Luxury carmakers are showing increasing interest in hybrid powertrains, but what about makers of luxury boats?

A large yacht can consume 130 gallons of fuel per hour just while idling, so there's clearly room for improvement there.

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That may be why one company decided to build a yacht to show that vessels can be green even if they require a lot of, err, green to obtain.

Dutch yacht builder Feadship recently launched the Savannah, a 273-foot exercise in opulence that uses both diesel and electric power.

Savannah hybrid mega-yacht

Savannah hybrid mega-yacht

Three generators and a massive lithium-ion battery pack allowed designers to install one diesel engine--instead of the normal two--yielding performance similar to other mega-yachts, but with increased fuel efficiency, according to CNBC.

That, along with a sleeker hull design featuring a very thin bow, allows the Savannah to achieve 30 percent greater fuel efficiency than comparably-sized yachts, according to Feadship.

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Like a hybrid car, the Savannah can operate solely on either electric or internal-combustion power, or a combination of the two.

It can get by on electric power only for shorter trips, and use diesel for longer hauls, but maximum performance requires using both power sources.

In hybrid mode, the Savannah's estimated top speed is 19 knots, or just under 22 mph.

Savannah hybrid mega-yacht

Savannah hybrid mega-yacht

There are also some features you won't find in anything short of a mega-yacht.

The craft features an "underwater lounge" that allows people to view fish swimming along outside the hull, or see the underside of the 29-foot swimming pool.

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All of this reportedly took four years to design and build, with a workforce of 1,000 people. The finished ship has a crew of 26.

Feadship won't disclose exactly how much this hybrid mega-yacht cost, but it's reportedly already been sold to a European buyer.


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