Optimizacija ovojnice zgrade korištenjem dinamičkih simulacija

undergraduate thesis

• Title (english): The optimisation of building envelope using dynamic simulations
• Author: Alojzije Sokolić Frigula
• Mentor: Tea Žakula (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2021-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Process Energy Engineering

Abstract

U ovome je radu opisan postupak i prikazani su rezultati optimizacije vanjske ovojnice zgrade javne namjene u Hrvatskoj Kostajnici. Zgrada je trenutačno energetski vrlo neučinkovita te je s ciljem povećanja energetske učinkovitosti i približavanja konceptu zgrade gotovo nulte energije izrađen energijski model u računalnom programu TRNSYS. Energijskim su modelom izračunate godišnje satne vrijednosti te godišnja potrebna energija za grijanje i hlađenje. Postojeće stanje zgrade poslužilo je kao referentna točka od koje je započeo proces optimizacije vanjske ovojnice. Za potrebe ovog rada, kao sustav proizvodnje toplinske i rashladne energije pretpostavljena je dizalica topline zrak-voda. Korištenjem faktora grijanja i hlađenja dizalice topline te cijene električne energije precizno su izračunati pogonski troškovi. Prvi korak optimizacije analizirao je zamjenu dotrajalih, postojećih prozora s novim prozorima s dva ili tri stakla, čime se postigla značajna ušteda energije. Sljedeći je korak bio, uz nove prozore, postavljanje toplinske izolacije na vanjske zidove zgrade. U usporedbi s početnim stanjem, toplinska izolacija i novi prozori omogućuju ukupnu godišnju uštedu energije za grijanje od 78,3%, no istovremeno uzrokuju povećanje potrebne energije za hlađenje za 42,1% zbog svojstva toplisnke izolacije da zadržava toplinu unutar prostorija. U posljednjem je koraku modeliran sustav zasjenjenja čime se pokazalo da takav sustav značajno utječe na potrošnju energije i može pridonijeti u daljnjim uštedama. Sustav zasjenjenja najviše je utjecao na smanjenje potrebne energije za hlađenje, tako da je u konačnici kombinacija toplinske izolacije i novih prozora sa zasjenjenjem rezultirala smanjenjem ukupne potrebne energije u iznosu od 63%, odnosno smanjenjem godišnje isporučene električne energije u iznosu od 65,8%, što znači da su pogonski troškovi smanjeni za 60,6%. Period povrata investicije iznosi 139 godina.

Abstract (english)

This paper describes the procedure and results of the building envelope optimization of a public building in Hrvatska Kostajnica. The building is very energy inefficient in its current condition. In order to make it energy efficient and closer to the concept of the nearly-zero energy building (nZEB), an energy model of the building has been created using the computer program TRNSYS®. The energy model was used to calculate hourly and annual heating and cooling energy needs. The existing condition of the envelope and current energy needs were a baseline for the optimization. An air-to-water heat pump was assumed to be the production system for heating and cooling energy. Heat pump coefficients of performance and the price/tariff of electricity were used to calculate annual operating expenses of the building. The first step in the optimization of the building envelope was to replace old, inefficient windows with new, double-paned or triple-paned insulated windows. This proved to be very energy efficient, resulting in substantial energy savings and savings in operating costs. The next step was to add thermal insulation on external walls in addition to the new windows. The combination of thermal insulation and new windows have resulted in even greater energy savings and the reduction in operating costs. Compared to the baseline, the annual heating need was reduced by 78,3%. However, the annual cooling need increased by 42,1% because the thermal insulation effects prevented the heat from escaping the building. As the last step, a shading system has been implemented, which also affected the energy needs. Specifically, it has significantly reduced the annual cooling needs. In conclusion, the total energy need for the building was reduced by 63% and the delivered (electrical) energy was reduced by 65,8%. Furthermore, the annual operating expenses were reduced by 60,6% and the return of investment equals to 139 years.

• Keywords: optimizacija ovojnice; energijski model; nZEB; TRNSYS; energetska obnova
• Keywords (english): envelope optimization; energy model; nZEB; TRNSYS; energy renovation
• Language: croatian
• URN:NBN: urn:nbn:hr:235:026091
• Study programme: Title: Mechanical Engineering; specializations in: Design, Process and Energy Engineering, Production Engineering, Engineering Modelling and Computer Simulation, Marine Engineering, Industrial Engineering and Management, Materials Engineering; Course: Process and Energy Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-09-22 19:53:21