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Current Obstacles to Wide Implementation of Wave Energy. Alex Ruane 10/27/05. Overview. Level of Development Progress Output Capabilities Construction and Maintenance Local Impact of Devices Scenic Economic Ecologic Geologic. Stan?. Level Of Development Progress.
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Current Obstacles to Wide Implementation of Wave Energy Alex Ruane 10/27/05
Overview • Level of Development Progress • Output Capabilities • Construction and Maintenance • Local Impact of Devices • Scenic • Economic • Ecologic • Geologic Stan?
Level Of Development Progress • “Ocean energy today probably is about where wind energy was in 1974” – Engineering News-Record Editorial, 7/6/2004 • Most projects are still in development and prototype stages • most prototypes have only been tested in wave tanks at scale • Cannot meet the needs of a large population (see stats) • current output ranges on the order of 1 MW • on average, generate 16 kW per meter of coastline • not yet economically competitive with fossil fuel From Clement et al., 2002, a 120 kW prototype 1.5 km off Nansei Town, Japan
Construction and Maintenance • Hawaiian Department of Business, Economic Development, and Tourism report, 2002: • “By a comfortable margin, the most money and effort being spent worldwide on wave energy development employs the OWC” • Falcao, 2004: • Civil construction dominates costs of OWC plants • Long-term maintenance and lifetimes are unknown • High-energy areas require high construction/materials costs • Difficult (and sometimes dangerous) to construct devices in high-wave areas • Blast cliff away and leave natural dam? • Construct in dry dock and tow to proper location? • The largest plant ever constructed (OSPREY plant in Scotland) was destroyed by the sea shortly after installment (1996) • Integrating OWC plants into breakwater is best option, as construction costs are shared • Already done in Japan and India
Local Impact of Devices • Visual impact can be large for TAPCHAN and OWC devices, less so for the “Mighty Whale” and offshore devices • Strategic placement away from tourist areas a good idea • Noise can also be disruptive for OWC devices • Offshore devices require cables linking bottom anchor to onshore grid as well as anchor-device tether • could disrupt transportation and recreation activities • Offshore buoys would be invisible to most radar • Accelerates coastal erosion on construction, then reduces it during lifetime • Affects coastal property and sedimentation
Local Impact of Devices • Ecological effects could be drastic in small areas • Offshore buoy farms could reduce wave action in sensitive tidal zones] • Lower energy areas could provide shelter to wildlife (like kelp forests?) • Large sections of shoreline would be destroyed for onshore OWC and TAPCHAN facilities • Devices would also be more effective if shallows were dredged deeper • Installation of offshore devices would require extensive cable-laying operations • Danger of providing opening for colonization by invasive species
Final Thoughts • Estimates of high energy resource potential are often misleading • Not all coastlines are suited for development • need high wave energy and suitable coastal features • Energy supplied is variable and inefficient • Much more research and development is required • Variable and small-scale energy source • Better suited to compliment larger projects or to power small/local communities • Pacific Islands, not Nebraska