Division 1 The standard deviation of arithmetic mean of the peak power output is to be calculated by formula (1).

Formula (1):

$$\Delta \overline{P_P}=\sqrt{\frac{\sum _{i=1}^n{\left(P_{P_i}-\overline{P_P}\right)}^2}{n\left(n-1\right)}}$$

Where:

$\Delta \overline{P_P}$

Standard deviation of arithmetic mean of the peak power output (Wp);

P_Pi

Measurement value of the peak power output (Wp);

$\overline{P_P}$

Arithmetic mean of the peak power output (Wp);

n

Number of measurements.

The gain of additional electric power depends on the available electric on-board storage capacity which must be verified. If the capacity is below 0,666 Ah per Watt peak power of the PV panel, the solar radiation arising on sunny and clear summer days cannot be used completely because of fully charged batteries. In this case the solar correction coefficient referred to in point 2 is to be applied to derive the usable share of the incoming solar energy.