Genesis Energy is worried that paying the full environmental cost of generating electricity in their dirty, inefficient coal-fired power station at Huntly could drive them out of the market. Good. That is, after all, the point. Making generators pay for their emissions is explicitly intended to push the market towards cleaner and more sustainable forms of generation, and away from dinosaur plants like Huntly - and if Genesis want to stay in business, they'd be wise to start broadening their generation portfolio.
Unfortunately, Genesis seems committed to thermal generation - 75% of their capacity is thermal (50% coal), and their new investments are focused on large scale gas generation rather than wind. So rather than dragging themselves into the 21st century, they've decided to follow the traditional path of New Zealand business, and whine to the government for special treatment. And in typical fashion, they are doing this by complaining that others might be receiving special treatment:
[Malcolm Alexander, general manager of corporate affairs] does not want to see any sweetheart deals that will allow companies to reap profits at the expense of others.
But what is being proposed is not any sort of "sweetheart deal". All generators will face the cost of carbon, and all will have to pay for their emissions. And this is being done precisely to stop companies reaping profits at the expense of others - namely, ordinary taxpayers, who currently effectively subsidise electricity emissions to the tune of $114 million a year.
If Genesis really opposed "sweetheart deals", they'd support emissions trading, and further oppose the grandparenting of emissions permits. Because I can't think of a bigger "sweetheart deal" than that.