Green Solutions

Green Solutions
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Huisfit is offering a wide range of green solutions to reduce the use of energy.

Are you sailing a superyacht with 20th century technology? And keen to embrace all the latest hybrid technology benefits? A conversion by Huisfit from conventional into hybrid is the ultimate systems upgrade with leading-edge propulsion and power generation.

Hybrid delivers exceptional lifestyle and environmental benefits including silent operation, zero emissions, peak-shaving, shaft-generated power under sail and reduced fuel consumption, together with enhanced operational flexibility and redundancy. As an example of its practical application, this hybrid system offers the potential of navigation in ‘zero emission’ zones.

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Royal Huisman is the shipyard that pioneered hybrid propulsion with the game-changing ketch Ethereal (the world’s first hybrid superyacht delivered in 2009) and has continued to refine its technological lead with the ‘NextGEN’ ketch Elfje and some remarkable projects including the hybrid conversion (by Huisfit) of the 1999 cutter Foftein and the 1993 ketch Juliet. 

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Huisfit is leading the way by retrofitting older yachts like Foftein, first delivered in 1999, and Juliet, first delivered in 1993. Juliet had a hybrid engine fitted to reduce her emissions.”, February 2022

The 44m / 143ft Royal Huisman cruising ketch was launched in 1993 and is a fine example of pioneering, custom-built technologies in late 20th century yacht building. With nearly a quarter million of ocean miles under her keel, she still looks and sails like a dream. Technologies have, of course, evolved rapidly. Hybrid propulsion and power generation systems are delivering exceptional lifestyle and environmental benefits.

As an example of its practical application, this hybrid system offers the potential of navigation in ‘zero emission’ zones. Recognising that they, too, can enjoy these enhancements to their cruising lifestyle, the owners have booked a hybrid conversion for Juliet at Huisfit.

Juliet Hybrid Propulsion Line by Huisfit 02rc v2

The centerpiece of Juliet’s hybrid conversion is a new gearbox, aligned with a sophisticated new electric motor/generator. This facilitates direct electric propulsion, either generated by the main engine or drawn from the new, high performance battery bank or generator.

Conventional shaft drive directly from the engine remains an option, as well. The system enables the main engine to meet the yacht’s ‘hotel load’ requirements by means of the electric motor/generator, whilst the power management set-up also provides additional silent options via the advanced battery bank.

Huisfit2020 Juliet m Norway1c by capt Jonathan Allan resize

With the main engine becoming the primary source of power generation, the system is configured to deliver peak shaving from the battery bank – for example during sail hoisting and maneuvering.

The thrusters are electrically rather than hydraulically-propelled. The same battery bank will enable ‘silent ship’ operation, including air-conditioning and hotel load consumers.

Under sail, electrical power will be generated by the propeller’s rotation – answering every sailor’s dream to hoist the sails, capture the wind and silence ‘that noisy and smelly engine’. Rapid re-charging of the battery bank is provided by the electric motor/generator driven by the main engine or generator. At anchor, battery power replaces the gensets as the main power supply, eliminating the noise and atmospheric pollution that can detract from the harmony of pristine anchorages.

Captain of Juliet, Jonathan Allan: "The hybrid system has been a great upgrade, decreasing fuel consumption while increasing redundancy for propulsion, maneuvering, and electrical distribution. We were amazed on the initial sea trials when it became clear that the hybrid system was fully operational and only required parameter adjustments."

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All of the above will ensure a much-reduced requirement for the main generators in their traditional role. They will offer a high level of redundancy, both for the propulsion via the diesel-electric system, and as an alternative source of electrical power generation. In the latter role, the main engine’s generator would typically be the first choice for the recharging of the batteries after hours of zero emission mode.

Read more about the onboard experiences of the new hybrid propulsion and energy system on this website: news > captain's review of hybrid [link]

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Potential peak shaving principle after hybrid conversion by Huisfit:

The yacht’s power requirement is mainly handled by 1 generator which is sized to the average load. Short peaks handled by battery pack, low battery power forces second generator to kick in for short periods of time. See graph on full page and read more: link (opens new tab).


Juliet Fiji by capt Jonathan Allan 0011editbyOwen cres

Huisfit is offering a number of smart hybrid upgrade solutions to have all the latest technology benefits and reduce the use of energy: the ultimate systems upgrade with leading-edge propulsion and power generation.

Could Huisfit be the smart choice for your project, too? Please contact the team to discuss and see more of the ultimate hybrid upgrade solutions by Huisfit.