernization scenarios respond differently to changes in the inputted technical and economic parameters (cost per kWh, inflation rate, losses, and power plant efficiency). The maximum NPV deviations among the considered scenarios are: a 1% increase in inflation reduces NPV by 2%; a decrease in losses from 20% to 10% increases the NPV by 2.5%; a change in cost from EUR 0.05 to EUR 0.1 increases the NPV by more than 3.5 times. The dependence of the economic results was also tested as a function of three factors: solar module efficiency, inflation, and the price per 1 kWh. It was found that the greatest influence on the NPV of the proposed model is the price per 1 kWh. Based on this analysis, an algorithm was developed to choose the most effective scenario for the conditions of the Republic of Cuba for the modernization of the existing power plants.

Renewable power sources (RPS) play an ever growing role in power production. With the green power cost decreasing, the RPS share (including hydro power plants) in power production grows fast. Using RPS in supplying power to various facilities reduces the CO2 emission into atmosphere, thus...

Annotation. Today, the efficiency of solar power plants in the Republic of Cuba is low, despite the high level of technology development in this area. The article presents the results of the analysis of the potential of solar energy in the territory of the Republic of Cuba. This paper presents the results of experimental studies, the purpose of which is to increase the efficiency of using photovoltaic stations. The developed two-axis sun tracking system is described. This tracking system increases the conversion efficiency of solar energy into electrical energy in photovoltaic modules.