Who’s offshore?

Many companies exhibited their offshore inventory at the AWEA conference in Atlantic City earlier in October. Here’s a look at a few and what they have to offer.

Vestas V112 3.0-MW offshore turbine

The V112-3.0MW Offshore is designed to take full advantage of wind conditions at sea. It’s well suited for high offshore wind speeds and low turbulence and has the IEC IB offshore wind classification. It features what the company calls the GridStreamer, which has a permanent magnet generator to ensure wider opertaion range of the turbine and reduced loss of power, along with a full-scale converter that offers excellent grid support, reduced drive-train loads, and high energy productions over a greater range of wind speeds. Other features include:

-large rotor diam. (112 m), 54.65-m blades for high yield even at low (below 12 m/s) and medium wind speeds

-nacelle cover has the ability to close the integrated air intake holes and service hatches, and is 6.8 m installed (3.4 m for transport)

-The GridStreamer has the ability to continue to operate even during a severe grid voltage drop, converting excess power to heat and being able to quickly down-rate to 20%

-voltage range is 0.9-1.1 pu, frequency is 47-53 Hz, max short-circuit level 25kA, power factor range: 0.9 capacitive/0.83 inductive (HV transformer)

REpower 6M offshore turbine

REpower’s 6M offshore wind turbine stems from its 5M predecessor. The IEC IB class design is based on the company’s philosophies including conservative component design, ease of transportation, and grid compatibility. The turbine has a safety system including individually adjustable blades (electrically controlled), redundant temperature and speed sensing system, lightning protection, rotor holding brake with soft-brake function, and automatic fire protection system. Other features include:

-a power rating of 6,150 kW

-offshore cut-in wind speed of 14 m/s and cut-out at 30 m/s

-rotor diam. is 126 m, with fiberglass-reinforced plastic rotor blades 61.5 m

-hub height is 85-95 m (site specific)

-frequency is 50 Hz

Siemens SWT-2.3 and 3.6 offshore turbine

Rotor blades are made of fiberglass-reinforced epoxy and manufactured through what the company calls its Integralblade process. This means the blades are cast in one piece in a closed process, leaving no weak points at glue joints. An automatic lubrication system for major components of the nacelle (main shaft, gear box, and yaw system) enables continued operation even if maintenance is severely delayed by weather.  The offshore turbines are normally mounted on tubular steel towers fitted with internal hoists and comply with all relevant grid codes due to a NetConverter system that uses full conversion of the generated power. Other features of the 3.6 include:

-107-m diameter, blade length 52 m, and hub height 80 m or site specific

-3,600-kW generator with 690 V

-cut-in wind speed of 3-5 m/s and cut-out of 25 m/s

-NetConverter system is a modular arrangement for easy maintenance. Power is transferred by DC from rectifier installed in nacelle to inverter in tower bottom, minimizing cabling losses and avoided complications  from nacelle-mounted transformer

GE 4.0-110  offshore turbine

Growing from a 3-MW turbine in 2005, to a 3.5-MW model in 2007, GEdevelops its 4.0-MW offshore turbine in 2010. The turbine is built around a permanent magnet generator, delivering high efficiency at low wind speed. With direct-drive technology, the turbine removes the single most costly failure in offshore, gearboxes, and replaces it with reliable, slow-speed  components designed for the offshore environment. With a spacious nacelle and internal hub access, the IEC class turbine offers maintenance and safety advantages. Other features include:

-rotor diameter of 110 m

-cut-in wind speed of 3 m/s and cut out of 25 m/s

-At just 10 rpm, magnets at the rotor tip move at about 188 m/min. The generator’s 20 sections or modules allow replacing a portion of it without a complete removal of the 90-ton unit.

-Two main bearings transfer axial and bending loads from rotor to bedplate for higher reliability. The unit also sports continuous close-wind tracking to capture more energy.

-No yaw brakes or hydraulics.

Gamesa G11X 5.0-MW offshore turbine

A progression from the G10X 4.5-MW turbine, Gamesa is developing the G11X designed for variable and often extreme marine conditions, inclement weather, and challenging accessibility. A multi-variable control system minimizes blade vibration and reduces blade loads up to 30%. A permanent magnet generator and full converter comply with demanding grid code and connection requirements. Because of it’s modular design, the system keeps running even if any of the individual modules fail. A two-stage planetary integrated gear box with dual bearing design improves reliability by using fewer parts and avoiding the use of high speed bearings. The blades feature an airfoil design and the nacelle is designed to be spacious for technicians and tools, helping to reduce overall maintenance times and ensure safety. Gamesa has partnered with American shipbuilder Northrop Grumman to launch a prototype in the U.S. The two companies plan to install two of the turbines by 2012. Other features include:

-rotor diameter of 115 m

-3 upwind blades

-hub height adapted to site requirement (75-100 m)

4-MW offshore turbine

After six years of working on the Irish Arklow offshore wind farm, General Electric felt it had gathered enough experience to develop a new model. The company’s 4-MW offshore wind turbine is built around a permanent magnet generator, delivering high efficiency at low wind speed. Two main bearings transfer axial and bending loads from the rotor to the bedplate, increasing reliability. Built around direct-drive technology, the 4-MW turbine removes one of the most costly failures in offshore turbines, gearboxes, and replaces it with slow speed components designed for the offshore environment.

The turbine has a full power converter, as well as continuous close wind tracking, no yaw breaks, and no hydraulics. The rotor has a 110-m dia., and with a spacious nacelle and internal hub access, the turbine offers safety and maintenance advantages.

General Electric

www.ge.com

GE introduces 2.75 MW wind turbines

A North American manufacturer of wind turbines is introducing its newest members, a family of 2.5-MW wind turbines and more. All of the new models are will have higher annual energy productions (AEP) over the existing 2.5-MW wind turbine. The new machines include:

* GE’s 2.75-100, an uprate of the existing 2.5-100 wind turbine without mechanical component changes and only minor changes to the electrical system. GE’s 2.75-100 machine provides greater AEP in IEC TC II1 environments.

* GE’s 2.75-103, a combination of the 2.75 uprate and the 103-m rotor which uses GE’s 50.2 m proprietary blade design to offers the latest enhancements in aerodynamics, reduced acoustics, and robust performance. The new 2.75-103 wind turbine is optimized for IEC TC III.

GE’s 2.5-MW series, globally available, are in use at two largest projects: CEZ Romania’s Fantanele and Cogealac wind farms, which make up Europe’s largest onshore project, and at Caithness Energy’s Sheperds Flats wind project under construction in Oregon—the largest wind farm ever built in the United States.

These latest additions to the wind-turbine fleet expand GE’s ability to cover a broader range of wind conditions, yield the highest annual energy production in their class, and build upon the success of GE’s 1.5-megawatt machine, the world’s most widely deployed wind turbine with 14,000 units now installed.

GE Wind

gepower.com

Turbines save $3M in diesel for Alaska’s Kodiak Island

Wind turbines are helping the city of Kodiak — on Kodiak Island off the southern coast of Alaska — reduce its use of diesel fuel, lower its energy costs, and create cleaner energy. The Kodiak Electric Association (KEA), the island’s electric utility, installed three General Electric 1.5-MW turbines in 2009 as a part of the Pillar Mountain Wind Project.

After a year of successful operation, the KEA says the turbines have helped avoid using 930,000 gallons of diesel fuel. At about $3.50 a gallon, that’s more than $3,000,000. The turbines for the project have a total capacity of 4.5 MW, about 25% of the utility’s peak load demands. In addition, the wind turbines have supplied about 9% of annual system generation for the island.

“The use of wind turbines is saving our customers money and reducing emissions by directly displacing much of our diesel generation,” says Darron Scott, president & CEO of KEA. “The Pillar Mountain Wind Project is a significant step toward our target to generate 95% of our power from renewable resources by 2020.”

Most of the island is wilderness with only about 15,000 residents on the eastern side. The power grid is isolated with no external connections to other power sources. Prior to the installation of the wind turbines, a two-unit hydroelectric plant and seven diesel generators provided all of the island’s power.

The turbines feature controls and electronics, which help the machines meet grid codes and stay online even during severe disturbances. Because of the large percentage of wind generation on the KEA grid, studies are underway to examine high levels of wind penetration on smaller grids.

In addition to supplying the turbines, GE also signed a two-year service agreement with KEA. Under the agreement, GE will perform routine maintenance of the turbines for two years and provide maintenance training for KEA crews.

General Electric

www.ge.com

Wind turbine blade comes to DC with signatures and a message

GE Energy and the American Wind Energy Association (AWEA) recently delivered a petition from Americans in the form of a 131-foot wind turbine blade. The blade traveled more than 4,000 miles through 10 states gathering signatures from Americans who support a clean energy future. After it arrived in Washington, D.C., it was parked in front of the main gate at Nationals Park for the 2010 Congressional Baseball Game.

“The wind turbine blade, manufactured in South Dakota, symbolizes how clean energy creates new U.S. manufacturing jobs in addition to providing clean power for America’s homes and factories,” said Vic Abate, vice president for renewables at GE Energy. “It’s clear from the more than 6,000 signatures on this traveling petition that Americans are calling on the president and Congress to act on clean-energy policies that will increase energy security, reduce dependence on foreign oil and build a more sustainable clean energy future.”

More than 6,000 Americans across the country—factory workers, managers, engineers, service and transportation workers, public officials and the general public—signed the blade, with the printed message: “I’m helping to build America’s energy future,” issuing a call to Congress: Create more American jobs by enacting clean energy policies this year.

Facts about the wind turbine blade:

• The blade of a 1.5-MW wind turbine is nearly half a football field in length.
• Including the blade, the height of a 1.5-MW wind turbine is more than 75 feet taller than the Statue of Liberty.
• One 1.5-MW wind turbine produces enough energy to power about 400 households.
• To generate the same amount of electricity as a single 1.5-MW wind turbine operating for 20 years would require burning 43,500 tons of coal or 138,000 barrels of oil, and 90 million gallons of fresh water per year.

Sign the blade: GE sends wind blade on tour

GE recently kicked off a 28-day multi-state wind blade tour to emphasize the role renewable energy will have on America’s clean energy future. The tour will showcase one of GE’s 131-foot advanced technology wind turbine blades that will serve as a traveling petition signed by the public. The blade will cover 2,436 miles and travel through nine states during the tour.

As the country focuses on energy independence and moves to cleaner, smarter and more efficient energy production, GE believes the right government policies are key. Policy can help accelerate the creation of manufacturing jobs, increase investments and technological innovations that will lead to a more prosperous and competitive economy.

“Alternative energy solutions matter,” said Vic Abate, vice president of GE’s Renewable Energy business. “America has the power to choose a better energy future. American technology and innovation can create a cleaner, smarter, more efficient energy economy that will create more growth, more exports and more American jobs, but we need the right policy at the Federal level.”

The tour began in Aberdeen, S.D. and will wrap up in Dallas, Texas, in May as part of the American Wind Energy Association’s WINDPOWER 2010, the world’s largest wind energy trade show. In addition to Aberdeen, the blade will make planned stops in:

April 28: Trinity Structural Towers – Newton, Iowa

April 30: Top Crop Wind Farm - Ransom, Ill.

May 6:   Center of Science and Industry Museum - Columbus, Ohio

May 7:   Clean Air Fair – Columbus, Ohio

May 13: GE Appliance Park – Louisville, Ky.

May 15: Louisville Zoo – Louisville, Ky.

May 19: Molded Fiber Glass Companies – Gainesville, Texas

May 23: WINDPOWER 2010 - Dallas, Texas

Individuals who see the blade at the planned stops will have the opportunity to sign their name on it as a pledge of support for a clean energy future and urge America’s leaders to support innovative wind policies. The wind blade will carry the message “I’m helping to build America’s energy future” to highlight the personal role all Americans can play in making this clean energy vision a reality.

“The rest of the world is not standing still,” says GE’s Abate. “China and Europe have already enacted robust, clean-energy policies that are driving technology investments and creating real jobs. Sustainable policy works.”

The U.S. states with the most wind capacity installed are Texas, Iowa, California, Washington and Minnesota. All of these states have enacted state level renewable portfolio standards. Wind energy provides about 2% of the country’s electricity. Last year, the U.S. wind industry supported a total of 85,000 jobs in all 50 states.

GE believes Americans have the power to influence how government leaders view renewable energy. By signing the blade, says GE, people will send an unmistakable signal to policy leaders that they want renewable energy to play a more important role in their lives.

Control software gives turbines a power boost

A wind-energy producer says it has selected control software that will boost the output from its fleet of about 800, 1.5 MW wind turbines. NexEra Energy Resources, Juno Beach, Fla., says control software called WindBoost from GE makes it possible to increase output of GE 1.5sle wind turbines by up to 100 kW, thereby boosting output from 1.5 to 1.6 MW. Depending on wind speed and other site atmospheric conditions, the WindBoost control activates to increase the energy produced by each unit. The control software can be remotely turned on and off, providing flexibility to ramp up power production.

The software lets a wind turbine improve operation within the full IEC Type IIB design envelope. This expanded operating mode is expected to produce up to 4% more annual energy output per wind turbine. WindBoost is also said to provide “grid-friendly” features that balance increased output with grid integration requirements of a wind farm.

“Upgrading the turbines in our U.S. fleet gives us the opportunity for increased output without significant hardware additions,” said NextEra Energy Resources VP of wind operations Manny Sanchez.

Speed increasers for wind turbines

Wind-turbine gearboxes from GE Drivetrains, Erie, Pa., span four designs that handle 1.4 to 2.9 MW. On the low end, for instance, the CP 1.8 is a one stage compound planetary with one stage parallel shaft. The high end uses a two planetary (2P) gear trains. Middle two units handle from 1.8 to 2.3 MW and 2.0 to 2.7MW.

The company says these designs are the product of 40 years of planetary gear experience in the company’s mining business, 70 years of helical gear experience in its marine business, advances in metallurgy from its aircraft engines business. In addition, developments in structural vibration, acoustics, and special materials come from the company’s Global Research Laboratories.

The company says its wind-turbine gearboxes are working reliably in over 1,000 installations in just North America. Design and development emphasizes quality from the start, when defects are easily corrected without impacting turbine availability. It is accomplished, says GE, with a Design for Six Sigma process that produces robust designs subjected to extensive validation testing at the component, subsystem, and system levels in company test labs. The table gives of a few specs for the low and high end units.