Transgrid finalises system strength plan

Transgrid says it has finalised its system strength plan for New South Wales, defining solutions it will use to maintain grid stability as the state transitions away from coal-fired power generation.

The company says that grid-forming batteries and synchronous condensers will underpin “an innovative portfolio of solutions designed to bolster the strength or ‘heartbeat’ of the NSW power system so that it can more rapidly accommodate renewable energy generation”.

Transgrid says it selected the solutions after assessing more than 100 individual solutions over a three-year process.

“The NSW grid has traditionally relied upon coal generators to provide system strength as a by-product of their typical operation,” said Transgrid Acting Executive General Manager of Network Jason Krstanoski. “There is now an urgent need to maintain this heartbeat, as we accelerate the transition to wind and solar and as 80% of the coal capacity in NSW retires in the next decade.

“This portfolio of system strength solutions is vital to enable the NSW power system to accelerate the transition to 100% instantaneous renewables, unlocking renewable generation that would otherwise be constrained.”

Transgrid this week published its Project Assessment Conclusions Report (PACR), the final step in a three-stage regulatory process to ensure the best outcome for the market and consumers.

The report identifies a preferred portfolio of system strength solutions, including:

• 10 synchronous condensers on Transgrid’s backbone network — machines specifically designed to support system strength, inertia and system voltage;
• 5 GW of grid-forming batteries, providing the equivalent strength to another 17 synchronous condensers;
• modifications to 650 MW of synchronous generators to enable synchronous condenser-mode;
• operation of synchronous generators to fill gaps in system strength where required;
• additional targeted solutions to support new renewables within the New England and Hunter-Central Coast Renewable Energy Zones.
   

“Our preferred portfolio utilises innovative grid-forming batteries to provide almost half of NSW’s system strength requirements, with synchronous condensers providing the other half,” Krstanoski said. “Together, these solutions are expected to deliver $8.8 billion in net market benefits by ensuring the safe and reliable operation of the grid and accelerating the transition to more affordable, cleaner renewable energy.

“The report also demonstrates that additional net market benefits of $1.2 billion could be delivered if Transgrid accelerates deployment of synchronous condensers, so we are currently investigating options to fast-track the project.”

Image: Supplied.