Every parameter and its default

Every field in the input panel ships with a working default, so a first run needs none of them changed. Load a boundary file, click Generate Layout, and the plant is built from the values on this page. The boundary file is the only input with no default — see Boundary files.

Two things change what you see: the mounting type decides which array group appears, and the electrical mode retitles the inverter group and relabels several rows. Both are chosen at launch — see Choosing a design mode.

The groups below are in panel order, top to bottom, and the rows within each table are in the order the fields appear on screen.

Which groups you see

Both choices are made at launch. To move to the other electrical mode afterwards, use File ▸ Move to String / Central Window…, also on the toolbar as ⊕ Move to String / Central Window.

Module specifications

Always shown. In depth: Module specifications.

Two buttons sit with this group:

• Load .PAN reads a PVsyst module file and fills in the wattage, the long side and the short side. When the file declares a bifacial module it also ticks Bifacial module and fills φ, and it recomputes the temperature loss. Dimensions are accepted in metres or in millimetres.
• View opens a read-only viewer of the loaded module file, with tabs Basic data, Sizes and Technology, Model parameters, Additional Data and Graphs.

After a module file is read the application asks "Calculate the number of modules in series automatically?", with Auto and Manual buttons. See String sizing.

The bifaciality tooltip gives a typical φ of 0.65–0.80 and a typical bifacial energy gain of 5–15 % over a monofacial module.

MMS-Table configuration

Fixed Tilt only. In a tracker design this group does not appear. In depth: Table configuration.

Table dimensions follow from the counts and the gaps:

table width  = modules per row × module E-W dimension
             + (modules per row − 1) × gap between modules E-W

table height = rows per table × module N-S dimension
             + (rows per table − 1) × gap between modules N-S

Both options at the bottom of the group are covered together on Maximize placement and half tables.

Tracker configuration

Single Axis Tracker only. This one group replaces both the table group and the spacing group. In depth: Tracker configuration.

A live preview line under the group reports Aperture (E-W), Length (N-S), GCR and Modules/tracker as you type:

aperture   = modules across × module E-W dimension
N-S length = strings × modules per string × module N-S dimension
GCR        = aperture / tracker E-W pitch
modules    = modules across × strings × modules per string

Spacing and tilt

Fixed Tilt only. Both values are derived from the site latitude unless you override them. In depth: Spacing and tilt.

The automatic rules, both shown in the group's own tooltips:

tilt  ≈ latitude × 0.76 + 3.1°
pitch = L·cos(tilt) + L·sin(tilt) / tan(solar elevation)

L is the table height in the tilt plane. After a layout runs, the derived values are reported inline — "Auto → 12.3° (latitude-based)", "Auto → 7.42 m (no-shading, latitude-based)" — and pre-filled into the override boxes so you can start from them.

Reported GCR is the table height divided by the row pitch.

Site parameters

Always shown. These four settings decide how much ground is available before a single table is placed, and how much equipment goes on what remains. In depth: Site parameters.

The corridor tooltip recommends raising the setback for higher-voltage lines, for example 30 m per side for a 400 kV line.

Structures and shadow

Always shown. Footprints are Length (E-W) × Width (N-S), and each carries a Height that drives the shadow footprint. In depth: Structures and shadow.

Every length and width above accepts 0.0–500.0 m and every height 0.0–200.0 m, to one decimal place, and the ranges are the same for all four structures. The two arrester fields are the exception in the group: they accept a value and then feed nothing at all, not even the project file, so both return to the figures above when a saved project is reopened.

Topography

Always shown, and does nothing until enabled. In depth: Topography.

Any terrain failure — no network, an unreadable file — is non-fatal. The layout proceeds without terrain exclusion. Contours draw green for low ground through blue to red for high, under the Terrain switch, and the excluded area is reported in acres.

String inverter or SMB

Always shown, with the group title and the row labels following the electrical mode: String Inverter in string mode, SMB – String Monitoring Box in central mode. In depth: Inverters and cable calculation.

Two buttons sit with this group:

• Load .OND reads a PVsyst inverter file. Its PmaxOut figure drives the plant AC capacity, falling back to Pnom when PmaxOut is absent.
• View opens a read-only viewer with tabs Main parameters, Efficiency curve, Additional parameters, Output parameters, Sizes and Technology and Commercial data.

In central mode, a maximum of 4 central inverters are housed in one control room building.

Energy yield

Always shown. Nothing here affects where a table goes — it decides what the placed plant is predicted to generate. In depth: How yield is calculated.

Weather source

Two mutually exclusive options. In depth: Weather data.

Selecting the file option pops a format reminder: exactly 3 columns in order — an hourly timestamp, GHI in W/m², and ambient temperature in °C. A full year is 8 760 rows, and a header row is optional and detected automatically.

The application accepts more than that reminder suggests. Column names are matched flexibly, and an in-plane irradiance column is accepted as well:

When the file carries a temperature column, monthly average temperatures come from the file instead of from the seasonal model.

Irradiance and temperature inputs

The four mounting configurations and their coefficient pairs:

They feed the module temperature, and through it the temperature loss:

T_module = T_ambient + G × exp(a + b × W)
Loss (%) = |μPmpp| × (T_module − 25)

W is the wind speed and μPmpp is the module's power temperature coefficient, read from the module file. G is the average operating irradiance derived from GTI as the smaller of 900 W/m² and GTI × 1000 / (365 × 8), or 600 W/m² when GTI is still 0. The computed module temperature is displayed beside the temperature loss row, with a formula trace underneath. See Temperature losses.

Performance ratio breakdown

Every loss below is a percentage, and together they give the performance ratio the yield is multiplied by. In depth: Losses and performance ratio.

Degradation

In depth: Lifetime and P-values.

Year 1 (actual) = capacity (kWp) × specific yield × (1 − 1st year degradation)
Year n (n ≥ 2)  = Year 1 (actual) × (1 − annual degradation)^(n−1)

Probabilistic yield

The three probability columns in the summary table are named from these three fields, so a report reader has to read the header rather than assume P50, P75 and P90.

The tooltips give the two standard cases:

P75 = P50 × (1 − 0.674 × σ)
P90 = P50 × (1 − 1.282 × σ)

Parameters set outside the input panel

Three tools carry their own inputs, and they have defaults of their own.

Pile pattern. Each pile is a circle centred on a coordinate you enter against one reference table, and the pattern is stamped onto every table in the plant. The pile radius defaults to 0.15 m. See Piles.

Robotic module cleaning. The robot's battery range, where 0 means no limit; whether the run must be out and back on one charge, which defaults to on; and the span of a standard inter-table bridge, which defaults to the gap already set between tables or trackers. Nothing is bridged unless you tick it. See Robotic module cleaning.

Simulation with AC capacity. A target AC capacity and a target DC to AC ratio. The maximum practical ratio is user-adjustable and defaults to 1.5× for string inverters and 1.4× for central inverters — a design overload limit, not the inverter's nameplate DC input. See Sizing from an AC capacity.

Values the application derives rather than asks for

Where to go next