1. Ocean Wave Energy
Lilian Busse

2. What we agree on:
That we need more renewable energy
What we don’t agree on:
That Ocean Energy is a good renewable energy source, and it’s worth spending money in research and development

3. Outline Comparison to other renewable energies
Basics of ocean wave energy
Technological status
Possible locations for ocean wave energy
Funding issues for ocean wave energy
Benefits of ocean wave energy
Needs in R&D for ocean wave energy devices

4. Renewable Energy Sources
Ocean energy wave energy is behind wind and solar energy developments
85% fossil based
8% nuclear
4% hydro
Less than 4% is Solar, Wind, Geothermal 8%
(6% geothermal, 2% solar and wind)
44%
48%
(Source: POEMS)

5. Potential for Ocean Wave Energy
Potential world wide: 2,000 TWh/year (10% of the world electricity consumption)
(Clement et al. 2002)

6. Comparisons to other renewable energy sources
Northern CA: 30 kilowatt per m wave crest (with storms 1 Megawatt per m)
Solar energy: 300 watts per m2
Wind energy: 800 watts per m2

7. Types of Ocean Energy From tides From waves Thermal energy
Mechanical energy
From tides
From waves

8. 3 basic systems for ocean wave energy devices
1. Channel systems that funnel waves into reservoirs
2. Float systems that drive hydraulic pumps
3. Oscillating water column systems that use waves to compress air within a container
mechanical power either directly activates a generator, or transfers to a working fluid, water or air, which then drives a turbine/generator

9. Technological status of wave energy
Ocean energy today is where wind energy was in 1974
Many devices have been invented, only some tested and evaluated, only a few tested at sea (most in wave tanks)
Since 1855: 1000 patents
Some are already tested in the field (e.g. Island of Islay in Scotland, LIMPET (Land-Installed Marine Powered Energy Transformer) – 500 kW – sufficient for 400 homes)

10. Locations of ocean wave energy devices
The western coastline has the highest wave potential in the US (Northern CA)
Floating or completely submerged
Offshore or onshore, on the seabed
Most of prototypes have been places at or near shore
Wave power at deep sea ocean sites have 3-8 times more the wave power than coastal sites (but more expensive)

11. Global Coastal Wave Power Estimates
Europe: Denmark, Norway, Sweden, Ireland, UK, Portugal
(POEMS)

12. Funding for Ocean Wave Energy
limited research due to the lack of federal funding
European Union funds Ocean wave energy since 1992 with a total Euro 9.5 for 9 years
Investment by both public and private sectors is essential
investment costs of 820 billion Euro
(Clement et al. 2002)

13. Benefits of Ocean Wave Energy
Why better than other renewable energies
Available 24/7 on 365 days - therefore power produced from them is much steadier and more predictable – waves can be accurately predicted 48 hours in advance and therefore forecast energy output (BUT irregularity in wave ampitude, and direction)
Good data on waves from wave monitoring bouys
Wave energy contains 1000 times the kinetic energy of wind (can produce the same amount of power in less space)

14. Benefits of Ocean Wave Energy – cont.
General benefits of Ocean wave energy
Reduce dependence on a specific source
Energy security for US
New business development in local geographic region
Can provide many coastal locations with energy
In remote areas (islands) wave energy is an attractive energy because of high energy import costs
$ 0.12/kW min. cost for wave energy conversion -Baltimore: $ 0.06/kW -San Diego $ 0.13/kW -Australian Island: $ 0.45/kW

15. Benefits of Ocean Wave Energy – cont.
Impact on the environment
“pollution-free”
Less infrastructure (no access roads), and less space
Quieter and less visual obtrusive than wind devices

16. Needs in research and development of ocean wave energy devices
Cost reduction
Efficiency and reliability improvements
Identification of sites
Better understanding of the impacts of marine life and shoreline
Weather effects over the life of the facility and the ability to survive in the marine environment (e.g. hurricanes)
Therefore more research and development money is needed to make ocean wave energy competitive!

17. Sources POEMS: Practical Ocean Energy Management Systems, Inc.
ENR: Engineering News-Record
Previsic, M. 2003: The state of the Art in Wave Energy Conversion. Sea Technology 44 (7),
Feasibility of developing wave power as a renewable energy source for Hawaii. Department of Business, Economic Development and Tourism, Jan
Clement et al 2002: Wave energy in Europe: current status and perspectives. Renewable and Sustainable Energy Reviews 6,