WA’s Synergy says fossil fuel generators not coping with rooftop solar boom

Western Australia’s government-owned utility Synergy says it was forced to take one of its newest fossil fuel generators offline for extended repairs, after changes to an increasingly solar-heavy network took their toll on the plant.

In what he described as a “duty-related issue,” Synergy chief Jason Waters said constant “starts and stops” caused by an influx of solar panels on the south-west grid had disrupted operations at the 240MW gas-fired Cockburn power station.

Waters said the changes in the way consumers used the grid, which were being shaped by the state-wide shift to rooftop solar, had made it hard for conventional plants to run according to their design.

Synergy has seven power stations spaced along WA’s South West Interconnected System (SWIS), five of which are classed as major power stations – Cockburn included.

Meanwhile, more than 160MW of distributed solar PV has been added to Synergy’s grid over the 2017/18 financial year alone, taking its total to more than 1,000MW.

“Cockburn is probably one of our newest plants,” Waters told an Upper House Parliamentary hearing about the combined-cycle plant.

“(Given) the amount of starts and stops Cockburn has been required to undertake due to the changes in the way system demand takes place, the amount of rooftop solar and other factors, we did identify an issue with Cockburn that required an extended outage to sort out.”

The utility touched on the impact of these changes in its annual report in September, noting that total generation had fallen by 10 per cent in the last financial year, and electricity sales by 5.6 per cent.

As Giles Parkinson noted at the time, the utility doesn’t seem too pleased about this, although it appears to concede the transition to cheaper renewables is inevitable.

“In our state, like elsewhere, this profound change is driven by a number of simultaneous forces,” chairman Robert Cole, the former head of oil and gas producer Beach Petroleum, said in notes on the annual report.

“The uptake of rooftop PV has resulted in a challenging daily load profile, and the increasing levels of intermittent large-scale renewables have impacted the critical stabilising role of traditional generation.”

But Waters reportedly conceded that there was little sign of demand for rooftop solar slowing, and said Synergy was confident this, as well as large-scale renewable additions to the grid, would not compromise its operations.