The MODX is a 70ft catamaran with fully automated twin inflatable rotating wingsails set on telescopic retractable masts and powered by electric motors with variable pitch, hydrogenerating propellers.Every now and again something really different comes along, and this was one of those concepts you don\u2019t think will come to reality. I say that, having spoken to the design team about it years ago, and seen plenty of renderings of what it might look like.
\nSo, the curiosity of such a venture we expected. The fact that our video tour from its launch at the International Multihull Show in May was one of our fastest to reach 100,000 views, less so. Also noteworthy with that video is the sheer amount of largely positive comments supporting the technological development (when you consider that these comments stem from a typically sceptical audience).
\nEverything about this project is quite fascinating, from the VPLP-designed wave-piercing hulls to the automated power and sail systems. A primary goal for the MODX is to offer zero CO2 emission cruising by utilising completely renewable energies.
\nThe scheme carries plenty of credibility, thanks to design by VPLP and construction by Oc\u00e9an D\u00e9veloppement, the yard responsible for the fleet of MOD 70 ocean racing one-design trimarans built in 2008.
\nThermoplastic polyurethane wingsails are raised on rotating, telescopic masts. Photo: Ronan Gladu
\nHowever, it\u2019s those enormous wingsails which spike the most interest, of course.
\nBuilt by Aeroforce, a company set up specifically to develop the technology, these twin AF125s are each 125m2 inflatable wings with auto trim functionality. They\u2019re claimed to be 1.7 times more efficient, safer (no winches\/ropes), and create 20% more space aboard than conventional rigs.
\nBlow up sails
\n\u201cPowerful and stable wings that can be automated is why we developed Aeroforce,\u201d CEO Jean Guyon told me during the yacht\u2019s premiere in La Grande Motte. \u201cThe MODX\u2019s goal was to be energy independent. So we needed a fast boat, but it\u2019s also why there are wingsails \u2013 the target was that in 10 knots wind, we should do 10 knots boat speed.\u201d
\nThe telescopic masts are formed of six sections which rotate around bearings at waterline and deck level. The masts are 23m high when fully raised and have a deep reef to reduce the sailplan to 65%. (It\u2019s worth noting that most sailing footage so far shows the yacht in reefed format.)
\nSails are inflated to their aerofoil shape \u2013 a process that takes just eight minutes. Photo: Ronan Gladu
\nThe wings are housed in huge cradles above the coachroof and take eight minutes to hoist and inflate. Made from thermoplastic polyurethane (TPU), these sails are inflated to a comparatively low pressure of 100 millibar, or around 10 times less pressure than a typical inflatable paddleboard \u2013 which allows pumps to be used for inflation rather than compressors.
\nThe wings also have a trailing flap, which works like those of an aeroplane to increase lift by 30-40%, Guyon estimates. He explained how the airfoil shape increases airflow on both sides of the wing, \u201cso pointing is quite good at 40-45\u00b0 to the apparent wind.\u201d
\nIn terms of performance, the MODX has hit 21.5 knots in 25 knots of wind at 150\u00b0 to the apparent, or 9.5 knots in 11.5 knots at 46\u00b0 apparent \u2013 which is already very close to the initial target of 10 knots in 10 knots of wind.
\nThe gearbox and rotating chain used at the mast bases allow for 360\u00b0 rotation of the wings, providing a tangible benefit for spilling wind. Consider how smooth and quiet gybes can be when you can completely open the sails and rotate the masts downwind through the gybe. This brings us to the yacht\u2019s impressive automatic operation.
\nThe 70-footer also offers luxurious accommodation. Photo: Martin Viezzer
\nAuto functionality
\nThe MODX is piloted from a single wheel and internal helm station, adorned with touchscreens. \u201cThe project is trying to attract people from power without the complexity of sail,\u201d is how VPLP\u2019s Mathius Maurios explained the concept to me.
\n\u201cIt\u2019s about being on the water without being stressed.\u201d With this in mind, the project team wanted a fully automated sail\/wing control system, as easy to use as cruise control.
\nThe aft owners cabin is luxurious. Photo: Martin Viezzer
\nThey worked with Madintec to develop a highly sophisticated yet approachable wing, hydro and energy management system.
\nThis French company has developed performance autopilot systems for many of the top IMOCA 60 teams. So when you look at the helm station on the yacht, on one side is the throttle control for the electric engine, and on the other, a more crude, simple throttle lever (which looks like something out of a Thunderbirds rocket).
\nA solo-operated 70ft cat? Helm station has throttles for the electric motors and wind engine. Photo: Chloe Lambelet
\nSo, in terms of piloting this 70ft performance catamaran, once wings are raised, the operator simply pushes the wing throttle lever forward, selecting from 0-100% of potential force. Therefore, it\u2019s not just an auto-driving boat, but one that uses auto-tuned sails too. If you only want 50% of the power available, it\u2019ll release the sails to spill more wind.
\nSilent sailing, silent power
\nWith no running rigging, the coachroof can be pushed out to maximum beam, creating the largest area possible for solar panels. The MODX has 70m2 of panels, which provide a peak of 15kW, or up to 35% of its electrical energy mix. Although the company is looking into a flybridge alternative to cater to demand, this wide, flat surface on the first boat is also ideal for harvesting rainwater, and there are two 400lt tanks dedicated to this.
\nNo side decks, engines or tender aft \u2013 instead clear transoms and a huge aft leisure cockpit. Photo: Ronan Gladu
\nAt the heart of the electrical system is a 250kWh LFP lithium battery bank \u2013 as a comparison a battery in a large electric car is around 90kWh. It\u2019s enough for guests to live aboard for 10 days without sun, wind or engine use, or provides 110 miles motoring range at 5 knots. When sailing, the variable pitch propeller can hydrogenerate power back into the battery bank. So, at 15 knots boat speed, it\u2019s possible to generate 16kWh back into the system.
\nUnfortunately, what we can\u2019t show you is the nucleus of the MODX system: its technical rooms. I was granted a quick look but not allowed to take photos or video. These are located at the mast bases at the foot of each forward companionway and house the electrical and telescopic mast systems, in a cocoon of carbon fibre with significant bulkheads to help support the latter. Otherwise, the MODX is built in glassfibre, using bio-sourced resin and 40% recycled foam.
\nA throttle lever is used to control sail power. \u201cA \u2018wing throttle\u2019 is the best way to think about the power of the wing, like an engine throttle,\u201d says Aeroforce\u2019s CEO Jean Guyon. Photo: Yachting World
\nThe rest of the interior in the first boat is suitably luxurious, particularly on the main deck, which offers motoryacht-style comfort, near-surround ocean views, and 135m2 living space in the saloon, fore and aft decks. However, we can\u2019t go into more accommodation detail as it\u2019s a largely customisable space to suit private, charter or \u2018expedition\u2019 use.
\nA MOD Future?
\nSo what is the future for this concept, and what size vessels might the Aeroforce wings be practical for? \u201cThe initial design was for 55ft, but we needed more solar to reach the efficiency targets,\u201d Guyon explained. The right balance of solar and boat speed was found at 70ft. He added that doing a 100-footer would be easier than a 55: \u201cI don\u2019t see the potential in less than a 100m2 wingsail size.\u201d
\nAeroforce is also looking at the obvious potential of its wings for commercial shipping, as well as for leisure monohulls, where they might provide less heeling moment and more thrust.
\nMODX specifications
\nLOA: 21.33m \/ 70ft 0in
\nBeam: 10.00m \/ 32ft 10in
\nDraught: 2.00m \/ 6ft 7in
\nAir draught: 4.60m \/ 15ft 1in
\nWing area: 2 x 125m2 \/ 2 x 1,345ft2
\nDisplacement: 30,000kg \/ 66,138lb
\nElectric motors: 2 x 20kW \/ 2 x 27hp<\/p>\n
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The post MODX: An electric 70ft catamaran with inflatable wingsails! appeared first on Yachting World.<\/p>\n","protected":false},"excerpt":{"rendered":"
The MODX is a 70ft catamaran with fully automated twin inflatable rotating wingsails set on telescopic retractable masts and powered by electric motors with variable pitch, hydrogenerating propellers.Every now and again something really different comes along, and this was one … <\/p>\n