Analysts believe the forthcoming sale of part of Meridian Energy will bring the Government $400 - $700 million more than it got from the float of Mighty River Power.
Meridian posted positive financial news on Monday and a partial sale is expected in October.
The company's earnings before interest, taxation and other costs were $584 million.
Analysts use price-to-earnings ratios for other energy companies such as Mighty River Power and Contact Energy, to work out what Meridian would be worth to investors.
They have valued the 49% share the Government is floating at between $2.1 - $2.4 billion.
So far, the Government privatisation programme has earned $1.7 billion, from selling part of Mighty River Power.