Genesis Energy says it's doing what it can to ensure Huntly Power Station helps the country avoid another generation shortfall this winter.  

More than 500,000 tonnes of coal was restocked earlier this month, with another 500,000 tonnes on the way before September, in anticipation of demand.  

Genesis Chief Executive Malcolm Johns told Andrew Dickens Huntly's units ran at full capacity last winter, working their way through 800,000 tonnes of coal. 

He says a million tonnes is about appropriate for what he believes can be put through the machines. 

Johns says this kind of preparation will still be needed in the future, even with 95% renewable generation in New Zealand in 2035.  

He says 100% renewable can't genuinely be reached, and back up is needed for when the rain doesn't come and the wind doesn't blow. 

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