Every parameter and its default

Every input ships with a working default, so a first run needs none of them changed. Select 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.

The inputs sit on five stage tabs under the pinned Generate Layout button: Site · Array · Electrical · Yield · Tools. Every card on a tab is a collapsible group, expanded by default. Two things change what you see: the mounting type decides which array cards appear, and the inverter topology retitles the inverter card, the transformer card and several rows. Both are chosen at launch; the ribbon's design chip ("Fixed tilt · String inverter ▾") opens another window for a different combination — see Choosing a design mode and The main window.

The tables below are in tab order, then card order, and the rows within each table follow the order of the fields on screen.

The five tabs

Inputs and the last run

The layout remembers the inputs it was generated from. Change any field on the five tabs and the layout is out of date: the button reads Regenerate Layout, the changed field turns amber, and exports and Calculate Energy are refused until you regenerate or change the value back. The exceptions are GHI and GTI, values the application fills in itself, and the ACCB & Transformer card, which regroups the plant on the spot. Tilt and pitch count only while their override is ticked, the temperature and shading losses only while they are not computed automatically. See Out-of-date results.

Site tab

Input Boundary File

A read-only path field with the placeholder "Select a boundary file…", a Browse… button, and a round ⓘ button that opens the KMZ File Preparation Guide. Under the field a line reads "Supported formats: KMZ, KML, DXF, DWG, JPG, PNG, GIF, BMP, TIFF"; while the field is empty an Open sample site link beside it loads the bundled sample — one boundary with a pond, a transmission line and an obstruction. Once a file is read that line becomes the boundary summary, for example "1 boundary · 1 obstacle · 1 line obstruction".

In depth: Image boundary, and the CAD drawing page linked under Site reference.

Site Parameters

These 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. How the control rooms are counted and placed is on Inverter control rooms.

Structures & Shadow (keep-clear)

A grid with the column headers L, W and H: Length (E-W) × Width (N-S), plus a Height that drives the shadow footprint. The compact fields carry no unit; the row labels do ("ICR (m):"). In depth: Structures and shadow.

Every length and width 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 saved with the project, compared with the last run like any other input, and printed among the Word report's input parameters — but nothing in the layout uses them: no placement, no shadow, no quantity, no drawing.

Topography (slope-aware exclusion)

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, switched on by the Contour / terrain row of the Layers ▾ popover, and the excluded area is reported in acres.

Array tab

The tab opens with a read-only MOUNTING chip — "Fixed-tilt MMS tables" or "Single-axis tracker" — that records the choice made at launch.

Module Specifications

Shown in both designs. In depth: Module specifications.

• Load .PAN 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. The file row then shows the module label in green.
• View opens the read-only viewer with the tabs Basic data, Sizes and technology, Model parameters, Additional data and Graphs.
• Loading a module file asks nothing. String sizing is opened from the Size… button beside Modules per row (fixed tilt) or Modules per string (N–S) (tracker) — see String sizing and the string-sizing fields below.

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 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 card are covered together on Maximize placement and half tables.

Spacing & 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 card'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 still-greyed-out boxes so you can start from them. Reported GCR is the table height divided by the row pitch. A CAD or image boundary continued as Layout only has no latitude unless you typed one in Site reference; without one, tick both overrides and set tilt and pitch by hand.

Tracker Configuration

Tracker only. This one card replaces both the table card and the spacing card; its sections are Tracker Geometry, Row Spacing and Tracker Parameters. In depth: Tracker configuration.

The unit dimensions as placed:

n along tube    = strings per tracker × modules per string
aperture (E-W)  = modules across × module E-W dimension
                + (modules across − 1) × gap between modules E–W
length (N-S)    = n along tube × module N-S dimension
                + (n along tube − 1) × gap between modules N–S
modules/tracker = modules across × strings per tracker × modules per string
N-S step        = length + N–S service gap

A green preview line under the card reports Aperture (E-W), Length (N-S), GCR and Modules/tracker as you type. Treat it as indicative: it leaves the module gaps out of the first two, so on the shipped defaults the previewed length is 1.10 m short of the placed one.

Electrical tab

String Inverter, or SMB – String Monitoring Box

The card title and the row labels follow the topology: String Inverter in a string design, SMB – String Monitoring Box in a central design. In depth: Inverters.

• Load .OND shows the manufacturer and model on the row. Its AC power rating, multiplied by the inverter count, gives the plant's inverter capacity and AC capacity. Loading it does not set the inverter efficiency on the Yield tab.
• The same file feeds the next card: PmaxOut sets the transformer loads and the power transformer, the output voltage sets the LV voltage, and the maximum AC current sets the inverter feeder current in the cable schedule. Loading it after a layout regroups the plant at once and marks the layout out of date.
• View opens the read-only viewer with the tabs Main parameters, Efficiency curve, Additional parameters, Output parameters and Sizes and technology.
• In a central design the central inverters are counted per ICR block — the block's boxes ÷ Max SMB per Central Inverter, rounded up, at least one and at most 4 in one control room building.

ACCB & Transformer, or Transformer

The second card groups each ICR block's inverters into AC combiner boxes (ACCBs) and the ACCBs into transformers, and sizes the power transformer at the main control room. It is titled ACCB & Transformer in a string design and Transformer in a central design, where central inverters feed the transformers directly. In depth: ACCB and transformers.

• Rating lists take commas, semicolons or spaces, and are read when you press Enter or leave the field; the list is then sorted, duplicates dropped and rewritten tidily. An invalid list keeps the previous ratings, with a hint under the field such as "List at least one rating. Keeping 2500, 5000."
• The answer line at the foot of the card reads "Now: Generate a layout first" until a layout exists, then, for example, "Now: 12 ACCBs · 4 transformers: 4 × 16,000 kVA", or "… · ratings need the OND file" without an inverter file.
• An edit regroups every plot at once, without a Generate. Nothing is re-placed or re-routed, the layout does not go out of date, and the Summary view follows. A stored automatic diagram is not redrawn — choose Automatic again in the SLD view — and the next visit to the BOM view recomputes the list, discarding hand edits.
• The power transformer exists only when a plot holds a main control room and an inverter file is loaded. It carries every inverter on the site — central inverters in a central design — because the other plots feed through their unit substations:

need  = inverters × PmaxOut (kW) ÷ 1000 × margin ÷ derating   (MVA)
count = the larger of 1 and need ÷ largest listed rating, rounded up

Each unit then takes the smallest listed rating at or above need ÷ count.

Cables

The third card. In depth: Cable options.

The lead and the return run add nothing on a tracker design; the slack applies to both.

Yield tab

Run Energy Calculation

Not inputs, but the card the tab opens with: Calculate Energy, 📊 Show Energy Chart, an Interval: selector (1 min, 10 min, 15 min, 30 min, 1 hour) for the time-series export, Export TMY data CSV, and a status line. All are disabled until a layout exists, and Calculate Energy is also disabled while the layout is out of date and on a site whose location is unknown. In depth: How yield is calculated and Time series.

Energy Yield

Nothing here affects where a table goes — it decides what the placed plant is predicted to generate. Its fields are still inputs to the last run — GHI and GTI aside — so changing a loss makes the layout out of date.

Weather Data Source

Two mutually exclusive tick boxes. In depth: Weather data.

Selecting the file option pops Hourly GHI File — Required Format: 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 site conditions

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. Once a module file is loaded a formula trace under the wind speed shows the working. See Temperature losses.

ADVANCED expanders

Three expanders, collapsed by default, each header carrying a live summary.

Performance-ratio losses (summary "≈ 19.0 % combined" on the defaults). Every loss is a percentage, and together they give the performance ratio the yield is multiplied by. In depth: Losses and performance ratio.

Degradation & lifetime (summary "0.40 %/yr · 30 yr"). 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)

Uncertainty & exceedance (summary "P50 / P75 / P90"). The three probability rows of the Summary view are named from these fields, so read the row label 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)

Tools tab

No parameters of its own — this tab edits the generated layout and opens the studies. It can be opened at any time; before a layout its tooltip reads "Generate a layout first" and its buttons are greyed out, except Robot count from DXF…. Its cards are Obstructions (Draw Rectangle, Draw Polygon, Undo Last, Clear All), the tip "Tip: Click and drag a blue ICR to reposition it." once a run has placed control rooms, Main Control Room & Objects (Place MCR, Remove MCR, Place Object, Remove Objects) and Studies, whose five buttons are, in order:

1. 🔆 Simulation with AC Capacity
2. 🤖 Robotic Module Cleaning
3. Robot count from DXF…
4. 🌓 Shadow View (row spacing)
5. ⚡ Earthing Design

Robot count from DXF… and Earthing Design… are also on the Tools menu. See Obstructions and Site equipment; the studies' own inputs are in the next section.

Parameters set outside the input panel

Seven windows carry their own inputs, with defaults of their own.

Site reference

Opens when you choose a CAD drawing or an image with Browse…. Nothing is pre-filled. The choice and the image scale are saved in the project and reused at every Generate. In depth: CAD drawing.

Layout only leaves the location unknown: no energy yield, no KMZ, no satellite imagery, and — without a latitude — no automatic tilt, row pitch or building-shadow clearance.

String sizing

Opened from Size…. It needs a module file and an inverter file. In depth: String sizing.

Simulation with AC Capacity

Needs a module file and an inverter file. In depth: Sizing from an AC capacity.

Robotic module cleaning

Sizes the fleet for the generated layout. In depth: Robotic module cleaning.

Nothing is bridged unless you tick it in the list of gaps. The fleet result is saved with the project; the window's own answers are not, and it opens on the defaults every time.

Robot count from DXF

Sizes a cleaning fleet from any plant layout DXF, with no layout generated, and writes nothing into the project. In depth: Robot count from DXF.

The Layers view assigns each layer of the drawing a role, guessed from its name; only the tables layer is required.

Earthing Design

A preliminary IEC earthing calculation for the generated layout, with IS 3043 and IEEE 80 shown as cross-checks. There is no run button: the window calculates when it opens and again as you edit. Its inputs are not saved in the project; they are remembered only while the application window stays open. The fields, their defaults and what each one drives are on Earthing design. The inputs are in seven groups, in this order:

Pile layout

Opened from Piles: OFF or Edit-Pile ▸ Define Pile Layout…. In depth: Piles.

Full tables carry the full pattern. Half tables carry a half pattern — derived from the full one by default (same end overhangs, even spans, and on a tracker a drive pile at the centre), or your own once you edit it on the Half tab; Reset to derived returns to the derived one. Offsets are measured from the unit's own south-west corner. The patterns are saved with the project and carried across a Generate; the overlay's ON / OFF is not saved.

What a project file keeps

A saved .slp project keeps every input on the five stage tabs:

• Boundary and location: the boundary file path, the Site reference choice and the image scale.
• Files: the paths of the module, inverter, hourly weather and contour files — kept even when a file has gone missing.
• Array, Site, Electrical and Yield: every field on this page, including Structures & Shadow, Topography, the three cable allowances, Maximize placement, half tables, the Place Lightning Arresters tick, the shading auto-compute tick, ground clearance and the ACCB & Transformer card's rules.
• Pile patterns: full, half and the radius.

It also keeps the layout, the control rooms, inverters and cables, the MCR, USS and objects, drawn obstructions, sketch elements and hand-drawn trenches, the terrain and energy results, the BOM as edited, the SLD and its background, the electrical grouping, the cleaning fleet result, and the record of the inputs the layout was generated from.

Not saved: the Earthing Design inputs, the Robotic Module Cleaning window's answers, anything in Robot count from DXF, the AC-capacity window's ICR block AC (the ICR Block value it wrote is saved), and view state — the Layers toggles, Satellite, Wireframe and Piles: ON/OFF. See Projects.

Values the application derives rather than asks for

Where to go next