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Zaradi rasti populacije na Zemlji, boljšega ugodja in standarda življenja ljudi raba energije raste. Ker je v veliko procesih toplota stranski produkt, bi bilo smiselno to toploto čim bolj učinkovito uporabiti. Zaradi relativno velike gostote energije in naraščajoče pozornosti, ki jih tej hranilniki prejemajo smo se odločili izdelati latentni hranilnik toplote. Z grelci smo segreli medij, vodo, ki smo jo dovedli v hranilnik. Nato smo po polnjenju hranilnik praznili z uporabo hladne vode ter pomerili shranjeno toploto. V hranilniku toplote, ki namesto vode vsebuje FSS, je količina shranjene toplote na volumen okoli šestkrat večja. Veliko gostoto energije bi se lahko uporabilo za regulacijo temperature ali pa shranjevanje odvečne toplote. Due to the growth of the population on Earth, better comfort, and the standard of living of people, the use of energy is increasing. Since heat is a by-product in many processes, it would make sense to use this heat as efficiently as possible. Due to the relatively high energy density and the increasing attention that these storage devices are receiving we decided to make a latent heat storage device. We used heaters to heat the medium - the water - which we fed into the reservoir. Then, after filling, the storage tank was emptied using cold water, and the stored heat was measured. In a heat storage tank that contains PCM instead of water, the amount of stored heat per volume is about six times greater. The high energy density could be used to regulate temperature or store excess heat.

A key component in the conversion process of concentrated solar power (CSP) into thermal energy is a solar absorber coating. Many experimental and simulated coatings for various substrates for CSP water/steam or molten salt absorbers have been developed. The main challenges today remain in the selection of a low-cost and effective fabrication method, appropriate for industrial production, and assessment of the degradation rate and service life of these coatings, which affect the efficiency of the plant and the LCOE. In this article, we review different types of mid- (100 < T < 400 ◦C) and high-temperature (>400 ◦C) absorber coatings and their fabrication methods. The emphasis is on the solar absorptance, thermal emittance and the long-term (>10 years) thermal stability of the coatings. Spectral selectivity of the coatings, which is more difficult and expensive than other means, was proven to be essential for a low-to-mid temperature range and low concentration ratios, yet for high temperatures and high concentration ratios, high solar absorptive coatings can achieve the same or even better performance than spectral selective ones. Important factors for an efficient CSP absorber are compatibility of the coating and substrate under cyclic temperature conditions and high heat transfer rate to a heat transfer medium.

Microporous triclinic AlPO4-34, known as APO-Tric, serves as an excellent water adsorbent in thermal energy storage, especially for low temperature thermochemical energy storage. Increased water adsorption capacity of thermochemical material usually leads to higher thermal energy storage capacity, thus offering improved performance of the adsorbent. The main disadvantage of aluminophosphate-based TCM materials is their high cost due to the use of expensive organic templates acting as structure directing agents. Using ionic liquids as low cost solvents with associated structure directing role can increase the availability of these water adsorbents for TES applications. Here, a green synthesis of APO-Tric crystals at elevated and ambient pressure by using 1-ethyl-3-methyl imidazolium bromide ionic liquid is presented. Large 200 µm romboid shaped monocrystals were obtained at 200 °C after 6 days. The structure of APO-Tric and the presence of 1,3-dimetylimidazolium cation in the micropores were determined by single crystal XRD at room temperature and 150 K. Water sorption capacity of APO-Tric prepared by ionothermal synthesis at elevated pressure increased in comparison to the material obtained at hydrothermal synthesis most probably due to additional structural defects obtained after calcination. The reuse of exhausted ionic liquid was also confirmed, which adds to the reduction of toxicity and cost production of the aluminophosphate synthesis.

The main goal of this research was to develop the adsorption thermal storage device for domestic heating system charged by solar collectors and to indicate a new way of storing energy. Main characteristic of the storage system is to retain the energy for a longer period (seasonal storage), as long as the adsorbent and adsorbat are separated. In this research the influence of several parameters on the adsorption heat storage system is performed such as: the quantity of the stored heat, the inlet and the outlet water temperatures, the water mass flow and the saturation of the adsorbent. Adsorbent silica gel HX-13 (sodium aluminosilicate Na2O Al2O3 * 2SiO2) in the form of granule was used. According to the results the conclusion can be made that the low adsorption heat storage is a consequence of low hydrophilic characteristic of the used adsorbent and therefore additional research is needed.