The US state of California’s nation-leading ambitions to build out as much as
50GW of floating wind plant off its coast by 2045 could be facing an unexpected hurdle, following the decision by the Department of Energy (DoE) to extend the submission window for a key energy support programme that could result in the state’s lone nuclear power plant – currently viewed as an important landing point for future deepwater wind power in Pacific – to be kept operating.
At California’s request, the DoE recently revised its criteria and extended the application period for its so-called Civil Nuclear Credit (CNC) programme, with the
Diablo Canyon nuclear power plant (DCPP), slated for closure by its local utility-owner PG&E in 2025, now in the frame to continue running and so raising a question mark over the grid interconnection capacity at present earmarked for first floating wind projects in lease areas off the state's central coast.
Ana Matosantos, cabinet secretary for the office of the California governor Gavin Newsom, wrote to energy secretary Jennifer Granholm requesting the amendments to the CNC programme, stating: “To maximise options to maintain electricity reliability as new projects come online, the state is evaluating a temporary delay of the planned retirement of DCPP.”
California is
struggling to balance its grid amid a profound energy transition targeting 60% renewable energy by 2030 and 100% clean power by 2045, prompting state leaders, including Newsom, to rethink the plant’s closure. Diablo Canyon is the state’s largest single source of emissions-free power and seen by some observers as vital to meeting evening peak demand when the more than 26GW of California’s commercial and residential solar power production drops off.
Keeping the plant online, however, would potentially raise the cost for floating wind development on the central coast, including in Morro Bay, where the Bureau of Ocean Energy Management (BOEM) recently
announced will lease up to 3GW of offshore wind acreage, along with 1.5GW of capacity acreage in the Humboldt wind energy area (WEA) in northern California.
“If Diablo Canyon is relicensed, PG&E’s three 500kV transmission pathways to
California’s electricity backbone will obviously be unavailable to support offshore wind,” Carl Wurtz, president of Californians for Green Nuclear Power, a local environmental activist group, told
Recharge. “Thus, the estimated $8.1bn needed to connect offshore wind in California will need to be expanded to accommodate the proposed Morro Bay wind farm.”
Floating wind plant in northern California would require $5.3bn-$8bn in high-voltage transmission lines, according to the California independent system operator (Caiso), compared to only a single, 500kV substation for around $110m for the central coast, assuming access to Diablo Canyon’s transmission infrastructure.
Larry Oetker, executive director of the
Humboldt Bay harbour district, being redeveloped to serve the offshore wind sector, told local California media recently: “If Diablo Canyon is still online, then the central coast is going to have the same transmission issues as the north coast
.”The state has yet to take a formal decision beyond the request to the DoE for an extension to the CNC programme application, and upgrading the 37-year-old plant to meet modern performance and operational standards would cost billions of dollars.
It is also calling for
multiple other grid-balancing solutions to be built, including the installation of 11.5GW of energy storage by 2026 and
long-range transmission cables to bring in more power from out of state as it strives to retire its gas-fired power plants. California already imports some 30% of its power needs, some of which is generated in coal-fired power plants.
The state has some 5.7GW of operational onshore wind plant, but the sector has historically faced widespread opposition from a variety of activists, which in part has prompted it the move towards deepwater offshore wind.
A study published by research house the Brattle Group last month, echoing an earlier report by MIT-Stanford universities, asserts that extending the operational life of DCPP by 20 years would enable California to achieve a carbon-free grid by 2035, earlier than the state’s legal mandate, at a cost $5bn lower than if the plant were retired, while reducing dependence on gas-fired power generation and lowering cumulative greenhouse gas emissions.
Despite this rising momentum to continue the nuclear power station’s operations, though, offshore wind developers who have expressed interest in Morro Bay’s three lease areas are confident that sufficient transmission capacity exists.
“Castle Wind’s view is that the availability of the Diablo Canyon [grid] facility is not necessary to develop and connect the three offshore wind leases of Morro Bay,” Marie Maitre, spokesperson for TotalEnergies, which is partnering with Trident Wind in the Castle Wind joint venture aiming to build in the Morro Bay acreage, told Recharge.
Caiso noted in its 2021-2022 Transmission Plan that the transmission system in the central coast area “can accommodate approximately 5GW-6GW of offshore wind generation interconnecting in the area of the DCPP that will be retiring by the end of 2025, and the Morro Bay area where gas-fired generation has retired”.
The California Energy Commission (CEC), the state energy policy agency,
based on the mandate of law AB525 that last year rubberstamped offshore wind development in state waters, is considering
targets of 3GW-5GW of floating wind by 2030, and as much as 50GW by 2045, while Caiso sees some 6GW of floating wind eventually off the central coast.
Should the the operational life of DCPP be extended, any conflicts with the floating wind sector are likely years away as the state faces multiple headwinds in developing the sector.
BOEM is only now beginning the multi-year leasing and permitting process, which will take at least eight to 10 years at a minimum for approval, while the state faces critical
port and supply chain bottlenecks and its
deep waters swiftly descending to more than 1,000 metres exceed the current capabilities of the nascent floating wind sector, leading experts to see lengthy delays to California’s offshore wind aspirations.
BloombergNEF (BNEF) stated in its first half 2022 report that
California is unlikely to have any floating wind before 2030, and sees the state deploying only 1.5GW as late as 2035.
Moreover, California has not firmly decided to seek life extension for DCPP, and PG&E spokesperson Suzanne Hosn only confirmed to Recharge: “At the governor’s request, PG&E has been assessing the option to extend operations of DCPP as the state continues its transition to a clean energy future.”
BOEM sees the US with a
clear opportunity to move swiftly to the front of the global floating wind pack, with director Amanda Lefton saying last year with “no clear dominance in [the sector], the US has the chance to become a leader in this early field”, while analyst group Aegir Insights reckons floating wind power
could account for as much as 25% of the total offshore plant capacity installed off US shores by 2035 fuelled by a massive build-out in Pacific waters.
