After years of testing and installation in other power plants in different parts of the world, GE Energy has now incorporated its H-System gas turbine technology into a U.S.A.-based power plant located in the unincorporated community of Romoland in Riverside County, California. The power plant, called the Inland Empire Energy Center LLC, will supply the electricity needs of almost 600 000 households and businesses in the area when complete.

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An aerial view of the 775 MW Inland Empire Energy Center located in Riverside County, California, U.S.A. The 18 hectare site is the home of the first GE Energy H-System gas turbine plant in the United States. The plant includes two Frame 7H 60 Hz gas

The Inland Empire Energy Center (IEEC) will incorporate two, natural gasfueled,GE 107H combined-cycle power blocks for a total maximum net rated electrical output of 775 MW. This marks the first installed application of the H System gas turbine technology in a 60 Hz machine, as well as the first installation in the U.S.

The previous H System machines, one installed at Baglan Bay Power Station in South Wales (see D&GTW, December 2003) and others in Japan at Tokyo Electric Power Company’s Futtsu Thermal Power Station Group 4 project (see D&GTW, May 2007), are 50 Hz, Frame 9 machines.

The Baglan Bay facility has now surpassed 26 000 hours of operation, while the first three 109H combined-cycle systems at Tokyo Electric Power will enter service in 2008. The H System gas turbines are said to be capable of reaching 60% thermal efficiency when operating at the rated combine-cycle mode.

“GE took its time in finding a site for the first 60 Hz machine,” said John Gates, H System Asset Management commercial manager. “Several sites were considered, including one in Canada, but GE wanted to find just the right location to showcase the technology and provide additional feedback for future product development.

“The three H System power plant locations are geographically diverse and include different ambient climate conditions, environmental restrictions and other operating conditions. This allows GE to gather an increased volume of operating experience on the H System,” continued Gates.

GE is financing, and will own the IEEC. GE Power Systems and Calpine Power Services are managing plant construction,and Calpine Energy Services will market the plant’s output and manage fuel requirements under a longterm marketing arrangement with GE. Following an extended period of GE ownership, Calpine expects to purchase the plant and become its sole owner and operator, with GE continuing to provide plant operation and maintenance services under a contractual agreement with Calpine. Southern Cal Edison will assist with the distribution of power to the surrounding area. With this arrangement, it should be noted that the only H System technology currently in private hands are the units at the Tokyo Electric Power Co. plant in Japan.

This is the largest private investment so far in Riverside County history, according to Gates. It will be a base load plant that will fire at maximum capacity in the peak times and will operate at minimum load during offpeak times. The IEEC is set on about 18 hectares of land.

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A view of the inlet air ducting system and filtration housing for one of the Inland Empire Energy Center’s two GE Frame 7H gas turbines.

IEEC was originally permitted by Calpine in 2003 as a green field project for a facility with different equipment.

GE bought the permitted site in February of 2005 to develop the facility for the H System equipment. According to Gates, the site has turned out to be a great fit for the H System. The site was already permitted for a power plant, and much of the infrastructure was already in place nearby — including a water supply, a 500 kV transmission sub-station, and a natural gas supply pipeline. “The existence of some of the basic infrastructure before the project began has helped with the development of the facility,” said Gates. “Those basic, but key pieces of infrastructure reduced the complexity, cost and scope of the project.”

One key to GE locating the plant here is the area’s need for electric power. The Riverside-San Bernardino, California, area, a far eastern suburb of Los Angeles known as the “Inland Empire,” is growing at a tremendous pace. At the time of writing, the area was ranked as the fourth hottest job market in the United States according to a published City Business Journals study.

In addition, Riverside and San Bernardino counties have become the focal point for development of product distribution centers for nearly half the goods coming through the ports of Long Beach and Los Angeles that lay about 113 km to the west of the IEEC.

“The area simply needs more electric power,” said Gates. “The electricity demand curve in California is rising.” Other reasons GE chose the location, according to Gates, are the strict environmental restrictions and the different climate compared to the first H System projects.

Each of the two power blocks includes a GE Frame 7H gas turbine driving a Toshiba TAKS ICH 455 Mva hydrogen-cooled generator and a Toshiba steam turbine. The turbines are connected to a TAS F-70 gas turbine inlet air-chilling package designed and provided by Turbine Air Systems to GE specifications. The system is engineered to increase the power and efficiency of the plant by using inlet coils that will be chilled by two duplex, water-cooled chillers piped in a series arrangement.

The air inlet and filtration housing is provided by Donaldson and includes an automatic self-cleaning pulsation feature. A fuel moisturizing system and Atlas Copco gas compressor for boosting turbine fuel pressure is also included. The Heat Recovery Steam Generator (HRSG) is supplied by Deltak, the three pressure reheat configuration provides steam for the steam turbine and also provides heat for fuel heating and moisturization.

A selective catalytic reduction (SCR) system using aqueous ammonia as the reactant and a carbon monoxide catalyst are also incorporated into each exhaust path to reduce NOx and CO emissions, respectively. The plant includes the continuous emissions monitoring system (CEMS) required by the South Coast Air Quality Management District (SCAQMD).

The environmental restrictions to which the IEEC is held are tough. It meets CEC and SCAQMD requirements for NOx and CO. The NOx limit is 2 ppm at 15% O2 dry air when fueled by natural gas at base load levels. The CO limit is 3 ppm at 15% O2 dry air. In addition, volatile organic compounds (VOCs) are 2 ppm at 15% O2 dry. The ammonia slip (NH3) 5 ppm at 15% O2 dry air.

The first gas turbine to arrive, Unit #1, is expected to achieve first firing by the end of this year, while Unit #2 will be fired in early 2008. Unit #1 is fully instrumented for R&D purposes and will undergo extensive validation testing throughout the first half of 2008. Once fully operational, the instruments will be removed.

“This follows the same pattern that was used at Baglan Bay during its first firing and subsequent commercialization,”said Gates. “With equipment like this, especially something new like the H System, we want to make sure all the systems are operating without problems, and we also want to generate a baseline of data on the operation of the equipment during the validation phase.”

IEEC is an external plant in that most all of the operating equipment is exposed to ambient conditions or is only lightly sheltered. This design meets the region’s requirements and includes noise attenuation panels incorporated into the structures around the turbines and other balance of plant equipment, according to Gates. The buildings at the facility include the power distribution center complete with plant control room, offices, welcome center, a maintenance facility and warehouse, and the GE-designed water treatment plant.

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Shown here is a view of the massive Heat Recovery Steam Generator (HRSG) system that is part of a power block at the Inland Empire Energy Center.

The control room has ample space for the two operators and one superintendent. Once complete and operational, five people will be stationed at the plant 24 hours per day, seven days a week. The plant will use GE’s Mark VI control system and GE/Prolec transformers to move the electricity from the plant. The GE-designed demineralization water treatment plant, which was recently commissioned, will supply demineralized water, purified from recycled water feedstock, to provide all needed steam plant makeup water for the entire site operation.

The recycled water comes from the city water treatment plant. The plant cooling system includes SPX Cooling Technologies cooling towers with eight cells per gas turbine. Included in the package are Marley fans to keep air circulation constant and two pumps per unit to keep the water circulating. Recycled water is the major water source of the plant. The plant includes 8 million L worth of recycled water-tank storage capacity.

There are also two Caterpillar-powered diesel essential service generator sets — one per turbine — that provide power for auxiliary functions necessary to maintain the plant in a “ready to start” condition in the event of a loss of off-site power.

Recently, back feed power was provided to one of the two gas turbines at the site, allowing the start-up and commissioning of the power plant auxiliary systems. In addition, the GE-designed demineralization water system is being commissioned. Plant operation is expected to begin in time to help offset state-forecasted electricity shortfalls in the area next summer.

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