Prepare weather and resource data
The plant needs a resource year that matches its location and its equipment. Use the Weather tab to acquire data, inspect what the project holds and select a suitable year.
Check the project first
Set the site coordinates and time zone before acquiring weather. In Weather, inspect In this project and Cached weather years. Reuse appropriate data already held by the project.
The hybrid build reads whole-year hourly environmental series: 8,760 points at a 3,600-second interval. A series with another shape can exist in the project but is reported as unused by this build. It is not silently resampled.
Fetch from NASA POWER
- Open Weather → NASA POWER under Get weather.
- Choose the mode and year or year window offered by the form. Read the estimated requests and the realization selected for attachment.
- Select Fetch weather. Complete any network-access approval shown by your configured policy.
- Wait for the fetch to finish. Read its source, channel and attachment summary. A fetch configured only to inspect data can report Nothing was attached.
- Confirm the intended channels appear under In this project.
- Return to Design, select those series and read the build notes. The notes identify what the build used or skipped.
A multi-year request can fill the year cache for risk studies while attaching one realization to a design. These are separate outcomes: an attached year is not itself a multi-year ensemble.
Import a file
- Choose From a file, then Choose weather file.
- Set Weather file format to EnergyPlus EPW, TMY3 CSV or Custom CSV.
- For custom CSV, map the available channels using the form’s zero-based column indices and header-row setting. Column 0 is the first column. Do not apply custom mapping to EPW or TMY3.
- Select Import weather file.
- Inspect the imported channel summaries and source notes, then select the relevant series in Design.
Imported clock-time data are not automatically shifted into local solar time. Check the file’s time convention, daylight-saving treatment and start of year before comparing an hourly load with solar production.
Inputs and checks
| Input | Check |
|---|---|
| Irradiance | Correct channel and units: GHI, DNI and DHI are different quantities. |
| Temperature | Air temperature in the imported or fetched channel’s stated unit. |
| Time series | Whole-year coverage, hourly interval and the intended time basis. |
| Location | The actual site, not an approximate coordinate inferred from its name. |
| Provenance | Source, year or representative-year method, and any recorded assumptions. |
Do not substitute a fabricated DNI/DHI split when the build requires channels the source does not provide. Missing data must remain visible.
If acquisition fails
A busy message means another weather operation is active for the project. Wait for it or cancel it before starting another. A mapping error needs a corrected file-format choice or column mapping. A contract error needs valid annual data, not a relaxed sample-count check.
Offline work requires suitable cached or imported data. A project without them cannot fetch a new weather year offline. Imported data also do not populate the multi-year cache required by ensemble searches.
See Plant simulation and Sensitivity. This guide describes the September 2026 development build.