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The number of residential consumers with solar PV and batteries, aka prosumers, has been increasing in recent years. Incentives now exist for prosumers to operate their batteries in more profitable ways than self-consumption mode. However, this can increase prosumer exports or imports, resulting in power flows that can lead to voltage and thermal limit violations in distribution networks. This work proposes a framework for Distribution Network Operators (DNOs) to ensure the integrity of MV-LV networks by using dynamic operating limits for prosumers. Periodically, individual prosumers send their intended operation (net exports/imports) as determined by their local control to the DNO who then assesses network integrity using smart meter data and a power flow engine. If a potential violation is detected, their maximum operating limits are determined based on a three-phase optimal power flow that incorporates network constraints and fairness aspects. A real Australian MV feeder with realistically modelled LV networks and 4,500+ households is studied, where prosumers’ local controls operate based on energy prices. Time-series results demonstrate that the proposed framework can help DNOs ensure network integrity and fairness across prosumers. Furthermore, it unlocks larger profitability for prosumers compared with the use the 5kW fixed export limit adopted in Australia. [ABSTRACT FROM AUTHOR]

The rapid adoption of residential-scale photovoltaic (PV) systems in low-voltage (LV) networks combined with the falling prices of residential-scale battery energy storage (BES) systems is paving the way for a future in which customers could locally supply most of their energy needs. However, off-the-shelf (OTS) storage systems operate for the sole benefit of the customer (reducing grid imports). This means that charging might not occur during times of high PV generation, resulting in technical issues on LV and medium-voltage (MV) networks. This paper proposes an adaptive decentralized control strategy for residential-scale BES systems to reduce voltage and thermal issues whilst still benefiting customers. With this strategy, the power charging and discharging rates constantly adapt throughout the day based on clear-sky irradiance, PV generation, demand, and state of charge; significantly reducing reverse power flows and ensuring adequate storage capacity the next morning. A real Australian MV feeder with realistically modeled LV networks is studied using smart meter data. Results demonstrate that the proposed control strategy overcomes the limitations of the OTS BES. It is also shown that it can be as effective as an ideal optimization-based approach, being able to manage all technical issues without significantly affecting customers. [ABSTRACT FROM AUTHOR]

• Excess power from solar PV reduces aggregated net demand and causes the 'duck curve'. • Off-the-shelf batteries can reduce excess PV generation, but the extent is unknown. • Realistic bottom-up modeling provides more accurate aggregated net demands. • Commercially available off-the-shelf batteries still lead to 'duck curve' effects. • Adopting smart battery controllers can provide opportunities for long-term benefits. The declining cost of residential battery energy storage (BES) and photovoltaic (PV) systems enable customers to significantly reduce their energy dependency from the grid. By absorbing excess PV generation, BES systems could reduce impacts associated with the 'duck curve'. However, since off-the-shelf (OTS) BES systems are controlled for customer benefits, this absorption might be limited at times, resulting in similar duck curve effects. This work proposes a bottom-up modeling approach to demonstrate the system-level generation cost effects from residential BES systems. Using a modified IEEE 9-bus system with real anonymized smart meter data, results show that with the OTS BES control, the overall reduction in system net demand due to peak PV generation still occurs which leads to baseload generation shutting off, incurring additional costs. Alternatively, the adoption of smarter BES controls aimed at mitigating impacts on distribution networks by reducing PV exports can bring significant system-level generation cost reductions. [ABSTRACT FROM AUTHOR]