Design of heating and cooling system for offices in bussiness and services building

Cilj ovog rada je bio izraditi projekt sustava grijanja, hlađenja i ventilacije poslovno-servisne zgrade smještene u gradu Zagrebu. Temelj cjelokupnih proračuna su toplinski gubitci i toplinsko opterećenje zgrade, dobiveni prema normama HRN EN 12831 i VDI 2078, prema kojima je dimenzionirana potrebna oprema. Temeljem norme HRN EN 13790 je određena godišnje potrebna energija za grijanje i hlađenje zgrade te u kombinaciji sa normama HRN EN 15316 i HRN EN 15243, električna energija i energija koju je gorivom potrebno isporučiti GViK sustavu s ciljem postizanja traženih parametara toplinske ugodnosti u zgradi. Kako bi se osiguralo da GViK sustav ima najbolji mogući odnos pogonskih prema investicijskim troškovima, provedena je tehnoekonomska analiza 3 varijante sustava. Naglasak je stavljen na alternativne izvore energije i visokoučinkovite sustave. U prvoj varijanti je razmatran cjelogodišnji rad kotla na pelete za grijanje prostora i pripremu PTV te VRV sustava hlađenja. Druga varijatna je obuhvatila plinski kondenzacijski kotao u kombinaciji sa rashladnikom vode sa zrakom hlađenim kondenzatorom. Treća varijanta rješenja je bila geotermalna dizalica topline podzemna voda / voda kao centralnog sustava za grijanje i hlađenje. Provedenom tehnoekonomskom analizom odabrana je druga varijanta sustava jer se pokazalo da ima najniže investicijske troškove dok se pogonski troškovi ne razlikuju značajno od pogonskih troškova ostala dva sustava.The purpose of this thesis was to design a system for heating, refrigeration and ventilation for a business and service building located in the city of Zagreb. Basis for all the calculations made in the thesis were the buildings heat loss and cooling load which were calculated according to standards HRN EN 12831 and VDI 2078, by which all the necessary system components were selected. The required yearly thermal energy for heating and cooling was calculated according to HRN EN 13790. Those values in combination with standards HRN EN 15316 and HRN EN 15243 resulted in required electrical energy and fuel as input in the buildings HVAC system with the goal of achieving the desired parameters of thermal comfort for all the occupants. As to ensure that the HVAC system has the optimal ratio of operating to investment costs a technical and economic analysis of 3 different systems were conducted. Alternative energy sources and high-efficiency systems are highlighted here. In the first proposed system a pellet boiler for heating and domestic hot water production in combination with VRV cooling system were considered. The second system consists of a condensing gas boiler and a water chiller with an air cooled condenser. The third proposed system solution was a geothermal heat pump which uses underground water as a heat source / sink as a central apparatus for heating and cooling. The chosen system was the second one because it had the lowest investment costs among the three systems with operating costs that do not differ much from the other systems