Batteries and grid upgrades deliver better ratings and revenue for blighted wind and solar farms

A host of wind and solar projects in the south-west of New South Wales and north-west Victoria have received good news after the latest annual grid ratings point to a likely boost in revenues for the coming year.

More than a dozen wind and solar projects – in and around a part of the grid that became known as the “Rhombus of Regret” – have been given a significant boost in so-called marginal loss factors for the coming year, which should translate into a lift in revenue.

The marginal loss factor relates to the AEMO assessment on electricity losses on the grid, and can be affected by congestion and limited grid capacity. A rating of 1.0 means that all a project’s output is credited as delivered, and therefore earn revenue, but a rating of 0.75 means that a quarter of its output is effectively lost.

Two of the worst affected wind and solar projects – the Broken Hill solar farm and the nearby Silverton wind farm – have been advised of some of biggest improvements in the MLF, under draft numbers released by the Australian Energy Market Operator, with Broken Hill to leap to a new rating of 94.5 from 77.8, and Silverton jumping to 90.5 from 80.5.

Both are being helped by the commissioning of the new Broken Hill big battery, which can store excess output that can’t otherwise be sent down the single transmission line to the rest of the grid.

But solar projects elsewhere in the south-west are also benefitting, with Limondale’s MLF leaping to 89.6 from 77.6, and other solar farms such as Colleambally, Darlington, Hillston, Junee, Sebastopol, Walla Walla and Wyalong also enjoying substantial increases.

Other projects located in the “rhombus of regret” also have cause for celebrations, with MLF increases of more than five per cent for the likes of the Cohuna, Gannawarra, Kiamal, Wemen and Yatpool solar farms.

All these projects are benefiting from grid upgrades and the increased amount of battery storage. They are also expected to benefit from the imminent commissioning of the first 150 MW stage of the Project Energy Connect link from South Australia to NSW, which is in the throes of its final hold point testing.

In Queensland, the Clare, Whitsunday and Kidston solar farms have also been given a boost, thanks to the increase in battery storage.

Ironically, however, some solar projects increase in MLFs is at least partially due to the increased amount of economic, or voluntary curtailment as a result of negative wholesale prices in the middle of the day, when some project owners choose to switch off their output rather than pay another party to take their solar.

“Large increases in MLF outcomes in north-west Victoria (are) primarily driven by an increase in local storage and economic curtailment,” the draft AEMO report says. The new numbers are calculated on historical curtailment figures for the region.

But it is not good news everywhere, with some wind and solar projects in other regions badly affected by changed in grid flows, particularly between different states.

In the north of NSW, several projects such as the Sapphire wind farm and the New England solar farms (the biggest solar project in the country) have suffered because of increased flows and competition from Queensland as a result of a recent grid upgrade.

In South Australia, a similar penalty has been imposed on projects in the south-east, with the Lake Bonney and Cabinda wind farms the worst affected, and the Tailem Bend solar farms and big battery also affected.

AEMO says this is the result of increased competition from Victoria. But most other projects in the state had small agains.

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