Theoretical and experimental study on selection of physical dimensions of passive solar greenhouses for enhanced energy performance

Space formation of passive solar greenhouses plays a dominant role in the creation of required lighing and thermal conditions and in increasing the efficiency of solar energy utilisation. In this study, the energy balance equation analysis was implemented in EnergyPlus software to numerically model the thermal performance of a passive solar greenhouse, located in the Beijing Region. Comparison of numerical and experimental data indicated a high prediction accuracy of the numerical model, which then was used to conduct a parametric analysis of the effect of main physical dimensions on the energy performance of such greenhouses. As a result, a range of rational values of physical dimensions was proposed for this type of greenhouses. The originality of the research approach is using parametric analysis data, obtained from the calibrated numerical model of greenhouses, to derive novel analytical correlations for rapid calculation of the main physical dimensions of passive solar greenhouses. The correctness of the proposed novel analytical method for calculation of main physical dimensions of passive solar greenhouses was experimentally confirmed in a series of comparative physical tests on various greenhouse models. The advantage of the proposed analytical correlations is that these are valid for a wide range of geographical latitudes in China and other regions, where a similar type of greenhouses can be exploited.