It seems like science fiction, but it already exists: a Swedish electric boat uses a car battery, carbon fiber hull, and smart hydrofoils to fly over the water and travel 105 km in almost total silence.

Swedish electric boat combines automotive battery, hydrofoils, and electronic control to reduce water friction, extend declared range, and test new possibilities for leisure and silent urban transport.

The Candela C-8, an electric boat developed by Swedish Candela, uses computer-controlled hydrofoils to lift part of the vessel above the water and reduce friction during navigation.

Equipped with a 69 kWh battery supplied by Polestar, the model has a reported range of up to 57 nautical miles, equivalent to approximately 105 kilometers, at 22 knots, according to manufacturer data.

The project’s proposal is linked to a recurring problem of electrification in the nautical sector.

On water, the challenge is not limited to energy storage.

A significant part of consumption occurs because the hull needs to overcome surface resistance during displacement.

In conventional speedboats, increasing speed raises the effort required to push the vessel against the water.

This drag reduces efficiency and can limit the range of electric models.

In the C-8, the solution adopted by Candela was to combine electric propulsion, a lightweight hull, and active hydrofoils.

When the boat reaches sufficient speed, submerged wings begin to generate lift.

The vessel then stops navigating with its entire hull resting on the water and begins to move primarily on these structures.

The visual effect is that of a boat that “flies” over the surface, although the lift continues to be produced within the water.

Hydrofoils reduce energy consumption in electric boats

Hydrofoil technology was already known in the naval sector but gained new applications with sensors, electric motors, and real-time control systems.

In Candela’s case, the company states that its hydrofoil vessels can use up to 80% less energy than conventional boats at high speeds, due to reduced drag.

This data helps explain why electric boats face a different condition than that observed in electric cars.

On roads, part of the losses is linked to tire friction and air resistance.

In rivers, lakes, or at sea, water imposes much greater resistance to the hull’s advancement.

Simply increasing the battery, in this context, does not solve all obstacles.

A larger energy package tends to increase the vessel’s weight, which can amplify the effort required for navigation.

The solution used in the C-8 seeks to reduce energy demand before expanding storage capacity.

In the current technical specifications, Candela reports a cruising speed of 22 knots and a maximum speed of 27 knots.

Previous announcements about the version equipped with Polestar technology mentioned a maximum speed of 30 knots, which indicates a difference between launch information and technical data presented by the manufacturer today.

With the hull raised, the area in direct contact with the water decreases.

The company reports that waves up to 1.1 meters can pass under the vessel during hydrofoil operation.

In this condition, the boat reduces successive impacts against the surface, a common behavior in fast speedboats when navigating over swells.

Electronic control adjusts the Candela C-8 over waves

To maintain stability, the C-8 relies on an electronic control system.

Candela calls this system the Flight Controller, responsible for continuously adjusting the hydrofoils according to navigation conditions.

This system acts on the position of the submerged wings and considers factors such as speed, inclination, waves, and vessel movements.

According to Candela, automatic control reduces the g-forces felt by passengers by up to 90% compared to conventional boats under similar conditions.

The technical difference lies in the integration between hardware and software.

The C-8 is not just a speedboat with an electric motor instead of an internal combustion engine.

The project relies on sensors, electronic processing, movable hydrofoils, and electric propulsion to reduce drag and maintain stable displacement.

The hull is also part of this architecture.

Candela uses carbon fiber in the C-8, a material employed to reduce weight and maintain structural rigidity.

According to the current technical specifications, the boat is 8.5 meters long, 2.5 meters wide, and weighs 1,950 kg.

The capacity currently reported by the manufacturer is five passengers plus one driver.

The motor is the Candela C-Pod, with a power output of 45/50 kW.

These data differ from previous materials, which mentioned space for eight people, and therefore the most recent technical specifications have been adopted as a reference.

Polestar battery brings automotive technology to nautical use

The connection with the automotive industry is one of the central elements of the project.

In 2023, Polestar announced that it would supply the Candela C-8 with the 69 kWh battery pack and DC fast-charging technology used in the Polestar 2 Standard Range Single Motor.

According to Polestar, it was the first time this type of component was used to power an application outside the automotive sector.

The adaptation indicates how systems developed for electric cars can be used in other means of transport, provided they undergo specific integration for each environment.

Batteries, electronic management, fast charging, and thermal control are areas in which the automotive sector has already accumulated industrial scale.

By bringing part of this technology to a vessel, Candela seeks to address a recurring limitation of electric boats: maintaining useful range at higher speeds.

Charging also follows this integration model.

The current technical specifications state AC charging at 11 kW in about 6.5 hours to go from 0% to 100%.

With DC charging, using a 135 kW charger, the C-8 can go from 10% to 80% in less than 30 minutes, according to the manufacturer.

The actual range, however, depends on navigation variables.

Onboard load, wind, water conditions, temperature, and driving mode can alter consumption.

Therefore, the 57 nautical miles reported by Candela should be understood as a declared figure for specific cruising conditions.

Electric hydrofoils arrive in public transport

Although the C-8 is aimed at the leisure market, the same technological basis appears in the Candela P-12, a vessel developed for passenger transport.

The model began operating in Stockholm’s public system, in Sweden, as part of an urban application of electric hydrofoils.

According to Candela, the P-12 operates at a service speed of 25 knots, has exceeded 30 knots in tests, and has a range of up to 40 nautical miles at cruising speed with one charge.

The company also states that the model is the first series-produced electric hydrofoil ferry.

In February 2026, the manufacturer released data from an official evaluation in Sweden regarding the operation in Stockholm.

According to the material, travel time on the route between Ekerö and the center of the Swedish capital decreased from 55 minutes to about 30 minutes.

The same survey, cited by Candela and specialized media, indicated a 94% reduction in carbon dioxide emissions compared to diesel vessels.

There was also a 22.5% increase in the number of passengers on the line during the evaluated period.

These figures refer to the P-12 in public transport operation, not the leisure C-8.

Still, both models share the same engineering logic: using hydrofoils to reduce drag and, consequently, reduce the energy needed to navigate at higher speeds.

Less noise and smaller wake change electric navigation

The technology of electric boats with hydrofoils acts on three observable points in navigation: noise, energy consumption, and the wake left in the water.

The electric motor reduces the noise associated with combustion, while hydrofoils lessen the hull’s contact with the surface.

In urban transport, the wake is a relevant factor because it affects banks, piers, and other vessels.

In the evaluation released by Candela regarding the operation in Stockholm, the wake attributed to the P-12 was 13 centimeters, a level compared by the company to that of a small outboard motorboat.

This characteristic can influence operation in areas with speed restrictions or environmental sensitivity.

Any large-scale adoption, however, depends on factors external to the boat, such as charging infrastructure, acquisition cost, local navigation rules, and specialized maintenance.

In the leisure market, the C-8 occupies a specific segment of high-tech electric vessels.

The proposal combines a declared range of 57 nautical miles, an automotive-derived battery, and elevated navigation on hydrofoils.

The price and availability, however, keep the model distant from immediate popular application.

A technical reading of the project shows that nautical electrification does not depend solely on engine replacement.

In fast boats, efficiency also involves hull design, weight reduction, electronic control, and the way the vessel interacts with the water.

The Candela C-8 brings these elements together in a leisure product, while the P-12 applies the same logic to public transport.

In both cases, the available data comes primarily from the manufacturer and from evaluations released about the Swedish operation, which requires separating declared information from results already observed in service.

By using an electric car-derived battery and reducing hull contact with the water, the C-8 demonstrates a technical alternative to extend the range of electric vessels.