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Energy consumption in buildings is a large share of the world's total end use of energy. Residential and commercial buildings require approximately 35% of the end use of energy, in addition to this energy is used for buildings also in the industry. In this context the paper proposes the energetically analysis for a small-scale modern station, providing solar heat to a solar house with 2 floors, located in the city of Braşov, România. The paper describes the location, size and thermal regime of the solar house; there are also presented the heating system facility and equipment components, designed for the solar house located in Transilvania University Campus. Based on the achieved simulations it is shown that compared to the ordinary control the energetically-based control provides remarkable advantages and savings concerning the auxiliary heating energy. This result should be valid for any systems similar to the particular one in Braşov.

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This paper proposes a study on the estimation of daily solar irradiation (global and diffuse irradiation) under real-sky conditions and the validation of proposed estimation models by analyzing the most important statistical indicators. Two types of regressions are proposed for the estimation of solar daily global irradiation; the first type is based on the second order degree Ångström-Prescott correlations; the second type uses the second order Ångström-Prescott correlations only for days with sunshine fraction values higher than 0.1; for days with sunshine fraction values less than 0.1, there are developed regressions depending on sunshine fraction, air temperature and amount of precipitable water. Based on the two types of models for estimating daily global irradiation, regressions to estimate the daily diffuse irradiation will also be determined. The particularization of regression coefficients is performed for basin urban area of Braşov (Romania). The proposal of some correlations having as input data, the air temperature and the amount of precipitable water was based on the following reasons: solar radiation is the main climatic factor that causes changes in other climatic parameters and the multitude of radiative factors, dynamic factors, physical-geographical factors and even those economical-geographical contribute to the individualization of Braşov urban area, giving this, its own characteristics. Finally, the statistical analysis is developed and the performances comparison of estimation models is achieved.