February 15, 2008

Global Monitor (February 2008)

POWER digest

News items of interest to power industry professionals.

Oxy-combustion tests show promise. Babcock & Wilcox Power Generation Group (B&W PGG) has reached a major milestone on the road to commercializing a new technology that could greatly reduce CO₂ emissions from new and existing coal-fired power plants.

B&W PGG became the first in the world to burn coal in full oxygen-combustion mode at a 30-MW_t scale during recent testing at its Clean Environment Development Facility (CEDF) in Alliance, Ohio. The CEDF operated in full oxygen-coal combustion mode for over 250 hours as it burned more than 500 tons of bituminous coal.

As the name implies, B&W PGG’s oxygen-coal combustion process uses oxygen, rather than air, to fire coal. Doing so keeps nitrogen out of the process, and as a result its exhaust gas is mostly relatively pure CO₂, rather than a mix of nitrogen oxides and other pollutants. Furthermore, the exhaust gas has less volume, is easier to capture, and with further purification is ready for sequestration or injection into wells to enhance oil recovery.

Working closely with B&W PGG on this project was American Air Liquide, which provided the oxygen, engineering, and chemistry expertise related to combustion as well as the equipment and sensors needed for safe and efficient handling of the liquefied oxygen used during testing. An Oxy-Coal Combustion Advisory Group representing utility and merchant power generators also actively participated in the testing process.

B&W PGG will continue its oxy-coal combustion research at the CEDF through the second quarter of this year. Next up on the development schedule are tests of the process on subbituminous and Powder River Basin coals and lignite.

B&W PGG is currently seeking interested parties to conduct further oxy-coal combustion testing at a demonstration plant large enough to capture more than a million tons of CO₂ annually. The Oxy-Coal Combustion Advisory Group will help B&W PGG evaluate applicants and select a site for this large-scale demonstration.

FERC licenses first wave energy pilot. The Federal Energy Regulatory Commission has issued the first U.S. license for a wave energy plant. It will operate as a pilot project for five years to demonstrate the potential—and work out the technical and environmental kinks—of the technology, which converts the kinetic energy of waves into electricity.

FERC said the 1-MW Makah Bay Offshore Wave Pilot Project off the shore of northwest Washington will be torn down after five years, as proposed by the developer, Finavera Renewables Inc.

Finavera Renewables’ planned offshore power projects consist of patented wave energy converters based on proven, marine buoy technology. Clusters of these modular devices, called AquaBuOYs, will be moored several miles offshore, where waves are taller than they are close to shore.

The project will consist of four steel buoys, each capable of producing 250 kW by harnessing the up-and-down motion of waves to drive power-generating equipment. The power will be sent to shore through a 3.7-mile underwater transmission cable that will be hooked into the distribution system operated by the Clallam County Public Utility District.

A cluster of AquaBuOYs would have a low silhouette in the water. Located several miles offshore, the wave power project arrays would be visible enough to allow for safe navigation but would be no more noticeable than a small fleet of fishing boats.

FERC has touted the potential benefits of bringing hydrokinetic projects on-line, saying that they could double the nation’s share of hydro capacity from its current 10% to 20%.

GE shortens turbine start-up time. GE Energy recently introduced a 10-minute start capability for its Frame 7FA gas turbines as an expansion of the company’s OpFlex gas turbine technology program.

When equipped with the feature, a 7FA gas turbine would achieve stable combustion and be ready for dispatching 10 minutes after receiving a start signal. During the start-up period, NO_x and CO emissions would both be less than 9 ppm. When incorporated into GE’s next-generation Rapid Response combined-cycle power plant design, the feature would reduce the start-up emissions of a 207FA system (two gas turbines and one steam turbine) by as much as 20% and increase starting efficiency by up to 30%. Targeted for 60-Hz markets, the fast start-up feature will be available for simple-cycle applications in 2009 and for combined-cycle operation in late 2010.

“A power company using GE’s Rapid Response combined-cycle power plant design with 10-minute start capability can provide high-efficiency power when it is needed most,” said John Reinker, general manager of GE Energy’s heavy-duty and combined-cycle gas turbine product line. “It is designed for customers who want to extend operation under an emissions cap, are contemplating cyclic duty, or have an opportunity to tap into additional revenue from the ancillary market.”