Mr Cumming, who was mentioned in the Senate last month as being   the victim of alleged death threats, arson attacks and discrediting of his engineering credentials, told The Standard yesterday he was not deterred.

“If I’m wrong, say I’m wrong and prove it,”  he said.

“I believe energy companies are trying to mask what they are doing with figures for wind farms and coal-burning power stations.

“Recent reports from Ireland and The Netherlands show wind farms claim two to three times what they are abating. 

“I believe companies are using reverse calculations of their figures.”

His claims were again dismissed by the Clean Energy Council of Australia (CECA), which represents most wind farm companies operating in the south-west.

“He is  demonstrably wrong,” CECA media manager Mark Bretherton said.

Mr Cumming has been a long-time opponent of  the Mortlake wind farm project and claimed sensitive brolga population data had been deliberately omitted from the Atlas of Victorian Wildlife.

He maintains wind farms are an ineffective way of reducing greenhouse emissions.

Senator Chris Back told the Senate on October 30 that Mr Cumming had been heavily criticised after being quoted in The Australian newspaper on September 1.

CECA policy director Russell Marsh replied to the newspaper by describing Mr Cumming as “an activist who is not a mechanical engineer” and his claims as “amateur analysis riddled with errors and incorrect assumptions”.

Mr Cumming said he was still awaiting an apology he had sought from Mr Marsh. 

He is also still seeking answers from the Clean Energy Regulator to his question: are wind developments actually reducing greenhouse gas emissions?

“I defend my credentials. I’ve worked all around the world as an engineer,” Mr Cumming said.