Conclusion
The impact of uncertainty in ground reflectance is practiced in this study.
This value in EnergyPlus is considering as average monthly equal 0.2.
However, according to literature, this value can be varied between 0.05 and
0.45. Regarding this analysis, two different scenarios are
evaluated. The first scenario considers a controlled shading strategy and
second one assessing the performance of a fix shedder. The total amount of
incident solar radiation on the building envelope with the respect of
ground radiation uncertainty is evaluated. The uncertainty in ground
reflectance is propagated on the building energy model and the analysis is performed for 5 years of weather conditions. In order to propagate
this uncertainty, different sets of samples are generated with Monte
Carlo sampling. The results provide a better overview of the performance
of each scenario, especially, on the lower and upper limits of shading
performance also the frequency of incident solar radiation for each hour
of a day.
This kind of analysis will be useful for designers to provide a more
confidence performance of proposed shading strategies. Also, this
analysis can use for analysis related to solar heat gains and inside
comfort conditions. This analysis could be used to reduce the
performance gap between reality and building energy simulations. As
observed in scenario 2.
The future work
The future work of this study will be composed of following tasks:
- Uncertainty quantification of different types of vegetation ( based on height, shape, density, etc.) and their impact on the shading factor, and the amount of reflected solar radiation from ground.
- Quantifying the variation in diffuse solar radiation based on different climatic stations in various locations of a city, as well as multiple years.
- Modeling an urban geometry with DART tool and incorporating the earlier results with the input data of the tool and quantifying the incident solar radiation on the building surfaces.
- Applying the previous steps on different shading strategies for assessing the reliability of each design choice, and creating comparative graphs based on the performance of each shading strategy.
Acknowledgements
This research is conducted by the support of a doctoral scholarship granted by Fondazione Fratelli Confalonieri. Moreover, the weather data using in this study is provided by Osservatorio Meteo Milano Duomo.