FRESH questions have emerged over the state government's report into Western Australia's long-term energy security, and its recommendations to limit the impact of major disruptions to gas supply.
FRESH questions have emerged over the state government's report into Western Australia's long-term energy security, and its recommendations to limit the impact of major disruptions to gas supply.
Energy Minister Peter Collier last week handed down the findings of the Gas Supply and Emergency Management Committee set up in January in the wake of last year's Varanus Island explosion, which crippled WA gas supplies for six months.
The report's key recommendations included retrofitting existing gas-fired power plants to run on diesel when gas is unavailable, and storing up to three months' emergency gas supply in depleted reservoirs close to Perth.
However, the head of one of WA's biggest private electricity suppliers has questioned the report's narrow focus on increased gas storage and greater diesel-fired generation capacity.
Griffin Energy managing director Wayne Trumble said both measures could play an important role in mitigating future disruptions to WA's gas supply.
But he said the report failed to adequately address the state's over-reliance on gas as its primary source of energy for electricity generation. Up to 60 per cent of WA's electricity generation is fuelled by gas.
“I was quite surprised that there was no mention of the need to maintain a diversified portfolio of coal, gas and renewables," Mr Trumble said. "It would seem to me it would be far more economically effective to try and keep some diversity in our fuel supply."
Griffin, which already operates the 400 megawatt Bluewaters coal-fired power station at Collie and the 80MW Emu Downs windfarm at Cervantes, is looking to double its total generating capacity over the next five years.
Mr Trumble noted that, although the Varanus explosion cut WA's gas supplies by a third, those businesses able to switch to alternative fuels were relatively unaffected.
He also noted that a key obstacle to increased supply of renewable energy supplies was the lack of surplus transmission capacity in the state's main electricity grid. That was especially the case in regions best suited to producing large volumes of renewable energy, such as the Mid West.
Industry insiders point to significant practical challenges associated with retrofitting gas-fired plant to also run on diesel and storing enough gas to last a three-month disruption to supplies.
In terms of storage, the report indicated that it would cost only about $50 million a year to store enough gas at the existing Mondarra gas reservoir near Dongara to produce 100 terajoules a day for three months.
However, that would require a six-fold increase in the current capacity of the Mondarra facility and the purchase of up to twice the volume of gas actually required due to the need to maintain reservoir pressure.
Similarly, a supporting consultants study for the committee's report identified the lack of surplus capacity in the road tanker fleet as an obstacle to keeping "dual-fuelled" generators supplied during a crisis. The report noted that the twin-turbine generator at Kemerton would burn 80,000 litres of diesel an hour at full load compared to the 70,000L capacity of typical road tankers.
