While more than 3,000 offshore wind turbines push electricity to power-hungry Europeans, the number of towering turbines in U.S. waters is precisely zero. But that’s about to change.
The first U.S. offshore wind farm is slowly rising in the Atlantic Ocean south of the state of Rhode Island and east of New York’s Long Island. It could be up and running by the end of 2016, according to media reports.
The five-tower farm is small in scale and enormous in price: the $290 million project will provide energy to 1,000 year-round residents of a remote tourist stop called Block Island, where energy costs are extremely high because the island is more than 10 miles from the mainland. Developers of the project hope it will establish a toehold for offshore wind energy in the United States.
Once this project starts delivering power, it may be able to provide insights on economies of scale that will enable an industry to take root on the Eastern Seaboard. The relatively shallow Atlantic Shelf provides the only viable choice for the U.S. because the Pacific Shelf hugs the coastline and drops off sharply, making the waters are far too deep for wind farm development.
The large offshore wind farms of Europe rely on government subsidies and policies designed to push more and more European energy consumption into the green-energy sector, but such policies are far more rare in the United States. While investors have made wind turbines a common sight across the broad open plains of the nation’s interior, finding folks brave enough to try the untested waters of offshore wind energy in the U.S. another matter altogether.
High up-front costs, investor skepticism and lack of public-sector support equal slow going for offshore wind the U.S. Low fuel prices also are discouraging development of renewable energy sources. But eventually, hydrocarbon costs will rebound and make these kinds of projects more attractive.
The five towers of the Block Island project will be 600 feet high and designed to withstand a category 3 hurricane. Because the winds are stronger at higher altitudes and farther away from shore, wind farm developers have an incentive to build taller towers in ever-more-remote locations. The Block Island towers must be installed on platforms that sit on the seabed in several hundred feet of water — dramatically adding to the project’s costs. In the decades to come, floating platforms anchored to the seabed may provide a much more economical base for offshore wind energy projects.
Whatever the future holds, we’ll be providing the durable cable hardware that enables the offshore wind energy industry to transmit energy to people on land.
More on the Block Island project:
• First US Offshore Wind Energy Projects Could Deliver Jolt Of Momentum To Struggling Sector
• America’s First Offshore Wind Farm Quietly Takes Shape
Fundy Bay is famous for pictures of fishing boats tilted on their hulls — run aground by the immense power of the world’s largest tides.
The waters of this scenic coastal inlet along Canada’s Nova Scotia and New Brunswick provinces rise and fall by more than 50 feet twice a day, every day of the year. That predictability is one of the key reasons why green-energy researchers are fascinated with the potential of converting tidal movements into electricity. Solar power goes dark after sunset and wind power rises and falls with moving weather patterns. But tides rise and fall like clockwork, creating the potential for an extremely reliable stream of electric power.
The Trouble with Tidal Energy
Unfortunately, the ocean is one of the worst places on earth to install mechanical equipment. Saltwater is extremely corrosive, and working on machinery underwater is incredibly dangerous and expensive.
Some wave and tidal energy projects are mounting turbines on the sea floor. This keeps the turbines out of sight, which is a boon to coastal views, but it also dramatically increases the costs of upkeep precisely because they are so difficult to access.
Floating Platforms: A Tidal Energy Alternative
Fundy Bay’s epic tides have made it a hub for working out these kinds of challenges in wave and tidal energy research. One alternative researches are exploring is mounting a turbine beneath a floating platform that’s moored to the ocean floor via cables. A turbine connected to a floating platform could have all of its machinery easily accessible from the platform rather than mounted on the sea floor, where the only way to reach it is with scuba divers or remote-operated vehicles (or both).
In March 2016, a Canadian firm called Dynamic Systems Analysis (DSA) helped launch a floating research platform called EcoSPRAY that will document how highly turbulent tides work. This, in turn, will provide clues to the best ways to deploy floating tidal energy platforms that have been moored to the ocean floor.
The platform is operating in the Grand Passage between Freeport and Westport, Nova Scotia, in the Outer Bay of Fundy. Sensors on the EcoSPRAY will track wind speeds, tidal currents and wave actions. A drag plate mounted on the bottom of the platform will simulate the thrust of an underwater turbine, DSA says.
Protecting tidal ecosystems
While floating tidal power platforms would be less visually pleasing than turbines mounted on the sea floor, they have the potential to be less disruptive to underwater environments. Mounting an underwater turbine is a major construction project, whereas placing anchor points on the sea floor for mooring cables could be far less disruptive to the coastal environment.
Protecting that environment is very much on the minds of Fundy Bay researchers. Fundy Ocean Research Center for Energy (FORCE), the Offshore Energy Research Association (OERA) and the Nova Scotia Department of Energy are all working together on a half-million-dollar program to determine the effects of tidal energy turbines this year.
This points to the future of wave and tidal energy, which may well depend on finding the best mix of high energy output, low cost and minimal impact on the subsea environment.
A trade association representing the subsea cable industry in the United Kingdom widened its focus in March 2016 to cover all of Europe.
The new European Subsea Cables Association (ESCA) takes the place of Subsea Cables UK. The trade group provides a forum for people who own, manage or service subsea telecommunication and power cables or serve the subsea cable industry in Europe and its surrounding waters.
ESCA’s prime goal is to encourage marine safety and help protect subsea cables from hazards such as fish nets, ship anchors and submarine landslides. The group also will defend the rights of operators to install and maintain underwater cable solutions.
“The requirement to form this new association has come from our membership and it was the logical evolution of the organization,” said Peter Jamieson of Virgin Media, chairman of the European Subsea Cables Association. “Close to 50 percent of the old UK association members were non-UK. Therefore, we can better serve our members by becoming a more regional association. ”
ESCA Executive Committee member Colin Rayman of Red Penguin Associates said that creation of the Europe-wide association will make it easer to confer with European maritime and fishing industry officials and government regulators “to move closer to attaining mutual understanding of our industries, sharing the seabed safely and maintaining the integrity of assets.”
The association will give its members advice and technical papers that will help everybody in the sector go about their business. Members of ESCA are experts in all phases of the subsea cable industry. They’ll convene bi-annually to share ideas and information.
If you’re in the submarine cable business, whether you’re an owner, operator, consultant, or subsea cable hardware supplier, you’re welcome to stop by the organization’s website at www.escaeu.org and download an application to join.
At PMI, we’re glad to see these people coming together to foster the health of the subsea cable industry across the European continent. Developments like tidal power and subsea power grids need consensus among business people and regulators to develop standards and hone technical expertise vital to the sector’s future.
As a premier provider of subsea cable hardware, we’re also on the front lines of Europe’s efforts to switch more of its energy consumption to renewable sources like wind power.
A new ship in the fleet of Petroleum Geo-Services (PGS) suggests low oil prices haven’t closed the spigot of innovation in deep ocean engineering.
A naming ceremony in Nagasaki, Japan, in mid-March celebrated PGS’s acquisition of the Ramform Tethys, a new seismic data acquisition ship that’s brimming with the latest 3D and 4D technology for seismic projects that bounce sound waves off the sea floor to find untapped supplies of crude oil.
Built by Mitsubishi Heavy Industries Shipbuilding at a cost of $285 million, the Tethys is the third Ramform Titan-class vessel in the PGS fleet; the first two were finished in 2013-2014 and the fourth will come to sea in 2017. Titan-class ships have a distinctive triangular hull that’s 104 meters long and 70 meters wide at the stern — the widest hulls currently at sea, PGS says. The extra-wide stern looks a bit odd on the sea, but it has huge benefits for towing streams of sensor arrays and providing extra stability for the crews scanning the data pouring in from those arrays.
“The Ramform Tethys like her Ramform Titan-class sisters is well adapted to the prevailing economic environment,” PGS says on its website. “Her operational cost per streamer is the lowest around, while the resolution and reliability of the dual-sensor, broadband GeoStreamer data she produces is by far the best currently available.”
The Titan-class ships in the PGS fleet use an impressive amount of underwater cable hardware. The Tethys can carry 24 streamer reels: 16 reels aligned abreast and 8 reels further forward, with capacity for 12-kilometer streamers on each reel. That enables an array with hundreds of thousands of sensors spread over an area of 12 square kilometers — nearly 3,000 acres or more than triple the size of New York’s Central Park.
The new ship makes it faster and easier to deploy and retrieve cable hardware for subsea explorations. That allows surveys to be completed much sooner and ships to stay at sea longer in the calm times between ever-present storms on the high seas. That equals greater efficiencies that can be passed along to PGS clients.
“Productivity, safety, stability and redundancy are the key benefits of these vessels,” said Per Arild Reksnes, executive vice president for operations at PGS, which is based in Norway. “Their ability to tow many streamers gives high data quality with dense cross-line sampling and cost-efficient acquisition with wide tows.”
The Ramform Tethys has six engines producing 26.4 megawatts of power, and carries over 6,000 tons of fuel and equipment. The fact that companies are still buying ships of this size and complexity demonstrates that even with severe economic challenges across the oil sector, people will still see the wisdom of investing in better technology.
Discover how other Oil & Seismic companies are finding ways to save on fuel and cost in our Free Hydrodynamic Efficiency report.
The offshore wind industry has fresh guidance on using reliable standards to determine the best depth for burying offshore wind farm cables.
In February 2016, the Offshore Wind Accelerator based in the U.K. published advice to offshore wind farm operators to help them ensure they are burying their power cables at a safe depth. This is a serious concern because power cable damage is one of the most common costs that threaten the success of offshore wind farms.
The advice is in the “Application Guide for the Specification of the Depth of Lowering using CBRA.” CBRA means “Cable Burial Risk Assessment Guidance” — which uses predictive modeling to help offshore wind operators get a greater handle on the risks of offshore cable burial. The hope is that CBRA will help the entire industry thrive by addressing the need for reliable, consistent cable-burial practices that are the standard across the industry.
Standardized offshore cable burial also can help fishing fleets, shipping lines and offshore oil developers reduce the risk that their operations will damage the cables tethered to offshore wind farms. Read more on the promise of new CBRA guidance in this update from Maritime Journal.
As a leading provider of subsea equipment, PMI is helping the offshore wind power industry address its cable safety concerns. Contact us for the facts on offshore wind cable hardware designed to withstand the rigors of the deep sea.
Have questions about your offshore wind power cables? Need tips on how to extend the life of your subsea cables? PMI has the answers – check out our free guide to Extending the life of you subsea power cables:
Perhaps, though it’s probably a decade away. A recent article in the Virginian-Pilot of Norfolk, Virginia, explained that scientists are studying the waters off Cape Hatteras, North Carolina, one of the most powerful flow points in the Gulf Stream, to see if there is a way to harness that energy.
Figuring out how to do that would be a triumph of offshore energy engineering. While ocean wave energy is considered a promising source of renewable power, drawing energy from individual currents within our oceans is still mostly an idea on the drawing board.
The Virginian-Pilot article sounds a note of caution: “So far, no commercially connected turbines operate in the Gulf Stream, according to the Bureau of Ocean Energy Management. A few prototypes have been tested off the coast of Florida. Challenges include turbine maintenance in a harsh, salty environment and long distances to run cable connections.”
One expert quoted in the article said the Gulf Stream’s flow is strong enough to power all of North Carolina (population 9.5 million) and more. That’s makes sense, given that the Gulf Stream transports more water per second than all the world’s rivers combined, according to National Oceanic and Atmospheric Administration.
At PMI, we are monitoring all the developments in marine renewable energy. Companies are already proposing turbines for inland rivers, so it stands to reason that ocean current development could follow in that path. As these technologies advance, we’ll be poised to provide tough, durable cable hardware to ensure that power finds its way to land safely.
The offshore wind industry made significant strides in Europe last year, according to the European Wind Energy Association (EWEA). This growth has broad implications both for the renewables industry and the subsea cable market.
EWEA’s “Wind in Power: 2015 European Statistics” report published in February 2016 said European offshore wind installations more than doubled in 2015 from the year before. Germany had by far the most wind-power activity in 2015, adding 6,013 megawatts of generating capacity — and 38.4% of that was offshore.
Offshore wind installations accounted for 33.4 percent of all installations in 2015, according to EWEA’s data, up from 13.7% year before. Furthermore, investments in wind power hit an all-time high in 2015, EWEA said, with offshore wind leading the charge.
“Financial commitments in new assets reached a total of €26.4 billion, a 40 percent increase from 2014,” the report said. “While investments in new onshore wind generating assets increased by 6.3% in 2015, those in the offshore wind sector doubled compared to the previous year.”
A summary of the report in the website OffshoreWIND.biz notes where most of the capacity was added in 2015:
- Germany: 2,282 megawatts (75.4%), a four-old jump from the year before
- UK: 566 MW (18.7%)
- Netherlands: 180 MW (5.9%)
Another EWEA report, “The European Offshore Wind Industry — Key Trends and Statistics 2015,” drills deep into the details of the continent’s offshore power industry. It notes that “total investments for the construction and refinancing of offshore wind farms and transmission assets hit a record level of €18 billion.”
At PMI, we’re watching the growth of offshore wind closely because it has the potential to affect all the players in the subsea cable market. After all, those wind turbines depend on offshore cables to transmit power back to the mainland (the average turbine site was 43.3 kilometers from shore in 2015, in 27.1 meters of water). As sites near shore become more fully developed, offshore sites will inevitably move farther away and into much deeper water.
Those developments mean offshore cables and equipment like subsea cable terminations will need to be extremely tough and reliable — the two signature qualities of PMI cable equipment.
The coast of Scotland has some of the world’s strongest waves, which makes it a vital testing ground for wave turbines that convert wave movements into electricity.
So it’s no surprise that the Pentland Firth region of the Scottish coast is the site of the $1.5 billion MeyGen turbine project, where offshore cables are being laid in the opening phases of an initiative that aims to install 279 wave turbines below the surface of the ocean. As a recent Quartz.com report noted, the project could provide up to 400 megawatts of electric juice that could power 175,000 homes.
The wave-power turbines look much like wind-power turbines. Moving waves turn the turbine blades, generating electric power. Some observers say wave-power technology is about three decades behind wind power. But the MayGen project could signal the arrival of wave technology power, once it gets up and running.
Wave power technology is taking a wide array of shapes. Some devices look a bit like mechanical eels floating on the surface of the water; others are more like paddles that flow back and forth with the waves, moving a piston that generates power.
The ocean is an alluring power source, because it is so much denser than air and can therefore generate far more movement that can be converted into electricity. But even with 800 times more density than air at the surface, the water in the ocean creates an extremely problematic environment for energy development.
“People say this is not rocket science,” says Neil Kermode, managing director of the European Marine Energy Centre. “No. You fire a rocket into a nice, cold vacuum. We’re trying to do things in a salty, grit-filled electrolyte that’s got animals in it.”
Indeed, waves flow in multiple directions, unlike the wind, and the undersea environment could potentially be damaged by these kinds of projects. These and other factors vastly complicate wave-power generation.
Right now, cable-laying equipment is installing the offshore cables that will convey power to the people of Scotland after the wave turbines are up (well, down) and running. While power cables may not seem as exciting as subsea turbines, they still represent one of the most vital components of the project.
As wave power advances, PMI will be poised to provide durable ocean cable hardware to help these kinds of projects succeed. We have the experience and knowhow to design and manufacture rugged cable accessories that can last for years in the most difficult ocean environments. As the energy world transitions from fossil fuels to renewables, PMI cable hardware will be there every step of the way.
Elsewhere on the PMI blog: Tidal and Wave Energy Industry Struggles With Harsh Ocean Environments
Related article at Environment360 published by Yale University: Will Tidal and Wave Energy Ever Live Up to Their Potential?
Subsea power grids require two major kinds of ocean equipment: subsea power cables to convey electricity to the grids, and generating equipment to distribute electricity to pumps and other devices required to find and extract crude oil.
Even in a time of depressed petroleum prices, oil companies still value deep ocean engineering and they like the prospect of placing power grids on the sea floor because the grids improve the efficiency of the extraction process, which helps hold the line on production costs. When the oil market inevitably rebounds, companies with the most efficient production processes will reap the greatest rewards.
Let’s look at some of the ocean hardware that will go into these subsea systems:
- Transformers: These take power from the surface — either from the mainland or a floating platform — and convert it into the voltage needed at the undersea grid level.
- Switch gear: Switches adjust the flow of electricity to the deep-sea components that need it. If a pump needs different voltage than a compressor, switch gear takes care of that job.
- Variable-speed drives: An oil-drilling pump needs to run at multiple speeds to achieve maximum efficiency. VSBs make this happen.
- Cables: Cables carry energy from the surface to the grid and distribute it to the transformers, switch gear, variable-speed drives and any other ocean hardware in the grid.
Why deep-sea power grids are so attractive
Oil drillers need a lot of power to extract oil from below the deep sea. A deep-sea power grid allows power to be distributed to dozens of pieces of subsea hardware across a wide expanse of the sea floor.
A site developing a deep-sea oilfield becomes much easier to operate if power sources are on the sea floor near the point of extraction. Without a grid, power can be sent down via cables to equipment within a very limited expanse. A grid dramatically expands the area of sea floor that has available power.
Challenges for deep-sea equipment
Companies are designing subsea grids that can operate for up to 30 years in up to 10,000 feet of water. That places immense pressure on the equipment and requires precise engineering to protect delicate electrical components.
Saltwater is extremely corrosive, and undersea creatures like to attach themselves to any structures they can find. Fishing fleets drag deep nets that can become entangled in deep-sea equipment, and ship anchors have the potential to damage or cut subsea power cables.
Robust ocean equipment is the answer
Subsea energy companies understand the extreme terrain and know they need to build robust gear to provide reliable systems that can last decades. That also means they need to rely on proven ocean hardware that is high quality, highly reliable and fully flexible.
Offshore renewable energy solutions might be new to the world, but we know that all ocean equipment requires deep ocean engineering experience. And for over 60 years, PMI Industries has provided ocean hardware that increases efficiency, reduces failures, and improves installation and deployment time.
Waves and tides offer some of the most predictable, consistent, and just generally big energy resources available. However, rollouts of actual wave and tidal energy power installations have been slow. Part of the reason for this is that there is no consensus at all on what represents the best device designs to actually harness waves and tides and therefore on what subsea equipment is necessary to use.
Any subsea equipment needed to harness tidal energy is going to be expensive – and will tend to drive building costs to be anywhere between 3 to 15 million dollars and sometimes more. But in the long run, the investment will pay off.
Now the pros and cons of tidal energy always bring debate – but tidal energy has a lot going for it:
Consistent Power – Tides move constantly throughout the day, which provides a consistent stream of electricity generation capacity.
Pollution-Free – By taking advantage of only the tide, tidal power creates no greenhouse gas emissions or water pollutants.
Renewable – No material resources are used or changed in the production of tidal power, making it a truly renewable power form.
Minimal Visual Impact – Tidal power devices are fully or nearly completely submerged in water well offshore. This reduces the “damaging of water views” that has been associated with offshore wind turbines.
Efficient – Tidal Power converts roughly 80% of the kinetic energy into electricity, as opposed to coal and oil which convert only 30% of the energy held within.
Locations – There are numerous locations for tidal power around the world. Other websites online have this number at 40, however the coast of British Columbia, Canada has 89 alone.
And most importantly it offers low operating costs – Once installed, there are few ongoing operating costs or labor costs. By making investments at the forefront and building these systems properly with reliable equipment, tidal energy power plants offer a long lifespan, ultimately reduce costs, and make tidal energy more cost-competitive in the long run.