It seems we jumped the gun when we called the SolarImpact the world's first ocean-going solar yacht based just off its CAD renders. There's another company out there with boats in the water, and the Silent 55 can cruise for up to 100 miles (160 km) per day for weeks at a time on solar power alone.

Its 30 high-efficiency photovoltaic panels deliver a peak around 10 kilowatts into a 15 kVa inverter and a battery of unspecified size. That's not exactly a ton of solar power, really, considering that this thing can be specified in an "E-Power" configuration with 2 x 135 kW motors, or a "cruiser" version with 2 x 30-kW motors.

But Silent Yachts CEO Michael Köhler says it's enough to give the Silent 55 "the ability to cruise for many hours at normal speed and throughout the entire day and evening at reduced speed."

Clearly, you'll need to be very frugal with your use of throttles, appliances and whatnot if you want to go very far, but the Silent 55 also comes prepared to get a little noisy with a diesel generator capable of kicking in up to 100 kW.

If burning dinosaur bones ain't your style – and we'd assume it's not – you can specify it to include a mast and sails, or even a "sky sail" – a parachute-like kite that deploys up to 150 meters (490 ft) high, taking advantages of higher altitude winds that are up to 25 times stronger, without throwing any shade on the solar panels.

The rest of the yacht looks nice enough. The top deck is dominated by solar panels, understandably enough, while the main deck gives you a little more room to lounge about and soak up some sun for yourself, and the interior offers a decent sized 40-m² (430-ft2) living space. As for sleeping quarters, you can specify it in a number of different patterns, including one that puts nice, spacious double bedrooms at the front, left and right, sitting above the waterline and each with its own bathroom.

Down below, things get a lot less glamorous, but hopefully you won't have to spend much time down there anyway, as the electric powertrain is all but maintenance-free.

The price? The Silent 55 starts at €1.4 million (US$1.6 million), which isn't too bad for this kind of vessel, given that your fuel and maintenance bills will be going way down. The boat's party potential definitely drops with the solar panels soaking up sun your guests might otherwise prefer to themselves but, on the other hand, if you're going to do this kind of thing, this is one of the less wasteful and more practical ways you can go about it. And if you need to go bigger, Silent Yachts is working on 64- and 79-ft (19.5- and 24-m) versions that crank things up a level, both in space and luxury.

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