Unless your only mode of transportation is a bicycle, you've certainly noticed the hard pinch at the pump. Topping off a boat that carries hundreds of gallons of fuel – gas or diesel – is a particular whammy.
So when Island Pilot began to showcase breakthrough propulsion technology in the form of its DSe Hybrid – a 40–foot catamaran powered both by solar panels and diesel–electric motors – it attracted attention.
ISLAND PILOTPort bow view of Island Pilot DSe Hybrid model. Boaters have long used solar power to juice up batteries, but driving the boat is something else altogether. Indeed, to say the DSe is a radical design is an understatement. Reviewing the boat's specs and drawings and interviewing members of the team that created her, one finds innovation almost everywhere.
It shows in the hull. The boat is a catamaran cruiser – by itself, a relative rarity. But it also has unique full–displacement, wave–piercing hull designs that include a torpedo–like after–body.
It shows in the power plant. The DSe is powered at low speeds solely by the sun. When the batteries are not enough, it uses highly–efficient diesel–electric drives from Glacier Bay to supplement its solar wattage, both for propulsion and house electrical loads.
It even shows on deck. The massive solar panels also serve as an overhanging roof, simultaneously maximizing surface and shading the pilot house, helm and cockpit.
Perhaps most important, this is no demonstration project. The first two boats are already sold. Testing on Hull No. 1 continues in China and the first boat is scheduled to appear in the United States in May. Overall, the company expects to produce nine this year, with the base price for the first models estimated at $500,000.
Ruben Trane, the company's president, said the boat is designed for a live–aboard couple who are looking for moderate–speed, high–efficiency cruising. Though traditionalists may balk at a boat packed with leading–edge technology, Trane is adamant that nothing on the DSe can be considered "bleeding–edge."
"We're not in the business of adopting unproven technology," he said.
HIGH–VOLTAGE POWER
ISLAND PILOTView of Island Pilot DSe from port quarter.
The striking thing about the DSe is that it is essentially a high–voltage, DC–powered vessel. Even when the engines are burning fuel, it is in the service of producing electricity to drive the props.
The diesel–electric system utilizes OSSA Powerlite technology from Glacier Bay, which includes turbocharged, three–cylinder diesels from Mercedes that were originally developed for the Smart Car. They provide 25 kilowatts of DC power from their attached generators.
These may be the smallest electronically controlled, common–rail diesels in the world, but they have a power density that is roughly twice that of any other 25 kilowatt generator available. The engines are installed forward in the hulls, connected by DC power cables to the 35 HP direct–drive electric motors that turn the props. The generators are rated for propulsion duty and can deliver their full power rating for hours. They are also quiet. Glacier Bay specifications state that the 25 kilowatt generator, in its sound shield, generates only 65 decibels at a distance of one meter. That means that under normal circumstances, you will not hear it running.
Everything that happens aboard the DSe runs through the high–voltage DC (HVDC) power buss, which is the heart of the electrical system. Even half of the AC shorepower coming aboard is immediately sent to the battery charger and that buss (the other half powers normal AC loads, such as outlets and the entertainment system).
The solar panels are generating power through the buss and charging the batteries, which are Group 31 Odyssey units from EnerSys. The Glacier Bay diesel generators provide 240 volts of DC power to the buss, and drive the 35 HP electric motors.
