Skip to main content

Hanse’s E-Motion Electric Rudder Drive

           Hanse’s E-motion electric rudder drive represents a true breakthrough in auxiliary propulsion for saiboats   

           Hanse’s E-motion electric rudder drive represents a true breakthrough in auxiliary propulsion for saiboats   

When news that Hanse Yachts had launched a new form of electric-powered yacht first broke in the winter of 2016, it was widely reported. After all, Hanse is one of the world’s biggest builders of sailing boats, so this had the feeling of a breakthrough to it.

After nearly a year, though, just a handful of the “E-Motion” rudder-drive-equipped Hanse 315s have been sold, and by its own admission, Hanse is disappointed. “The problem is that people are still quite skeptical about electric propulsion on water, and we are perhaps a bit ahead of time with this,” says Hanse’s Florian Nierich.

It’s not a problem with the boat itself: the 315 is a feisty little sailer that has already sold 140 units, including more than 15 in North America. The issue is price, a basic diesel-equipped 315 costs $120,300. Stick an electric motor on, along with the necessary lithium-ion batteries, chargers, controllers and more, and you add $13,270. If you want a kind of “turbo-charged” system with more batteries and a charger that will allow you to top off in as little as three hours, that will set you back $26,554.

“The boat is way too cheap for the electric motor,” admits Nierich, “If a customer had the extra money, they’d buy the Hanse 388 instead.”

Which is not to say that the E-Motion rudder drive isn’t still a really neat idea. The system is basically a Torqeedo 4.0FP pod drive (providing roughly the power of a 10hp diesel) connected to a 5.4kWh lithium-ion battery bank and encased in the rudder itself—a true first for a cruising boat. The batteries are fitted under the berth in the aft cabin, and the engine compartment under the companionway is given over to a 4.4kW Whisper Power generator, which serves to extend the boat’s range, if necessary. The controls in the cockpit consist of a kill switch, an electronic display that toggles through various different motor performance data, and a small, low-profile throttle within easy reach of the helm.

According to Florian, Hanse had to slightly redesign the rudder of the 315 to accommodate the pod, but otherwise, the boat is the same as those equipped with a standard diesel engine. Neirich notes that Hanse worked with its rudder supplier, Jefa, on the engineering, adding, “The one stringer in the rudder was at the perfect place for the pod.”

Hanse also engineered a cover that screws on over the cavity around the pod, preserving the hydrodynamic shape of the rudder and allowing the pod to be easily accessed for maintenance and cleaning. Otherwise, the propeller is the standard Flexofold used on all the other Hanse 315s.

           The electric motor and prop are integrated into the rudder’s trailing edge   

           The electric motor and prop are integrated into the rudder’s trailing edge   

Put to the Test

Conditions were ideal on test day: plenty of sun and a good 20-knot breeze kicking up a chop on the cabbage-green waters of Holland’s IJsselmeer. We began by simply motoring down the short access canal to the marina. In these smooth waters, the boat was soon moving at 6 knots, making a noise like an egg-beater at its full throttle position. Acceleration is strong, but smooth, thanks to Torqeedo’s electronics.

Boatspeed naturally dropped in choppier waters, to around 5.1 knots at full power with the wind just off the bow. Motorsailing in the same conditions, the pod boosted our speed by about 1 knot, from 6.5 knots to 7.5 knots. Just as it would using a diesel, the extra power from the motor also allowed us to point closer to the wind without sacrificing speed.

Next, we tried reversing into the wind (with the sails furled, of course). Surprisingly, the motor on our test boat, at least, was set up to develop less than half its rated power when running astern. Nonetheless, its 1.9kW took around 15 seconds to bring us to a standstill from full ahead and was then enough to get us butting backward into the wind and the chop at 2-3 knots.

One problem I did note: putting the pod in the rudder makes the propeller the aft-most point on the boat, and liable to cavitation as the boat pitches astern. The prop’s position also poses a danger to swimmers and even those just reaching over the transom. “We are aware of this,” says Nierich, adding that the decision to position the prop where it is, resulted from that fact that it’s “a better point on the rudder in order to put less strain on the rudder bearing.”

As with a diesel engine, range drops off dramatically at higher revs—from about 15 miles at 4.5 knots of boatspeed to just 9 miles at 6 knots. The range-extending generator from Whisper Power along with a 26 gal fuel tank can give you hundreds of extra miles.

           The low-profile controls won’t catch on lines   

           The low-profile controls won’t catch on lines   

Close Quarters

Of course, what really sets an electric boat apart from its diesel cousins is its maneuverability and the fact that it supplies full torque across most of its speeds, supplying thrust more quickly than a diesel. This is doubly true of the Hanse 315, because the tiller turns the prop through a full 100 degrees of arc, creating that much more leverage with which to spin the boat.

I’d seen the videos, but it is something else altogether to feel the way she actually swings round: literally turning on the spot, so that suddenly, the prospect of maneuvering into a really tight marina berth becomes a good deal less intimidating. In fact, the reflexes of this boat mean you can wait until the last minute before putting the helm over, and that you can expect to get round much tighter corners.

My only gripe is that having lower power astern deprives you of that useful ability to really jam on the brakes. That said, there is no prop walk, and the forces on the tiller when motoring astern are low because the rudder is always exactly parallel to the wash from the propeller. As a result, the maneuverability at every point of the turn is simply outstanding.

Up in the cockpit, the small electronic throttle is flush mounted, so it can’t tangle with lines, and it has the same angular, modern design as is found on Torqeedo’s outboards. There’s a bit of feel as you nudge forward or back. However, I found the neutral lock button poorly positioned and stiff, making it harder to flick instantly from ahead to astern when maneuvering. A lock is, of course, necessary, but it wasn’t quite where I naturally gripped the lever.

Verdict

The electric revolution is coming to sailing. It may take a generation, but in time we’ll all be relying on electric propulsion, and Hanse has now positioned itself at the forefront of this movement. Torqeedo’s pod system is impressive. It gives the boat phenomenal maneuverability and eliminates the noisy, smelly chug of the diesel. On the downside, it is still relatively expensive, so you need to find a reason to spend that money. Kudos to Hanse for its pioneering efforts in the area. 

Photos and images courtesy of Hanse

May 2018

Related

Rescue

Cruising: Safety Lessons Learned

It’s not often that sailors get a chance to put their rescue and MOB training to the test, rarer still that they do as quickly as newbie California sailor Khosrow “Koz” Khosravani did recently. If and when an emergency situation ever arises, though, it pays to be prepared. This ...read more

01-LEAD-'22.01.10_FALKEN-Maiden_Emma-Bow

At the Helm: Sailplans

The first thing you notice when you look at the sailplan for the Farr 65, Falken, which Mia and I recently added to the fleet here at 59-North, is the sheer number of headsails. Falken was built in 1999 as a racing boat to go around the world, and the crew would have carried the ...read more

01-PR-2-Throwing-it-Back-_©LaurensMorel

Racing Class Reunion

Where does an old VO70 go to retire? Right back to the racing circuit, apparently. This spring saw a remarkable contingent of Volvo Ocean Race one designs back on the water and duking it out on the Caribbean circuit. While it’s no surprise that some of the VO65 teams intending ...read more

05-Sailboats-moored-in-sheltered-waters-off-of-Kärrsön

Charter: Sweden

With 2,000 miles of coastline, 270,000 islands and seemingly countless bays and inlets, Sweden is truly a sailor’s paradise. One of the top sailing destinations here is the archipelago just outside the country’s second largest city Gothenburg (locally known as Göteborg), on the ...read more

fa70b13c-8eec-4c35-b30f-f89e497b469a

Crowdsourcing Age-of-Sail Weather Data

Although big, multi-million-dollar projects like the Large Hadron Collider and the human genome project with their legions of PHD’s tend to grab headlines, there’s still a part of play for the “citizen scientists” of the world. Amateur birders have long contributed to an ...read more

01-LEAD-Ultime-race-Yvan-Zedda,-OC-Sport-Pen-Duick

Ultims to Race Solo Around the World

For years now, maxi-trimarans, both solo-sailed and fully crewed, have been racing the clock on their own around the world in an effort to set ever faster records for the world’s fastest circumnavigation under sail. Back in 2000-01 there was also a no-holds-barred ...read more

P1-01-LEAD-018_CARYNBDAVIS_AMISTAD

Juneteenth on the Water

Discovering Amistad and Mystic Seaport Museum have partnered to organize their third annual Juneteenth festival, featuring concerts, speakers and a reflection on the lasting legacy of racial injustice in America. Declared a National Holiday in 2021, Juneteenth celebrates the end ...read more

Lead-2021-01-17-vue-03-34-av-tb-01

New Multihulls for 2022

Lagoon 51 In keeping with many of the more recently launched models created by French multihull builder Lagoon, the Lagoon 51 is all about comfort, “en plein air,” in particular, as the French might say. Topside, a whopping 80 percent of the boat’s flybridge is given over to ...read more