ROOFTOP GREENHOUSES: Comparison between Farm builder and IDA ICE energy simulation software

Abstract: Rapid global urbanization is a major concern for the food production system, as it is recognized that relying on conventional methods of distant large-scale farming contributes significantly to greenhouse gas emissions. One of the key strategies to address this challenge is rooftop greenhouses (RTG), which are greenhouses built on unoccupied rooftops. Besides that, this technology goes beyond crop production to offering possible alternatives of reducing the operational energy demand for the host building as well as greenhouse itself. In line with this, a computational based simulation tool (Farm builder) incorporating energy and crop growth models was recently developed for simulation of building integrated agriculture such for RTG and to predict the energy consumption associated with this application. However, as this tool has been able to demonstrate its potentialities in evaluating the implementation of RTG models, it is also needed to reflect on the modelling procedure, inputs, output information and most importantly to investigate these certain aspects in comparison to other simulation tool. Thus, this thesis aims to present a comparison study between Farm builder and IDA ICE energy simulation software, as one of the simulation tools which have been also used to perform energy simulation involving RTG application. The analytical comparison was based on two case studies: a single zone model defined in the Building Energy Simulation Test (BESTEST) validation procedure and IKEA warehouse building located in Malmö which was integrated with RTG in a previous study. A number of test cases were performed and inputs parameters that are applicable to both tools were assessed including HVAC system operations. The results from this study show that, there exists an acceptable level of agreement between Farm builder and IDA ICE in terms of evaluating the host building model, as the validated EUI results against energy measurement were relatively close to each other. However, the largest discrepancies between both simulation tools were observed for the outcomes of integrated RTG. Overall, the findings of this study suggest that Farm builder provides reasonably promising results, and the analysis of the observed trends in discrepancies also give possible insight on the effect of some limitations, contrasting capabilities and inputs data needs between both tools to perform energy simulations.