Evolution of all-glass nearly Zero Energy Buildings with respect to the local climate and free-cooling techniques

Abstract

This paper presents research on the nearly Zero Energy Buildings (nZEB) metrics of an all-glass office building with advanced multi-layer six-pane glass and building integrated photovoltaic (BIPV) façade structures in different climate conditions. The study was carried out in the following steps: i) development of a time series model of dynamic thermal response of multi-layer 6-pane glass and BIPV façade structures on the basis of transient computational fluid dynamics simulations, ii) integration of the façade structure dynamic model into the building dynamic model by adapting TRNSYS software code, iii) determination of the final energy balance including heating, cooling, ventilation, lighting, and on-site electricity production, iv) nZEB metrics evaluation considering night-time cooling by ventilation, evaporation cooling and hybrid ventilation of case study office buildings. It is shown that energy need for the cooling of the studied office building is dominant in all considered climate conditions, although it can be decreased up to 23% in most favourable considered climate conditions by implementing free cooling techniques. The case study buildings with BIPV structures on their east and west façades meet more stringed nZEB criteria; in addition, final energy demand decreases by 17-37% in comparison to the reference all-glass building. In the case of all-BIPV buildings, the final energy demand is decreased by 36-48%. Such buildings can significantly contribute to the mitigation of global climate change, as BIPV electricity production exceeds the building's energy demand.Keywords: nearly Zero Energy Buildings, multi-layer glass structures, building integrated photovoltaics, computational fluid dynamics, dynamic building thermal response model, natural space cooling Recently, research has focused on advance multi-layer, vacuum, and aerogel glass façade structures [10-13] with highly reduced U-values for nZEB buildings. However, Murano et al. [14] demonstrated that, with increased window-to-wall ratios, space cooling is the most significant challenge for nZEB in southern European climate conditions. The same conclusions can be derived from the study presented by Bruno, [15]; results also showed that in all-glass buildings yearly energy need is the lowest with glazing with the lowest thermal and total solar energy transmittance. In these studies, static numerical models for glazing prevail, leading to a single thermal transmittance value of glazed façade structures and non-transient heat transfer conditions. Lu and Memari [16] published a study on the evaluation of the thermal transmittance of building envelopes, comparing hot-box laboratory methods for the determination of steady-state thermal transmittance. In their study, they show the importance of using dynamic models in case of in-situ measurement conditions for the accuracy of results. Nevertheless, Foucquier et al. [17] and Li and Wen [18] point out that the transient numerical modelling of the thermal response of the buildings requires the transient mode...

Primary Seal Deformation in Multipane Glazing Units

“…Multipane glazing units are attractive due to high energy efficiency of those buildings where they are built-in [9]. However, in multipane glazing arrangements (i.e., in glazing with more than three glass panes) a further restriction stems from the maximum permitted operating temperature of the PIB primary sealant.…”

Evaluation of Energy and Daylight Performance of Old Office Buildings in South Korea with Curtain Walls Remodeled Using Polymer Dispersed Liquid Crystal (PDLC) Films

“…Most activities are focused on improving insulation performance, for which frames using low-emissivity glass, argon gas, triple glass, and thermal bridging insulation materials are mainly applied. However, to implement zero-energy buildings [4,5], solar radiation control is crucial as well as insulation performance. Particularly in South Korea, where the winter and summer weather are clearly distinguished, the solar radiation inflow and blocking control of building envelopes can have a significant effect in terms of energy efficiency [6].…”

Fast Modelling of nZEB Metrics of Office Buildings Built with Advanced Glass and BIPV Facade Structures

“…Table 1 shows the thermal and radiative properties of the product range. Other thermal and radiative properties are presented in [35,[37][38][39]. By replacing the outer glass pane with glass BIPV modules, a BIPV facade structure can be made.…”

“…BIPV facade structures can be transparent or opaque [29][30][31], built with a-Si, p-Si, or m-Si silicon PV cells with or without a ventilation cavity [32,33] or even as colored dye-sensitized solar cells (DSC), to ensure architectural diversity [34]. In the case of integration in glazed facade, BIPV significantly influences heating, cooling, and lighting energy demand [35]. Besides that, pre-defined tilt and orientation of facade integrated BIPV, as well as shading by surrounding objects and enlarged reflective solar irradiation, have a significant influence on electricity production [36].…”

“…Besides that, pre-defined tilt and orientation of facade integrated BIPV, as well as shading by surrounding objects and enlarged reflective solar irradiation, have a significant influence on electricity production [36]. In this paper, the developed fast modelling tool for the evaluation of nZEB metrics of office buildings built with advanced glass and advanced building integrated photovoltaic facade structures [35,37,38] is shown. The paper shows (i) how the energy performance of buildings (EPB) labelling tool, following the EPBD requirements, was upgraded to generate a set of simulation results of monthly values of building energy efficiency indicators using a Taguchi matrix, (ii) how the evaluation tool for the determination of nZEB criteria based on multi-parametric regression models was developed and combined with the EPB tool, and (iii) case studies of fast modelling of energy efficiency performance of office buildings.…”