Utility estimates it would need between 7.2 cents-to-8.1- cents-per-kilowatt-hour to recover the total cost of the refurbishment.
The $2.4-billion surplus for 2015-16 projected in April by the Tories is now expected to be a $3-billion deficit.
Liberal government wanted impose a $6.6 million to $34.4 million annual royalty.
Premiums expected to fall by 20% for solar and 15% for wind.