Details on Solar Options in the Settings
Information about Solar Options tab in the Settings dialog of the dynamic cooing load calculation.
In this dialog you define how the program calculates the solar radiation.
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Solar Radiation
Enabled: Solar radiation is taken into account project-wide for the cooling load calculation and can be configured here. The solar radiation is calculated hourly. The exact calculation time can be adjusted in the drop-down list.
Disabled: Solar radiation and window settings for shading are not taken into account in the cooling load calculation. The cooling load calculation is performed based on the internal loads only. The shading configurations for windows and the loaded shading data remain intact and will be considered again once the solar radiation is activated.
Shading
You can select between two options for shading in the calculation of the dynamic cooling load, with consideration of solar radiation. The respective selection affects the settings under EAC (CDD/CDP only) in the Window Data dialog.
| Selection | Description |
|---|---|
| Calculation Based on the Window Configuration | The calculation of the thermal loads is carried out with consideration of the set window configuration. You configure the Window Data in the dialog. |
| Pre-calculated Values from File | The calculation of thermal loads is performed with consideration of shading data for the building model from an external data file (*eac file). This data file must be created with the LINEAR Solutions for Revit for the building model. This data file can then be imported using the Select button. |
Calculation Model
Specifies the calculation model according to which the program calculates the solar radiation. In VDI 2078, the program performs the calculation in the solar calculation model according to VDI 6007 part 2 (2012).
| Selection | Description using 12 o'clock as example |
|---|---|
| Calculation on the hour | The result for 12 o'clock is calculated at 12 o'clock. |
| Calculation at halfway point of the past hour | The result for 12 o'clock is calculated at 11:30. |
| Average of the past hour | The result for 12 o'clock is the average of the calculated steps from 11 o'clock to 12 o'clock. |
| Average around the current hour | The result for 12 o'clock is the average of the calculated steps from 11:30 to 12:30. |
Calculation steps
Number of calculation steps per hour for the calculation of solar radiation when Average of the Past Hour and Average Around the Current Hour are selected.
Options
Coefficient of reflection pg (ambient, external)
The reflection coefficient is used to calculate the power of diffuse solar radiation from ground reflection. Here you can change the reflection coefficient globally for the entire project. The reflection coefficient depends on the nature of the soil. Clicking 
opens the Ground Reflection Coefficient dialog, where you can select from a list of predefined reflection coefficients or create user-defined reflection coefficients.
global a(konv)
Enabled: You can enter a global value for a(conv) that is used project-wide. The value a(conv) determines the proportion of diffuse and direct solar radiation within the building that is convective radiation. Clicking opens the Convective Proportion of Solar Radiation dialog, where you can select the proportion of convective solar radiation based on the nature of the window, from a table according to the guidelines VDI 6007 Part 2 or VDI 2078. An activated Global a(conv) cannot be overwritten at room level in the Enveloping Surfaces dialog.
global IAC
Enabled: You can enter a global IAC to specify a project-wide shading coefficient for interior shading. The shading coefficient depends on the type of window. An activated Global IAC cannot be overwritten at room level in the Enveloping Surfaces dialog. Clicking opens the Shading Coefficient dialog, where you can select the shading coefficient for the internal shading.
Shading (VDI 2078) from
Enabled: You can specify a specific energy input, starting at which the configured shading should be taken into account in the calculation for windows according to VDI 2078. This is relevant, for example, for external shading, which automatically shuts down at a specified light intensity.
Disabled: The set shading for windows according to VDI 2078 is taken into account throughout.
Internal Shading (IAC) from
Enabled: You can specify a specific energy input, starting at which the shading becomes active for windows with automatic internal shading. These can be, for example, automatic indoor blinds that are lowered at the value set for global radiation.
Disabled: The shading for windows with automatic internal shading is taken into account throughout.