Solar carports, designed deck by deck and simulated
In pvSpline a carport is a building whose deck carries modules. Draw it over the parking rows, set the decks’ dimensions, and the placer packs the modules deck by deck; the run then simulates each deck as a free-standing array.
A building that carries modules
Set a four-corner zone’s Polygon type to Building and its Building model to Carport. The zone keeps its PV azimuth and tilt, which sets the deck tilt, with their sources, its module, its albedo and its power cap, and adds the deck’s own dimensions. It is the one building whose installed power counts in the totals, the production and the bill of materials.
Single slope or east-west butterfly
With Butterfly (E-W) on, as it is by default, each deck has two opposed slopes per pivot. The run simulates it as two faces of equal area at the deck tilt, one facing the azimuth and one the opposite way, with no row-to-row shading, so a bifacial module keeps its rear-side gain. With it off, the deck is one plane facing the azimuth.
Dimensions that drive the layout
| Dimension | What it sets |
|---|---|
| Height | The height of the deck, 3.31 m by default. |
| Width | The width of the deck, 6 m by default. |
| Length | The length of the deck, 26 m by default. |
| Row spacing | From one row of decks to the next, pivot to pivot, across the ridge: 16 m by default, which clears a butterfly deck and leaves a 6 m aisle. |
| Column spacing | From one deck to the next along the ridge, pivot to pivot: 26 m by default, which puts the decks end to end. |
| Butterfly gap | The gap at the ridge of a butterfly deck, 0.3 m by default. |
The deck placer reads these dimensions, typed in millimetres, so they change the packed layout as well as the 3D model. Its modules sit 2 cm apart in both directions.
Checked before it is built
Above the dimensions, a 3D preview draws four decks with their posts, the module grid and parked cars for scale; turn it, or pick an iso, front, side or top view. Clicking into a dimension draws that measurement in metres. When neighbouring decks would overlap, the preview names the smallest spacing that clears them, and a summary line warns when the low edge would sit below ground or under head height.
In 3D, in the permit and at the tariff
- In the 3D site view: the carport rises with its decks and casts its shade on the arrays around it, like any building.
- In the permit package: a supporting structure, with the height of the modules above the ground (déclaration préalable).
- In the bill of materials: a carport deck takes a racking kit like any array, for the structure lines.
- At the tariff: the EDF OA purchase obligation buys the output of installations on buildings, hangars and carports (tariffs in force).
Car parks and the APER law
In France, the APER law of 10 March 2023 requires outdoor car parks of more than 1,500 m² to be partly covered with solar canopies, on a timetable set by their size. pvSpline lays out and simulates those canopies like any other array, from the first sketch to the financial case.
A carport in five steps
- On the Map, draw a four-corner zone over the parking rows.
- Set its Polygon type to Building and its Building model to Carport.
- Keep Butterfly (E-W), or switch it off for a single slope, then set the decks’ height, width, length and spacings.
- Set the azimuth, the deck tilt and the module: the placer packs the decks.
- Run the simulation and read the carport’s yield with the rest of the site.
Questions
Does the simulation count a bifacial module’s rear side?
On a butterfly deck, yes: its two faces are simulated with no row-to-row shading, so a bifacial module keeps its rear-side gain, over the zone’s albedo.
Can one project mix carports and roof arrays?
Yes. Each zone keeps its own type and the totals add up. The shared rows for the tilt, the 3D height and the power cap reach the PV zones and the carport decks alike.
Which purchase tariff does a carport get?
The EDF OA purchase obligation covers carports as it covers buildings and hangars, within its power bands, at the CRE grid in force on the grid-connection request date: see the tariffs in force.
The fastest way to judge a simulation tool is to run it on a project you already know.