GE: a busy bee with turbines and towers

Looks like GE’s been busy lately, though for one of the world’s largest companies that in itself is nothing new.

What is: For one, the turbine manufacturer recently installed its 15,000th 1.5-MW model at Basin Electric Power Coop.’s Crow Lake wind farm in South Dakota. The turbine is one of 108 GE units commissioned at the site, and will be owned and operated by Mitchell Technical Institute (MTI),  providing a learning opportunity for students in MTI’s Wind Turbine Technology Program.

MTI was able to fund the project through a grant from the U.S. Economic Development Administration, as well as funding from the South Dakota Governor’s Office of Economic Development, Basin Electric Power Cooperative, General Electric and MTI. Construction at Crow Lake began in October of 2010. GE says the project spans three counties in South Dakota and is the largest wind project in the United States owned solely by a cooperative, with a capacity of 151.5 MW.

In other news, GE has also acquired technology from Wind Tower Systems that will allow taller towers, while lowering installation and transport costs.  The need for taller, cost-efficient towers is becoming an important factor in the wind industry as blade lengths increase. WTS has been working on the development of a space frame tower system for use at wind farm sites that require hub heights of 100 m or more. The manufacturer says the tower will handle static and dynamic loads generated by the turbines.

WTS also has focused on ways to transport and install these taller towers. They will use standard flatbed trucks and a hi Jack system to eliminate the need for heavy-lift cranes. These developments help cost effectively extend the tower height, which in turn enables the turbine to produce more energy. As Victor Abate, vice president of renewable energy for GE Power & Wind, explains, “Taller towers are an important complement to longer blades. Longer blades capture more energy and in turn improve return on investment for wind farm developers.” Plans are underway to install a prototype of the GE’s space frame tower system to test later this year, with commercial availability targeted for 2012

GE www.ge.com

How loud is a wind turbine?

Because wind turbines are such a great source of clean, renewable energy, they’re usually greeted with a great deal of enthusiasm. But some complaints have been made that they can cause too much noise for residents living within a mile of the blades.

So just how noisy are these turbines?

The closest that a wind turbine is typically placed to a home is 300 m or more. At that distance, a turbine will have a sound pressure level of 43 decibels. To put that in context, the average air conditioner can reach 50 decibels of noise, and most refrigerators run at around 40 decibels.

At 500 m (0.3 mi) away, that sound pressure level drops to 38 decibels. In most places, according to Keith Longtin of GE Global Research, background noise ranges from 40 to 45 decibels, meaning that a turbine’s noise would be lost amongst it. For the stillest, most rural areas, Longtin says the background noise is 30 decibels. At that level, a turbine located about a mile away wouldn’t be heard.

GE www.gereports.com

88-MW Wintering Hills Project: Alberta, Canada

The Wintering Hills project in Alberta is part of a new “crop” of wind farms being built across Canada. At peak operation, the wind farm is expected to generate enough clean electricity to power approximately 35,000 Canadian homes. The 88-MW project is located near Drumheller, approximately 125 km (78 miles) northeast of Calgary.

Suncor Energy, joint owner with Teck Resources, has ordered 55, 1.6-MW turbines from GE, which will be delivered in the second quarter of 2011. The turbine makes use of a range of product features—including 82.5-m blades—to maximize power output while providing control flexibility and increased reliability with decreased maintenance requirements. The technology builds on GE’s 1.5-MW turbine.

“Alberta is rich in many resources that can be used to produce electricity, including wind energy,” said Keith Triginer, GE Energy’s newly appointed country executive for Canada. “We are working hand-in-hand with Suncor and others to make wind and other alternative energy sources a larger, more integral part of the Province’s overall energy supply.”

Construction on the project began in July 2010 and is expected to be complete by the end of 2011.

GE www.gepower.com

Suncor Energy www.suncor.com

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

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

General Electric recieves $1.4 billion wind turbine contract

GE announced earlier this month that it received a $1.4 billion contract from independent power producer Caithness Energy to supply wind turbines and provide services for an 845-megawatt (MW) wind farm project to be located in Oregon. The wind farm, called Shepherds Flat, has received the majority of the necessary government permits to operate and is ready to be built. When completed it will be larger than any wind farm currently in operation around the globe and will be powered by 338 of GE’s 2.5 MW wind turbines.

“This project underscores our commitment to harness the power of wind to meet present and future energy needs while reducing greenhouse emissions. The Shepherds Flat project will add more renewable energy to the west coast’s energy mix and help the region meet its demand for clean energy,” said Les Gelber, a partner at Caithness Energy.

“GE wind turbines have a strong track record of performance that has been proven in nearly every form of climate worldwide. Their ability to continually advance wind turbine technology will help us to provide our customer, Southern California Edison, with the reliability they expect,” added Gelber.

“The Caithness project highlights our ability to deliver integrated solutions in the clean energy space and it supports our overarching focus to provide first in class technology to our customers,” said Steve Bolze, president and CEO of GE Power & Water.

The Shepherds Flat wind farm is the first in North America to deploy GE’s 2.5xl wind turbine, which has been proven in Europe and Asia.

“The 2.5-MW wind turbine is the latest evolution of GE’s wind turbine technology and provides customers with greater efficiency, reliability and grid connection capabilities. The 2.5-MW builds upon the success of GE’s 1.5-MW wind turbine, the world’s most widely deployed wind turbine with more than 12,000 installed,” said Bolze.

Caithness Energy estimates that the $2 billion project will inject $16 million annually of direct economic benefits into Oregon, and will employ 400 workers during construction and 35 during operation. Construction will be on a large scale not only because of the large number of turbines, but because 85 miles of road and 90 miles of power connection to the grid will be built. Construction is scheduled to begin in 2010 and be completed in 2012.

The 2.5xl wind turbines for the Shepherds Flat wind farm will be assembled at GE’s site in Pensacola, Florida. In addition to supplying the wind turbines, GE will provide ten years of operational and maintenance services to the project. GE Energy Financial Services, which holds a large portfolio in more than 40 wind farms with a total capacity of 6 GW is also investing in the Shepherds Flat project.

In addition to supplying the wind turbines, GE will provide ten years of operational and maintenance services to the project.

“As the nation’s leading utility for renewable energy, we are enthusiastic about the size and quality of this project,” said Marc Ulrich, Southern California Edison Vice President, Renewable and Alternative Power. “Wind power is an essential component to creating a clean, green energy future for California and the rest of the nation.”

The project will help California meet both its capacity needs and renewable energy goals. With the capability to generate two billion kilowatt-hours per year of renewable energy, the wind farm will represent one of the largest projects in Southern California Edison’s renewable portfolio. The project will provide enough clean energy to power approximately 235,000 average California households – according to US Environmental Protection Agency methodology – and will avoid more than 1.5 million tons a year in greenhouse gas emissions, compared to equivalent fossil fuel generation.