Strung along

Broken Hill's renewable generators proved useless when put to the test

The Silverton Wind Farm and Broken Hill Solar plant were supposed to produce enough electricity to power 117,000 homes. They are supported by AGL's 50 MWh battery facility at Pinnacles Place, one of the largest in Australia.

Yet Broken Hill, population 19,000, has been in a semi-permanent state of blackout since a storm brought down the transmission line connecting the town to the East Coast grid.

Broken Hill's plight exposes the gap between the promise of renewable energy and what it delivers.

AGL claimed its battery would ensure a reliable electricity supply to the town if the transmission lines went down. The combination of wind, solar, and storage would allow Broken Hill to operate on a renewable microgrid until its connection to the outside world was restored.

Yet the battery wasn't switched on until last Friday (October 25), eight days after the city was disconnected from the East Coast grid when transmission towers collapsed in a storm.  Diesel generators are being used to recharge it because the wind and solar generators were also decoupled from the system.

Rooftop solar power is still produced but its intermittency is affecting the local grid's stability. Essential Energy, which supplies power to Broken Hill, has asked customers to turn off their solar supply main switch to prevent the 40-year-old backup gas turbine generator from tripping.

Chris Bowen contends that renewable energy is the cheapest and most reliable source of carbon-free electricity. He acts on the assumption that wind and solar supported by batteries can substitute for coal.

Yet Broken Hill's experience shows how crucial baseload generation is to the grid's stability. Without it, balancing supply and demand becomes impossible, even with the grid-forming inverters attached to the Broken Hill battery at federal taxpayer’s expensive.

In summary, approximately $650 million worth of renewable energy investment within a 25 km radius of Broken Hill has proved to be useless when put the test. The technical challenges of operating a grid on renewable energy alone appear insurmountable using the current technology, even on a small scale.

If wind, solar and storage can’t keep the beer cold in a small city like Broken Hill, how will it perform when called upon to power the rest of the country?

www.realitybites.tvBroken Hill’s experience should serve as a cautionary tale for the incoming Liberal National Party government in Queensland as it assesses the energy policy mess left by Labor. Among the expensive proposals on the books is Copper String, a 1100 km high-voltage transmission line from Townsville to Mount Isa crossing the remote and rugged terrain of North Queensland. Mount Isa operates on a micro-grid served by two gas-fired power stations with diesel generators used as a backup. Replacing locally-generated power by linking Mount Isa to the National Energy Market is costly and introduces the risk of transmission failure. The latest estimate for Copper String, which would be funded entirely by the government, is $5 billion, but the cost of building transmission lines is escalating dramatically.

David Crisafulli has every reason to put the project on hold while other options are considered. One solution could be micro modular reactors—self-contained, mass-produced nuclear power plants that are relatively easy to transport and install close to where the electricity is needed. This is the preferred option in Canada where MMR’s are seen as breakthough for remote indigenous communities and mining operations.

Bowen's claims about the cost of renewable energy were called into question last week when senior executives from the Australian Electricity Market Operator gave evidence under oath to a Senate select committee.

AEMO's assertion that its blueprint for the transition to renewables was "the lowest cost pathway" is misleading. AEMO's CEO, Daniel Westerman, told the committee that its modeling only considered the wholesale cost of electricity. AEMO did not model network costs, transmission and distribution costs, or retailer margins.

“A home electricity bill will need to consider all of those factors,” he said.

Senator Matt Canavan asked: "You're saying you cannot guarantee that the current government policy settings you model will deliver lower power prices? "

Westerman replied: “I can't guarantee that. No.” He said AEMO “explicitly doesn't consider other parts of the consumer energy bill.”

Westerman was asked if AEMO had costed other policy options before concluding that the cheapest path was renewable energy backed by storage and gas.

No, said Westerman. “It is the role of policy makers to identify alternatives and make those public policy decisions.

"If policy makers wanted to ask AEMO for advice, we would be pleased to provide it. But it's not really our role to judge on whether it's a good policy or not."

Canavan asked: "So that and so there's no analysis of whether that's a good idea or not."

“No. Sorry. We don't analyse that,” replied Merryn York, AEMO’s Executive General Manager, System Design.

In summary, AEMO’s “least cost pathway” turns out to be the wholesale cost of a transition to renewable energy on the accelerated timetable stipulated by the government.

The destination of this energy plan is not cheaper electricity or cleaner energy in the way most people would expect. Instead, AEMO's lowest-cost pathway aims to meet Labor’s political target of 82% carbon-free electricity by 2030 and 100% renewable power by 2050, using mostly wind, solar, and some gas. AEMO's model excludes any consideration of nuclear energy—one of the few reliable, low-emission baseload options available.

It is alarming that AEMO has not even attempted to model the retail cost of electricity. AEMO's Integrated Systems Plan is the blueprint for the government's energy transition. It sets the deadline for phasing out coal generation by 2038, a fourfold increase in rooftop solar, a sixfold increase in grid-scale wind and solar, and a 13-fold increase in battery storage.

Yet, AEMO doesn’t consider it part of its brief to estimate how much this will cost or the impact on retail energy prices. Nor does AEMO attempt to vouch for the technical feasibility of its plan. Engineering, like economic modelling, is not part of its job.