[ 28 ] THE SHIP OF THE FUTURE The largest double-enders designed and built up till the Fusion-class were BC Ferries’ 21,777-gross-ton Coastal-class. The 160m and 28.2m beam Coastal-class double-enders have a capacity of 34 trucks on the main deck and 185 cars on a separate upper deck. By way of comparison; the 230.5m long and 30.8m beam Fusion-class pair each has a capacity of 158 trucks and 182 cars on a dedicated car deck. We gained first-hand experience from a few international double-ender operations, focusing on the speed element. Yet, the size of the double-enders operating on Scandlines’ Puttgarden-Rødby and ForSea’s HelsingørHelsingborg route respectively, came nowhere near to the Fusion-class. NO STONE LEFT UNTURNED Although the double-ender solution may sound a simple one, the decision wasn’t taken lightly. We weighed all the pros and cons of both a single-ender and double-ender design. This was a fairly long process but, ultimately, the double-ender design proved to be the most sustainable solution. The fuel savings generated by eliminating up to ten 180° turning manoeuvres per day over at least 20 consecutive years would outweigh the extra cost to build a double-ended ferry. The hybrid diesel-electric propulsion system with four ABB Azipods isn’t inexpensive, but it’s yet another solution that pays off in the longer term as maintenance costs on single-enders like the Spirit-class are high; the Spirits each have four main engines, four auxiliary engines, four shaft generators, two gear boxes, three bow thrusters, two steering gears and two rudders. This is immensely complex with high maintenance costs. Compared to the Spirits, we are, thus far, assuming that the Fusionclass’ maintenance spend will be 50 per cent lower while the refit costs on a five-year survey cycle will be 30 per cent lower. We calculated that for three double runs with 40-minute port turnarounds, the average service speed could be reduced from 19.1 knots for a single-ender to 15.6 knots for a double-ender design. Such a significant speed and fuel reduction was only possible by avoiding turning manoeuvres in port. We also had long debates about the size of the vessel and whether we should have a third, separate car deck on Deck 7 similar to the Spirit-class. Separating cars and vans from big trucks through a dedicated car deck accessed via fixed ramps speeds up vehicle deck operations, but it also adds weight and volume to the ship, increasing the ship’s size and gross tonnage. This, in turn, affects the port expenses as harbour dues are typically based on a ship’s gross tonnage. Instead of a separate car deck, hoistable car decks on the upper freight deck were considered with all the pros and cons weighed once again. We evaluated six main scenarios with ships varying in length between 214m and 244m, bearing in mind that 232m was the maximum length for a single-ender, dictated by the turning circle in the Port of Dover. The passenger capacity was equally evaluated as was the crew-to-passenger ratio. Both the Darwin-class and Spirit-class each have a capacity of 2,000 passengers. P&O Ferries’ Spirit-class reach a full occupancy rate of 2,000 passengers for only 0.2 per cent of their sailings. Transporting less than 600 passengers for 80 per cent of the sailings, the ships carry a lot of “air”. Up to EUR 1.5 million of CAPEX savings could be achieved by lowering the passenger capacity from 2,000 to 1,500. The layout of the two passenger decks allows for sections of the accommodation to be closed off. As certain facilities such as the Food Market and Quiet Lounge are duplicated, the onboard services and offerings remain guaranteed at all times. REDUCING PORT TURNAROUNDS Every single parameter influencing the design was scrutinised, including port infrastructure. Bearing in mind that the Fusion-class is goaled on keeping fuel consumption and the emissions footprint 40 per cent below that of the Spirit-class, port infrastructure is critical in the ship’s energy consumption picture. The main message here is minimising port turnarounds to maximise the ship’s time at sea, either by making extra roundtrips or further reducing speed. The double-level linkspans in both Dover and Calais allow for simultaneous two-lane loading/unloading. Increasing the number of lanes to three, would reduce the time at berth by six minutes. The time gain from automated mooring and automated linkspan systems in both ports would be even more significant — up to 25 minutes per roundtrip. “ Every single parameter influencing the design was scrutinised, including port infrastructure. Bearing in mind that the Fusion-class is all about keeping fuel consumption and the emissions footprint 50 per cent below that of the Spirit-class, port infrastructure is critical in the ship’s energy consumption picture. The main message here is minimising port turnarounds to maximise the ship’s time at sea, either by making extra roundtrips or further reducing speed”
RkJQdWJsaXNoZXIy NzQ1NTk=