Wave EnergyWave Energy

Kate RileyKate Riley

Energy AlternativesEnergy Alternatives

Spring 2007Spring 2007

Physical Properties of WavesPhysical Properties of Waves

Waves are created by wind passing over Waves are created by wind passing over large bodies of water.large bodies of water.

Waves are measured by their:Waves are measured by their: Height (H)Height (H) Wavelength(Wavelength(λλ)) Frequency (v)Frequency (v) Period (T)Period (T)

Development of Wave EnergyDevelopment of Wave Energy

North Atlantic has highest potentialNorth Atlantic has highest potential

Most development along European coastMost development along European coast

Estimated 30GW-80GW in UK aloneEstimated 30GW-80GW in UK alone

Worldwide estimates 2 TW or Worldwide estimates 2 TW or 17,500TWh/yr17,500TWh/yr

Development of Wave TechnologyDevelopment of Wave Technology

Leaders in researching and investing in Leaders in researching and investing in wave technology:wave technology: UKUK NorwayNorway JapanJapan Rep. of IrelandRep. of Ireland AustraliaAustralia IndonesiaIndonesia

What does it take?What does it take?

High average wave High average wave energyenergy

Persistent wavesPersistent waves Deep water close to Deep water close to

shore (decreases shore (decreases frictional energy loss)frictional energy loss)

Small tidal range Small tidal range (<1m)(<1m)

Conducive natural Conducive natural coastlinecoastline

Does Belize have what it takes?Does Belize have what it takes?

There is currently no wave technology There is currently no wave technology operating or being researched in Central operating or being researched in Central AmericaAmerica

Belize is a poor candidate in spite of Belize is a poor candidate in spite of having an extensive coastlinehaving an extensive coastline

Coastline is sheltered by reef and islandsCoastline is sheltered by reef and islands Shallow water is not ideal Shallow water is not ideal

Devices are classified by two Devices are classified by two criteria:criteria:

Location: Location: fixed to seabedfixed to seabedfloating offshorefloating offshoretetheredtethered

……and Orientation:and Orientation:terminatorsterminatorsattenuatorsattenuatorspoint absorberspoint absorbers

Oscillating Water Column (OWC)Oscillating Water Column (OWC)

1.1. An artificial gully is An artificial gully is constructedconstructed

2.2. Water acts as a Water acts as a column, rising and column, rising and falling with the falling with the waveswaves

3.3. This draws water in This draws water in and out of the top and out of the top chamber and acts as chamber and acts as a piston to drive the a piston to drive the turbineturbine

Tapered Channel (TAPCHAN)Tapered Channel (TAPCHAN)

1.1. Waves are funneled Waves are funneled into a tapered into a tapered channelchannel

2.2. Their height Their height increases until they increases until they spill into an elevated spill into an elevated reservoirreservoir

3.3. Water turns turbine Water turns turbine as it is returned as it is returned down the gradient down the gradient into the oceaninto the ocean

Wells TurbineWells Turbine

Self-rectifying: can Self-rectifying: can accept airflow in accept airflow in either directioneither direction

Similar to horizontal-Similar to horizontal-axis wind turbinesaxis wind turbines

Eliminates need for Eliminates need for gearbox because of gearbox because of increased speed increased speed potential (increases potential (increases energy captured)energy captured)

The Ups…The Ups…

Very small environmental impactVery small environmental impact• No chemical or noise pollutionNo chemical or noise pollution• Low visibilityLow visibility• Do not interfere with migrating fishDo not interfere with migrating fish• Can create a haven for marine lifeCan create a haven for marine life

Small impact on shipping and marine Small impact on shipping and marine industriesindustries

Floating devices will not impact coastal Floating devices will not impact coastal environmentenvironment

……and the Downsand the Downs

May alter coastline and concrete structures must May alter coastline and concrete structures must be removed at end of operationbe removed at end of operation

Insignificant amounts of greenhouse gases Insignificant amounts of greenhouse gases releasedreleased

Intermittent resourceIntermittent resource Expensive to install and maintainExpensive to install and maintain Damage is frequent due to violent stormsDamage is frequent due to violent storms Cables from offshore devices to transmit energy Cables from offshore devices to transmit energy

are neededare needed

Is it worth the trouble?Is it worth the trouble?

So far most wave So far most wave technology is technology is theoretical or in the theoretical or in the experimental stageexperimental stage

Main costs= Main costs= installation and installation and maintenancemaintenance

Devices with high Devices with high durability and few durability and few moving parts are bestmoving parts are best

¿Preguntas?¿Preguntas?

SourcesSources Boylr, Godfrey. Boylr, Godfrey. Renewable Energy, Power for a Sustainable FutureRenewable Energy, Power for a Sustainable Future. .

London, UK. Oxford University Press. 2004London, UK. Oxford University Press. 2004 http://www.seapower.se/http://www.seapower.se/ http://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/wavehttp://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/wave

%20power.htm%20power.htm http://www.oceansatlas.org/unatlas/uses/EnergyResources/http://www.oceansatlas.org/unatlas/uses/EnergyResources/

Background/Wave/TAPCHAN.jpgBackground/Wave/TAPCHAN.jpg http://earthtrends.wri.org/pdf_library/country_profiles/http://earthtrends.wri.org/pdf_library/country_profiles/

ene_cou_084.pdfene_cou_084.pdf

Other Images:Other Images: http://americandigest.org/mt-archives/wavejapan2.jpghttp://americandigest.org/mt-archives/wavejapan2.jpg http://dode777.jeeran.com/rogue-wave,1.jpghttp://dode777.jeeran.com/rogue-wave,1.jpg http://www.tulane.edu/~sanelson/images/oceanwave.gifhttp://www.tulane.edu/~sanelson/images/oceanwave.gif