Current Obstacles to Wide Implementation of Wave Energy Alex
Ruane 10/27/05
Slide 2
Overview Level of Development Progress Output Capabilities
Construction and Maintenance Local Impact of Devices Scenic
Economic Ecologic Geologic Stan?
Slide 3
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
Slide 4
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
Slide 5
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
Slide 6
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
Slide 7
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