A boundary-pushing superyacht design leans heavily on sustainability with fossil-fuel-free propulsion.
Concept yachts usually dwell in the land of make believe, where designers dream up futuristic fantasy craft with bells and whistles that are not yet capable of being developed (or making Elon Musk blush). Then there’s Futura, a 216-foot, fossil-fuel-free
innovation from the Dutch design firm Vripack.
The superyacht offers its share of “out there” features—a see-through glass superstructure, a full DJ booth, a whirlpool—but its hybrid-electric drive system focuses on sustainability through existing, proven technologies. Like most concept designs, Futurawill likely never be built, but two interesting pieces of its onboard equipment will almost surely play a role in future applications: an electricity-generating kite system and a bio-battery, which uses all-natural materials including sand, salt and water to store
The kite system incorporates a 295-square-foot sail that launches from a mounted crane at the push of a button and extends to 656 feet, at which point it flies in a figure-eight pattern as it slowly pulls out more wire. The other end of that wire is attached to an electric motor. As the wire plays out, the motor turns, generating electricity that’s fed into the battery.
“It’s like a very big version of the bicycle light you had as a kid,” says Marnix Hoekstra, Vripack’s co-creative director. “As the wheel turned, the generator turned, and that powered the light.”
When the kite reaches the end of the wire, at 1,312 feet, the electric motor quickly reels it back in to 656 feet and the process starts again. The system works whether the boat is at anchor or on the move, although wind speed and apparent wind does matter. The more force there is pulling on the kite, the more tension there is placed on the wire, and that generates more electricity. According to Hoekstra, the amount of energy created is the same as running a generator that produces 110 to 120 kWh.
All of that power feeds directly into the battery, which uses a recently developed super-material known as graphene (a two-dimensional, honeycomb-structured layer of graphite that has highly conductive properties) housed in a solution of saltwater and sand. Such batteries, made of completely biodegradable materials, can recharge and discharge at the same time. They also endure indefinite recharge cycles and offer capacity similar to that found in lithium ion. “It’s our magic box,” says Hoekstra. “From an operational and science point of view it’s a clean solution, it’s safe, and it doesn’t produce any heat or gas. It’s designed to provide one megawatt of electricity.”
Like anything else, however, there are limitations. Unlike a car or phone battery, the bio battery can’t produce fast, high-volume discharges or recharge quickly. Instead, it produces steady energy over long periods and recharges the same way. “It’s not a complete breakthrough; the innovation is the volume involved and that it’s a low-energy battery,” says Hoekstra.
And while the battery’s shape is flexible—it can be designed to fit in a variety of spaces—it does require a large area, which adds weight and takes up room. “The space requirement is probably about the same amount of room a fuel tank would take up,” says Hoekstra.
But unlike the kite system, which is scalable, via a smaller kite with a shorter wire, such batteries will always need the sort of volume that only makes sense on larger yachts that don’t require high-output bursts of energy, i.e. speed. And while these technologies offer more promise for the future, Vripack has working prototypes of each.