Ciril Arkar

Ciril Arkar


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2020 in Energies
Verified
Journal Article
Open access
PDF file
SDSuzana Domjan
Suzana Domjan
LPLenart Petek
Lenart Petek
CACiril Arkar
Ciril Arkar
SMSašo Medved
Sašo Medved
Building integrated photovoltaics (BIPV) is technology that can significantly increase the share of renewable energy in final energy supply and are one of essential technologies for the nearly zero-energy buildings (nZEB), new build and refurbished. In the article (a) an experimental semitransparent BIPV glazed façade structure with 60% of PV cell coverage is shown; (b) energy efficiency indicators were developed based on identified impact parameters using experimental data; and (c) multi-parametric models of electricity generation, preheating of air for space ventilation, and dynamic thermal insulation features that enable prediction of solar energy utilization in different climate conditions are shown. The modeled efficiency of electricity production of BIPV was in the range between 8% and 9.5% at daily solar radiation above 1500 Wh/day, while low impact of outdoor air temperature and ventilation air flow rate on PV cell cooling was noticed. Between 35% and 75% of daily solar radiation can be utilized by preheating the air for space ventilation, and 4.5% to 7.5% of daily solar radiation can be utilized in the form of heat gains through opaque envelope walls.

20 August 2019 in Energies
Verified
Journal Article
Open access
PDF file
SDSuzana Domjan
Suzana Domjan
SMSašo Medved
Sašo Medved
BČBoštjan Černe
Boštjan Černe
CACiril Arkar
Ciril Arkar
The planning process of nearly Zero Energy Buildings (nZEB), as defined in Energy Performance of Buildings Directive (EPBD), requires that designers check their solutions at all stages of planning. In the initial design phase, methods and tools for which only basic design knowledge of the modelling of energy efficiency indicators is required are often sufficient. With the introduction of fast modelling techniques, designers’ work can be simplified. A method and software for the fast modelling of nZEB energy efficiency indicators of buildings constructed with advanced multi-layer glass and building integrated photovoltaics facade (BIPV) structures are presented. The computer tool for fast modelling combines (i) upgraded national certificated software for energy performance of buildings (EPB) evaluation, which is used for performing auto-repeating numerical calculations based on the design of experiments (DOE) and (ii) software for the determination of multiple linear regression models and the presentation of results. The case studies made for different buildings and climate conditions show the variety of options offered by the developed fast modelling approach. It can be seen that buildings with a large proportion of advanced glassed facade and even all-glass buildings can fulfil nZEB requirements via the on-site production of electricity with BIPV facade structures.

1 August 2019 in IOP Conference Series: Earth and Environmental Science
Verified
Conference Paper
Open access
PDF file
CACiril Arkar
Ciril Arkar
SDS Domjan
S Domjan
DMD Majkovič
D Majkovič
JŠJ Šumi
J Šumi
SMS Medved
S Medved
The paper presents a study on the thermal and hydrological response of lightweight extensive green roofs with lightweight mineral wool growing media in different European climate conditions. The green roof heat and mass transfer model was developed and experimentally validated. It was then integrated into a developed software tool for the whole year analysis of the green roof thermal and hydrological performance. The results of performed numerical analysis showed that heat losses in heating season and heat gains in summer months of the green roof is smaller compared to the reference non-vegetated roof in all considered climate conditions and depends on thickness of lightweight mineral wool growing media and especially on the green roof’s irrigation scenario. The results of numerical analyses also demonstrated that the water retention of green roofs can be considerably improved if irrigation scenario considers the weather forecast. The weather forecast based green roofs´ irrigation also improves retention at stormwater events.

1 August 2019 in IOP Conference Series: Earth and Environmental Science
Verified
Conference Paper
Open access
PDF file
CACiril Arkar
Ciril Arkar
SDS Domjan
S Domjan
DMD Majkovič
D Majkovič
JŠJ Šumi
J Šumi
SMS Medved
S Medved
Due to energy, environmental, and social benefits, green roofs are recognized as a bioclimatic technology and sustainable construction systems and are becoming a predominant solution in connection with urban planning and building envelope retrofitting. To support design and marketing of Urbanscape® lightweight extensive green roofs a special software tool was developed, which is presented in the paper. Performance evaluation tool (PET tool) is validated based on extensive and continuous 5-years in-situ monitoring of thermal and hydrological response of different Urbanscape green roofs. The key performance indicators of Urbanscape green roofs are evaluated based on calculated thermal and hydrological response. To emphasize the advantages of green roofs thermal response and performance indicators are determined also for non-vegetated roof for the same boundary conditions. PET tool enables i) evaluation of Urbanscape green roofs’ whole year thermal and hydrological response, ii) to search for the optimal design of the Urbanscape green roof system in terms of energy and water performance, iii) evaluation of comparative advantages compared to non-vegetated roof, iv) energy savings and CO2 emission reduction analyses for heating and cooling season. Analyses can be made for arbitrary worldwide climate conditions since meteorological parameters are gathered from Meteonorm database.