If a name of a yacht could fit an occasion then that name would surely be the 58m / 190.4’ sailing yacht Ethereal; on a beautiful day in October, Bill & Shannon Joys’ mighty Ethereal literally hatched from a three year incubation emerging from her construction hall as the largest singular piece of yachting excellence to come out of Royal Huisman since the mighty 79m / 260’ (90m / 295’ including spars) Athena had done four years earlier.
Suggesting an almost ‘Ethereal’ presence, a cloud of early evening fog masked Ethereal’s handsome hull form in a shroud of mystery as she transited overnight her water highway en route to salt water and mast stepping in the nearby Dutch seaport of Harlingen. Less than a week later she lies at her berth, masts stepped and awaiting her first engine and sail trials. And what trials these promise to be. At this stage one can only imagine how an extract from the Captains first log entries might read.
Lets hope it’s something like this:
0800 - Slipped the mooring lines in Harlingen. Cleared port control and motored out of the harbor to find adequate maneuvering room. At 177 horsepower each I couldn’t believe how quiet the electric Van der Velden thrusters are. Thanks to the hub less units it was very noticeable that I had equal and plenty of power thrusting either to port or starboard maneuvering off the dock and in the basin. We did a few full rotations using thrusters only. The rotation time was an impressive 1 minute and 40 seconds in either direction. The stern thruster is a nice treat. Combined with the twin Wärstilä variable pitch propellers and the mechanical hand steering (I didn’t use the hydraulic joystick tiller) maneuvering is very rewarding. The helm station feels good. The controls are well positioned and the visibility around the deckhouse is excellent. Well done Ron and Pieter.
0920 – The Shipyard Engineers called to switch to ‘Silent Running’. Yikes I thought. So soon – but then again this is what we are here for. We switched over from Conventional to Hybrid drive. The total Insulation package, also with sound shields around the main engines and generators is so quiet I couldn’t hear the engine shutdown whilst the 400 kWh of Lithium Ion batteries took over. It’s hard to believe we can actually do this, let alone with a yacht of this size. We went through the complete power curve from idle to full speed. Other than the sound of the wind we were silent - in full ‘stealth’ mode. The guys also told me that the equivalent conventional supply of electrical power would be around 3 times heavier and 2 times the volume as the lithium package! At 400 kWh – that’s a theoretical 40 kW of power for 10 hours for considerably less weight and volume!
1000 – ‘Silent running’ at 10 knots we loaded the batteries further with the household loads that until now had been designated to one of two 90 kW generators. For additional safety we do have a third emergency set, at the owners request, with full functionality. Air conditioning, Propulsion, Refrigeration and general lighting and instrumentation are now running on battery power alone. We then shut down the generator to appreciate the full effect. Strange feeling to be on a 58m yacht in full operation under battery power alone!
1120 – Anchor trial and a quick lunch. Dropped both hooks in 20m. Deployed the articulated stern platform and the concealed side gangway. The boys did a few ‘more’ alarm and fire hose tests whilst at anchor. A few guys went up and down to ‘trial’ the hydraulic crows nest elevator mounted on the mizzen and main mast. No lack of volunteers here - I think it was more of joy ride to appreciate the view some 30m off the deck! The high position and push button access to it, will sure make visual navigation in unchartered waters a lot more comforting. We fired up the SLCE water maker; an interesting piece of equipment. It re-uses the still pressurized discharge water to pre pressurize the incoming water before it goes to the high pressure feed pump of the membranes. Energy saving – about 4 kW.
1300 – The breeze has filled in to around 12 knots true. Great time to take a first sail. The Shipyard Engineers want to do the whole maneuver using only the batteries that were coincidentally trickle charged whilst we lunched. So it was anchor up, some engine and some thruster work to hold Ethereal head to wind, whilst we raised the main, mizzen and unrolled the headsail using the wireless remote sail controls. The household load was running below deck. We tacked around for about an hour rolling and unrolling sails before some ominous looking thunderclouds helped us to decide that it was time to go home. Although the batteries still showed a healthy charge the engineers wanted to try another variation of the Ethereal Hybrid drive on the way back.
1420 – Sails are all down and we are motoring back to harbor. The whole idea is to keep trying systems on these trials. For a change we are this time using the generators in their ‘go home’ mode. This is a compromise and considered as an ‘emergency only’ go home system. Still it’s possible and if you are happy for slower speeds it is an option. No batteries, no main engine, just the generators running the shaft driven generator in it’s opposite function as an electric motor. And as I just found out, we are able to trickle charge the Lithium Ion batteries at the same time. It’s interesting to note that because of the special insulation package and special glass to the living areas we need only 90 kW generators to meet the reduced demand on the entire Household load including the Airco system. My last job on a boat of this size we had 140 kW sets. This big reduction in requirement is helped by new developments with low voltage, low heat LCD lighting and the simple fact that the entire living area of the interior is fully insulated. Floors, walls and ceilings are insulated to a level that the entire living space could be efficiently chilled and made into a multi compartment, walk in freezer! Of course the opposite effect could be achieved with heating – a giant pizza oven for high latitude cruising!
En route we try another variation of the Hybrid system. This time we shut down the generators and run just one of the two main engines and cruise at about 10 knots. The residual power of the Main now also runs the inline shaft driven Generator to supply AC voltage directly to the household consumers. If this combination were to become overloaded then the stored energy in the Lithium Batteries can provide AC current and absorb the temporary peak loads to save a ‘standard’ generator from having to kick in. If on the other hand you throttle back or the household consumers demand less power the batteries then provide an artificial load bank to store the surplus energy and maintain a constant load on the main engine. Naturally this helps to prevent the age old problem of carbon build up in diesel engines when they are under-loaded. And of course in this scenario I would end up with a spare main engine. When motor sailing I will also have the luxury of using the leeward engine which is generally a very efficient way of making distance using less fuel.
1600 – We are just outside the Harbor. Port control wants us to wait for a cargo ship to leave before going in. We decide to test the ‘station keeping’ mode. This is a black box controller that interfaces with the GPS for position and B&G for wind information. Collectively they hold Ethereal on station. It controls the bow and stern thrusters as well as both main engines and of course the rudder. In the cross tide in front of the harbor it does a pretty good job although the yard engineers think it will need a little extra calibrating. Still it worked and that’s why we are on trials. This system too can be done using the Hybrid or conventional system. Great I thought for holding station over a pod of whales in ‘stealth mode’.
1625 - We are called on the VHF to enter the Harbor. Whilst waiting we drop anchor. The yard engineers want to take a few preliminary noise and vibration measurements. With no carpet and headliners installed (the yard keep these dockside during trials for cleanliness and accessibility to equipment) I’m amazed that I couldn’t hear or feel any change when we shut down and went back to batteries. We are now in full stealth mode at anchor. Batteries only. It reminded me of being on 30 footer 30 years ago, at anchor, batteries and the old system of ‘hold over cold plates’ in the freezer fully charged for the night. My mind wonders off to the Caribbean this Christmas; the owners and guests swimming around the boat, no exhaust gas or sound from Generator sets. Cocktails in the cockpit, dinner in the dining room with only the noise of laughter and shooting stars to break the nights quiet! This is really going to be a new dimension for Super yachting I thought.
1720 – Time to enter harbour - anchor up - with the wind now gusting to 25 – 30 knots it was comforting for me to know how the thrusters and twin propellers had performed earlier. Using the Joystick tiller we are now docked not a scratch, after an impressive and unusually quiet first day on trials. It’s also amazing to think that Ethereal has been built with a refit in mind. The boss, knowing future technologies has already pre-planned a retrofit to a fuel cell power system.. A retrofit so well conceived it would not require major modifications! I have a lot yet to discover about this boat in the months ahead. Can’t wait for tomorrow.