Efficiency of a Compressor Heat Pump System in Different Cycle Designs: A Simulation Study for Low-Enthalpy Geothermal Resources

Abstract

The development of district heating systems results in a search for alternative heat sources. One of these is low-enthalpy geothermic energy, more available than traditional geothermal energy. However, utilization of these resources is difficult, due to the low quality of the produced heat. To utilize them, the heat pump system can be used. Such a system was designed for this case study of a city in a region of the Polish Lowlands. The data necessary for the design came from the project of the borehole and operational parameters of the existing heating plant. Four heat pump-cycle designs were proposed, modeled, and simulated using Ebsilon software. Afterward, the designs were optimized to achieve maximum coefficient of performance (COP) value. As a result of the simulation, the efficiency of each design was determined and the seasonal COP value was calculated with the annual measured heat demand of the plant. The system based on the cascade design proved the most efficient, with a seasonal COP of 7.19. The seasonal COP for the remaining basic, subcooling, and regenerator variants was 5.61, 3.73, and 5.60, respectively. The annual heat production of the designed system (22,196 MWh) was calculated based on the thermal power of the designed system and historical demand data. This paper presents a simulation methodology for assessment of the efficiency and feasibility of a heat pump system in district heating.

The Efficiency Improvement of the Device Based on the Example of a High Building Facade Washer in the Area of Industry 4.0

“…In the case of facade washing machines, efficiency determines the washing costs and profitability of a project consisting of the purchase of a machine for a building or the provision of facade cleaning services by specialized entities. The basic measures to improve the efficiency of the washing machine for washing the washing facade may be increasing the working width, increasing the rotational speed of the brush or other washing module, increasing the speed of the machine moving along the facade, reducing technological downtime, shortening the time of assembly and disassembly, or the use of a specially prepared washing medium [17][18][19].…”

Experimental Investigation of the Improvement Potential of a Heat Pump Equipped with a Two-Phase Ejector

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