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The paper deals with the impact of the technological break duration during the cold storage cycle on the energy demand of the cold store for vegetables and fruit and the temperature distribution in the ground under the cold store. The studied facility was a two-chamber vegetable cold store located in southern Poland used to store carrots (Daucus carota) for nine months a year. The experiments were conducted for 12 months (01.05.2017–30.04.2018). The technological break during this period lasted three months (from 1 July 2018 to 30 September 2018). Continuous measurements (with 1-h frequency) were made in order to determine the boundary conditions for numerical analysis. The measured parameters included indoor air temperature, outdoor air temperature, ground temperature under the building and in its vicinity. There were 22 measuring points andPT100 sensors were used. The numerical analysis was based on the elementary balances method. WUFIplus® software was used as a calculation supporting tool. The numerical analysis was conducted for 14 calculation variants, with different duration of technological break. The calculation model validation was performed and the results showed a good correlation with the experimental data. The results of experimental studies and of calculations showed a significant impact of the technological break duration on the soil distribution in the ground and the building energy demand. A technological break of less than 4 weeks is the most optimal in the summer. The technological break longer than 4 weeks significantly affects the cooling energy demand in the first days of the cooling cycle and significantly extends the time necessary for the ground and the floor to reach the optimum temperature. The analysis of the floor temperature results (points A1–C1) showed that the technological break longer than four weeks causes the average floor temperature to exceed 4.0 °C. Therefore, the optimum solution is technological break lasting 7–35 days. Absence of technological break results in a decrease of energy gains from the ground by 20% relative to a three-month technological break. The impact of technological break duration was clearly seen in terms of energy losses from the cold store to the ground. In case of a 91-day technological break, the energy losses to the ground were 1289.5 kWh/a, while in case of absence of technological break this value was ninefold lower (147.5 kWh/a). [ABSTRACT FROM AUTHOR]

This paper presents an analysis of thermal interaction between a building and surrounding soil. The examined building was located in southern Poland. Measurements of selected indoor and outdoor air temperature parameters were made in order to determine the boundary conditions. The soil temperature measurements were conducted at 42 points. The analysis of results is divided into four periods: summer, autumn, winter, and spring. The analysis show that weather conditions significantly affect the temperature in soil, but the range of residential building impact decreases with distance, and it varies depending on the season. The residential building impact on the soil temperature is in the range of 1.2–3.3 m. This paper also includes a study of the heat flow direction in soil and a quantitative estimate of heat exchange between a building and the soil. The greatest energy losses 2082 kWh (21.24 kWh/m2) from the building to the soil were recorded in winter. In spring, the energy losses were reduced by about 38% as compared with the energy losses in winter, and the energy losses in spring were comparable to autumn. [ABSTRACT FROM AUTHOR]