The scale and pace of solar and wind farm generation connected electrically in remote areas of the national electricity market is presenting unprecedented technical issues, which are affecting grid performance and operational stability.
That is according to the Australian Energy Market Operator, who in September 2019, identified that interactions involving five West Murray solar farms produced voltage oscillations following a transmission line fault, which exceeded the regulated limits for power system security.
“Since then, AEMO has been working closely with the solar generators, their equipment suppliers and network service providers (Powercor and TransGrid), to conduct testing and help develop a solution that would restore operational compliance,” a statement said.
“This will then enable NSPs (network service providers) and AEMO to move forward with new generation assessments to meet power system security needs.”
There are currently about 1200 MW of committed inverter-based generation projects for the West Murray area and about 3000 MW in the application phase.
“Thermal and stability limits mean it will not be possible for many of these projects to connect or generate at full output ahead of significant investment in network infrastructure,” the AEMO statement said.
The statement said that to significantly reduce new generation limitations in the west Murray area, additional transmission infrastructure was needed.
“As identified in AEMO’s draft 2020 Integrated System Plan, two major inter-connector projects would deliver these benefits for the West Murray area.”
The first project, Project EnergyConnect, will be a new inter-connector between South Australia and NSW, likely to be delivered within the next five years, while the second, VNI West link (formerly Keranglink), is a longer-term project to add an inter-connector between Victoria and NSW.
The Victorian Government said it would continue to push to get upgrades but declined to answer questions about whether solar farms were being approved too quickly.
“We’re leading the country in renewable energy and we need a modern, reliable national grid so Victorians get the full benefit of these investments,” Victorian Energy Minister Lily D'Ambrosio said.
“We’ll continue to push for transmission network upgrades and priorities like KerangLink that will help open up projects in the north-west and provide a vital energy highway between Victoria and NSW.
“At next month’s COAG we’ll continue our fight for better national rules so we can get on with these critical projects.”
State Member for Murray Plains Peter Walsh responded by targeting the government over changes introduced into parliament last week to bypass the critical checks and balances applied by the national energy framework.
“Victorian households will bear the cost of the Andrews Government’s move to go-it-alone on energy projects,” Mr Walsh said.
“Labor has made a mess of Victoria’s energy network, leaving us with an unreliable supply and sending prices skyrocketing.
“Victoria going it alone risks leaving Victorian households with a more unstable and unreliable power supply and even higher bills.”
Edify Energy, who co-owns the Gannawarra Solar Farm, near Kerang, declined to comment on the matter.