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Written by: Matthew Lackner, UMass Amherst

Published: 09 December 2022

 

Northern California has some of the strongest offshore winds in the U.S., with immense potential to produce clean energy. But it also has a problem. Its continental shelf drops off quickly, making building traditional wind turbines directly on the seafloor costly if not impossible.

Once water gets more than about 200 feet deep – roughly the height of an 18-story building – these “monopile” structures are pretty much out of the question.

A solution has emerged that’s being tested in several locations around the world: wind turbines that float.

In California, where drought has put pressure on the hydropower supply, the state is moving forward on a plan to develop the nation’s first floating offshore wind farms. On Dec. 7, 2022, the federal government auctioned off five lease areas about 20 miles off the California coast to companies with plans to develop floating wind farms. The bids were lower than recent leases off the Atlantic coast, where wind farms can be anchored to the seafloor, but still significant, together exceeding US$757 million.

So, how do floating wind farms work?

Three main ways to float a turbine

A floating wind turbine works just like other wind turbines – wind pushes on the blades, causing the rotor to turn, which drives a generator that creates electricity. But instead of having its tower embedded directly into the ground or the seafloor, a floating wind turbine sits on a platform with mooring lines, such as chains or ropes, that connect to anchors in the seabed below.

These mooring lines hold the turbine in place against the wind and keep it connected to the cable that sends its electricity back to shore.

Most of the stability is provided by the floating platform itself. The trick is to design the platform so the turbine doesn’t tip too far in strong winds or storms.

There are three main types of platforms:

• A spar buoy platform is a long hollow cylinder that extends downward from the turbine tower. It floats vertically in deep water, weighted with ballast in the bottom of the cylinder to lower its center of gravity. It’s then anchored in place, but with slack lines that allow it to move with the water to avoid damage. Spar buoys have been used by the oil and gas industry for years for offshore operations.

• Semisubmersible platforms have large floating hulls that spread out from the tower, also anchored to prevent drifting. Designers have been experimenting with multiple turbines on some of these hulls.

• Tension leg platforms have smaller platforms with taut lines running straight to the floor below. These are lighter but more vulnerable to earthquakes or tsunamis because they rely more on the mooring lines and anchors for stability.

Each platform must support the weight of the turbine and remain stable while the turbine operates. It can do this in part because the hollow platform, often made of large steel or concrete structures, provides buoyancy to support the turbine. Since some can be fully assembled in port and towed out for installation, they might be far cheaper than fixed-bottom structures, which require specialty vessels for installation on site.

Floating platforms can support wind turbines that can produce 10 megawatts or more of power – that’s similar in size to other offshore wind turbines and several times larger than the capacity of a typical onshore wind turbine you might see in a field.

Why do we need floating turbines?

Some of the strongest wind resources are away from shore in locations with hundreds of feet of water below, such as off the U.S. West Coast, the Great Lakes, the Mediterranean Sea and the coast of Japan.

The U.S. lease areas auctioned off in early December cover about 583 square miles in two regions – one off central California’s Morro Bay and the other near the Oregon state line. The water off California gets deep quickly, so any wind farm that is even a few miles from shore will require floating turbines.

Once built, wind farms in those five areas could provide about 4.6 gigawatts of clean electricity, enough to power 1.5 million homes, according to government estimates. The winning companies suggested they could produce even more power.

But getting actual wind turbines on the water will take time. The winners of the lease auction will undergo a Justice Department anti-trust review and then a long planning, permitting and environmental review process that typically takes several years.

Globally, several full-scale demonstration projects with floating wind turbines are already operating in Europe and Asia. The Hywind Scotland project became the first commercial-scale offshore floating wind farm in 2017, with five 6-megawatt turbines supported by spar buoys designed by the Norwegian energy company Equinor.

Equinor Wind US had one of the winning bids off Central California. Another winning bidder was RWE Offshore Wind Holdings. RWE operates wind farms in Europe and has three floating wind turbine demonstration projects. The other companies involved – Copenhagen Infrastructure Partners, Invenergy and Ocean Winds – have Atlantic Coast leases or existing offshore wind farms.

While floating offshore wind farms are becoming a commercial technology, there are still technical challenges that need to be solved. The platform motion may cause higher forces on the blades and tower, and more complicated and unsteady aerodynamics. Also, as water depths get very deep, the cost of the mooring lines, anchors and electrical cabling may become very high, so cheaper but still reliable technologies will be needed.

But we can expect to see more offshore turbines supported by floating structures in the near future.

This article was updated with the first lease sale.

Matthew Lackner, Professor of Mechanical Engineering, UMass Amherst

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Written by: LAKE COUNTY NEWS REPORTS

Published: 08 December 2022

LAKE COUNTY, Calif. — This week several local tribes and an environmental group that has advocated for protections for the Clear Lake hitch asked the U.S. Fish and Wildlife Service to provide emergency protections to the fish.

The Big Valley Band of Pomo Indians, Robinson Rancheria of Pomo Indians, Habematolel Pomo of Upper Lake, the Scotts Valley Band of Pomo Indians and the Center for Biological Diversity are seeking the help for the hitch, a native minnow found only in Clear Lake.

Separately, the tribes are holding a summit with state and federal agencies on Thursday to discuss immediate protections with the state, said Sarah Ryan, the environmental director and emergency management director for the Big Valley Pomo.

This week’s request under the Endangered Species Act notes that the imperiled California fish’s numbers have plummeted in recent years. Extinction is now a distinct possibility if swift action isn’t taken.

The hitch has great cultural significance and has been a primary food source that has sustained the Tribes for generations.

“Our tribe expects and relies on the state and federal agencies to carry out their responsibilities for managing land, water, and all the fish and wildlife,” said Philip Gomez, chairman of the Big Valley Band of Pomo Indians. “We have come to a point where we know that the agencies must try harder, and they must welcome the Tribes to co-manage our land and waters. We call out to Secretary of the Interior Deb Haaland to authorize emergency listing of the chi/Clear Lake hitch immediately, so they can be protected for their spawning a few months from now. None of us want this fish to go extinct on our watch, as tribal leaders.”

“We are talking about extinction,” said Meg Townsend, senior freshwater attorney at the Center for Biological Diversity. “The hitch can’t withstand one more year of failed spawning. The Fish and Wildlife Service’s failure to protect this severely imperiled fish for more than a decade is shocking and unacceptable. Only emergency protections can correct this grievous error and give the hitch a fighting chance.”

The last successful spawning of Clear Lake hitch was observed in 2017. The following year, extremely few juvenile hitch were collected. Almost no juvenile hitch have been observed since. Adult hitch are now also in steep decline. With an estimated six-year lifespan, the hitch can’t survive many more years of failed spawning without disappearing forever.

The primary threat to Clear Lake hitch is a lack of spring flows in lake tributaries used for spawning. This is caused by water over-withdrawal, both legal and illegal, that is being worsened by climate change-driven drought. The hitch is also threatened by fish-passage barriers, habitat degradation, pollution, and predation and competition from invasive, stocked fish, including carp and bass.

The Center for Biological Diversity petitioned the Service in 2012 to protect the hitch under the Endangered Species Act. After eight years of delay and a lawsuit by the center, the agency finally issued a decision, but, in a bizarre move, denied the fish protections.

The center challenged this decision in federal court, leading the agency to reconsider listing the hitch, but no new decision will be made until 2025.

“As President Biden highlighted this week at the White House Tribal Nations Summit, Indigenous Knowledge is to be considered in policy and agency decision making,” said Sherry Treppa, chairperson of the Habematolel Pomo of Upper Lake. “The service needs to respect not only Tribal Nations but the president and take immediate action otherwise years of research, preservation and repopulation efforts by local tribal nations and county will be for naught.”

“The Clear Lake hitch — the chi — is an important part of our tribe’s culture that sustained our families for generations,” said Jesse Gonzalez, vice chair of Scotts Valley Band of Pomo Indians. “We as Indian people have lost so much of our ways and our culture at the hands of others, and now we’re trying so hard to hold on to what’s left, for ourselves, for our families, and for our future. I remember catching chi as a young boy and now can only hope that my children will one day have that same experience. If the U.S. Fish and Wildlife Service doesn’t give the chi emergency endangered species protections, we fear that our future generations will never have that opportunity.”

The hitch needs immediate action, including captive rearing, enforcement action against illegal water withdrawals by cannabis growers and others, control of invasive predatory fish in the lake, and work with legal water rights holders to maintain instream flows. Emergency protection under the Endangered Species Act would help ensure these things happen.

On Nov. 3, the California Fish and Game Commission took the unprecedented step of writing to the Service to request emergency listing of the hitch under the act.

The service has only given emergency listings to two species in the past two decades. Such listings take effect immediately upon publication in the Federal Register and last for 240 days. Simultaneously, the service must publish a proposed rule to extend the listing beyond the initial period.

“The Clear Lake hitch is on the verge of extinction unless action is taken now,” said Michael Y. Marcks, vice-chairperson of the Habematolel Pomo of Upper Lake. “Tribes are united in seeking protection of the hitch, which is culturally significant to The Habematolel Pomo of Upper Lake. Our tribe has strong connections and traditions to our land, and we constantly strive to conserve, preserve, and protect all our natural resources. The U.S. Fish and Wildlife Service must use its emergency authority to protect and preserve the hitch for future generations.”

“In 2004, Robinson Rancheria started the efforts for the first petition to U.S Fish and Wildlife for the hitch to be listed under the Federal Endangered Species Act,” said Irenia Quitiquit, secretary treasurer of the Robinson Rancheria of Pomo Indians Citizens Business Council. “Because of Robinson Rancheria’s peoples’ strong ties to the hitch, culturally and for subsistence, an emergency listing would be a great victory toward saving the hitch from extinction. Robinson Rancheria’s Tribal efforts over the past 18 years has been documented through many federal grants and tribal support efforts to continue studying the hitch. Research has proven to be effective in this hopeful goal — having the hitch listed as a federally endangered species. All Lake County California Tribes look forward to continuing the meaningful work to save the hitch.”

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Written by: Elizabeth Larson

Published: 08 December 2022

LAKE COUNTY, Calif. — Lake County’s interim Public Health officer on Tuesday updated the Board of Supervisors on seasonal illnesses and the winter outlook.

The California Department of Public Health said this week that statewide flu activity has reached high levels across the state.

Dr. Karl Sporer told the supervisors that flu activity also is rising in Lake County, along with COVID-19.

He noted that he had last visited the board two months ago to say how nice everything was. “Now, it’s not so nice.”

Sporer said health officials are seeing a “triple epidemic” involving flu, COVID-19 and respiratory syncytial virus, or RSV.

“We’re holding our own at the two hospitals,” he said.

RSV is causing a lot of pediatric hospitalizations nationwide. However, Sporer — who noted county health officials meet with the two hospitals every two weeks — said there have only been two RSV patient cases that needed to be transferred out and they were able to find rooms for them.

“It hasn’t impacted our community at this point,” Sporer said.

Sporer said he thinks RSV will peak in the next couple of weeks and then it will go down.

At the same time, Sporer said probably one of the worst flu seasons in 15 years is now taking place, and he’s recommending people get vaccinations.

The flu is causing a 25% increase across admissions in hospitals, Sporer said. “We’re going to see some strain here as we get into the new year.”

At the same time, he is starting to see a 10 to 15% increase in COVID-19 and coronavirus across the country, and more people are being admitted to hospitals with the illness.

He said he’s concerned about the flu and COVID together, causing hospitalizations to go up.

Sporer doesn’t expect the situation to get as bad as it was in New York City three years ago, “But I think it’ll be a tough winter to get through.”

He said the county will work with the local hospitals to get through the situation.

The county also is working with the state, with Sporer noting that the state’s COVID state of emergency will end at the end of February.

During the discussion, Supervisor Jessica Pyska said that Adventist Health is opening an urgent care clinic the second week in January. It will be the only such clinic in Lake County.

Supervisor Bruno Sabatier asked about capacity at Lake County’s hospitals.

Sporer said they are seeing a little bit of an increase in interfacility transports out of the county.

There are eight intensive care unit beds in Lake County, two of which were empty as of Tuesday, he said.

“So we’re handling it at this point,” Sporer said.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it.. Follow her on Twitter, @ERLarson, or Lake County News, @LakeCoNews.