Features

August 1886 POWER reported on one of the first twin-cylinder "Otto" natural gas–fired engines that had recently appeared in the U.S. power market. The report notes that "engines of 100 horsepower are being now economically used where gas is low in price, as in England and other European countries" (Figure 1). 1. A twin-cylinder "Otto" […]

The Northern Wood Power Project permanently replaced a 50-MW coal-burning boiler at Public Service of New Hampshire’s Schiller Station with a state-of-the-art fluidized-bed wood-burning boiler of the same capacity. The project, completed in December 2006, reduced emissions and expanded the local market for low-grade wood. For planning and executing the multiyear, $75 million project at no cost to its ratepayers, PSNH wins POWER’s 2007 Marmaduke Award for excellence in O&M. The award is named for Marmaduke Surfaceblow, the fictional marine engineer/plant troubleshooter par excellence.

By design, combined HP-IP turbines have a small amount of internal leakage from the high-pressure turbine to the intermediate-pressure turbine. As turbines age, the leakage increases considerably and becomes excessive, creating a heat rate penalty and possibly a reliability problem. Last month we explored the symptoms and causes of steam leakage within GE steam turbines and how to correct the problem. In Part II, we examine the same issues for Westinghouse and Allis-Chalmers turbines from both theoretical and practical angles.

With U.S. mercury regulations pending and control technologies in the full-scale demonstration stage, accurate and reliable measurement of mercury in flue gas is becoming more important than ever. This article compares the results of field measurements of commercially available mercury monitors to approved reference methods. A key but not-so-surprising finding: Not all mercury monitors are created equal.

Several states have mandated faster and/or deeper reductions in plant mercury emissions than those called for by the Clean Air Mercury Rule. Unfortunately, differences between plants make accurate evaluation of control options difficult. In most cases, even statistically based Hg emission models don’t pass muster because they don’t account for the dynamic chemical behavior of Hg species in gas cleaning systems. This article describes one system evaluation tool that has been validated using Hg field test data from 50 full-scale flue gas cleaning systems. It is already being used by TVA and other utilities.

The intended use is the primary consideration (even fuel is secondary) when choosing an on-site energy system. Whether the need is for power alone or for heat as well, distributed generation plants have delivered lower energy costs and improved reliability to industrial and commercial customers worldwide. Following are six case studies of reciprocating engine systems that highlight their versatility.

By design, combined HP-IP turbines have a small amount of internal leakage from the high-pressure turbine to the intermediate-pressure turbine. When turbines are new, the amount of this leakage is close to the design heat balance. But as turbines age, the leakage increases considerably, causing a heat rate penalty and possibly a reliability problem. In Part I, we explore the symptoms and causes of excessive leakage within GE steam turbines and how to correct the problem. Part II, in next month’s issue, will examine the same issues for Westinghouse and Allis-Chalmers turbines.

Scientific debate on the validity of global warming science continues, but the issue has yet had little impact on individuals. That impact is being negotiated in Washington, where a regulatory framework that would mandate reductions of greenhouse gases (GHGs) is taking shape. Legislative options under consideration would redefine what power plants must do-and not do-to […]

There are often five stages to enacting major legislative reforms: Initial enthusiasm, a sobering recognition of the complex issues to be solved, excruciating negotiations over those issues, hand-to-hand combat with supporters of the status quo, and resignation that the final product only deals with part of the problem. Congress has reached Stage 2 as it considers a cap-and-trade system for reducing carbon emissions. Now the real work begins.

When injuries or accidents occur, the employer ultimately loses on two counts: increased medical costs and employee absences. A policy of "safety, compliance, and then production" is more than just good business; it’s also good stewardship of the health and safety of employees who deserve no less.