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July 2013 www.sname.org/sname/mt Southeast National Marine Renewable Center (SNMREC) at Florida Atlantic University. Something old, something new For naval architects and marine engineers, MRE oers a lit- tle of everything traditional plus several unique challenges, all wrapped in a new package. Consider, for example, the challenge of capturing the energy of ocean currents and tidal ows using underwater turbines. Rotation rates much slower than those of propellers mean that rotor designs will likely lean more toward those of wind turbines. However, the forces of the water?generally an order of magnitude larger than those in air would be for similar amounts of power?mean that structural designs must be signicantly strengthened not only for rotor blades and hubs but also for bearings and gear assemblies. Underwater operation, as always, adds complexities and challenges that dwarf those in the world of wind power. Deep-water deployments, in particular, will require moored, buoyant systems that must operate autonomously below the draft of surface ships and remain stable in the face of currents that vary in three-dimensional space as well as in time. Yet the design of such systems?which will likely require hydro- dynamic control surfaces to augment controllable buoyancy in order to achieve system stability?must include provisions for maintenance procedures in ways that are both safe and economical. In addition, the anchors and mooring hardware itself must accommodate both these dynamic consider- ations and, in some fashion, electrical transmission. ese examples for open-ocean currents are mirrored for tidal ows and wave energy. In all cases, the mechanical systems must be integrated seamlessly with the control and power-generation electronics, with autonomy in operation a guiding principle. While many of the challenges involved have analogies in more traditional naval architecture and marine engineering elds, the requirements for MRE equip- ment also include new and unique challenges that, in turn, require new educational preparation. A ?rst step At this stage of the industry, it is premature to invent new college-level majors or other specialized sequences. Still, it is appropriate to begin thinking about the edu- cational pipeline problem to prepare students who may wish to pursue such training in the future. To that end, SNMREC has developed a secondary-school curriculum that can be presented in pieces or as a package to mid- level high-school students. It was designed specically to be compliant with state of Florida educational standards for science (the Sunshine State Standards?), yet it was also designed to be self-contained in order to minimize the need for prerequisites. To that end, it covers a broad range of topics including background associated with renewable energy generally and topics beyond the tech- nology of MRE. e six main lessons in the curriculum, each designed to be covered in 2-4 class sessions, reect this philosophy and are structured as follows. LESSON 1. Why do we need renewable energy? A survey of how society depends on electricity and the vari- ous concerns about dependence on fossil fuels. LESSON 2. How is electricity generated? Some of the basic physics of electricity and magnetism, including Ohms Law and an exercise in which students construct simple electrical generators from soda cans. LESSON 3. How do we identify energy from ocean currents with the best potential for producing energy? Very basic oceanography with emphasis on the Gulf Stream. LESSON 4. Harnessing energy from ocean cur- rents: e new renewable. Overview of the technology involved with MRE recovery, including turbines and some fundamental physics such as the Bernoulli eect. LESSON 5. What are the environmental impacts of ocean energy? Introduction to issues concerning eects of MRE recovery on sea life, with an emphasis on Florida species and a comparison of renewable and non-renew- able energy sources and the environment. LESSON 6. e future of ocean energy. Overview of the various modes of ocean energy (waves, tides, currents, and so forth) and their potential with an emphasis on the fundamental physics of ocean ther- mal energy conversion. In addition to these lessons, the curriculum includes background material for teachers with an extensive bibliography, as well as a list of supplies needed and, Underwater operation, as always, adds complexities and challenges that dwarf those in the world of wind power.