The use of renewable energy sources in buildings is more and more common (both for heating and cooling purposes, as well as electricity generation). The paper focuses on the thermal comfort tests in two buildings: the traditional one (that uses non-renewable sources of energy) and the modern intelligent building “Energis” of Kielce University of Technology. The thermal sensations of students in these two buildings have been compared based on the questionnaire survey and conclusions have been drawn regarding the differences between the feelings of thermal comfort in those two buildings. Apart from subjective feelings of the volunteers, the measurements of indoor air parameters were conducted in both buildings and have been presented in the paper.

The paper presents experimental results of a study on indoor thermal environment in selected educational buildings located in the city of Kielce (Poland). The volunteers in the investigated rooms were asked to fill in the anonymous questionnaires containing questions on their thermal sensation, thermal preference and thermal acceptability votes as well as humidity assessment and humidity preference votes. In total, 83 people completed the questionnaires. Simultaneously, the indoor air parameters were measured with a microlimate meter equipped with precision sensors to measure air and globe temperatures, air velocity and relative humidity. The analysis of the obtained results provides information on the subjective assessment of the thermal environment in the considered rooms. It allowed to assess whether the guidelines given in the standard are consistent with the real feeling of comfort of the respondents. Research in the performed scope has shown that the feelings of the respondents and the standard guidelines diverge. It was noticed that that the subjects definitely felt better in the rooms where the temperature was around 22.5°C. The subjects felt worse at the temperature of 25.3°C and the worst of 27.6°C.

In the modern world, a person spends most of his life indoors. That is why it is so important to create optimal conditions for the internal environment. Research on thermal comfort and subjective feeling of people inside the building can help in this. The article discusses two methods that are used in research on thermal sensations. This makes it possible to know the thermal assessment of people and then compare this result with the calculated PMV value, which is calculated using the formula from ISO 7730 standard.

The issue of thermal comfort and its subjective feelings inside a building is becoming more and more important in the modern world. It is caused by the desire to create optimal conditions in places where people stay. The article presents two methods, indirect and direct, which are typically used in the research projects. These methods enable to assess the thermal sensations of people and compare the feelings of the respondents with the value of PMV (the value of human thermal sensations) calculated using the formula from the ISO 7730 standard and the questionnaire surveys.