Maximizing benefits of batteries in residential grid-connected PV-plants subject to partial shading

In this paper, a proposal for optimizing the utilization of batteries within grid-connected PV-plants is introduced and discussed. Batteries are utilized for obtaining both the conventional energy storage task and the maximum power generation of a PV-module operating under partial shading conditions. In practice, as an alternative to the conventional way of utilizing batteries as a centralized storage-bank, we propose to utilize batteries in a distributed framework in the form of “micro” battery-packs. By this way, the aforesaid micro battery-packs, if properly designed, can be utilized directly within circuitries of low-power (and low-voltage) boost-type DC/DC converters, to be profitably utilized in turn as high efficiency distributed MPPTs, so obtaining the maximization of the power generated by a PV-plant, also in presence of significant partial shading phenomena (or other mismatches among different series-connected PV-cells). Experimental and numerical data are presented, analyzed and discussed.