Analiza vplivov zelenih streh na toplotni odziv večstanovanjske stavbe v Ljubljani

Jurko, Luka (author), Košir, Mitja (mentor)

V magistrski nalogi smo obravnavali učinek ozelenjenih konstrukcijskih sklopov na toplotni odziv in energijsko učinkovitost objekta. Določiti smo želeli, kakšen bi bil učinek namestitve zelene strehe na večstanovanjski objekt v Ljubljani v okviru energetske prenove, kako bi različne izvedbe zelenih streh v kombinaciji s klasično toplotno izolacijo delovale na energijske potrebe objekta. Zato smo v programu Design Builder izdelali model večstanovanjske stavbe vključno s karakteristikami in urniki vgrajenih sistemov, pohištva in materialov, uporabnikov in lokacije. Želeli smo ustvariti model, ki bi lahko natančno določil energijske potrebe objekta. V modelu smo nato definirali šestnajst različnih stavbnih ovojev; poleg neozelenjenega in neizoliranega stavbnega ovoja smo kombinirali tri različne ozelenitve in tri različne debeline toplotne izolacije. Za sicer identične objekte z različnimi stavbnimi ovoji smo nato določili energijske potrebe za ogrevanje in hlajenje stavbe tako na letni ravni kot za posamezne vroče in hladne dele leta, za vsako etažo posebej in stavbo v celoti. Magistrska naloga obsega definicije stavbe in ozelenitev, analize energijskih potreb pri različnih stavbnih ovojih, oceno učinkovitosti ozelenitev, klasične toplotne izolacije in kombinacij obeh ter analizo delovanja različnih variant stavbnega ovoja s poudarkom na načinu delovanja ozelenitve. Rezultati so pokazali, da je ozelenjena streha kot ukrep za zmanjšanje rabe energije za ogrevanje in hlajenje najučinkovitejša pri neizolirani strehi. Učinkovitost ozelenjene strehe kot ukrepa za izboljšanje energijske učinkovitosti pa se zmanjšuje z povečevanjem debeline konvencionalne toplotne izolacije. Najučinkovitejša varianta je rabo energije zmanjšala za 52,16 % v primerjavi z izhodiščno varianto, brez toplotne izolacije in ozelenitve. Učinek ozelenitve je znašal do 20 % za neizolirane stavbe in do 1,5 % pri toplotno izolirani stavbi z ozelenjeno streho.

• Language: Slovenian
• Keywords: zelene strehe, energetska prenova, ozelenjeni konstrukcijski sklopi, raba energije
• Work type: Master's thesis/paper
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Year: 2024
• PID: 20.500.12556/RUL-161671
• Publication date in RUL: 13.09.2024

Secondary language

• Language: English
• Title: Analysis of the effects of green roofs on the thermal response of a multi-apartment building in Ljubljana

Abstract

In this master’s thesis I explore the effects of green roof systems on a building’s energy efficiency and thermal response. I wanted to determine the effect of installing a green roof on a multi-storey apartment building in Ljubljana as part of an energy efficiency renovation, to determine the effect of different variations of green roof and thermal insulation on the building’s energy needs. To that end I created a model of the building using the Design Builder software, complete with characteristics and schedules of the systems, materials, furniture, users and the building’s location. I wanted the model to be able to produce an accurate estimation of the building’s energy needs. Within that model I then defined sixteen different combinations of the building’s envelope; I combined a bare envelope, without green roof systems or thermal insulation with three different green roofs and thermal insulation in three different thicknesses. I ran an analysis of energy needs for the otherwise identical building models with different envelopes, determining the energy needs for heating and cooling for each individual envelope variation for the whole year, and separately for hot and cold parts of the year, for the entire building as well as for individual storeys. The thesis includes the definitions of the building and greenery systems, analyses of energy needs for each envelope variant, a discussion on the effects of different green roof variants, thermal insulation and the combination of both on a building’s energy needs. The results have shown, that the use of a green roof as an energy-reducing measure is most effective in the non-insulated variants of the building envelope. The effectiveness of the green roof as a measure to reduce energy needs decreases with increasing thickness of conventional thermal insulation. The most effective variant reduced energy needs for heating and cooling by as much as 52,16 %, with the effects of the greenery itself ranging from 20 % for buildings without thermal insulation to about 1,5 % for buildings with green roofs and thermal insulation.

• Keywords: green roof, energy efficiency renovation, green building envelope, energy needs