"Designing for sustainability requires many analyses, and an understanding of the incident solar radiation on a building façade is one of those analyses. It is particularly compelling to be able to do this analysis from within Revit. The new Solar Radiation Technology Preview allows users to study incident solar radiation on a building form within the conceptual massing environment available to all Revit Architecture and Revit MEP users. There are many examples of how the information can be used, but some of the common ones are:
Studying how incident solar radiation on the façade of a specific form differs by orientation. This could be as simple as analyzing a basic rectangular form. It is easy but important to look at incident solar radiation on pitched roofs to understand the impact of various roof pitches and nearby shading elements early in the design process if solar panels are being considered.
To understand the relative importance of glazing for daylighting and solar heat gain of the building, it is useful to quantify the difference between the incident solar radiation that occurs on the lower floors vs. the higher floors of a tall building. This is especially significant in an urban context. Studying incident solar energy is one step towards understanding what types of glass might be appropriate different façades or floors. If the solar radiation on the north façade or lower floors is much lower than the flux on the southern or high floors, varying glass type and performance by face may be appropriate.
Much of the analysis associated with low carbon building design and sustainability is very numerical and not visually compelling. The solar radiation add-in is a great way to provide visual feedback within the context of a design whether as a means to communicate a design choice, or as part of a presentation.
It is worth repeating here that analyses for sustainability, including solar radiation analysis, should be done very early in the design process, and then repeated as needed when the form and design evolves. This new technology preview is available within the massing environment, which facilitates its early use.
The user chooses a weather file which contains the raw solar data required for the analysis, then chooses a date and time range for the analysis, and finally selects the surfaces to be analyzed.
The user has the ability to set the number of divisions or tiles that a surface gets sectioned into for the analysis, with the associated computation time implications. The results can be displayed as cumulative, peak or average values in user chosen units. The computation time varies depending on the calculation resolution, but examples shown here take approximately 10 seconds for the simplest analysis for the simplest form, to approximately 20 seconds for the more complicated form.
Finally, once the users are satisfied with their analyses, they can choose to publish the results in the form of images or output to a printer."