A. Narimani

Storage optimum placement in distribution system including renewable energy resources

The inclusion of bulk Electric Energy Storages (EES) in distribution system offers a number of benefits to utilities to improve reliability and efficiency of the network. However high investment costs of EES installation should be justified for the utilities. Benefits such as system upgrade postponement and cost of energy purchased reduction in the network as well as reliability and efficiency improvement have made utilities persuaded to afford storage investment and maintenance costs. In this regard, optimal sizing and siting of storages has become the focus of the recent researches to provide a tradeoff between investment costs and expected benefits from storages. In this context, this paper proposes a strategy to optimize the size of EESs in the network while minimizing the cost of purchased energy and investment/maintenance cost of the storage. A case study is presented to evaluate this approach and examine the results.

Impact of PV units in LV feeders on distribution system reliability

Re-supplying loads on outage through cross-connect from adjacent feeders in a distribution system may cause voltage drop and hence require load shedding. However, the surplus PV generated in some of the LV feeders can prevent load shedding, and improve reliability. In order to measure these effects, this paper proposes the application of Direct Load Flow method[1] in reliability evaluation of distribution systems with PV units. As part of this study, seasonal impacts on load consumption together with surplus PV output power injection to higher voltage networks are also considered. New indices are proposed to measure yearly expected energy export, from LV to MV and from MV to higher voltage network.

SAIDI constrained economic planning and utilization of central storage in rural distribution networks

This paper forms a framework for allocating a central electric energy storage (EES) in discrete communities, forming as segmentations along the rural feeders, where the installation of cross connects are not economic or even feasible. In this framework, EESs that centrally can be installed in each community are owned and operated by an aggregator/retailer, trading bidirectional energy transactions with both the grid and the customers. The objective is to find optimum investment in storage capacity in rural feeders for minimum annual energy purchase cost using energy arbitrage opportunities, while maintaining an allowable level of system average interruption duration index (SAIDI). As a part of EES sizing and siting optimization in this approach, annual hourly network data are utilized for charge/discharge scheduling and constraint, and for system reliability assessment—using the k-means clustering technique. This method is applied to a rural network in Queensland, Australia, and the results are examined to show the effectiveness of this method.

Value of concentrated solar power with thermal energy storage in the national electricity market of Australia

The concentrated solar power (CSP) with thermal energy storage (TES) is considered as one of the promising renewable technologies for achieving Australias renewable energy targets. The dispatchability of CSP plants with TES can provide grid flexibility by shifting energy over the time. In this paper the ability of TES to improve the value of CSP plants is examined by production cost simulation (PCS) of the NEM using PLEXOS software. The impacts of variations in the size of solar field (i.e. solar multiple-SM) and the size of TES on the operation benefit of CSP plant are also examined.