Reconstruction of the heating system of Preschool N4 in Lviv using alternative energy sources
Students Name: Panasiuk Nazarii Orestovych
Qualification Level: magister
Speciality: Heat and Gas Supply and Ventilation
Institute: Institute of Civil Engineering and Building Systems
Mode of Study: full
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: In this master’s thesis, the reconstruction of the system for ensuring the thermal condition of Preschool educational institution (PEI) No. 4 in Lviv was developed using alternative energy sources. Reconstruction of public real estate over the past five years had an average growth rate of 8.9%. State boards are turning more to redeveloped properties rather than new construction due to a number of factors, including a lack of available space and the time it takes to start something from scratch. Children’s preschool educational institution No. 4 in the city of Lviv is intended for the stay of children aged 3-7 years. This is a normalized three-story building, which additionally has basement and attic floors equipped for the needs of PEI No. 4. The height of the building above ground is 14.1 m. During the reconstruction of the building, a roof boiler room with equipment selected for it was designed for PEI No. 4. The building is located in the central part of the city of Lviv and has high pressure cold water supply. Additional premises of PEI No. 4 include a laundry room and a kitchen equipped with electricity to ensure a high-quality educational process. In addition, there are premises for a music and physical culture hall. The total area of the building is 1351 m2. PEI No. 4 is intended for the simultaneous stay of 90 people. Year of construction – 1990 (built according to the typical T8 project). The scientific part of the work is that heat pumps were used as an alternative source of energy. Heat pumps offer an energy-efficient alternative to furnaces and air conditioners for any climate. Heat pumps use electricity to transfer heat from a cool room to a warm one, making a cool room cooler and a warm room warmer. During the heating season, heat pumps transfer heat from the coolness outside into your warm home. During the cooling season, heat pumps move heat from your home to the outside. Because they transfer heat rather than produce heat, heat pumps can effectively provide a comfortable temperature in your home. Air heat pumps are used in the project. The most common type of heat pump is an air-to-air heat pump, which transfers heat between your home and the outside air. A modern heat pump can reduce electricity consumption for heating by around 50% compared to electric resistance heating such as furnaces and slab heaters. High-efficiency heat pumps also dehumidify better than standard central air conditioners, resulting in lower energy consumption and greater cooling comfort in the summer months. Two hydraulic modules of the SEHVX64BW heat pump with a heat capacity of 64 kW each are installed in the room of the heat generator. Each heat pump is connected to the hydraulic modules by separate copper pipes. Hydromodules are equipped with Freon-water type heat exchangers and additional, auxiliary equipment. After the hydro modules, the heated water of the heat supply system enters the hydro arrow. Circulation between the hydraulic modules and the hydraulic arrow is created by pumps located in the hydraulic modules. Heat pumps have energy efficiency class A+, and their energy efficiency coefficient is: EER 3.5 and COP 3.93, respectively. With the help of modern Mastertherm software, you can calculate the cost savings from installed heat pumps. Since the software is of Czech production, the result in funds is obtained in kroner, which is converted into hryvnia at the rate of 1 Kc = 1.59 UAN. The following data was entered into the program: - the price of natural gas for a budget organization is UAH 16,553.89 per 1,000 m3; - the price of electricity is UAH 1.68. (with VAT) for 1 kW?h. In particular, for the calculation, it was assumed that, on average, PEI No. 4 uses 5,000 kWh of electricity per year. A diagram of the annual cost of heating the building with heat losses of 63 kW was obtained. That is, cost savings compared to natural gas can reach savings of more than 1.5 times, namely 35%. During the reconstruction of the heating system of Preschool No. 4 in Lviv using alternative energy sources, the following energy saving measures were achieved: 1. The house was insulated, which helped save 34% of thermal energy annually; 2. The designed heating system has installed dynamic valves for balancing and thermal regulation of the coolant. According to the manufacturer Danfoss, the use of RA-DV valves allows any heating system to be used more efficiently by at least 5%; 3. All pipelines and air ducts of the building are thermally insulated, which increases energy savings by approximately 5%; 4. The equipment of the heat generator is certified with an energy efficiency class of at least A+, which also makes it possible to motivate the efficiency of the building, according to the reference literature, which is approximately 15% higher; 5. Combining a heat generator with heat pumps, taking into account the COP coefficient based on monetary costs, allows you to increase the building’s energy savings by 35%. As a result of the reconstruction of PEI No. 4, 94% energy savings were achieved in providing thermal conditions compared to the non-reconstructed building. It is necessary to pay attention that the remaining 6% can be achieved due to the reconstruction of the water network systems of cold water supply, sewerage and/or electricity supply. The object of the study is the reconstruction of the system for ensuring the thermal state of Preschool educational institution No. 4 in Lviv using alternative energy sources. The subjects of the study are systems for ensuring the thermal condition of Preschool No. 4 in Lviv using alternative energy sources. The purpose of the study: to investigate the systems for ensuring the thermal condition of Preschool No. 4 in Lviv using alternative energy sources and to analyze the possibilities of saving the building after reconstruction. Key words - reconstruction, thermal modernization, insulation, heat loss, heating system, ventilation system, energy saving, heat pumps.