Abstract
The PG&E WaveConnect project was intended to demonstrate the technical and economic viability of wave power in the open ocean adjacent to PG&E’s service territory. WaveConnect was conceived as a multi-stage development process leading to long-term megawatt-scale wave power production. The first-stage tasks consisted of site selection, permitting, pilot plant design, and assessment of technology and commercial readiness. The second stage would have included development of infrastructure, undersea cabling, and deployment of wave energy conversion devices (WECs). In the third stage, the most promising WEC devices would have been deployed in larger quantities and connected to the grid. The program was halted near the end of the first stage for reasons described below. This report documents the findings of Stage One, which was funded by the California Public Utilities Commission (CPUC) for $4.8 million and by the U.S. Department of Energy (DOE) for $1.2 million, for a total of $6 million.
Site Selection
After studying the wave energy potential, grid interconnection and other project infrastructure along the California coast, PG&E selected two sites: one near Eureka, called the Humboldt WaveConnect (HWC) project, and another near Vandenberg Air Force Base, called the Central Coast WaveConnect (CCWC) project.
Permitting
FERC issued PG&E preliminary permits for HWC in 2008 and for CCWC in 2010. PG&E chose to use FERC’s recently promulgated Pilot Project Licensing Process (PPLP), which was intended to streamline licensing to allow relatively quick and easy installation, operation, and environmental testing for pilot projects. Permitting, however, proved to be complicated, time consuming and expensive, mainly because of the uncertain impacts of WEC devices. As WaveConnect efforts proceeded, PG&E learned that even under the PPLP the project would still require a full analysis under the California Environmental Quality Act (CEQA), including an Environmental Impact Report, as well as Monitoring and Adaptive Management Plans (MAMPs) and other requirements that had significant cost and scheduling implications. A majority of Stage One efforts were expended on permitting activities.
Pilot Plant Design
PG&E prepared a conceptual design for a 5-MW pilot test facility at the Humboldt site, which consisted of an off-shore deployment area where WECs of different designs and from different device manufacturers could be tested. PG&E was to provide permitting, subsea cables, and onshore facilities necessary to connect WaveConnect to an existing PG&E substation, while the WEC manufacturers would provide, operate and maintain their devices during the test period.
Technology and Commercial Readiness
PG&E issued a Request for Information to the wave power industry to assess the technical and commercial capabilities of WEC manufacturers. Sixteen manufacturers responded, representing the four best-known and most mature WEC designs: the attenuator, point absorber, floating oscillating water column (OWC), and oscillating wave surge converter (OWSC). PG&E found that WECs are early-stage devices with evolving designs and little real-world operating experience. These characteristics made environmental impacts difficult to assess, which complicated permitting efforts. It also made a megawatt-scale demonstration project difficult to support because early stage WECs are costly and have limited track records for performance and reliability.
Results
PG&E withdrew its Draft Pilot License Application (DPLA) for HWC in November 2010 and surrendered its preliminary permit for CCWC in May 2011, effectively discontinuing the WaveConnect project for the following combination of reasons:
- Permitting issues were much more challenging than originally anticipated. Stage One project funding of $6 million proved insufficient to complete the necessary development and permitting work. During Stage One development, PG&E determined that permitting costs would be $2 million to $5 million greater than originally budgeted.
- The cost of developing a five-year, 5-MW WaveConnect pilot project at Humboldt Bay is much greater than the $15 million to $20 million originally estimated. Even assuming that vendors provide WEC devices at no cost to the utility, which was the proposed strategy with WaveConnect, PG&E concluded that a pilot project comparable to HWC would cost approximately $47 million. If WEC devices were purchased for such a project, its total cost would be on the order of $90 million.
- It is unclear when or if wave power will become competitive with renewable energy alternatives. Significant additional investment in design, testing and demonstration will be needed to improve designs and reduce costs. Using a vendor-provided installed cost goal of $2500/kW for mature WECs in five to 10 years, PG&E concluded that their LCOE would be in the range of $175–$250/MWh, which is not competitive with current or near-term renewable alternatives such as wind or solar photovoltaics.
Although PG&E discontinued the WaveConnect project and no WEC devices were deployed, WaveConnect advanced PG&E’s understanding of the technological, engineering, permitting, environmental, economic, stakeholder, and related issues involved in undertaking any wave power project now or in the future. As WEC technologies mature, and regulatory and permitting agencies grow more familiar with their environmental impacts, PG&E believes that wave power will merit further evaluation, demonstration and deployment.