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Options for Ocean-Based Options for Ocean-Based EnergyEnergy

22ndnd Maritime Business & Technology Maritime Business & Technology SummitSummit

Frank R. Goodman, Jr.San Diego Gas & Electric Company

November 16, 2010San Diego, CA

Ocean Energy Options

• Extraction of energy from ocean• Wave energy

• Tidal energy

• Ocean thermal-gradient energy (OTEC)

• Ocean current energy

• Ocean-based wind and solar energy

Ocean Energy PotentialPhoto courtesy of Pelamis Wave Power

• Wave energy resource estimate for WA, OR, CA is 440 TWh/yr--EPRI and other sources

• Issues for San Diego region• San Diego area is near the

low end of what is available from wave energy, compared to further north on the West Coast

• Wave energy may be better further out

• Ocean current, ocean thermal energy, and tidal resources are modest in the immediate San Diego area

Offshore Low-Cut-In-Speed Wind Turbines

• Wind resources could contribute to energy needs of an offshore platform

• SDG&E has plans to field test a machine on Harbor Island• Goal is to assess the

economic viability in low winds

• Power available varies as the cube of wind speed

• Issues for San Diego region• Would the winds be any

better offshore?• How far out would you have

to go?• Some inland areas have

better winds

Offshore Solar Energy

• Solar resources could contribute to the energy needs of an offshore platform

• SDG&E is field testing 4 experimental solar concentrator systems

• Issues for San Diego region• Sunlight improves as you

move away from ocean

• Marine layer greatly limits amount of sunlight available at coast and at sea

Added Options

• Ocean Algae• Could use nutrients in waste water

• Algae as a transportable fuel

• Use osmosis to confine the growing area

• Osmotic Power

General Issues That Need to be Addressed for All These Technologies

• Cost of energy• Rigorous business case needed

• Environmental impacts need to be addressed• Aesthetic concerns• Ecological impacts• Impact on navigation and shipping

• Can all the energy be used on a large floating platform?• Would there be a need to get energy to the mainland?• How would it be done?

• Extra attention needed to making the equipment corrosion resistant• Example: A wind turbine that is designed only for inland

use will not survive the corrosion at sea

• Recyclability of the materials at end of life• Who will own the systems? Who will operate and

maintain the systems?

Questions?