HVAC system for a nearly zero energy building

Cilj ovog rada odnosno projekta jest bio odrediti najoptimalniji sustav grijanja, hlađenja i pripreme potrošne tople vode sve s ciljem da objekt ima gotovo ili u potpunosti nultu potrošnju energije. Za postizanje istog izradio se sustav grijanja i hlađenja koji uključuje dizalicu topline, ventilokonvektore i podno grijanja uz sustav mehaničke ventilacije dok je za pripremu potrošne tople vode korišten sustav koji objedinjuje ili dizalicu topline samu u sustavu ili istu ukomponiranu u sustav s solarnim kolektorima. Da bi se nadoknadila potrošnja električne energije s vlastitom proizvodnjom iste koristio se fotonaponski sustav. Čitav projekt je izrađen u Trnsys-ovom programu Simulation Studiu u kojem su kompletno provedene simulacije navedenih sustava. Također za potrebe izrade 3D modela samog objekta korišten je program SketchUp. Analizom proizvedenih energija za potrebe grijanja i hlađenja te usputno s time i potrošnjom električne energije za postizanje istog odnosno za osiguravanje rada sustava te usporedbom istih s proizvedenom električnom energijom uspjelo se ostvariti da je zgrada energetski neovisna o vanjskoj mreži. Međutim također se pokazalo da bi zgrada postala energetski neovisna potrebni su puno viši investicijski troškovi samih sustava što daje da je isplativije financijski gledano koristiti sustave koji nemaju ugrađene solarne i fotonaponske sustave.The aim of this work or project was to determine the most optimal system of heating, cooling and preparation of domestic hot water, all with the aim that the facility has almost or completely zero energy consumption. To achieve the same, a heating and cooling system was created that includes a heat pump, fan convectors and underfloor heating with a mechanical ventilation system, while for the preparation of hot water a system was used that combines either the heat pump alone in the system or the same one integrated into the system with solar collectors. In order to compensate the consumption of electricity with its own production, a photovoltaic system was used. The entire project was created in the Trnsys program Simulation Studio, in which the simulations of the mentioned systems were completely carried out. The SketchUp program was also used to create a 3D model of the object itself. By analyzing the energy produced for heating and cooling purposes and, incidentally, the consumption of electricity to achieve the same, i.e. to ensure the operation of the system, and by comparing it with the electricity produced, it was possible to realize that the building is energetically independent of the external network. However, it also turned out that in order for the building to become energy independent, much higher investment costs of the systems themselves are required, which means that it is financially more profitable to use systems that do not have installed solar and photovoltaic systems