Monthly Archives: June 2017

Heavy seas engulf Rhode Islands Block Island wind farm, the first U.S. offshore wind warm. Photo by Energy.gov/Flickr

Offshore wind developments are rapidly expanding. But most wind turbines are not built to withstand a direct hit from the strongest hurricanes, according to a new study in Geophysical Research Letters that models the worst-scenarios caused by category-5 storms.

Researchers predict new offshore turbines would face hurricane wind gusts of more than 223 miles per hour but the turbines can only manage gusts of 156 miles per hour based on current engineering standards. Part of the problem: Offshore turbine designs often draw from onshore wind turbines in Europe, where hurricane conditions are essentially nonexistent.

We need to make sure offshore wind energy is successful the first time around, said Rochelle Worsnop, doctoral candidate at the University of Colorado Boulder, who spearheaded the project. We believe that this research can help guide those standards to help turbines placed in hurricane prone regions survive these major hurricanes.

Offshore wind energy development is growing along U.S. coasts. The first U.S. commercial offshore wind farm went into operation in December, and many more are on the horizon. Offshore wind energy generation could expand the nations energy supply with potential to provide 160,000 jobs and low-cost energy for millions of Americans, according to a government report.

Worsnop and her colleagues started this project by looking into where hurricane winds cross paths with offshore wind farms. At first, getting this kind of data proved nearly impossible.

Hurricanes that come within striking distance of offshore wind turbines are infrequent. Plus, at the moment, offshore wind developments are few and far between. Most wind measurements she could find in public databases were recorded too high above the water or too far from shore to reflect what a wind turbine might experience.

So, Worsnops team member George Bryan of the National Center for Atmospheric Research recommended she use a computer simulation driven by hurricane data from the last 15 years. Bryan used this high-resolution model to recreate the worst of the worst a category-5 hurricane eyewall, where winds can exceed 220 miles per hour to see how wind turbines would hold up. The team also investigated how wind characteristics, such as changes in direction and turbulence, might affect turbines.

Researchers found the extreme wind speeds they modeled would cause structural damage to wind turbines and possible failure of turbine parts. When wind speeds from typhoon Usagi in southern China exceeded turbine specifications in 2013, for instance, blades bent and towers toppled over.

Large and fast changes in wind direction could be problematic too, based on Worsnops model. Wind turbines work best when facing directly into the wind, so turbine rotors swivel about the tower to maintain a wind-in-the-face orientation. The researchers found most turbines would not twist fast enough to respond.

We are learning more about the anatomy of a hurricane, which is improving the design resilience of future wind turbines, Walt Musial, an engineer at the National Renewable Energy Laboratory and a senior author on the study, told NewsHour via email.

Their model also predicted wind direction changes up to 55 degrees between the ground and the tip of a blade a measurement called veer. As a result, these category-5 winds could bend a turbine blade in one direction say, at the tip as it simultaneously applies stress on another portion, causing the blade to malfunction or break.

One of the benefits of this study is that you can get a much better global, spatial quantification of that veer and thats fabulous, thats exactly what a wind turbine designer needs, said Sandy Butterfield, chairman of the International Electrotechnical Commission Renewable Energy (IECRE), the organization that writes the standards for wind turbines and other renewable energy equipment.

The researchers behind the study are now guiding a revamp of turbine engineering standards. Musial said they may take three years to implement.

The simulation is the best estimate we have. Its more accurate than any other estimate for the kinds of winds that could really damage a wind turbine, Butterfield, who was not involved in the study, said. Its going to help us update the standards to reflect wind turbine design criteria for hurricanes.

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Why offshore wind turbines can't handle the toughest hurricanes - PBS - PBS NewsHour

A widely used method to find oil and gas for offshore drilling can kill tiny sea creatures that are key for feeding many marine animals like shellfish, fish, and even whales. And the impacts on these tiny, drifting creatures called zooplankton are seen in an area much larger than previously thought.

The study, published in the journal Nature Ecology and Evolution, adds to the body of evidence that the loud noises produced during oil and gas exploration can disrupt marine life including whales that use sound to communicate and look for food. It also comes just a few months after President Donald Trump has signed an executive order looking to expand offshore gas and oil drilling in the Atlantic and Arctic oceans.

louder than a Saturn V rocket during launch

Oil and gas companies looking for offshore natural resources use seismic airguns to blast compressed air through the water and into the seafloor. The noise produced by these airguns is louder than a Saturn V rocket during launch, according to Nature. So researchers wanted to see what the effects are on the seas base of the food chain, the zooplankton.

The researchers blasted airguns in the ocean off southern Tasmania, and checked zooplankton populations before and after by using sonar and nets. The abundance of these tiny creatures dropped by 64 percent within one hour of the blast, the study says. Two to three times as many zooplankton were also found dead and the impacts were recorded as far away as 0.7 miles. Scientists previously estimated that impacts would occur only within 33 feet from the blast.

Its not 100 percent clear how the airguns are causing the die-offs, but its possible the blast throws off the receptors the animals use to navigate, disorienting them and causing them to die, according to Nature. Because zooplankton is key for feeding larger marine animals, the die-offs could have serious cascading effects.

"Plankton underpin whole ocean productivity," lead author Robert McCauley, an associate professor at Curtin University in Australia, said in a statement. "Their presence impacts right across the health of the ecosystem so it's important we pay attention to their future."

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The hunt for offshore oil is killing tiny sea creatures that are key for healthy oceans - The Verge

Recently unveiled plans for an offshore wind farm in the Australian state of Victoria face a major hurdle: onshore projects are far, far cheaper.

Right now, in Australia its a very competitive price market, said Robert Liew, senior analyst for Asia-Pacific at MAKE Consulting, which is owned by GTMs parent company Wood Mackenzie. The price of onshore wind is even more competitive than, say, a new-build coal project.

Onshore projects are delivering power at between USD $0.45 and $0.56 per megawatt-hour, he said. Offshore wind in Australia might struggle to come in at twice that level.

In Europe, offshore wind is getting close to Australias onshore price range because countries such as Germany and the U.K. have spent decades building an industry to support their projects. Europe also boasts several major offshore wind turbine manufacturers.

But the lack of native turbine-makers or an established supply chain makes it hard for offshore generation to come anywhere close to the price of onshore projects in Australia.

Nevertheless, Victorias government this month welcomed a proposal from Offshore Energy, a little known developer, to carry out a feasibility study for a 250-turbine project between 10 and 25 kilometers off the coast of Gippsland, in the southeast of the state.

A new renewable power generator of this size would drive down electricity prices, and well support offshore energy wherever we can to progress this study, said Victorias Minister for Energy, Environment and Climate Change, Lily DAmbrosio, in a press release.

If the AUD $8 billion (USD $6 billion) project goes ahead, It is hoped the wind farm could be generating power in time to contribute to the Labor Governments Renewable Energy Target of 40 percent by 2025, the press note said.

Its a big "if," though.

Jack-up barges, which are just one vital element of the offshore wind supply chain, can cost $165,000 a day. There are almost certainly none in Australia, nor, quite possibly, in the whole of the southern hemisphere.

If a barge has to be chartered all the way from Europe, along with all the other vessels needed for construction, support, cable-laying and more, and the turbines and other components also have to be shipped around the world, Its going to be difficult to get the cost down, said Liew.

Onshore wind, in contrast, is cheap and easy. The average size of onshore wind farms in Australia is 130 megawatts, and the projects have capacity factors of between 35 percent to 45 percent.

Add in the low cost of plots in Australias vast open landscape, and the country emerges as one of the best places on the planet to build onshore wind farms. Whether offshore can offer better value is the million-dollar question, Liew commented.

And its not just costs that could pose a problem for offshore wind in Australia.

According to Robert Bates, assistant underwriter at the renewable energy insurer GCube, Earthquakes and cyclones, while infrequent in Australia, are natural-catastrophe-type risks that developers in Australia offshore wind may have to contend with.

The seabed surrounding Australia is diverse and complex, he said. Moreover, different soil types require different foundation types. Detailed geotechnical studies will be crucial in determining what will be best for each site.

Finally, given that there are more than 1,100 offshore oil and gas platforms around the country, safely circumnavigating existing marine infrastructure is especially challenging.

Australia does not appear likely to gain an industrial advantage by planting turbines off Gippsland. It has no original equipment manufacturers that would benefit, or nearby markets to exploit.

That said, it is too early to completely write off the prospect of Australian offshore wind. Liew said he spoke to developers curious about investigating offshore projects in the country.

Australia also has a history of welcoming foreign companies to build infrastructure projects, he said. And with high electricity prices, there might be an opportunity to introduce technologies that would not be viable elsewhere.

Finally, the timeframe for the Gippsland project may leave enough room for further cost reductions. Beyond 2020, a low-cost offshore supply chain might be accessible from Asian markets such as Japan or South Korea.

Turbines, meanwhile, might be supplied by firms such as Siemens, Vestas or Senvion, which already have a significant presence in the Australian onshore market.

I wouldnt rule it out, said Liew. Maybe the conditions [in Gippsland] are just perfect. But its a real tough sell.

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The Big Problem Facing Offshore Wind in Australia - Greentech Media

Greece has approved an application by a consortium of ExxonMobil, Frances Total SA, and domestic oil refiner Hellenic Petroleum, to drill for oil and gas off the island of Crete, Reuters reported on Friday, quoting the Greek energy ministry as saying.

Greece has also approved another application, by local company Energean Oil, to start drilling for oil offshore western Greece.

The countrys oil and gas resources management body will launch a tender for exploration licenses in the blocks by the end of June, with the goal to award licenses by the end of this year.

Last month, the energy ministry held talks with Exxon and Total to discuss the potential of offshore gas exploration. Back then, a government official told Reuters that a consortium of ExxonMobil, Total, and Hellenic Petroleum was expected to file an application to explore south of the island of Crete.

Greece, which has been struggling with a severe debt crisis in the past few years and has received billions of euros of EU- and IMF-backed bailout support, is trying to resume efforts to search for hydrocarbons both onshore and offshore and possibly lessen its dependence on energy imports in the future.

In October last year, Greeces energy ministry named a consortium led by Total SA and comprised of Italys Edison and Hellenic Petroleum as the preferred bidder to drill for gas in an offshore block in the Ionian Sea west of the country.

Related:Underperforming Energy Sector May Soon See M&A Wave

The head of the Hellenic Hydrocarbons Resources Management (HHRM), Yannis Bassias, said last month that the country would start opening new onshore oil and gas blocks for exploration in 2018.

As of next year, and perhaps earlier, we will begin announcing that we are opening the door to whoever is interested in onshore sites, according to the head of Greeces oil and gas resource management body.

By Tsvetana Paraskova for Oilprice.com

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Greece Okays Exxon-Total Bid To Explore For Offshore Oil - OilPrice.com