In spite of turbulent times, the US power industry was in buoyant mood at the recent Power-Gen International exhibition and conference. Concerns over energy security and the environment now seem to be the key drivers behind technological change.

Siân Green, Managing Editor

They say that Las Vegas was built on losers, but the 16000 industry professionals who gathered there in December for Power-Gen International were in search of success – or at least survival – strategies for the year ahead. Having weathered the storms – literal and metaphorical – of recent times, the US power industry has proven it is nothing if not resilient, and the mood at the event seemed positive and buoyant.

For the US power industry, 2005 was a year marked by high energy prices, hurricanes, and the long-awaited signing of the Energy Policy Act. Record oil and gas prices, exacerbated by a particularly bruising hurricane season, have thrown the spotlight on energy security, while the Energy Policy Act and other legislative developments have brought environmental issues to the fore.

The first unit of the new Waukesha APG Series, the APG1000 Enginator genset, is a 1 MW unit that extends the company’s high-speed product range to 800-1100 kW
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In a recent power industry survey carried out by Alstom, 90 per cent of respondents said that environmental issues are among their top three operational concerns. Carbon emissions are a big concern, said Philippe Joubert, president of Alstom Power, while other industry drivers include GDP growth and an aging fleet. Deregulation is no longer the driver that it was, said Joubert.

Mercury control

These trends are already being reflected in company strategy throughout the industry. Alstom says it is focussing on clean combustion, developing clean-burning technologies as well as those for post-combustion emissions capture. The company announced at Power-Gen that it has signed an agreement with German company Vosteen Consulting to market and sell a mercury control technology called KNX.

KNX is a bromine-based fuel additive that enhances the oxidation of mercury in coal-fired boilers, making it easier to collect in downstream air pollution control equipment such as FGD systems. The technology has already been demonstrated at several utility plants in North America and has also been commercially applied in some waste incineration plants in Germany.

GE Energy has also made progress on the mercury control front, announcing a new mercury monitoring system as well as participation in a $2.2 million project to evaluate mercury removal from bituminous coal fired power plants. In addition, the company continues to build on its ‘ecomagination’ initiative, adding its LMS100 simple cycle gas turbine and the Jenbacher coal mine methane product line to its list of ecomagination-certified products.

Capstone’s biogas-fueled CR65-ICHP has an integrated stainless steel heat recovery module. The C65 will replace Capstone’s C60 microturbine model
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GE has developed the new mercury continuous emissions monitoring system (CEMS) in partnership with PS Analytical to satisfy performance standards required by the Clean Air Mercury Rule. It employs Cold Vapour Atomic Fluorescence (CVAF) technology, which induces mercury atoms to fluoresce, enabling concentrations of mercury to be calculated.

In addition, GE Energy has been selected to lead a US Department of Energy (DOE) project to evaluate an integrated approach for removing mercury from power plants burning bituminous coal. The project’s objective is to demonstrate at least 70 per cent mercury reduction from current mercury emissions at the plant by optimising the performance of burners and mercury and NOx control systems to enhancing ‘natural’ mercury capture, improving fly ash reactivity by duct humidification, and the use of activated carbon injection.

Engines of growth

Another company striving to meet ever-stringent emissions limits is Caterpillar, which is rolling out its ACERT technology across its range of diesel engines for stationary power gensets. It announced at Power-Gen that a new line of engines equipped with ACERT is now available, covering the 225-1000 kW power range. ACERT technology enables Cat’s products to meet US EPA Tier 2 and Tier 3 stationary emission standards, and is the result of $500 million-worth of research by the company.

ACERT has been employed in Caterpillar’s on-highway engines, and has now been adapted for stationary power applications. In addition to lowering emissions, it brings the added benefit of a smaller footprint and higher power density. The technology employs a combination of integrated electronics, advanced air management and precise fuel delivery to optimise power and fuel economy.

Another company unveiling new engine technology was Waukesha Engine, whose new APG series was introduced at Power-Gen. The APG Series is aimed at the power generation market, and employs advanced lean burn combustion, a new high energy ignition system, fast burn rate and a new high efficiency turbocharger. “The APG Series is a bridge between the robust Waukesha Engine design that has been so highly valued by our traditional customer base and the state-of-the-art technology required by the power generation market,” said Paul Cannestra, vice president of marketing for Waukesha Engine.

The first unit of the APG Series, the APG1000 Enginator genset, is a 1 MW unit that extends Waukesha’s high-speed product range into the 800-1100 kW range. It has been developed in cooperation with the US DOE as part of its Advanced Reciprocating Engine Systems (ARES) programme, created to accelerate the development of large natural gas engines.

Microturbine model

Further developments in the distributed generation sector were shown by companies such as Capstone Turbine Corporation, which announced that it will this month start to ship its new C65 microturbine model. The natural gas fuelled 65 kW C65 unit will replace the C60 model, offering an 8.5 per cent increase in output, a four per cent increase in efficiency and a 45 per cent reduction in NOx output over its predecessor, but with the same footprint.

The new Siemens SGT5-8000H gas turbine. With a capacity of 340 MW, this machine will be the world’s largest and most powerful gas turbine
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Capstone will also introduce a variation of the C65 that will use waste flare gases from landfills or sewage treatment plants as fuel. The CR65 (‘R’ for renewable) will be available with an optional stainless steel integrated heat exchanger.

Micro to macro

Siemens power generation took the opportunity at Power-Gen to reveal more details of its SGT5-8000H gas turbine technology, initially unveiled in September 2005 (see PEi October 2005, Analysis, p5). The 340 MW gas turbine will be the largest and most powerful in the world, and has been designed to operate with a simple cycle efficiency of 39 per cent and a combined cycle efficiency of 60 per cent.

Siemens revealed that the SGT5-8000H will be 13.1 m long, 5.2 m in diameter, and will weigh nearly 440 t. It will initially be aimed at the 50 Hz power markets in Asia and Europe, running on natural gas or fuel oil. However, it will be further developed to operate in special applications such as IGCC.

The rotor and compressor design will provide a platform for future gas turbine models, says Siemens, which has been testing the new compressor at its manufacturing plant in Berlin since January 2005.

Siemens also revealed that the turbine will be air-cooled. This will simplify the design of the plant as well as provide operators with greater operational flexibility, shorter start-up times and faster load changes than other existing gas turbines in its class. The air-cooled design will be enabled by the use of new coatings, says Siemens. The SGT5-8000H will be the first air-cooled unit to achieve 60 per cent efficiency in combined cycle operation.

Power-Gen International news roundup

Expanding its mission of helping users prevent costly plant shutdowns, Emerson Process Management has introduced a CSI 4500 Machinery Health Monitor application that provides live, continuous monitoring of turbines used for main power and other critical processes during transient conditions. This new condition monitoring technology supports predictive and proactive maintenance by presenting data for asset management decision making. It is a component of Emerson’s PlantWeb digital plant architecture and provides vital information necessary to prevent catastrophic failure. Emerson also revealed that “Partnering for Power” – a comprehensive strategy that identifies opportunities for improving the performance and efficiency of generation assets – is fueling measurable operational improvements for utilities across the USA. To date, more than 20 utilities have achieved tangible results – such as improved heat rate and environmental compliance, optimal fleet management, increased ramp rates and lower maintenance costs – translating into millions of dollars in savings.

WahlcoMetroflex, a worldwide leader in the design and manufacture of dampers, expansion joints and systems for isolating and controlling gas flows, announced its Flex-Seat guillotine damper for the isolation of gas flows in the most extreme operating conditions. This fully bonneted guillotine damper provides high performance and simplified maintenance to meet the needs of combustion and hot gas systems of all kinds, including power plants, refineries, chemical plants, pulp and paper mills, metallurgical smelters, steel mills and incinerators.

GE Energy announced two new offerings to its OpFlex product line, designed to provide customers greater operational flexibility to respond to market conditions while reducing environmental impacts. The first – OpFlex Startup NOx – was developed to reduce NOx emissions during startup, low-load operation of 7F gas turbines with DLN 2.6 combustors. The second – Startup Fuel Heating – applies more advanced turbine controls logic to exploit previously unexplored capabilities in the combustion system. This reduces pauses during the start sequence while waiting for the fuel to reach rated fuel temperature.