OPTIMAL PLANNING OF HYBRID POWER SYSTEM AT DIFFERENT ELECTRICITY TARIFFS

• Дата: 2023
• Автори: Kuznietsov, M., Karmazin, O.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2023
• Теми: hybrid power system; renewable energy; random process; tariff scenario.; гібридна енергосистема; відновлювані джерела енергії; випадковий процес; тарифний сценарій.
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/351
• Назва журналу: Vidnovluvana energetika

The aim of the paper is to study the impact of the random nature of renewable energy on the ability to achieve optimal balance of payments in the local power system, by choosing electricity pricing tariff scenarios. A mathematical model is proposed, which allows us to take into account the features of this system and the non-guaranteed solar or wind power. The components of the power balance are described as the decomposition of a certain random process, which distinguishes it from other models. The condition power system is the equality of the average expected power and its consumption. Random fluctuations in capacity determine the need for energy exchange between the system and the external grid, and the balance of payments is determined by the cost of imported and exported energy at different tariffs. The following possibilities are considered: constant tariff («flat»), tariffs for «time-of-use», special «green» tariff. The presence of a time-varying tariff shifts the balance of payments from equilibrium, depending on the composition of the renewable sources. The buying cost of solar energy decreases and sales increase unlike to the fixed tariff. For wind energy, the situation is reversed. The presence of a special tariff increases the income part of the payments; to balance it is enough to have less power by about 30 %, although the energy balance is disturbed. The presence of a 3-zone tariff compared to the 2-zone leads to some increase in payments throughout the year, while the loss for wind energy increases, and solar is becoming more profitable. However, the energy flows for predominantly solar generation are much higher. The combination of capacities allows us to reduce the total energy flows. The same result is provided by the use of energy accumulators - even a few hours of energy is able to halve or more dependence on the external network. The reliability of the simulated results is verified by comparison with real examples, discrepancies within 5-10 %. The proposed model allows us to choose the best tariff scenario for the certain power system, and assess the probabilities of energy and payments balances. Ref. 20, fig. 2, table. 9.