The Meridian Energy partial privatisation is so large it may have to be split in two, Prime Minister John Key says.

The 113,000 so called "mum and dad" investors who bought Mighty River shares included companies, trusts and investment institutions, Treasury has confirmed.

Not much time has passed since the Government's Budget announcement that shares in Meridian Energy would be the next to be sold.

The Green Party says that shares sold in the recent float of Mighty River Power went to only a small group of investors - and claims of widespread 'mum and dad' ownership are false.

What the assets are worth now depends on the future path of electricity prices and the effect that has on the company's cashflows, writes Brian Fallow.

The Government will have to bump up the sweeteners to get enough mum and dad investors to buy into Meridian Energy, an analyst says.

The Government will waste no time selling down Meridian Energy with Treasury officials expected to meet investment bankers on Monday.

Meridian Energy, New Zealand's biggest and most profitable power company, will be partially privatised later this year, Finance Minister Bill English confirmed in yesterday's Budget.

Editorial: Naturally enough, the Government was keen to put the entire blame for what happened on "politicking" by Labour and the Greens.

If Meridian Energy had already floated, it's a fair bet that its share price would have dropped after the Opposition unveiled its electricity policy a week ago.

Crucial face-to-face talks between the owners of the Tiwai Point aluminium smelter and Meridian Energy resume in Wellington today, and could take the rest of the week.

At 10 o'clock in the morning it is briefly quiet inside the Northland house which is also a small power station.

The Government has set a price range of $2.35 to $2.80 per share for the partial privatisation of Mighty River Power.

Prospects of keeping the Tiwai Pt aluminium smelter open in the long-term are grim, with Meridian Energy saying it is still in the dark.

Contact's share price dropped this morning, partly in response to uncertainty over the future of the Tiwai Point aluminium smelter.

The Tiwai Pt power price stoush will probably have a small negative effect on the price of Mighty River - but it's not a showstopper say sharemarket analysts.

The Government has opened discussions with Tiwai Point aluminium smelter's ultimate owners Rio Tinto in a bid to broker a deal after talks between the smelter and Meridian Energy reportedly broke down.

Tiwai Pt aluminium smelter's owners have contradicted a report from Meridian, saying they think a power deal can be agreed on.

Potential investors in Mighty River Power, Genesis Energy and Meridian will be exposed to the financial impacts caused by any new charges linked to water or geothermal use and land resumption.

The state-owned electricity generator and retailer yesterday reported an underlying net profit after tax of $88 million for the latest half-year after non-cash items

Meridian Energy says it's ready for partial privatisation and expects a significant uplift in operating earnings after transmission outages knocked its performance.

It is folly to press on with the partial privatisation of the state-owned power companies when the future of the Tiwai Pt aluminium smelter is unresolved, writes Brian Fallow.