Mercury Energy has lifted its net profit by 159 percent in the June year to $290 million.
The company’s earnings before interest, tax, depreciation, amortisation and financial instruments came to $877m, up 4 percent on the previous year.
Mercury CEO Vince Hawksworth has pushed back against accusations of profiteering from Minister Shane Jones.
"If you look at today's result, and yes, it was a very good result - on the back of quite a bit of new investment in our business."
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