## 5 Conclusions  
In this study, different kinds of QM and a classification RF were used to predict the wind speed and direction over the roof of a building for a period of 10 years using ERA5's data as input. These predictions were then used along different modeled power curves and different suppositions about the effect of the building's geometry on the wind speed to come up with estimations of AEP and CF for an horizontally mounted Savonious type turbine. Even if the method was developed with the ROSEO-BIWT in mind, some aspects can also be applied to other wind turbine designs. One of those aspects is the experiment made on the effect of the skew angle on the performance of a building integrated turbine. Apart from confirming some previous findings, like the fact that the performance of VAWTs increases with non-zero skew angle values, we also propose a way to incorporate these findings in a wind resource method. That is the absorption range, which is key to the selection of a facade and could also we used to select buildings according to their orientation. A more detailed knowledge of the effect of the skew angle could lead to more sophisticated ways to incorporate wind direction to the wind resource assessment. One of them could be modeling different power curves for different skew angles within the absorption range. Important lessons can also be extracted from the use of QM. The fact that, when using every wind direction, even the simple calibration gets very good results in terms of PDF means that it can be used for estimating the potential energy production of wind turbines that work with every wind direction. Moving on to categorized calibrations, the success achieved by using directional and seasonal criteria seems to suggest that better results could be achieved by refining these criteria (by using more wind directions or by separating by month instead of season, for example) or by incorporating new criteria. However, the results bring up a question: why did the directional calibration perform better that the combined one even if seasonal categorization improves the results over uncategorized QM? That will have to be answered by analyzing more locations and by comparing the outcomes of different training data set sizes. For now, the best explanation is that both seasonal and directional categorization improve the calibration, but, in this study, not enough was available to properly train the combined calibration. Apart from QM, RF was also used as a way to take into account the sensibility to wind direction. Its prediction was used to filter the wind speed predictions made via QM before implementing them on power curves. This procedure was used because QM has a great capability to match the calibrated wind speed's PDF with that of the measurements. However, the use of RF opens up another possibility, which is using it to totally replace QM. This would be by applying regression RFs to the wind's \(u\) and \(v\) components. Another pending task is finding better ways to measure or estimate the concentrating effect of the wind on the edge between a facade and the roof due to the geometry of the building and its surroundings. An ideal way to validate such a method would be installing a cup anemometer directly on the edge with its rotation axis on a horizontal position, parallel to the edge, just like a horizontally-mounted Savonious would be. Conceptualization, O.G., M.d.R., A.U., M.Z.-M.d.M., and A.G.-A. ; methodology, A.G.-A. ; software, A.G.-A. ; validation, A.G.-A. ; resources, A.U., M.d.R. ; data curation, A.G.-A. ; writing--original draft preparation, A.G.-A. and A.U. ; visualization, M.Z.-M.d.M. ; supervision, O.G., A.U., M.Z.-M.d.M., M.d.R. and A.G.-A. ; project administration, A.U., M.d.R. ; funding acquisition, A.U., M.d.R. All authors have read and agreed to the published version of the manuscript. This research was funded by the University of the Basque Country (UPV/EHU) GIU 17/002, and the Basque Autonomous Government's BEAZ-SPRI grant for the creation of innovative enterprises (ROSEO EOLICA URBANA).