Strong growth in Australia’s electricity demand is resulting in increasing numbers of constrained network distribution areas. While the traditional solution has been to build additional generation, transmission and distribution infrastructure, there is increasing interest in solving these problems from the demand side. Such solutions include the use of distributed renewable energy systems, cogeneration and load (demand) response schemes.

Despite substantial correlation between electricity demand and photovoltaic power generation, the intermittency of renewable sources mean that they cannot be relied upon and as such do not ameliorate the need for network augmentation. This was investigated in detail for the Kogarah Town Square 160kW photovoltaic system.

CSIRO’s Virtual Power Station (VPS) allows multiple geographically disperse photovoltaic sites to present to the electricity network as a single reliable dispatchable entity. We have deployed a research scale VPS system based at the CSIRO Energy Centre in Newcastle, Australia - currently consisting of eight sites, linked through a high speed (internet based) communications network. Two of the sites include battery storage, allowing the aggregate system output power to be reliably controlled (within 5% of an agreed output) in spite of the intermittency of the photovoltaic sources.

Our research is developing algorithms to mesh geospatial information with weather and individual site performance data to improve generation forecasting and reliability. Improved forecasting allows energy storage requirements to be minimised, thus reducing system cost whilst achieving the reliability needed to allow deferral of network augmentation costs. These strengthen the economic case for the widespread deployment of photovoltaic systems.