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Calibration rational and annual 2016 data of the ICTA building energy consumption and temperatures

Calibration rational and annual 2016 data of the ICTA building energy consumption and temperatures

Contexts in source publication

Context 1
... actual data is used to calibrate EnergyPlus model in order to produce later both energy and environmental results of the ICTA building with no iRTG and with the roof structure composition achieving a statutory U-Value of 0.41 W/m 2 K according to the roof insulative requirements defined by the Spanish Technical Building Code for the Barcelona region CTE-DB-HE (Standard 2006). In order to fulfil these requirements, monthly energy consumption data is calibrated (see Figure 1) and used to evaluate the model energy prediction accuracy. These results shall satisfy ASHRAE Guideline 14-201414- (Guideline 2014). ...
Context 2
... this can be understood as recovered energy flows from the building which would be lost without the iRTG insulation effect (see Figure 9), so extra 43.78 MWh could be needed annually. 2. From the greenhouse to the building: Figure 10 demonstrates calibrated model simulation results for ICTA building with and without an iRTG (using 2015 site-specific weather files). Note that both heating and cooling demands are administered across the year as has been the case in the real building in order to avoid excessive temperature swings due to the critical nature of lab and iRTG operations. ...
Context 3
... actual data is used to calibrate EnergyPlus model in order to produce later both energy and environmental results of the ICTA building with no iRTG and with the roof structure composition achieving a statutory U-Value of 0.41 W/m 2 K according to the roof insulative requirements defined by the Spanish Technical Building Code for the Barcelona region CTE-DB-HE (Standard 2006). In order to fulfil these requirements, monthly energy consumption data is calibrated (see Figure 1) and used to evaluate the model energy prediction accuracy. These results shall satisfy ASHRAE Guideline 14-201414- (Guideline 2014). ...
Context 4
... this can be understood as recovered energy flows from the building which would be lost without the iRTG insulation effect (see Figure 9), so extra 43.78 MWh could be needed annually. 2. From the greenhouse to the building: Figure 10 demonstrates calibrated model simulation results for ICTA building with and without an iRTG (using 2015 site-specific weather files). Note that both heating and cooling demands are administered across the year as has been the case in the real building in order to avoid excessive temperature swings due to the critical nature of lab and iRTG operations. ...

Citations

... These differences are smaller compared to the analysis m -2 of greenhouse due to fertilizer-associated SOD impacts. Without accounting for the crop and energy multifunctionality of rooftop farming in the ICTA-UAB building (Muñoz-Liesa et al., 2021b, 2020a, the obtained results kg -1 of tomato are similar to those achieved in unheated greenhouses. Still, the iRTG operating with a passive ventilation configuration requires minimum electricity duties (representing 6% of the total passive energy gains) and thus, largely benefits from building waste heat. ...
Article
It is widely accepted that urban agriculture provides multiple benefits to society. Rooftop greenhouses are a form of urban agriculture that takes advantage of urban resources (urban land, sunlight spaces) and waste flows (energy, nutrients) to provide food and other ecosystem services to cities. However, the integration of urban greenhouses within buildings is a complex issue that must be addressed in-depth. Compared to the well-known conventional greenhouses, the urban environment requires an assessment to later optimize greenhouse structures and covering materials. The aim of our study was to environmentally assess rooftop greenhouses and propose improving scenarios. Life cycle assessment was used to detect environmental hotspots and to evaluate different impact categories of an iRTG case study in the Barcelona area. Results showed that the greenhouse environment and ventilation design directly determine greenhouse structures and environmental impacts. Optimized strategies showed a potential reduction of up to 35% of the amount of structural steel used, while less improvement potential existed for covering materials (5%). Compared to conventional greenhouses, 1.6 times more steel and up to 8 times more energy were required to build the urban greenhouse in this study. The assessment revealed that these differences can be reduced by optimizing greenhouse structures to avoid a shift of material flows and environmental impacts from building urban greenhouses compared to conventional greenhouses. In turn, the assessment presented here provides guidelines on how to design and plan urban greenhouse constructions in future assessments. That will facilitate the incorporation of urban agriculture in cities based on consistent environmental assessments, ultimately contributing to the low-carbon future development of cities.
Article
A R T I C L E I N F O Keywords: Life cycle assessment Material flow analysis Resource use efficiency Structural modeling Urban agriculture Urban metabolism A B S T R A C T Urban and building systems are awash with materials. The incorporation of green infrastructure such as integrated rooftop greenhouses (iRTGs) has the potential to contribute to buildings' and cities' circularity. However, its greater sophistication than conventional agriculture (CA) could lead to a shift in environmental impacts. One of the key elements for greenhouse building-integrated agriculture (BIA) and CA to achieve high levels of environmental performance is their structural design, which largely impacts the economic and environmental life-cycle costs (by up to 63%). In this context, the study assessed iRTGs life-cycle material and energy flows and their environmental burdens at structural level (m-2 y-1) within life cycle assessment (LCA), based on a case study in Barcelona. A structural assessment following European standards allowed the identification of key design factors to minimize the environmental impacts of RTGs' structure within improvement scenarios. The assessment revealed that a steel structure in a business-as-usual (BAU) scenario contributed from 31.5 to 67.3% of the impact categories analyzed, followed by the polycarbonate covering material (from 21.8 to 45.9%). The key design factors responsible for these environmental impacts were ground height, ventilation design, building integration and urban location. The improvement scenarios compensated for additional steel inputs by up to 35.9% and decreased environmental impacts that might occur in the BIA context by 24.1% compared with the BAU scenario. The assessment also revealed that urban environments do not imply shifting environmental impacts per se, as greenhouse BIA structures can benefit from their advantageous characteristics or be compensated by optimized greenhouse structures.