WELLINGTON – New Zealand’s government expects to raise up to $1.8 billion by selling nearly half of the country’s largest power company.

Documents filed Friday show the government expects to raise between 1.9 and 2.2 billion New Zealand dollars ($1.6 billion-$1.8 billion) by selling 49 percent of state-owned Meridian Energy.

The share offer is the centerpiece of a contentious government asset sales policy. The center-right government says the proceeds will help reduce New Zealand’s public debt and pay for hospitals, schools and roads.

Opponents have likened the program to selling the family silver.

The government hopes to raise at least NZ$5 billion ($4.2 billion) from asset sales.

Under the Meridian offer, buyers will need to pay NZ$1 initially for shares and then pay a second installment of between NZ$0.50 and NZ$0.80 after 18 months. New Zealand mom-and-pop retail investors are guaranteed a price not over NZ$1.60 per share, while institutional investors may end up paying more.

Meridian generates about 30 percent of New Zealand’s electricity from hydro dams and wind farms.

The final price will be announced Oct. 23, and Meridian is scheduled to begin trading on the New Zealand and Australian stock exchanges on Oct. 29.

The initial public offering will likely make Meridian the most valuable company on the New Zealand stock market, with a capitalization of up to NZ$4.4 billion ($3.7 billion). The government will keep control of Meridian through its 51 percent stake.

The government in May raised NZ$1.7 billion ($1.4 billion) by selling 49 percent of another power company, Mighty River Power, but the performance of its shares has so far disappointed many small investors. The stock was trading at NZ$2.22 ($1.86) Friday, more than 10 percent below its IPO price of NZ$2.50 ($3), despite the broader market reaching all-time highs this week.

The Meridian IPO valuation is considerably less than a government valuation last year that put the company’s worth at NZ$6.6 billion ($5.5 billion).

Part of the reduction is due to uncertainty surrounding the future of an aluminum plant majority-owned by Rio Tinto, which is Meridian’s single biggest customer. Also hurting the value are new policies announced by opposition political parties that will increase government control of the electricity market and force down residential electricity prices.

“It would be nice to be getting (NZ$) 10 billion ($8.3 billion), wouldn’t it, because we have a lot of infrastructure demands,” said Finance Minister Bill English on Friday, adding that “The value is what is.”

Opponents said the low price highlights the program’s failure.

“This is a fire sale, pure and simple,” said opposition lawmaker Clayton Cosgrove in a statement issued to the press.

The program has proved contentious, and opponents recently gathered more than 300,000 signatures to force a national referendum on whether people support the sales.

The result of the referendum will likely be only symbolic, however, because the referendum will not be held before the sales are completed, or nearly completed, and won’t compel the government to act.

Meridian isn’t an Apple Inc. or a Microsoft Corp., Chief Executive Officer Mark Binns said in an interview before the announcement. “No one should be perceiving this as a stock that’s going to double or triple in value inside a couple of years. But we’re a solid company performing well and generating very solid cash flows, which we would foresee translating into good dividend yields.”

Meridian owns seven hydro-electric dams and four wind farms in New Zealand, generating about 30 percent of the country’s electricity needs.

It has a wind installation in Australia and another under construction. It is selling a solar plant in California.

With electricity supply in New Zealand outstripping demand, “we’re not going out there trying to sell a growth story,” said Binns, who is scheduling meetings with investors in New Zealand and overseas to promote the IPO.

On Friday the company forecast operating earnings of NZ$548.4 million ($459 million) for the year through June, down 6.2 percent from a year earlier.