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Demand for domestic hot water and heating is rarely perfectly concurrent with solar irradiation, which means that collectors can overheat in periods of high incident radiation and low demand. Phase change materials have been used as energy storage in space heating applications to absorbs excess heat during low demand periods for use in peak demand periods. This paper reviews the current state of research on the possibility of application of such materials as energy storage for solar collectors, in order to avoid collector overheating. Finally, various materials were evaluated and ranked for this application based on required properties and price. An example model of such materials being applied in a typical family house domestic hot water solar system is also provided.

When using infrared thermography in agriculture, the Crop Water Stress Index needs to be calculated. This requires the canopy temperature, as well as the dry and wet reference temperature, to be determined. In this paper, an overview of possible methods for their calculation and/or measurement is given, and an analysis which compares CWSI values obtained using different methods of determining the canopy temperatures, as well as different dry and wet reference temperatures, is presented. The effect of different methods on the statistical significance of the correlations found are presented and analyzed to determine the most promising method.

This paper deals with the possibility of using infrared thermography to determine the irrigation requirement for a given field depending on the water stress level of the plants. The experiments were performed on vines at the site in the village of Jadrtovac near Šibenik, Croatia. The water stress level of plants was determined through leaf temperature measurements and measurements of leaf water potential (LWP). Leaf temperature measurements were performed using infrared thermography. Based on these measurements the relationship between the LWP and a derived factor, Crop Water Stress Index (CWSI) was investigated.The results obtained show that infrared thermography could be successfully used to measure the leaf temperature, which is the input parameter for calculating the CWSI.