In brief
The simulation calculates a full year in one-minute steps and checks whether reflections from the PV areas reach the observation points. Before the start, the app checks that all inputs are complete; starting uses one simulation token. The result is saved together with a read-only copy of the inputs.
12.1 How to
- Work through the "To-Do List" under "Start Simulation". Every open item blocks the start; clicking it opens the menu or object concerned.
- Open "Start Simulation". The confirmation shows the cost (1 simulation token) and the project's balance; the batch analysis also starts from here (Ch. 13).
- "Start now": unsaved changes are saved and the server checks the inputs again (table below). If saving fails, the simulation does not start.
- The calculation continues on the server, even after the browser is closed. Progress is shown by the button in the sidebar and in the project overview (Ch. 4).
- When finished, "Go to results" leads to the report (Ch. 14). The result is stored in a new read-only version "‹version name› · Sim-Backup DD.MM. hh:mm" with the state at the start; changes made during the calculation remain in the working version.
What goes into the calculation is defined by the inputs in the editor: PV areas, module types, observation points with field of view, obstacles, far-field shading and terrain occlusion in the menu of the same name (Ch. 6).
12.2 Checks at start
The server rejects the start if:
| Case | Note |
|---|---|
| plan limit exceeded | table 12.3 |
| not enough storage | storage used plus 100 MB for the result |
| no simulation token in the project | purchase in Ch. 3 |
| another simulation of the account is running | across all projects, batch analyses included |
| corner of a PV area outside the project area | the message names the areas (Ch. 5) |
| polygon self-intersecting or without extent | Ch. 7 |
| excluded area on no PV area, or PV area fully covered | Ch. 7.7 |
| terrain occlusion on, horizon of an observation point cannot be calculated | Ch. 6 |
12.3 Tokens and limits
| Limit per simulation | Free | Pro |
|---|---|---|
| PV areas | 3 | 50 |
| Observation points | 30 | 100 |
| Obstacles | 10 | 100 |
An area with east-west dual orientation counts once. Each simulation costs one token, regardless of size and duration. No token is needed for filters, figures and base maps in the report, the pre-analysis (Ch. 11) and the worst-case combination (Ch. 13).
Calculation parameters cannot be changed; all plans calculate the same way: reference year 2025 (365 days), time step 1 minute, minimum sun elevation 0° (a higher threshold is set as a filter in the report, Ch. V.8), solar disc 0.53°, calculation grid at most 0.125° (Ch. V.2), standard time of the time zone. Full list: Ch. V.9.
12.4 Points to note
- One simulation per account at a time (section 12.2). "Cancel & restart" ends the running one.
- Cancelling by the user discards the partial results and does not refund the token. If the calculation fails, the token is refunded automatically.
- Every simulation creates a new version. Older results remain until their version is deleted.
- "Invalid input data. Check the project data." means incomplete or contradictory calculation data; "Calculation server not reachable" allows a new start after a few minutes.
- There is no e-mail notification on completion.
Details: duration, error cases
The calculation time depends mainly on the number of observation points, the size and proximity of the PV areas and the number of reflections. "waiting for a free compute slot" means the computing capacity is busy; "time window w/W" means an observation point with a very large number of reflections that is calculated in sections.
The server ends a simulation that has shown no sign of activity for more than two hours as failed and refunds the token. If the result version cannot be created, the simulation counts as failed and the token is refunded.
Weather and cloud cover are not included; direct irradiance applies to a clear sky (Ch. V.5, Ch. VII).