Graeme Hart's new $78m yacht launched

New Zealand's richest man has splashed out on a second luxury yacht - this one worth up to an estimated $78 million.

Graeme Hart, reportedly worth around $7 billion, was revealed as the owner of a new expedition super yacht launched in Norway at the weekend.

Norwegian boat builder, Kleven, which usually specialises in oil and fishing industry vessels, launched the 107-metre yacht on Saturday local time, revealing its billionaire owners who were there to watch as it ploughed into the water for the first time.

Mr Hart and wife Robyn were photographed at the shipyard in Ulsteinvik, 570km north of the capital Oslo.

"This is a very exciting project for us. We have been around in the yard and on board the vessel, and I'm very pleased with Kleven and the work that has been done here so far," Mr Hart told business newspaper Dagens Naeringsliv.

He had followed the construction process closely since the contract was awarded last year, he said.

Hundreds of locals turned up to watch the boat launch, the paper reported, taking photographs and videos as it was released.

Both Mr Hart and Kleven would not reveal to the newspaper how much the yacht was worth, but local estimates put it at between 300 million and 400 million Norwegian Krone (between $58 million and $78 million).

However, the monster-sized yacht, which has been named Ulysses, was not built to laze around celebrity ports, the paper said, with Kleven boasting it was built to be "very robust and seaworthy".

It was especially suited to longer expeditions in rough waters, while also being designed for a "luxury" experience. It comes equipped with a helicopter deck, hangar, swimming pool, hot tub, and accommodation for 60 people.

The boatbuilder was hoping this would help it launch into the luxury market.

"The project shows that we can also deliver in this unique market. These are exciting times," Stale Rasmussen, chief executive of Kleven said in a statement.

The ship was designed by Marin Teknikk, which has a long history of working with Kleven.

Ulysses will now undergo its luxury fit-out, with an expected completion date sometime in the spring of 2015.

The owner of the super yacht had been kept under wraps since Kleven announced the contract last year.

It revealed it had been hired to build an expedition support vessel for an international owner, and that the price was "a pretty spectacular sum".

The secret owner had wanted a Norwegian shipbuilder and construction at a Norwegian shipyard because of the "delivery time, quality and price", it said at the time.

Mr Hart shuns the media spotlight, but has grabbed headlines in the past for his luxury yachts.

He previously owned a 58-metre luxury motor yacht, also called Ulysses, which was moored at Auckland's Viaduct for years before being sold, renamed Grand Rusalina and relocated to Monaco.

His 77-metre superyacht Weta is currently in Whangarei reportedly undergoing a $50 million makeover, after sitting for more than a year near Silo Park in Auckland's Wynyard Quarter.

Ulysses luxury features:

* Helipad

* Helicopter hanger

* Swimming pool

* Hot tub

* Sleeps 60 people

* 107 metres long

Super yachts in New Zealand

- Around 50 super yachts come to New Zealand each summer.

- Weta, owned by New Zealand's richest man Graeme Hart, is currently getting repairs done in Whangarei.

- Triple Seven, owned by Alexander Ambramov, who owns a sprawling property in Northland, is set to be berthed on a jetty at his property.

- Imagine, owned by Matteo de Nora, a private donor to Team New Zealand, is moored in Auckland.

- A, owned by Russian fertiliser and chemical magnate Andrey Melnichenko, spent last summer in New Zealand and was the biggest ever to come.

- Secret, built in Germany last year for a mystery owner, arrived in Auckland last month.