By Sharryn Harvey, Online Editor
Each year at POWER-GEN International, the editors of Power Engineering magazine recognize the best projects of the year by honoring them at an awards dinner. The Projects of the Year awards recognize excellence across four major categories: gas-fired, coal-fired, nuclear and renewable power generation. This year the magazine’s editors chose one winner and two honorable mention recipients in each category.
Best Coal-fired Project
Dallman Unit 4, City Water, Light & Power, Springfield, Ill.
 Dallman Unit 4 was selected as the best coal-fired project of 2009 by editors of Power Engineering magazine. |
Dallman Unit 4 is one of the cleanest subcritical pulverized coal units in the U.S. The 200 MW plant is owned by Springfield, Ill., municipal electric utility, City Water, Light & Power, which negotiated a landmark agreement with the Sierra Club that allowed the Dallman Unit 4 project to proceed without any litigation over its air permit. This itself is a significant achievement in the current fossil-fired project development environment.
The agreement called for improvements to the air quality control systems, efficiency improvements at the existing Dallman units, increased efficiency programs for customers and the purchase of 120 MW of wind capacity.
The new unit construction project started in December 2006. With a $515 million price tag, it is the most expensive capital project ever undertaken by the city of Springfield.
Dallman Unit 4 uses a Foster Wheeler pulverized coal boiler and is 34 percent more efficient than existing units at the station. Its flue gas cleaning processes will remove 99 percent of the sulfur dioxide, 95 percent of the nitrogen oxide formed when burning high-sulfur Illinois coal and 90 percent of the mercury.
The plant uses a plume-abating cooling tower to prevent heated cooling water from being released into a nearby lake and significantly reduces the chance of fog developing near an adjacent highway.
The project team overcame obstacles including challenges with the prevention of significant deterioration (PSD) air permit, but CWLP collaborated with the Sierra Club to ensure a smooth progression through the permitting process. Tighter emission standards meant design changes, even though project engineering and procurement were more than 50 percent complete. Officials, however, decided to keep the project moving ahead.
The final result was a project completed seven months ahead of schedule and within budget. Because of its high efficiency, energy produced by Dallman 4 is expected to provide $12 million in savings in its first year of operation.
Honorable Mention
Spurlock Station Generating Unit 4, East Kentucky Power Cooperative, Maysville, Ky.
Spurlock Unit 4’s additional capacity was needed because the 16 members of the East Kentucky Power Cooperative were quickly growing. The $528 million project was designed to be one of the cleanest coal-fired plants in the U.S.
The unit’s circulating fluidized bed (CFB) process burns crushed coal up to 3/8” at temperatures ranging from 1,500 F to 1,650 F, a low furnace firing temperature that results in low NOX production. The CFB process removes about 98 percent of the sulfur dioxide and produces 20 percent of the NOX of conventional coal plants. Unit 4’s just-in-time limestone preparation system integrates the system into the boiler building and injects it directly from the mill into the boiler.
The unit also includes a 15 percent steam turbine bypass system that allows the boiler to start up independently from the steam turbine. This reduces turbine thermal stresses and unit startup time.
With CFB technology, Spurlock Unit 4 can burn a wide variety of coals. The unit is also designed to burn petroleum coke, biomass, shredded tires and renewable fuels such as switchgrass. Even with all its complexities, the CFB process results in the lowest production costs of all EKPC’s generating units. Construction was completed in 33 months and came in at the projected budget. No major problems were encountered during start-up, from first fire to commercial operation.
OPPD Nebraska City Unit 2, Omaha Public Power District, Omaha, Neb.
The Omaha Public Power District’s Nebraska City Unit 2 is the first baseload generating plant built by OPPD in more that three decades. The 682 MW unit was built at a capital cost of $950/kW and was completed on time and several million dollars under budget.
Unit 2 uses the latest emissions control equipment at an estimated project cost of $65 million. To achieve the highest emissions controls, the plant uses elevated main steam and reheat steam temperatures to capture half of the efficiency difference between subcritical and super-critical coal plant technology. Unit 2 reduces emissions by 70 percent over neighboring Unit 1.
Unit 2’s stack is one of its innovative features. It sits 300 feet below the 700-foot tower that rises above Unit 1, but still exceeds environmental requirements and provided construction cost savings.
OPPD will use about half the power generated by Unit 2 and sell the rest to seven other public power entities in the region.
Best Gas-fired Project:
Gateway Generating Station, Pacific Gas and Electric Co., Antioch, Calif.
 Pacific Gas & Electric’s Gateway Generating Station was selected as the best natural gas-fired project of 2009. |
PG&E’s 590 MW gas-fired Gateway Generating Station is a 2x1 combined cycle unit featuring two General Electric model PG7241FA combustion turbine generators and a single GE D11 tandem compound reheat double-flow steam turbine generator nominally rated at 240 MW.
Gateway began as Mirant’s Contra Costa Unit 8 combined cycle project. Work was suspended in 2002 at 10 percent completion and PG&E received rights to the project in 2006. The original plant was designed to use cooling water from the San Joaquin/Sacramento Delta. Due to the significant impacts to the Delta eco-system and in keeping with its environmental stewardship, PG&E decided to reconfigure the plant to dry cooling using a 36-cell air-cooled condenser. The reconfigured plant required significant design modifications and a revision of the air permit for the project to reflect plant changes.
Using dry cooling reduced water use by approximately 98 percent and none of the water is taken from the river. Waste water streams were decreased by 99 percent and the new plant yields less carbon dioxide for every megawatt-hour of power produced.
Gateway was the first plant constructed by PG&E in 20 years. The project was completed in January 2009, on time and under budget, with an exceptional safety record.
Honorable Mentions
Gissi Combined Cycle Power Plant, Abruzzoenergia S.p.A., Italy
Gissi is a new 800 MW gas-fired combined cycle plant in the Abruzzo region of central Italy. The project demonstrates an operating mode that allows plants to stay open at loads as low as 20 percent. Combined cycle plants in that region of Italy are usually shut down overnight since emission limits cannot be met at loads lower than 60 percent of gas turbine load.
Gissi has two 400 MW single-shaft power trains each one comprised of a GT26 gas turbine, a triple-pressure reheat, horizontal heat recovery steam generator, an STF15c steam turbine and a TOPGAS hydrogen-cooled turbogenerator. The steam-water cycle is a triple-pressure reheat cycle with the high pressure steam at 565 C and 140 bar at the inlet of the steam turbine.
Altering the water-steam cycle around the operation of the gas turbine and mirroring this in the control system allowed for a new low-load concept whereby the power plant could run from full load down to 30 percent load and stay within emission limits. In addition, when parking the plant around 20 percent combined load, emissions are about the same as at 100 percent. The gas turbine can reach baseload operation and the plant can achieve more than 95 percent of the combined cycle baseload output in less than 20 minutes. Because of reduced maintenance costs, every start-stop operation avoided will save about 15 equivalent operating hours.
Emporia Energy Center, Westar Energy, Emporia, Kan.
Westar Energy’s 665 MW natural gas-fired Emporia Energy Center now includes seven state-of-the-art combustion turbine generators that supply power to the grid during peak periods. The project was completed in two phases: The first in 2008 with an initial capacity of 340 MW, which included four GE LM6000 turbines and one GE 7FA combustion turbine, and the second phase which was completed in May 2009 with the installation of two additional GE 7FA combustion turbines. With the installation of four aero-derivative units, much of the plant has an extremely fast start-up time and can also provide support for Westar’s wind energy portfolio.
The plant was completed for $305 million, which was $13 million under budget and two months ahead of schedule. It also tested out at 55 more megawatts than planned and has a 12 percent lower cost per kilowatt than anticipated.
Best Nuclear Project
Diablo Canyon Power Plant Unit 1 Steam Generator Replacement, Pacific Gas & Electric Co., Avila Beach, Calif.
 The 2009 best nuclear project was PG&E’s Diablo Canyon Unit 1 steam generator replacement project. |
Pacific Gas and Electric’s Diablo Canyon Nuclear Power Plant’s Unit 1 steam generator replacement was completed during a planned refueling outage and took 58 days—the third-shortest duration of any steam generator replacement project in the country.
Four new steam generators were installed, each 70 feet long and weighing 350 tons. The project team used more than 11,000 lessons learned from the first steam generator replacement in 2008 in Unit 2 to complete this project, installing a total of eight generators. It was the largest project at Diablo Canyon since its completion in the mid-1980s.
Project planning began 45 months before the January 2009 outage. At the project’s peak, almost 1,200 SGT West employees worked on alternating 12-hour shifts around the clock. The entire team met or exceeded all environmental requirements and restored the site to as-is condition with negligible environmental impact. Employees had to deal with high radiation areas, confined spaces and working on multiple levels at the same time, among other challenges. They also worked with a replacement window that was reduced from 50 to 40 days during the outage and were still able to achieve a safety event reduction of 55 percent over the Unit 2 replacement and finished under the radiation dose goal.
Replacing the steam generators in both units ensures that Diablo Canyon will run through the rest of its license, which expires in 2025.
Honorable Mentions
SmartSignal at Waterford 3,Entergy Nuclear, Killona, La.
Entergy Nuclear installed SmartSignal at the Waterford 3 nuclear power plant in Louisiana as a pilot for the overall Entergy fleet. SmartSignal is a predictive monitoring tool that trends large amounts of plant process data to provide early detection of equipment degradation and prevent surprises, unplanned outages and excessive maintenance costs. All major rotating equipment is monitored, including feedwater, condensate, reactor coolant and the main turbine generator. Entergy Fossil has been using SmartSignal for more than five years with success.
Productivity and efficiency gains have been realized in the focus areas of equipment, processes and organization. Due to Waterford 3’s success, Entergy Nuclear is looking to expand SmartSignal to other plants in the southern part of the fleet in 2010 and to expand the use of the software to other equipment including transformers, the safety system and cooling towers.
River Bend Wireless, Entergy Nuclear, St. Francisville, La.
Entergy Nuclear’s River Bend Nuclear Station is next to the Mississippi River in Louisiana. For the water intake process, the Allen Bradley control equipment is located at the Makeup Water Structure, the Circulatory Water System and Clarifier building. Traditionally, the solution has been to use fiber-optic cables to tie all the systems together. To monitor and operate equipment at the Makeup Water Structure, staff had to travel several miles to the river. Two miles of cable and fiber optics needed replacing and, when the river level was high, monitoring required a boat, creating a safety hazard.
The Innovations Group at Entergy Nuclear devised a way to use wireless technology to replace the traditional cable, conduit and fiber optics and tie-in River Bend to the other three locations, making River Bend one of the first nuclear plants to implement wireless technology for the continuity of power project. With wireless, River Bend has reduced project costs from an initial $7 million projection to $3 million. It has also reduced the need for boats to monitor the cables, especially important during times of flooding on the Mississippi River.
Last fall, Entergy Nuclear planned to extend the wireless network to the plant’s Clarifier and to the Circulatory Water System in 2010.
Best Renewable Project
Sierra SunTower, eSolar, Lancaster, Calif.
 The year’s best renewable energy project, eSolar’s 5 MW Sierra Sun Tower, is a concentrating solar thermal power plant in Califormia. |
eSolar’s Sierra SunTower is a 5 MW concentrating solar thermal project that is one of the first of its kind in the United States and one of the only operating CSP towers in the U.S. It features 24,000 heliostats that form two modular fields composed of north- and south-facing mirror sub-fields that connect to a dual-port receiver atop a central tower. Within the receivers, water is converted to steam, which drives a reconditioned turbine generator. Steam is condensed back to water through cooling and the process repeats.
The company developed pre-fabricated heliostats and used a minimal amount of steel and concrete for the mountings, which made them cost-effective and reduced engineering and construction costs. Also, by constructing the project on pre-developed land, eSolar was able to avoid environmental harm. The project’s design allows the mirrors to be mounted directly on the ground without penetrating the desert floor, helping the site return to its natural state after decommissioning. The field layout uses a simple, linear design that eliminates the need for high-precision surveying and ground penetration.
The control system uses a sun-tracking system that calibrates heliostats and monitors the performance of each heliostat, resulting in pointing accuracy and high thermal concentration ratios.
e-Solar’s SunTower will provide research and data for future plants. Three power purchase agreements have already been signed for utility-scale projects ranging in size from 92 MW for El Paso Electric and 92 MW for Pacific Gas & Electric to 245 MW with Southern California Edison.
Honorable Mentions
Hastings Hydrokinetic, Hydro Green Energy and the City of Hastings, Minn.
Hydro Green Energy’s Hastings hydrokinetic power plant is one of the first of its kind to receive an operating license from the U.S. Federal Energy Regulatory Commission and one of the only commercial hydrokinetic projects exporting electricity to the country’s power grid for sale. Hydro Green Energy operates its technologies in open rivers, at existing hydropower facilities, at lock and dam infrastructures, next to non-powered dams and in cooling water systems at thermal power plants.
The $2.6 million project, a partnership between the city of Hastings, Minn., and Hydro Green Energy LLC, began operations in April 2009. The project features a two-turbine project downstream from the city’s 4.4 MW run-of-river hydropower plant on the Army Corps of Engineers’ lock and dam. The two turbines have a nameplate capacity of 250 kW. Hydro Green Energy developed a patented technology that allows for power generation at existing non-powered lock and dam infrastructures. The technology is designed to be deployable in the cooling water discharge systems at thermal power plants for energy recovery or energy efficiency purposes.
Hydro Green Energy will perform water quality, fish survival, mussel and avian studies on the project.
Kimberlina Solar Thermal Energy Plant, Ausra, Bakersfield, Calif.
Kimberlina is one of the first solar thermal power plants to use compact linear Fresnel reflector (CLFR) technology in North America and among the first solar thermal plants to go online in California in 20 years. The CLFR solar collector and steam generator systems use modular flat reflectors to focus the sun’s heat onto elevated receivers, which consist of carbon steel tubes through which water flows. CLFR’s peak production coincides with peak demand times, bringing solar thermal energy at times when fossil-fired electricity is most expensive.
The systems generate steam directly without the need for an intermediate heat transfer fluid or binary steam cycle. Also, the optical precision required of the Fresnel lens is less than for a parabolic lens and it uses water as a working fluid instead of oil.
The primary focus of the 5 MW Kimberlina plant is as a testing facility for continued development of CLFR technology. The ability to meet a range of temperatures allows for broader application for CLFR including solar steam augmentation for coal- and gas-fired plants, solar hybrid gas-fired plants and stand-alone solar thermal power plants.
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