The California Offshore Wind Project: A Vision for Industry Growth report was published by the American Jobs Project in partnership with the Schatz Energy Research Centre at Humboldt State University, Pacific Ocean Energy Trust, and BVG Associates.
"Offshore wind can spur a new wave of innovation in California that will support our climate goals," said Mary Collins, managing director of the non-profit American Jobs Project and lead author of the report.
California needs a "coordinated vision" to create opportunities for workers and businesses and to protect its environmental values, Collins said.
California has a goal of 100% carbon-free electricity by 2045.
Elsewhere, the report recommends California: appoints an offshore wind Tsar to coordinate growth; establishes a market acceleration target; sets a comprehensive approach to guide early development; surveys potential impacts on coast ecosystems; considers innovative financing mechanisms; and cuts red tape.
Additionally, a workforce would have to be developed, ports upgraded, and policies adopted that help align innovation and access to capital with industry needs, it noted.
A 2015 US Department of Energy study called for 17.2GW of installed wind capacity by 2050 off the Pacific coastal states, including Oregon and Washington.
So offshore wind installations totalling 18GW off California by 2045 is "unlikely", said Anthony Logan, wind analyst with Wood Mackenzie Power and Renewables (WMPR), formerly Make Consulting.
Logan added there is a limited availability of sites because of military activity, protected marine areas, fishing and other vessel traffic.
WMPR foresees 1GW of offshore wind off California by 2028, part of 13GW nationally.
Logan noted the Navy and Air Force had suggested excluding wind development from large swathes of the Pacific Ocean, especially off southern California.
He referred to a February 2018 presentation by the military to the US Bureau of Ocean Energy Management (BOEM), which oversees offshore wind development.
"The military [is] coming out swinging on this — it’s pretty discouraging," Logan said.
Collins also acknowledged the Department of Defence, a stakeholder, as a potential barrier.
But she emphasised the department is currently in talks with wind developers and BOEM, that the presidential administration will change, and there is also talk of federal wind leases being issued off California as soon as late 2020.
Two large floating wind projects are currently proposed off the California coast by 2025.
A partnership between Trident Winds and German utility EnBW is developing the 650MW-1GW Morro Bay offshore project, off the central coast.
And a consortium including Principle Power, EDP Renovaveis and the Redwood Coast Energy Authority plans the much smaller 100-150MW Humboldt project off the remote north coast near Eureka.