Increasing the efficiency of seasonal heat accumulator operation
DOI:
https://doi.org/10.31548/energiya4(86).2026.148Keywords:
thermal energy, seasonal storage, operating modes, energy efficiencyAbstract
The use of seasonal thermal accumulators (TES) is becoming relevant due to the involvement of cogeneration units in balancing energy systems. The study is devoted to substantiating the operating modes of seasonal TAs in order to increase their energy efficiency and was carried out using a computational and analytical method using the basic equations of heat transfer theory. The influence of the main thermal characteristics of the TES on heat losses to the external environment has been studied. It has been shown that one of the main parameters that determine these losses is the difference in temperature between the outside air and the heat carrier of the TES. The thermal efficiency of TES decreases with the increase in the difference in these temperatures due to the increase in heat loss to the external environment. Analysis of the obtained calculation results demonstrates that long-term storage of accumulated thermal energy in seasonal TES is accompanied by a loss of energy and temperature potential: heat losses during storage for 120 days are three times higher than losses in the first 30 days, and the temperature also decreases almost three times when comparing these periods. To assess the impact of seasonal TA operating modes on heat energy losses to the environment, the relative heat loss coefficient was used. Extended storage and supply of thermal energy to consumers with an increase in the temperature difference due to a decrease in the average daily outdoor temperature leads to additional heat losses to the environment and a decrease in the energy efficiency of the heating system. Measures are proposed to optimize the operating modes of the seasonal TES, which will ensure a significant reduction in heat loss and increase its energy efficiency. The obtained research results are expedient to be used in the operation of seasonal TES of CHPs operating in maneuvering modes of providing auxiliary services in the power system.
Recieved: 29.05.2026. Recieved: 05.08.2026. Accepted: 20.08.2026.
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