The following results are presented for two setups with different relative demand-to-production ratios, corresponding to different PV penetration levels. The array-to-load ratio (ALR) is the ratio of nominal array peak power to the mean load, in this case the annual mean load for detached houses. Two system setups with ALR of 2 and 8 are used. The relative sizes of load and production are shown in Figure 2. The first setup results in a small overproduction, corresponding to a penetration slightly above optimal from the grid point of view (cfr. [3]). The second setup causes a massive overproduction but nonetheless yields just enough to annually cover the household electricity demand.

Fig. 2. Average load (PL) and production (PS) for the whole year (left) and the summer months May, June
and July (right) at different relative system sizes (ALRs). In addition to the load profile for detached houses,
the corresponding load profile for apartments is shown for comparison purposes.

The main indicator of load matching considered here is the solar fraction, which is the fraction of load covered by PV. Since the overproduced power level is critical from the grid point of view, this is covered briefly.