Comparison of solar district heating system operation in Denmark and Croatia

Put prema čistoj energiji u svijetu i Europi vodi na prelazak s tradicionalnih izvora energije na obnovljive izvore energije. U Europi u sektoru zgradarstva troši se oko 40% finalne energije i emitira 36% stakleničkih plinova. Za grijanje zgrada i pripremu potrošne tople vode kao najbolje rješenje pokazuje se centralizirani toplinski sustav te je cilj u takve sustave implementirati obnovljive izvore energije. U ovom radu napravljena je analiza centraliziranog solarnog toplinskog sustava u Danskoj te kao primjer takovog sustava detaljna analiza rada centraliziranog solarnog toplinskog sustava u gradu Gramu. Pokazano je kako je moguće skladištiti Sunčevu energiju preko ljeta i koristi je zimi uz pomoć solarnih kolektora, sezonskog toplinskog spremnika i dizalice topline. Drugi dio rada temelji se na implementaciji takovog sustava u gradu Zaprešiću. Prvo je napravljena analiza postojećeg stanja, a zatim tehno-ekonomska analiza budućeg centraliziranog solarnog toplinskog sustava pomoću alata F-easy i Sunstore 4 Feasibility Evaluation alata. Napravljena je analiza za 2 moguća scenarija i odabran je sustav koji uključuje polje solarnih kolektora, sezonski spremnik topline, kotao na biomasu i dizalicu topline. Na kraju je pokazan utjecaj promjene investicijskih troškova i cijene toplinske energije na isplativost ovakvog projekta.On the way to clean energy in the world and Europe, we have to switch from traditional energy sources to renewable ones. Building sector is the largest energy consumers, accounting for 40% of final energy consumption and 36% of greenhouse gas emissions in Europe. A centralized heating system is proving to be the best solution for heating and hot water preparation, and the goal is to implement renewable energy sources in such systems In the proposed thesis, an analysis of the solar district heating system in Denmark is made, and as an example of such a system, a detailed analysis of the operation of the centralized solar district heating system in the city of Gram. It has been shown that it is possible to store solar energy over the summer and use it in the winter with the help of solar collectors, a seasonal heat storage tank and a heat pump. The second part of the thesis is about the implementation of such a system in Zaprešić. First, an analysis of the current situation was made, followed by a techno-economic analysis of the future centralized solar district heating system using the F-easy tool and the Sunstore 4 Feasibility Evaluation Tool. A comparison of the two scenarios was conducted, and the second scenario was selected as optimal, which includes a solar collector field, a seasonal heat storage, biomass boiler, and a heat pump. Finally, the impact of changes in investment costs and heat prices on the profitability of such a project is show