Shared Solar and Battery Storage Configuration Effectiveness for Reducing the Grid Reliance of Apartment Complexes

Abstract

More than 2 million houses in Australia have installed solar photovoltaic (PV) systems; however, apartment buildings have adopted a low percentage of solar PV and battery storage installations. Given that grid usage reduction through PV and battery storage is a primary objective in most residential buildings, apartments have not yet fully benefited from installations of such systems. This research presents shared microgrid configurations for three apartment buildings with PV and battery storage and evaluates the reduction in grid electricity usage by analyzing self-sufficiency. The results reveal that the three studied sites at White Gum Valley achieved an overall self-sufficiency of more than 60%. Owing to the infancy of the shared solar and battery storage market for apartment complexes and lack of available data, this study fills the research gap by presenting preliminary quantitative findings from implementation in apartment buildings.

Energy Allocation Strategies for Common Property Load Connected to Shared Solar and Battery Storage Systems in Strata Apartments

“…Distribution of energy among apartment and CP loads from shared PV-BESS still requires research. Shared PV and BESS has been installed in apartments [16] where metered CP load provides a much better understanding of the diurnal and monthly electricity usage. Although CP usage as a rule of thumb can be billed equally among the residents, equitable allocation of CP load demand with the majority of load met by renewable sources is still a challenging issue.…”

“…Generally, the shared microgrid consists of a centralized BESS, PV source, and metering network connected to the apartment loads [4,16,54]. This also includes the CP load, which forms an integral part of the shared network.…”

“…Usually, there are two types of PV-BESS configurations in residential applications, Alternating current (AC) coupled and Direct current (DC) coupled. In this study, Evermore and Gen Y implemented AC-coupled systems, whereas SHAC installed DC-coupled systems [16].…”

“…Usually, there are two types of PV-BESS configurations in residential applications, Alternating current (AC) coupled and Direct current (DC) coupled. In this study, Evermore and Gen Y implemented AC-coupled systems, whereas SHAC installed DC-coupled systems [16]. The primary rationale for selecting these configurations are based on the following particular preferences: (1) Storing PV generation in batteries; (2) covering apartment load demand according to available PV-BESS capacity; (3) export excess generation to the local aggregator for implementation of energy trading and allocation; and (4) export the remaining surplus to the utility.…”

“…The connection schematic in Figure 2a shows individual apartment load connected and metered separately alongside common property load, and this is often termed a Shared Energy Microgrid [16] and embedded network [20]. As indicated earlier, the AC-coupled system links to the AC bus via the bidirectional DC-AC inverter and DC-DC converter.…”