Verve Energy has been forced to deny rampant industry speculation that faulty concrete wind turbine tower foundations at its troubled Mumbida green power project were responsible for a six-month delay and cost blowouts on the $130 million venture.
To ensure stability in high winds, concrete strength at the base of wind towers usually ranges from 30 to 45 Newtons per square millimetre according to analysts.
However, multiple sources have suggested to WestBusiness that the measure got as low as 18 to 20 N/mm2 on some footings at Mumbida, which is being built by construction giant Leighton Contractors.
Leighton faces a multimillion-dollar damages claim from Verve and its joint venture partner Infrastructure Capital Group over the construction-related delays.
The construction giant referred questions over the concrete foundations to project operator Verve, which denied the claims.
“All completed aspects of the Mumbida Wind Farm project have been undertaken within approved engineering standards,” a Verve spokesman said.
But the exact nature of the delay has never been detailed, with Verve arguing that commercial confidentiality precludes it from revealing too much information.
The 55-megawatt farm near Geraldton, using Australian-first General Electric turbines and initially developed by Macquarie Group, was meant to be operational in November but has only started full commissioning of its 22 turbines.
The delay has also cost the joint venture partners millions in lost so-called capacity payments from not having the plant ready to provide electricity over last summer.
Verve said the last turbine went “live” on April 9, meaning the project should be ready for this year’s peak summer power period.
Shadow energy minister Bill Johnston said that, along with Verve’s bungled $250 million revival of its ageing Muja AB coal-fired power station, the commercial joint-venture structure was not a good one for taxpayers.
“These joint venture structures are very bad for the people of WA because they hide the truth about what is going on,” Mr Johnston said.
“We saw that with Muja where the minister as late as last as October said that there were no problems with Muja when in fact everybody knew it was a shambles.
“They are also an artificial device to hide borrowings by the Government.
“The Government can’t hide away from these entities because State Government’s can’t run away.
“But they are not consolidating that debt into the official debt figures because they say they are only (providing) equity in the private entity and not the project itself.”