*3.1. Standard Method 1*

It is based on the calculation of the distance (D) between the PTCs as a function of the height of the sun (h) for whom the facility was designed. Figure 3 shows the geometry to derive Equation (4):

$$\mathbf{D} = d + d' = \mathcal{W} \cdot \frac{\cos \alpha}{\text{tg } h} + \mathcal{W} \sin \alpha \tag{3}$$

$$\mathbf{D} = \mathcal{W} \cdot \left( \frac{\cos \alpha}{t \lg h} + \sin \alpha \right) \tag{4}$$

where *W* is the width of opening plane and α is the tilt angle relative to the vertical of the collector (azimuth of the panel). α is calculated to achieve sun rays perpendicular- Collector along the entire operating time of the solar plant. α is the solar tracking parameter which varies continuously all the time depending on the time, day, and location of the PTC facility.

**Figure 3.** Geometry on a PTC for the sun's rays (frontal view).

In this way, the shadow gets a horizontal spacing D since the first line of the PTC being h > h', see Figure 4, and so the second line must at least be placed in the PTC2h. In case the sun gets a height of h', the shading would have a horizontal spacing D', and the second PTC line would be positioned in PTC2h'.

**Figure 4.** Row alignment minimum PTC depending on the solar altitude (Standard Method 1).

Figure 4 shows the shadow geometry of the first PTC line (PTC 1) over the second PTC line (PTC 2 h).
