Get our free book (in Spanish or English) on rainwater now - To Catch the Rain.

Humboldt Wave Energy

From Appropedia
Jump to: navigation, search

Wave energy has the potential to be a major contributor to the supply of economic, renewable energy in California. Currently Pacific Gas and Electric co. is exploring the feasibility of harnessing wave energy off the coast of California. The PG&E website states that, “Studying the potential of ocean wave energy is important to California's environmental future and the ongoing discovery of sustainable, renewable energy sources.” This page is dedicated to the PG&E's work off the coast of Humboldt County in Northern California. To read more about wave power see the wikipedia article on wave power.


Introduction

Pacific Gas and Electric Co. (PG&E) began studying the feasibility of wave power off the coast of Northern California in 2007. This study led to a proposal in 2009 to research and develop possible wave energy systems off the coast of Northern California. The proposal was called the Humboldt WaveConnect™ pilot project.

The proposed Humboldt WaveConnect™ pilot project was suspended in Fall 2010.[1] The main reasons for canceling the project were that the costs rose above the level of expenditure that the company could justify and a lack of available technology.[2]

Humboldt WaveConnect™ Pilot Project

The WaveConnect™ Program was introduced by PG&E in 2009.[3] Part of the program proposed a pilot study to be conducted off the coast of Humboldt County in Northern California.

The area of study was off to be located just outside of the Humboldt Bay. The preliminary permit allowed PG&E to conduct studies only, not construction, exclusion, or any physical disturbance.[4]


Technology

Several different types of technology were to be used in the pilot project. Wave energy is a new frontier for renewable energy and consequently PG&E wanted to try several different approaches to harness the energy. A maximum of four wave energy converter technologies were to be selected for the study location, each with an array of one or more devices.[5] [6] [7]

Attenuator

Attenuators are long, multi-segmented structures that float parallel to the direction of the wave. As a wave passes, it causes the structure to bend at the segments; this bending motion is converted to electricity.

Point Absorber

Point absorbers are floating structures that have that are moved by wave action. One component is moved by the wave while the other is stationary. This relative motion drives devices that convert movement into electricity.

Oscillating Water Column

Oscillating Water Column devices extend perpendicular to the direction of wave travel and capture or reflect the power of the wave. Water enters through a subsurface opening into a chamber with air trapped above it. The wave action causes the captured water column to move up and down forcing the air though an opening connected to a turbine.

Oscillating Wave Surge Converter

OWSC's operate somewhat differently than other technologies. Unlike most, which move vertically with the waves, OWSC's oscillate horizontally (parallel to the motion of the wave). These structures are typically used closer to shore (10-20m). [8]


Challenges

  • New technology
  • Developing regulatory framework
  • Uncertainty of environmental effects [9]
  • Conflict with existing uses
  • High Costs[10]
    • PG&E estimated the cost of installing the infrastructure for power transmission, monitoring, and other equipment to be $50 million.
    • Operation and maintenance cost of the project was estimated at $5 million annually. This cost excludes the expense of carrying out environmental protection measures.

Suspended

The cost of securing government permits, installing the prototypes and putting in place the infrastructure needed to bring the power to shore made the project untenable.[11]

Future Projects

PG&E is currently studying the feasibility of the Central Coast WaveConnect project off the coast of Santa Barbara County. PG&E filed for a FERC permit in December 2009 for this site, which could have a capacity up to 100 MW. The permit was granted in May 2010.

References

  1. http://cwec.ucdavis.edu/forum2011/proc_open/Forum2011_Caliendo.pdf
  2. http://www.renewableenergyworld.com/rea/news/article/2010/11/pg-e-no-longer-pursuing-humboldt-waveconnect-ocean-energy-project
  3. "Humboldt WaveConnect Pilot Project." Pacific Gas & Electric, Web. 09 Oct. 2012. <http://www.pge.com/about/environment/pge/cleanenergy/waveconnect/projects.shtml>..
  4. http://www.pge.com/includes/docs/pdfs/shared/environment/pge/waveconnect/FERCPreliminaryPermitAreaMap.pdf
  5. http://www.pge.com/about/environment/pge/cleanenergy/waveconnect/projects.shtml
  6. http://ocsenergy.anl.gov/guide/wave/index.cfm
  7. http://www.sciencedirect.com/science/article/pii/S1364032109002652
  8. http://rsta.royalsocietypublishing.org/content/370/1959/345.abstract
  9. http://magazine.humboldt.edu/spring09/wave-energy-deemed-feasible-but-gnarly/
  10. http://www.renewableenergyworld.com/rea/news/article/2010/11/pg-e-no-longer-pursuing-humboldt-waveconnect-ocean-energy-project
  11. http://www.sfgate.com/business/article/PG-E-suspends-wave-energy-project-off-coast-3247529.php