Article by Frances and Michael Howorth
DESIGNERS OF ELECTRIC TENDERS ARE PUSHING THE BOUNDARIES OF TENCHNOLOGY AND AESTHETICS IN THEIR QUEST TO DELIVER ECO-FRIENDLY TENDERS TO SUPERYACHTS WORDS: MICHAEL HOWORTH
Demand is growing for the marine industry to provide clean, quiet, and affordable alternatives to combustion engines for use in Tenders. Experts in the field of clean energy are confident that the new breed of electric motors coming onto the market will satisfy both boat builders and end user requirements. As a result, there is an air of excitement among boatbuilders who believe clean and quiet alternatives are about to change the way tenders are built and used on board superyachts.
Electric engines are designed to be a direct replacement for a traditional diesel engine both in size and cost. Already several 48 volt DC electric motors, designed to replace small diesel engines are available for boats up to 10 metres and larger canal craft. Companies are manufacturing and marketing marinized chargers and inverter/chargers which, when working alongside lead acid and lithium batteries, complement and facilitate the use of electric motors to drive water jets and conventional propellers.
The efficiency of these new style drives means that there are new tenders emerging onto the market that offer an excellent range as well as being easy to service and maintain on board the mothership. Without the need of water cooling systems or gearboxes and with their direct connection to shafts, electric tenders are, right now, at the cutting edge of technology. Several are now beginning to emerge onto the market that feature motor direction, throttle and navigation controls in one digital colour touch screen display that really look like the future has already arrived.
For those looking to reduce both noise and emissions, the affordable electric option offers really efficient and reliable electric that are sensible alternatives to the traditionally powered superyacht tender.
Rim-driven and brushless motors capable of delivering more torque using less energy are becoming available to boat builders and with new lithium batteries capable of storing a higher charge from deep cycle charging which crucially can be repeatedly undertaken without damage, the electric boat scene is gathering momentum. One of the most recent breakthroughs in the world of electric motors, comes from Siemens who have designed a motor for the aeronautical industry that could well be adapted they say, for marine use. With a weight of just 50kg the motor delivers a continuous 260kW (348hp), at just 2,500rpm which is about five times more power than equivalent systems.
With a new generation of digital controllers, managing the ebb and flow of energy with predictive intelligence and the fast development of battery technology, things are looking up. The Dutch manufacturer Mastervolt pioneered full-size 12 and 24 volt lithium-ion batteries for marine use. Their second generation, Ultra range are one third of the weight of an equivalent lead-acid design and come with a claimed life cycle of at least 2,000 deep discharges. Complex electronic circuitry connecting each cell ensures perfect charge and discharge balancing, and guards against the risk of overcharging.
Batteries employing the use of oxygen as one of the reagents are in development and could, be made for a fifth of the price and a fifth as light as lithium, and offer operation times five times longer. Graphenano based in Spain has developed a graphene polymer battery called the Grabat, which it claims is 33 per cent the weight of lithium ion and four times the energy density. These batteries can recharge 33 times faster than lithium ion, and retain over 80 per cent of their capacity.
When it comes to powering yachts by electricity it would seem that the future is not far away. But what we do know is, that some of the electric tenders on offer are also pushing the boundaries of design aswell.
A motorboat built with passion and a love of detail. I you have grown up with boats and have very high expectations for a motorboat of sophisticated technical design and at the same time competitive performance. Back in 2013, Nina and Christian Lex devoted themselves to the challenge: their own boat brand. A boat with style, elegance and individuality – modern with a sense of tradition, the unique eLex 610 and now the sporty and longer Lex 790 have arrived. In a short space of time the brand Lex Boats became a large part of the electric boat scene.
For over 25 years Budsin has been building some of the finest electric boats available. The boats are crafted one at a time by people who love their job. They range in size from 15 to 22 feet and their virtually silent operation provides hours of running time, with top speeds of five to seven knots. Conversations can be conducted at normal levels and the driver’s controls are convenient and unobtrusive, demanding very little attention. Handling is accurate and smooth, it will do a 180° in a boat length. Hand made by passionate and skilled craftsmen, so if you’re looking for something a little more subtle and special, give Budsin a call.
The innovative team behind Q-Yachts conceived the vision of bringing to the market a unique boat which offers the same experience of relaxed speed and silence, that sailing offers. Thanks to the innovative propulsion technology and the hydrodynamically optimised hull, the boat produces minimal noise and wake. The Q-Yachts concept represents yet another ncessary step in the evolution of boating – where the journey truly becomes the destination.
SAY CARBON YACHTS
The SAY 29E currently holds the record as the fastest e-boat in the world (series production, 8-10 m). The 48kn fast and extremely seaworthy carbon composite construction is powered by a drive from Kreisel Electric, the most innovative supplier of e-mobility in Europe. A staggering 360 kilowatts provide the thrust for breathtaking acceleration and make the 29E the forerunner of a new generation of tenders and chaseboats. Her wave cutter bow and the sidewings of the ultra-light hull (at only 400kg) provide maximum stability and enable incredibly high speeds on all water conditions. Behind this special boat, the SAY brand and at the head of the shipyard is Karl Wagner, one of the most experienced carbon specialists in Europe. With his expertise Wagner raised the in-house quality standard and engineering at SAY to an automotive level and optimised the production.
The new Tender 15 is a superyacht tender with timeless modern style. In typical German fashion, it is uncompromising in terms of handling, ergonomics and functionality . SCHAAF have designed the ideal vessel for shuttling guests to and from the mothership and exploring idyllic bays. Probably the most striking feature are the purpose. These allow the tender to be easily and safely placed on any garage platform without the need for expensive adjustments. This tender is very well positioned with a choice of jet propulsion or outboard. But with their sustainable approach, the Tender 15 is also available with an electric motor.
Vita Yachts was established in 2017, with the aim of bringing the latest in automotive technology and engineering to the marine world. Its team comprises a naval architect at the forefront of electric boat design, a head of production from the superyacht industry, and a head of power and performance who was formerly a key member of the Mercedes F1 Engines team. Vita has been a major sponsor of the Blue Marine Foundation since 2018, with a percentage of each sale committed to the conservation of the world’s oceans.
The innovative Danish boat manufacturer RAND Boats offers 4 unique tender models ranging from 5.4m to 8.5m. Among the four models, the luxurious and sporty Supreme 27 is the perfect companion for superyachts, and can easily be lifted onto the deck due to its low weight, or be used as a chase and sports boat with its strong offshoring capabilities. The overwhelming space aboard the Supreme 27 culminates at the aft size three-man bed. Whatever the purpose you are sure to arrive in style with one of the most trailblazing and sustainable boats on the market.
Beau Lake’s Tahoe ’14 Electric Runabout combines the beauty and mystique of classic wooden boat aesthetics for today’s ecoconscious audience. Co Founders, Lee Kline and Paul Lavoie, look back to the craftsmanship of bygone eras with tremendous respect and look to emulate that kind of quality in everything they craft. The self-draining electric boat consists of three
primary construction components; the hull, cockpit liner and deck surface, while an ergonomically designed, hand-carved wooden tiller with joystick component steers its course. The Runabout’s molded fibreglass body, inlaid maintenance-free veneer deck, compartmentalized cooler that contours to the boat and beautifully finished stainless steel castings and hardware invoke the essence of a Beau Lake state of mind. Added luxuries includes marine upholstered seating, Bluetooth speaker system and accent lightening. The luxury Electric Runabout is propelled by Torqeedo’s German engineered 2.0 PodDrive.
This Swedish first class manufacturer of 100 percent electrical crafts, is leading the way in the marine industry with the market’s most modern e-boats. X Shore crafts are built and designed around three main pillars: design, technology and sustainability. The combination of speed and distance in an electric boat is what makes X Shore’s crafts unique. Today the boats reach top speeds of 40 knts and a fully charged battery can take you a distance of 100 nautical miles. The hydrodynamics collaborates with Rolls Royce to test and develop the most advanced hull, shaft, propeller and rudder.