By Teresa Hansen, Senior Editor
Energy supply was often front page news during 2007. The growing demand for electricity, increasingly volatile fuel prices, growing concerns about the environment and global warning and talk of carbon caps have created a business environment that can be hard for power generators to navigate. Whether generators are using fossil fuel, uranium or renewable resources to create electricity, the best strategy isn’t always clear. Customers; shareholders; local, state and federal officials; special interest groups and regulators all figure into the mix when companies plan to build or upgrade a power plant. This year’s Projects of the Year Award finalists found a way to successfully navigate these challenges and complete projects worthy of recognition.
On December 10, 2007, at the Sheraton Hotel in New Orleans, Power Engineering magazine recognized the 2007 Projects of the Year Award finalists and announced the winners. Each year the magazine’s editors recognize some of the world’s best power projects from four major categories: gas-fired, coal-fired, nuclear and renewable. The editors this year chose one winner and one honorable mention recipient in each category.
Best Gas-fired Projects
Turkey Point Power Plant Expansion Project
Despite being blasted with continuous heavy rains, having to contend with two major hurricanes that swept Florida’s southern region and working in a highly-sensitive environmental area, Florida Power and Light (FPL), Zachry and Black & Veatch completed the 1,150 MW Turkey Point Power Plant Expansion project on-time and under budget. The 2007 Best Gas-fired Project of the Year was completed in March 2007 after nearly three years of work.
The addition and expansion at the Turkey Point Power Plant, Homestead, Fla., is an 1,150 MW, 4-on-1 combined cycle facility that uses GE-7FA technology and is the 2007 Best Gas-fired Project.
The addition and expansion at the Turkey Point Power Plant, Homestead, Fla., is a 4-on-1 combined cycle facility that uses GE-7FA technology. The facility contains four combustion turbine generators, four Nooter heat recovery steam generators (HRSGs) and one steam turbine generator. Construction value was estimated at $120 million. Total project value was approximately $200 million.
The new gas-fired plant is a step in FPL’s continuing efforts to attain and maintain a diversified fuel mix and reduce its reliance on oil-fired generation. The plant contains next-generation environmentally friendly equipment designed to meet all health-based air emission permit requirements. Recent control technology improvements also reduced emissions.
FPL chose to build the new 1,150 MW power plant at its existing Turkey Point Power Station site to take advantage of already existing infrastructure. The expansion was built in an area of coastal mangrove wetlands, which is home to more than 60 species of birds and animals and an optimal habitat for the endangered American Crocodile. Zachry and FPL worked closely with federal, state and local agencies on the project’s design to ensure minimal environmental impact.
The challenges presented by the sensitive environment weren’t the only obstacles the FPL-Zachry team faced during construction. Heavy rains and two major hurricanesHurricane Katrina (175 mph, Aug. 23, 2005), and Hurricane Rita (175 mph winds, Sept. 17, 2005)impacted the schedule, caused reoccurring damage to the new construction and dampened employee morale.
Following the storms, Zachry employees worked weekends and overtime to help mitigate the delays they created and the 1.3 million labor workhour project was completed on time and within budget.
Port Westward Power Plant
Port Westward Generating Plant, a natural gas-fired, combined cycle plant is the newest member of Portland General Electric’s (PGE’s) family of power generation resources and the 2007 Best Gas-fired Project Honorable Mention. It is the first plant brought online by PGE in more than 10 years and also one of the first baseload combustion turbine plants built in the United States since 2001. The 400 MW gas-fired plant is the first Mitsubishi “G1” plant in operation worldwide and one of America’s most efficient combined cycle power plants.
Port Westward began commercial operation in June 2007 and is located near PGE’s existing 545 MW natural gas-fired Beaver Power Plant, which was built in 1974. The site takes advantage of existing electrical transmission and gas transportation infrastructure. A transmission line was constructed from the Port Westward site to PGE’s decommissioned Trojan Nuclear Plant site, which allows power to be delivered directly into PGE’s grid.
Mitsubishi Power Systems provided the power island equipment which includes one steam cooled M501G1 gas turbine, one steam turbine, and a Deltak triple-pressure HRSG, with best available technology to limit emissions of NOX to 2.5 ppm and CO to 4.9 ppm, well below department of environmental quality permitted requirements.
PGE negotiated its own turbine deal with Mitsubishi, but it did not want to lose the benefits that come with a full-wrap turnkey engineering-procurement-construction (EPC) agreement simply because it negotiated its own turbine/power island deal with the OEM. Therefore, it assigned the turbine/power island contract to the EPC, Black & Veatch Construction Inc.
Like the Turkey Point project, Port Westward also was permitted and built in a sensitive environmental area which had to address wetlands, archeologically significant areas and endangered species.
Now that the plant is operating, heat rate and capacity both are exceeding contractual guarantees. Heat rate is below 6,700 Btu/kWhr and output is significantly higher. The plant has been dispatched daily since it began commercial operations. It cycles well in the 50 percent to 100 percent load range and has high ramp rates. A lower heat rate combined with cycling capabilities provides PGE’s trading floor with good plant dispatching options. By reducing its dependence on wholesale market purchases, Port Westward is helping PGE meet its commitment to provide reliable power at stable prices.
Best Coal-fired Projects
Walter Scott, Jr. Energy Center Unit 4
In February 2002, MidAmerican Energy Co. became one of the United States’ earliest adopters of supercritical coal-fired technology when it decided to build a supercritical cycle (3803/1057/1103) 790 MW power plant in Council Bluffs, Iowa. Walter Scott, Jr. Energy Center Unit 4 is the 2007 Best Coal-fired Project of the Year.
MidAmerican Energy Co.’s supercritical cycle (3803/1057/1103) 790 MW power plant, Walter Scott, Jr. Energy Center Unit 4, is the 2007 Best Coal-fired Project of the Year.
MidAmerican Energy Co. selected Mitsui and Company Energy Development as the EPC after competitively bidding a turnkey EPC scope in 2002. Mitsui assembled an international EPC team lead by Hitachi America Ltd. Hitachi was responsible for the entire EPC scope and the technology derived from a large network of similar operating units in Japan. Sargent & Lundy joined Hitachi’s team as a subcontractor with the responsibility of overall plant design, detailed engineering and balance-of-plant (BOP) equipment procurement support. Hitachi America Ltd. competitively bid the construction scope in three packages (civil, boiler erection and BOP installation) and selected Aker Kvaerner Songer Inc. (AKSI) to supply all three scopes.
Walter Scott, Jr. Energy Center is on the Missouri River opposite Omaha, Neb. At the heart of Unit 4 is a Benson, sliding pressure steam generator with a design that includes a spiral wound furnace and a double back pass convection section. It is the first of its kind to be built in the United States. The steam turbine generator, manufactured by Hitachi, is a tandem compound, four-flow, single shaft, 3,600 rpm machine. The plant incorporates the latest pollution controls for NOX, SO2, mercury and particulate matter regulation and is the first plant in the United States to have a mercury limit (.0000017 lb/mmBtu) specifically noted in the air permit.
The new unit consists of a Hitachi 1050 F/1100 F tandem-compound, four-flow turbine with 40-inch last-stage titanium blades, operating at 3,675 psig. The 870 MW steam turbine is the largest Hitachi turbine installation outside of Japan. The boiler is a pulverized-coal-fired, supercritical steam generator designed for 5.5 million lbs/hour maximum continuous rating.
Hitachi based the plant design on a 1,050 MW unit that it supplied for the Tokyo Electric Power Co. at its Hitachi Naka plant near Hitachi City. This “standard” approach expedited the overall process, allowing the major equipment to be manufactured to support an aggressive project schedulein this case, 45 months.
Critical path procurement included mill orders placed with Sumitomo Metals for alloy boiler components and rotor forgings with Japan Steel Works in October 2003 and boiler structural steel with CTIW in November 2003. Construction work began in 2003 with initial site preparation. The plant was completed in June 2007.
The MidAmerican Energy Co. project team fostered excellent state and local community relations, as well as strong labor relations with the local building trades. Using more than 2,000 skilled laborers, it was the largest construction project ever undertaken in Iowa, as well as the largest generation project globally for MidAmerican Energy.
In addition to construction activities, the EPC team provided training to plant operators and maintenance staff. The EPC team created a formal operator training program to address unit design, the unique characteristics of the supercritical boiler and the introduction of Japanese technology.
Allen S. King Plant Rehabilitation Project
The Allen S. King Plant Rehabilitation Project was successfully completed and dedicated July 25, 2007 and is the 2007 Best Coal-fired Project Honorable Mention award winner. The project scope encompassed installation of state-of-the-art emissions control equipment and rehabilitation of the existing electric generation equipment to return this Xcel Energy plant to its original design capacity while significantly reducing the plant’s airborne emissions. The King Plant, located in Bayport, Minn., (approximately 20 miles east of the Twin Cities) is a 600 MW cyclone-fired boiler originally placed in service in 1968.
The King Plant Rehabilitation Project is the first product of a unique voluntary program by Xcel Energy to reduce emissions while providing cost effective and reliable base load power generation for all of its customers. In 2001, Minnesota’s then Governor Ventura signed into law an amendment entitled “Emissions Reduction Rider.” This Rider allows any public utility in Minnesota to seek expedited and/or enhanced cost recovery for qualifying voluntary emissions reduction projects. For a project to qualify under the Rider, the project must, among other things, reduce plant emissions to levels below those currently permitted at the specific plant.
The Allen S. King Plant permitting and equipment design activities began in 2003, with on-site construction activities beginning in 2004. It was the first of three Xcel Energy projects tied to the Emissions Reduction Rider to be completed.
The scope of the project included installation of a complete air quality control system (AQCS) that included selective catalytic reduction (SCR) for NOX control, flue gas scrubbers (spray dryers) for control of SOX emissions and fabric filters for control of particulate matter. It also included complete steam turbine replacement; steam generator rehabilitation, including replacement of the cyclones and lower furnace; conversion to balanced draft operation; circulating water system modifications, including new cooling towers; coal handling upgrades; auxiliary electric system upgrades; complete distributed control system replacement; and other equipment rehabilitation to extend the plant’s life.
As an adjunct to the Emissions Reduction Rider law, Xcel Energy agreed to study reducing airborne emissions from its coal burning plants in the Twin Cities metropolitan area and propose additional emissions reduction projects which would also qualify under the Rider.
Xcel Energy managed a team of employees, engineers, equipment suppliers and construction companies on an extremely space limited site while maintaining plant operations. Challenges included a limited set of original plant drawings; minimal site lay down area, labor shortages, severe winter weather and an industry that continued to boom.
The team installed the AQCS, including the SCR, FGD system, fabric filters, ID fans and supporting equipment while the plant remained in operation. During a nine-month outage, the team completed the boiler, turbine, coal yard and controls work. The retrofitted plant’s start-up was also challenging because new and old components and systems were brought on-line using a completely new controls system.
This rehabilitation project reduced SOX emissios by 91 percent; NOX emissions by 89 percent; particulates by 20 percent and mercury by approximately 20 percent. This environmental improvement, coupled with the commitment to reliable base load production, has balanced Xcel Energy’s responsibilities to the environment, its customers and its shareholders.
Best Nuclear Projects
South Texas Project
The South Texas Project (STP) nuclear power plant substantially increased equipment reliability, generation and revenue by replacing all its low pressure turbines between October 2006 and April 2007. The cost recovery period for the nearly $100 million project, this year’s Best Nuclear Project, has been projected at less than 18 months. This $100 million project increased the output of each STP unit by 70 MW, raising the electricity delivered to the grid from 1,280 MW to 1,350 MW per unit.
The project stemmed from an STP management review in early 2003 of turbine-related equipment issues, unplanned outages, revenue losses and unbudgeted costs for replacement electricity.
Planning the six huge components’ manufacturing and replacement spanned several years as well as the globe. Manufacturing the new turbines, supplied by Siemens AG, had a two-year lead-time and required worldwide coordination. Design activities were based at a Siemens facility in Florida but relied on engineering work done in India and Germany. Initial fabrication of each turbine’s 55-ton upper cylinder and 85-ton lower cylinder was performed in Indonesia. Forgings were made in Italy, Germany, Poland, England and other countries throughout Europe as well as at a Siemens plant in Charlotte, N.C.
The final production stages were directed and performed at Siemens’ European center for steam turbine work, located in Mulheim, Germany. Personnel in the facility and subcontractors across Europe machined the equipment, which was then assembled and tested in the Mulheim plant.
As Siemens completed and successfully tested the turbines, each was moved down the Rhine River to Rotterdam, then transferred to a merchant vessel and shipped to Houston. There, each turbine was loaded onto a special transport vehicle and routed on circuitous delivery route to avoid obstacles. Although Houston and STP are just 90 miles apart, it took three days per turbine to cover the roundabout course.
The turbines for Unit 1 were delivered in the summer of 2006 and installed during the unit’s refueling outage that fall. Despite some challenges, the work was completed in a world-record time of 26 days and 11 hours.
Complications arose when the Unit 2 turbines were installed during that unit’s refueling outage in April 2007. When the old turbines were removed, the installation team had to cut and fit the spaces and connections for the new turbines more than expected, due to inaccurate or inadequate detail in plant construction records. Modifications were made on the spot, which added 2,800 labor-hours and $200,000 in costs. Further, poor weather slowed work on the rooftop turbine train.
In addition, the main generator rotor was replaced in the Unit 2 outage. The turbines and rotor were replaced in 28 days, setting another world record for the replacement of four turbine train components.
The units’ increased outputs were realized without any design changes or modifications in the plant’s primary side (reactor, steam generators and so on). The increased generation resulted from the more efficient use of existing steam.
The total installation time for both units was 54.5 days and the final cost was $95.2 million. In June 2007, the price of a megawatt-hour of electricity in Texas ranged from $45 to $75 for off-peak and peak periods, respectively. Using the mid-point in that range as the average price, the additional production should increase the plant’s revenue $36.79 million annually per unit. Given the current average price, the production gain from the new turbines will offset the entire project cost within 18 months.
Comanche Peak Steam Generator Replacement
Luminant (formerly TXU Generation Co.) and Bechtel Power Corp. completed a modernization project in April 2007 that broke the record for the fastest replacement of aging components at a nuclear power plant. The Best Nuclear Project Honorable Mention award winner, a steam generator and reactor vessel head replacement project at Comanche Peak Unit 1, was completed in 55 dayseight days less than the previous record for a steam generator replacement-only outage.
Comanche Peak is located about 60 miles southwest of Dallas and is home to two 1,150 MW Westinghouse pressurized water reactor (PWR) units. Luminant decided to replace the components to improve plant reliability and ensure continued safe operation.
The project’s scope included reactor vessel head replacement, along with new cabling, new cable trays and a new air handling unit with all new ductwork. The new steam generators’ upgraded design required installation of rerouted main feed water piping, along with new seismically designed hangers, snubbers and whip restraints. The rerouted feed water piping interfered with existing containment building ventilation ductwork, so the ductwork also required rerouting and new hangers. The new steam generators’ instrument tap locations required installing new instrument tubing, as well as new hangers.
The steam generators were built in Spain and shipped to Houston where they then traveled to Comanche Peak via a specially equipped train. The new reactor vessel head, also fabricated in Spain, was outfitted with new control rod drives in Pennsylvania and transported by barge to Houston, then trucked to the site.
As with most steam generator replacements, Bechtel had to cut through the containment building wall to create an opening large enough to remove the old steam generators and move in the new ones. Hydrodemolition was used to remove the concrete for the opening in the containment building. Tanker trucks brought in about 1.5 million gallons of water, which was delivered to robots on a work platform through high-pressure hoses using 12 diesel powered pumps.
The existing crane in the containment building did not have adequate lifting capacity to lift either the old or new steam generators; therefore, Bechtel had to construct an alternate lifting system inside the building. Bechtel also constructed an outside lift system, the tallest ever used for replacing steam generators.
The project team used laser templating to create three-dimensional models for installing the new steam generators and connecting them to existing coolant piping. After installation, each pipe weld’s integrity was verified with computed radiographic testing (RT); 52 of 63 (83 percent) feed water and auxiliary feed water welds passed RT at the first inspection and all 21 large-bore piping welds passed the first time.
As with some of this year’s other award winning projects, Mother Nature presented the biggest problem during the project. On the outage’s first day, north-central Texas experienced its worst dust storm in more than 20 years. The work platform and the hydrodemolition robots were the only equipment qualified to operate on the first day.
Project staffing was another project challenge. More than 1,300 workers, including 900 craft workers, were needed to complete the project. Luminant and Bechtel relied heavily on subcontractors to perform work traditionally performed by direct-hire personnel.
Comanche Peak Unit 1 is an important electricity source for Texas, generating nearly 10.3 million MW hours of electricity in 2006. This equipment replacement will allow it to continue as a reliable source of electricity and will reduce the plant’s maintenance costs. In addition, the new equipment positions Comanche Peak Unit 1 for a power uprate, which will allow it to provide additional megawatts to the grid. Comanche Peak submitted its uprate application to the Nuclear Regulatory Commission (NRC) late last year, but has not yet received approval. The power uprate must be reviewed and approved by regulators, including the NRC.
Best Renewables Projects
Wind farms are normally associated with mountainous areas and remote regions. But the 2007 Best Renewables Project of the Year Award winner is a wind farm that is planted in a city on the site of an old steel mill. The Steel Winds Wind Farm, co-owned by BQ Energy and UPC Wind, is on a 30-acre portion of the old Bethlehem Steel mill, located along the shores of Lake Erie in Lackawanna, N.Y.
The 20 MW wind farm, consisting of eight turbines, marks many firsts. It is the first urban wind farm in the country, the first to go up on a former industrial site, the first wind farm on the American Great Lakes and the first commercial deployment of Clipper Windpower’s 2.5 MW Liberty series wind turbines.
These turbines feature several innovative features, including a compact two-stage helical designed to reduce loads, minimize the likelihood of damage and increase gearbox lifespan. The turbines use multiple generators and a multiple path distributed gearbox. These generators split the load by a factor of 16. If one generator goes off line, the other three continue. The Liberty is one of the largest land-based wind turbines in the world and is the largest wind turbine manufactured in North America.
Steel Winds returned the Bethlehem Steel facility to productive use under the New York Department of Environmental Conservation Brownfield Cleanup Program. While permitting was perhaps easier at this site than at the typical hilltop or ridgeline location, it was far from easy. The community had no experience with wind farms and much discussion ensued to calm fears about possible noise and environmental factors.
BQ Energy paved the way for the project by finding the site, arranging the brownfield grants, negotiating the lease and accelerating the permitting. UPC Wind was included as co-developer to contribute its wind farm construction expertise.
Because the brownfield site was so tight, the developers wanted the biggest turbine with the highest yield. To produce 20 MW, it was easier to place eight 2.5 MW machines rather than 12 or 13 smaller turbines.
Once construction began, rigorous environmental protocols had to be followed with regard to any potential brownfield material. The construction period stretched from October through March, mainly due to the high winter winds from Lake Erie, which complicated turbine erection. In addition, UPC learned some valuable lessons specific to the Clipper machines. These turbines have four major parts that are assembled on sitethe baseplate, gearing/genset and two parts for the roof assembly. Initially, assembly was attempted at hub height, requiring four picks from a crane and involving some fancy footwork 80 meters in the air during windy conditions. The construction crew realized that Liberty turbine assembly should be done on the ground so they would need only one crane pick to mount the turbine on the tower.
The project is being operated by UPC Wind and Clipper will provide turbine operation and maintenance services for the first five years.
The new wind farm has brought jobs to the area and helped revitalize a region that has suffered many decades of decay.
Burbo Bank Offshore Wind Farm
Offshore wind farms are a big part of Great Britain’s strategy for meeting its environmental regulations associated with electricity generation. Burbo Bank Offshore Wind Farm, the Best Renewables Project Honorable Mention award winner, can add up to 90 MW of clean, sustainable energy to the country’s electricity grid, helping it meet its environmental goals. Located roughly four and a half miles offshore in Liverpool Bay, the wind farm consists of 25 Siemens Power Generation wind turbines, each rated at 3.6 MW. DONG Energy, the facility’s Danish-based owner, expects the wind farm to produce 315 million kilowatt hours of electricity each year.
Erection of the Burbo Bank Wind Farm involved two firsts for Siemens Power Generation, the turbines’ manufacturer. For the first time following acquisition of the Danish wind energy company Bonus in 2004, Siemens erected a wind farm offshore. It also was the first time that Siemens’ highest rating, mature Type SWT-3.6-107 wind turbines have been used in an offshore project. Erecting the 25 wind turbines, each of which has a rotor diameter of 107 meters (52 meter blades and hubs) involved some unique challenges and approaches. These challenges didn’t keep the installation team from completing the project ahead of scheduleall 25 wind turbines were erected in 43 days. Construction of the entire project took about 14 months, commencing early in April 2006 and generating its first electricity in July 2007.
The nacelles, rotor hubs, rotor blades and towers for the 25 wind turbines were manufactured in Denmark and shipped from Aarhus to the Port of Mostyn in North Wales, where Siemens leased a site for the project’s onshore work. The installation team preassembled the 65- meter-high towers upright and then tested all internal and electrical systems before loading the turbines on the installation vessel.
Each turbine is anchored to the seabed by a foundation consisting of a steel monopile five meters in diameter and 52 meters long. The foundations are driven up to 25 meters into the seabed. Electric cables buried under the seabed connect the wind turbines to the land. Onshore, these cables cross almost two miles underground and connect to a substation that feeds the electricity into the national grid.
The wind farm’s production will depend on the actual wind speed. The turbines begin to generate at a wind speed of only 4 meters per second (m/s) and level out at 3.6 MW when the wind speed reaches 14 m/s. DONG Energy expects the average wind speed on site to be 9 m/s.
Technicians performing annual maintenance inspections will access the turbines by boat. For this reason, Siemens set up an operation and maintenance facility in Liverpool harbor, which will be used as a base for the routine monitoring, management and maintenance of the wind farm.
Each wind turbine is designed to run approximately 6,000 hours a year for 20 years, which according to DONG Energy will save 6.4 million tons of CO2, as well as significant amounts of other greenhouse gases.