Simulation of a heat pump and an absorption refrigerating machine for the utilization of thermal energy in a data center

RELEVANCE. The thermal energy of a data center with an air-cooling system can be used, for example, to heat indoor air in winter. For this purpose, a heat exchanger can be installed, which transfers heat from the cooling system and uses it to heat the air, which then enters the building. A number of typical consumers of thermal energy from data centers are known: residential and office buildings, greenhouses. For example, Yandex opened a data center in a suburb of Helsinki in 2015. Thermal energy from the data center enters the heating system of residential buildings. At Facebook's data center in Lulea, Sweden, the heat generated by the servers is used to heat the air, which is then sent to Facebook's offices and neighboring buildings. In addition, the heat from the data center can be used to heat greenhouses and other agricultural facilities. In particular, in the Netherlands, heat from data centers is used to heat greenhouses where vegetables, flowers and other plants are grown.

THE PURPOSE. Simulation of the operating modes of a heat pump and an absorption refrigerating machine for the utilization of thermal energy in a data center.

METHODS. The simulation of the operating modes of a heat pump for the integration of a data center into a centralized heat supply system with the calculation of the heat balance and the determination of the coefficient of transformation of thermal energy, which is in the range of 3.4 - 4.5, depending on the design mode. Additionally, the simulation of the operating modes of an absorption refrigerating machine was carried out to cover the cooling load of the data center with the calculation of the thermal balance.

RESULTS. The constructed mathematical model is a model of a single heat pump, by combining which the level of coverage of the required heat output for the building will be achieved. The model is designed for the technological connection of a heat pump and a data center in the form of a "black box" concept, where the data center acts as a black box.

CONCLUSION. The integration of the heat pump into the thermal scheme of the data center is an urgent solution if the facility is located in the area of the district heating system. In turn, the use of absorption refrigerating machine with a cooling capacity of 2000 kW may have prospects, since groups of indoor chillers with a capacity of 2000 kW with external air condensers are used as a source of cold in typical data center refrigeration projects.

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