‘Seahorse’ gallops towards prototype stage
torsdag 15. november 2012
Draft: 10 m.
Weight: 13 tons
Vertical struts: aluminum
Cabin: glass-fiber reinforced plastic
Buoyancy Chamber: aluminium and glass-fiber reinforced plastic
Speed: 9 knots
Fuel capacity: 1,000 liters
By Tea Tramontana
After two weeks of tank testing, the Canadian company ExtremeOcean Innovation Inc. has demonstrated that the unique geometry of their offshore service vessel, the TranSPAR Craft, works as intended. Now the Newfoundland based naval architects are seeking $1 million (USD) to build a prototype.
The TranSPAR mimics a seahorse as a result of its extremely small waterplane area and deep keel. Combined, these attributes minimize the movement of the vessel in large ocean swell. With a draft of nearly 10 meters, the TranSPAR ’s deep keel is connected to an underwater buoyancy chamber, which houses a variable ballast system. Sitting atop the keel and buoyancy chamber are two vertical struts roughly eight metres in height. The struts limit the effect of surface waves on the motion of the vessel while supporting the cabin above the waterline.
The result is a significant reduction of vessel motion and of the risks associated with transferring people, supplies, and equipment to and from offshore wind turbines.
ExtremeOcean CEO Peter Gifford, who together with CTO Brian Veitch works exclusively on the design and development of the TranSPAR , explains how the innovative design was derived:
“It was a matter of 10 days of brainstorming when we got the requirements from the Carbon Trust competition. We came up with a range of all sorts of ideas very quickly. Using a structured approach we evaluated 15 to 16 concepts identifying the pros and cons and actually came back to the first and original design.”
The TranSPAR is not the fastest among the concepts selected by Carbon Trust, but as Gifford puts it: “The TranSPAR Craft is perfectly suited to the in-field personnel transfer requirements. Our design focuses on safely and efficiently transferring personnel and equipment with no unnecessary fuel waste.”
He continues: “The TranSPAR ’s advantage over current access solutions is that it provides a reliable and cost effective solution to loading and unloading personnel and equipment to fixed offshore wind turbines in significant sea states.”
Tank tests of a 1:8 scale model proved the capability of TranSPAR to dampen and mitigate wave-induced motions to the vessel. Additionally, tank tests demonstrated TranSPAR ’s stability both at low speed when approaching a turbine and while operating at speed.
“These results were great news. Our concept is, to a large extent, driven by the need to minimize the motion and of course ensure the stability of the vessel. We’ve tested the scale model and are confident that we can meet the requirements of operating in a significant wave height of 3 meters,” says Peter Gifford.
ExtremeOcean Innovation is currently seeking partners with expertise in fabrication, distribution, and service to proceed toward the commercialization of the TranSPAR Craft in the offshore wind turbine service market.
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