Method for controlling the orientation of a solar module with two photoactive faces

A solar module comprising:

• a single-axis solar tracker orientable about an axis of rotation for an orientation of the solar module allowing tracking the Sun during its rise and its descent from east to west, the solar tracker being actuatable in rotation about the axis of rotation by an actuation system;
• a photovoltaic device supported by the solar tracker and having a photoactive upper face facing the sky and a photoactive lower face facing the ground;
• an upper measuring device configured to measure a distribution of incident solar luminance originating from incident solar radiation which comes from the sky and which is capable of reaching the upper face of the photovoltaic device, the distribution of the incident solar luminance being established according to elevation angles corresponding to orientations of the solar module about the axis of rotation;
• a lower measuring device configured to measure a distribution of reflected solar luminance originating from albedo solar radiation which corresponds to the reflection of solar radiation on the ground and which is capable of reaching the lower face of the photovoltaic device, the distribution of the reflected solar luminance being established according to elevation angles corresponding to orientations of the solar module about the axis of rotation;
• and
• a control unit coupled to the upper and lower measuring devices, and to the actuation system for controlling the rotation of the solar tracker, wherein the control unit is configured to:
• convert the measurement of the distribution of the incident solar luminance into an incident luminance mapping defining a distribution of luminance values according to upper strips, established according to a horizontal first direction parallel to the axis of rotation, and according to upper columns, established according to a horizontal second direction orthogonal to the first direction, where each upper strip is associated with an elevation angle and each upper column is associated with an azimuth angle;
• convert the measurement of the distribution of the reflected solar luminance into a reflected luminance mapping defining a distribution of luminance values according to lower strips, established according to the first direction, and according to lower columns, established according to the second direction, where each lower strip is associated with an elevation angle and each lower column is associated with an azimuth angle;
• calculate, for each upper and lower strip, an equivalent luminance value from a set of luminance values taken in the considered strip;
• calculate, for theoretical elevation angles corresponding to orientations of the solar module, luminance values perceived by the upper and lower faces of the photovoltaic device from the equivalent luminance values calculated for all the strips and from angular differences between the theoretical elevation angles and the elevation angles associated with the strips;
• determine a theoretical elevation angle associated with a maximum of the perceived luminance value;
• select the theoretical elevation angle as an optimum orientation;
• and
• control the orientation of the solar tracker according to the optimum orientation.