Ergon Energy is set to be the first utility in Australia to deploy grid-scale storage with the rollout of 20 Grid Utility Support Systems (GUSS) to help power sections of its rural electricity network by mid-2015.
The GUSS storage and control solution has been under development by Ergon Energy since 2006. The tender for the supply of the 20 units was awarded to S&C Electric Company.
GUSS storage solution
The GUSS comprises 50 lithium-ion type batteries providing 25kVA and 100kWh nominal capacity, together with an inverter and control and switchboard.
These items are skid-mounted in a unit 5.3m in length, 1.2m wide and 1.9m in height, and weighing 3.5 tonnes.
The batteries are charged during the night, when electricity use is at its lowest, and discharged during the day when peak is required.
Ergon Energy will be deploying the GUSS units to improve the quality and reliability of electricity supply on its high voltage Single Wire Earth Return (SWER) distribution networks. These have proven to be a low cost and reliable way of servicing low customer densities in rural and remote communities throughout the state. However, increasing electricity demand as customers’ lifestyles have improved is placing strain on the capacity these networks can deliver during peak times.
GUSS on constrained networks
“Traditional augmentation solutions to constrained SWER lines where demand on that line is exceeding its capabilities can cost in excess of [Au]$2 million,” Ergon chief executive Ian McLeod explained. “GUSS units are not only a quicker solution than traditional network augmentation, but the money we can save will ultimately put downward pressure on electricity prices.”
Ergon Energy estimates that the GUSS units could reduce SWER network augmentation costs by more than 35% on current estimates.
Additionally, customers on constrained networks who have had to limit their demand due to the available capacity may be able to access additional supply.
Ergon Energy operates around 65,000km of SWER network serving more than 26,000 customers.
The 20 GUSS units will be deployed on 12 of the SWER systems. The company expects that it could be deploying many hundreds of units across the SWER network in coming years.
The units will also help Ergon's network interact with customer solar PV installations more effectively and help avoid costly issues which are sometimes created by exported power from rooftop solar.