The Slovenian-based boatyard EJET set out in 2016 to create an electric jet tender that delivered all the benefits of electric propulsion without compromising on the speed and range that large yacht owners desire.
They have now unveiled the results of their research and development – the EJET 4x – a 3.95 metre (13 ft) tender with their optimized RIB hull and an engine providing continuous power of 60 kilowatts. EJET says that is capable of delivering a top speed of 35 knots (≈65 km/h) and a range of 40 Nautical Miles (74 km) at lower speeds.
The development centred around two main aspects of the electric jet tender: fine tuning the hydrodynamics of the V-shaped under-hull to work with the RIB tubes for a stable and smooth navigation at all speeds; and engineering the electric powertrain to bring out the best of the jet propulsion.
Electric boats demand a different approach
CEO of the company Žiga Jarc says “When it comes to electric boating, many people turn to the automotive industry for inspiration, but we quickly realized that this approach comes with limitations. A boat, being on the water, presents a completely different challenge.
“The density of water is 830 times higher than that of air,” he continues “which means it’s like constantly climbing uphill. This led to a host of problems that demanded a different approach and exploring uncharted options.”
The EJET website says that the development process “… included multiple and selected premium and word-renowned partners that we are proud of (Alamarin Jet, Emrax motors, …) and designed a fully customized electric jet propulsion system to fit our needs.”
Žiga says the entire team was committed to creating a solution that is powerful, safe and reliable. “Our aim was to engineer a system that delivers exceptional performance, requiring minimum maintenance, safe and always ready for getting in the water.”
All of these attributes make the EJET an electric option for any leisure boat owner, but there are some aspects particularly suited to the superyacht tender market.
Many owners want to be able to explore the waters where they are moored, but there are increasing restrictions on fossil fuel motors in many eco-sensitive areas. The electric EJET allows them to access these untouched areas, while preserving the natural environment. The other benefit the jet propulsion system brings is the shallow draft that makes beach landings and exploration of hard-to-reach areas much easier.
The craft also features a number of technologies that makes sailing easier, especially for less experienced pilots. The electronic control unit (ECU) allows the novice (or expert) to choose one of three driving modes: Eco, Normal, and Power through a 7-inch touch display with GPS.
Electric jet tender has three modes
The hydraulic steering system was designed in conjunction with the hull properties to provide easy manoeuvring in all weather conditions. There is also an actuator system that operates the reverse bucket system to enable a rapid stop, even at high speeds.
In case of a low battery level, the 4X automatically transitions into its Eco Battery mode, ensuring a secure return to shore or the mother ship. The tender is equipped with LED navigation lighting for better safety during night-time navigation and optional underwater lights are available for night swimming. The tender also has a ski hook for wakeboarding and waterskiing.
The standard battery for the EJET 4X stores 46.2 kiloWatt hours of electricity and can be charged either through a standard 6 kW charger or a fast-charging 12 kW option that completes the process in 4 hours. Charging can come from shore power or from the mothership, with EJET offering dedicated charging stations.
Žiga says “We aim to collaborate with yacht manufacturers who share our vision for a cleaner and more sustainable yachting industry. One possible solution that we highly appreciate is the integration of solar panels into the yacht’s design, enabling the use of clean and renewable energy to power the yacht and charge the tender.”
He says the company is witnessing a significant surge in demand from clients who not only prioritize sustainable yachting but also aim to reinforce their commitment to an eco-friendly lifestyle through their choice of tender.
In addition to the 4X, the company is also working on the EJET 9X, a nine metre (29 ft) tender with a larger motor – 270 kW – and an hydraulic platform that creates a small private beach at the stern.
More information on both boats can be found on the EJET website.