Agrivoltaics: the yield of the panels, and the light left for the crops
pvSpline models both agrivoltaic layouts and reports two results side by side: the energy the panels produce, and the light that reaches the crops under and between the rows.
Two agrivoltaic layouts
- Agrivoltaics (elevated): panels raised above the crops, set by the row pitch, the collector width, the height of their lower edge above the crop and the electrical effect of shading.
- Agrivoltaics (vertical bifacial): vertical bifacial rows between the crops, on the same row geometry. Picking it stands the modules up at 90° and turns them to face east, and a field never tuned before starts on an 8 m row pitch, a 2 m collector width and a 0.5 m clearance.
A light model for what grows underneath
Beside the yield, a dedicated model computes the light that reaches the ground. It samples a line across one row pitch and, at each point and each hour, tells whether the point lies in a row’s shadow and how much of the sky the neighbouring rows leave it. The average gives the ground light as a share of the open field’s, and the spread along the line the shade uniformity. The model runs alongside the yield and takes nothing from it.
The crop figures in the report
- Ground light, growing-season PAR and shade uniformity, on the agronomy page the report prints at the head of the agrivoltaic charts.
- The ground-light heatmap: the light available at crop level under the array, day by day and hour by hour.
- The transect: the annual mean ground light from one row to the next, under the row, mid-gap and under the next row, as a share of the open field’s.
The panels’ own yield
On the panels’ side, the row geometry sets the mutual shading between the rows, with separate lines for the direct beam and the diffuse light in the loss cascade, and the electrical effect of partial shading on the strings. A vertical bifacial field gains on its rear face, which is why it stands upright.
In 3D, through the seasons
The 3D site view lifts both layouts on their posts to their clearance, the vertical rows standing at 90°, over a ground where the crop grows, dries and is cut as you move the inspection date through the year.
Agrivoltaics in French law
In France, an agrivoltaic installation must contribute durably to farming on its parcel (Code de l’énergie, article L. 314-36), under the conditions the decree of 8 April 2024 sets. Whether a project qualifies is for the authorities that review it to decide; pvSpline gives the figures on the light the crops receive.
An agrivoltaic study in four steps
- Draw the field on the Map and assign its module.
- On the zone’s card, set Field to Agrivoltaics (elevated) or Agrivoltaics (vertical bifacial).
- Set the row pitch, the collector width and the mounting height.
- Run the simulation, then read the ground-light charts and the agronomy page of the report.
Questions
Does the light under the panels lower their yield?
No. The ground light is a result of its own, computed alongside. The panels lose what the row geometry shades, line by line in the loss cascade.
What does ground light mean?
The light reaching the ground under the array, as a share of what an open field receives at the same moment. The transect shows it from one row to the next, the heatmap day by day and hour by hour.
Elevated or vertical?
Both report the same crop figures. The elevated layout raises tilted panels above the crop at the clearance you set; the vertical bifacial one stands the rows upright between the crops, close to the ground, with a gain on the rear face.
The fastest way to judge a simulation tool is to run it on a project you already know.