Sweden's Candela -- being dubbed the "Tesla of the seas" -- is one of the companies at the forefront of the electric watercraft revolution, which is about a decade behind the electric car revolution, led by Tesla.

In 2019, Candela launched its first luxury model, the C-7, which it touted as the "first electric boat with enough range and speed to compete with fossil fuel powerboats on equal terms -- but also offers benefits not seen before in maritime history."   

Last week, venture capital-backed Candela signed a substantial partnership agreement with Polestar Automotive Holding (PSNY -0.34%), a Swedish electric vehicle (EV) maker whose stock began trading in June. This partnership is another reason why investors might want to consider buying shares of Polestar, the former performance car unit of Sweden's Volvo Cars, which is owned by China's Geely Automobile Holdings.

A Candela C-8 boat, with two passengers, operating in a body of water.

A Candela C-8 electric boat. Image source: Candela.

The Candela-Polestar partnership 

Under a multiyear partnership, Polestar will supply lithium-ion batteries and charging systems to Candela. This teaming "marks one of the world's first direct battery technology collaborations between companies from the automotive and marine industries," according to Polestar's press release.

Candela founder and CEO Gustav Hasselskog called Polestar a "dream partner." He said the combining of Candela's hydrofoil technology -- we'll get to this cool tech in a moment -- with high-capacity batteries from Polestar will enable the companies to "speed up the mass-market adoption of electric boats."

Candela's hydrofoil technology 

Candela's electric hydrofoil technology is the secret sauce that enables its premium boats to travel a significantly greater range on a charge than similar electric boats made by competitors. This tech also provides other advantages for passengers, such as a smoother ride.

Computer-guided hydrofoils lift the hull (or body) of Candela's boats above the surface of the water -- as shown in the above image -- which results in up to 80% less energy use at high speeds compared with traditional motorboats. This reduction in energy consumption translates to a much greater range per charge than electric boats with similar batteries.

Candela's vessels might have the appearance of flying, but they're not actually doing so. The winglike structure of the hydrofoils -- which are retractable -- are submerged in the water when the boats are in foiling mode.

Candela's boat models

Candela, which manufactures its boats in Sweden, delivered 32 C-7 models from 2019 to 2021. This small model was custom-built and meant as a kind of proof of concept.

The larger and even more efficient C-8 is the company's next-generation boat, designed to be mass-produced. This luxury craft has space for eight passengers and beds for two adults and two children.

With more than 150 units sold, the C-8 is currently Europe's best-selling electric premium boat, according to Candela. Moreover, it's also reportedly one of the top-selling premium 28-foot powerboats in Europe, regardless of power source. Deliveries are set to begin any time now.

Cutting-edge tech and luxury don't come cheap. The C-8 starts at 280,000 euros -- and thanks to the strong U.S. dollar, the starting price is now also about $280,000 for American buyers. For most folks, this is an ultra-high price, but it's in the same ballpark as other similarly sized luxury boats, according to Candela.

Moreover, the C-8's total cost of ownership should be considerably less than a comparable fossil fuel luxury boat. Electric boats need less maintenance and their "fuel" -- electricity -- is less expensive.

The C-8 is powered by a 44-kilowatt-hour (kWh) lithium-ion battery. It has a range of more than 50 nautical miles (about 57 miles) at a cruising speed of 24 knots (about 27 miles per hour), and has a top speed of 30 knots (about 35 miles per hour). So, operated continuously at a fast cruising speed, the C-8 will last just over two hours on one charge. Many boaters will slow down or idle during their excursions for various reasons, so a typical outing could last notably longer before recharging is needed.

For some context, Tesla's standard version of its Model 3 sedan has a battery capacity of about 60 kWh and a range of 272 miles.

Later this year, Candela plans to expand into the commercial market via the launch of its P-8 Voyager taxi boat and P-12 electric ferry.