Fig. 5 presents the values of the monthly averages of the daily energy produced in the park, per installed peak power. This system produces more energy in summer periods with a maximum average daily production of 34.8 kWh at July 2006 and July 2007. The production minimum occurred at December 2007 with a daily average production of 11.1 kWh.

At Table 4 we present the yearly irradiation and energy produced by PV Park system. The yearly irradiation measured, in the 15° tilted surface, is about 1 790 kW/m2 each year and the energy production is about 1 400 kWh per kW of peak power installed. The low production in 2006 year, despite the bigger irradiation, is due to an inverter failure during two weeks in the month of May.

This results show that the energy production by installed peak power of the facade system is about

28.6 % lower than for the park system, this is due mainly to the lower incident irradiation on the facade surface.