The paper presents a theoretical analysis of thermal energy storage filled with phase change material (PCM) that is aimed at optimization of an adsorption chiller performance in an air-conditioning system. The equations describing a lumped parameter model were used to analyze internal heat transfer in the cooling installation. Those equations result from the energy balances of the chiller, PCM thermal storage unit and heat load. The influence of the control of the heat transfer fluid flow rate and heat capacity of the system components on the whole system operation was investigated. The model was used to validate the selection of Rubitherm RT62HC as a PCM for thermal storage. It also allowed us to assess the temperature levels that are likely to appear during the operation of the system before it will be constructed.

For the Gdansk Library, participation in the Nights of Museums is an effective way of execution of its didactic and science-promoting goals defined in its mission. The interesting main themes, presentation of the library’s rich collections, as well as the involvement of the organisers and the participating staff members all translated into the success of the nine editions of the event between 2011 and 2019. Their subsequent main themes were: A night with Johannes Hevelius from the treasury of the Gdansk Library, Fashion for books – fashion in books, Horror in the library, The world of the library on one night, Taking a book to further than the horizon, The Library as a Garden, Gedanum domus nostra – Our home – Gdansk, In mari vita tua – In the sea is your life, Genius – on the 500th death anniversary of Leonardo da Vinci. During the past Night of Museums, visitors to the Library were most impressed by the displays in the Reading Room of Historical Collections. Such presentations are sometimes the only opportunity to have a close contact with valuable manuscripts, old printed books, prints, and other special collections, and to hear competent staff members talking about them. Regular attractions of the Night of Museums included displays referring to the theme of the event in the exhibition room and a sale of library publications in the hall of the historical building at ul. Wałowa 15. The subsequent organisers of the project, also in cooperation with other cultural institutions from the Tri-City, each time enriched the programme with fascinating talks, thematic workshops, and even concerts. During the subsequent editions of the Night of Museums, the Gdansk Library hosted an average of 670 visitors, which testifies to the value of this tool of promotion of the library.