ANALYSIS OF THE DISTRICT HEATING SYSTEM WITH THE SEASONAL THERMAL ENERGY STORAGE SYSTEM TOGETHER WITH THE SYSTEM OF HYDROGEN PRODUCTION AND UTILISATION

• Дата: 2020
• Автор: Lysak, O.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2020
• Теми: heating; hydrogen; renewable energy; seasonal thermal energy storage; geothermal energy.; водень; відновлювана енергетика; опалення; сезонне акумулювання; геотермальна енергетика.
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/271
• Назва журналу: Vidnovluvana energetika

The aim of the article is to analyze the application of the district heating system using the underground seasonal thermal energy storage (STES) together with the system of production and consumption of hydrogen. The energy for both cases is provided by renewable energy sources (RES). Produced heat, electricity and hydrogen is used to provide energy for the residential buildings and related infrastructure. Regarding the ratio of heat supply of each system, the STES is the main source of heat supply, and the hydrogen system is an auxiliary energy source designed to provide heat consumption during the "peak" load of the district heating system. This paper shows the use of hydrogen due to the need to abandon conventional energy sources, in particular natural gas, as a “peak” and backup energy source of district heating systems. Although the main part of the article is devoted to the issue of district heating systems, the paper also analyzes other elements of energy supply of residential buildings and related infrastructure. In particular, attention is paid to variable RES, which are characterized by the variable output of electricity and heat production through time, and their connection to the power grid. It is also shown how the excess electricity from RES serves as a source for hydrogen generation. The obtained hydrogen is to be used both for the hydrogen heating system and for the potential fuel supply of hydrogen vehicles. Since fuel cells are used in the process of heat generation from hydrogen utilization, in addition to heat, such systems are able to generate electricity. The paper provides the classification of STES describing both their schemes and, their operational principles. Their comparison of different STES is also given. The preliminary analysis of the economic feasibility of the district heating systems with STES was conducted. It was done through the comparison of the current cost of the convenient district heating system, which uses natural gas in Ukraine, and the levelized cost of energy (LCOE) from the district heating system, which includes the STES. The economic analysis showed that in the case of Ukraine the LCEO of the district heating systems using borehole thermal energy storage is 80…200 % more expensive than the cost of the convenient district heating. At the same time, the LCOE of the district heating systems using pit thermal energy storage may be 20 % cheaper but the installation of such systems requires significant initial investment. Ref. 50, table. 3, fig 4.