O&M

Performing regular oil changes on remote generators is far from simple or cost-effective. Here’s how one firm harnessed technology to extend oil change intervals from one week to two months.

The welding of dissimilar metal joints in new and retrofit power plant boiler tubing has long proved challenging. New plants designed to operate at higher temperatures and pressures require advanced alloys and a filler metal that produces reliable welds. EPRI recently developed and sponsored the commercialization of a new filler metal. Its first application is the fabrication of boiler tubes for American Electric Power’s ultrasupercritical John J. Turk, Jr. Power Plant.

Increasingly fierce competition driven by deregulation and privatization is putting downward pressure on power plant operations and maintenance (O&M) budgets. Recently, lower natural gas prices have pushed natural gas – fired combined-cycle plants higher up in many utilities’ dispatch order in some regions, a welcome change from the twice-a-day cycling experienced by some plants during the past few years. However, with more operating hours comes more interest in plant operating availability, and that means increased emphasis on reliable gas turbine operation.

Despite being located on the beautiful Hawaiian island of Oahu, the Kalaeloa Cogeneration Plant had trouble in paradise: Large amounts of ash from #6 low-sulfur fuel oil coated the finned tubes of its heat-recovery steam generators (HRSGs). The fouling added an extra $5 million dollars a year to the plant’s fuel bill. By retrofitting the HRSG with new panels and improved fin design, the plant overcame the fouling problems, stopped tube leaks, and cut fuel costs.

From the onset of the civilian nuclear era (marked by President Dwight Eisenhower’s "Atoms for Peace" speech to the United Nations in 1953), there has been a strong awareness of the importance of safety within the nuclear energy industry. Western experts have devoted much time and effort to ensuring the integrity of reactor cores and […]

Southern California Edison’s (SCE) 2,250-MWe San Onofre Nuclear Generating Station (SONGS) recently took receipt of a new and upgraded generator rotor for one of its two Alstom steam turbine generator units (Figure 1). Following the successful installation and flawless start-up of this new rotor in the Unit 2 generator, the former Unit 2 rotor was […]

In the wake of the recent U.S. Supreme Court ruling related to cooling water intake practices at large power plants, many utilities are relieved to be off the hook as far as implementing expensive control upgrades to protect fish and other aquatic organisms.

Combustor design simulation requires the resolution of complex geometry, turbulent flow patterns, heat transfer, and detailed chemistry. Although computational fluid dynamics (CFD) can simulate the reacting flow in realistic geometries, it requires the use of severely restricted chemistry models that are too simple to accurately simulate emissions and operational stability. A new simulation tool is now available that eliminates this CFD shortcoming while significantly reducing computing time.

Turkey’s growing power market has attracted investors and project developers for over a decade, yet their plans have been dashed by unexpected political or financial crises or, worse, obstructed by a lengthy bureaucratic approval process. Now, with a more transparent retail electricity market, government regulators and investors are bullish on Turkey. Is Turkey ready to turn the power on?

Organic compounds can enter the steam cycle from a number of sources, including water treatment chemicals, or as part of a manufacturing process. Regardless of the source of the organics, their effects range from fouling polisher resins to causing significant steam turbine damage. Conventional water pretreatment systems are available to remove organics from water, but removing organic compounds at their source is the best place to start addressing the problem.

Obtaining accurate data about the performance of a plant’s heat-recovery steam generator is crucial to ensuring the smooth operation and maintenance of the equipment. Software designed to model and simulate HRSG operations can provide valuable information about corrosion and other operational problems.

Recent improvements in the performance of steam power plants have been achieved with advanced computerized controls. These new control schemes not only reduce fuel consumption and make the plant much more responsive, but they also can significantly decrease start-up commissioning time and cost.

Measuring combustion airflow in a coal-fired power plant can be problematic when using annubar instruments that feature small holes that can easily plug with coal dust. Sierra Instruments eliminates this big maintenance headache with its more-accurate, nonplugging thermal mass flow meter design.

On January 8, 2007, a hydrogen explosion at the Muskingum River Power Plant’s 585-MW coal-fired supercritical Unit 5 caused one fatality, injuries to 10 other people, and significant damage to several buildings. The explosion occurred during a routine delivery of hydrogen when a hydrogen relief device failed, which allowed the contents of the hydrogen tank to escape and be ignited by an unknown source. This article covers the findings of the incident investigation and the actions the plant has taken to prevent a reoccurrence.

Boilers have enormous thermal mass and are relatively slow to react. Turbines are nimble and quickly answer an operator’s command. Coordinating an entire plant requires an intimate knowledge of both systems and selecting the right logic tools to bring them together.

Hydrokinetic energy — which generates power by using underwater turbines that harness moving water — is on the rise in the U.S. In January, the first U.S.-licensed, commercial, grid-connected hydrokinetic project installed the first of two 100-kW nameplate-rated turbines downriver from an existing run-of-river hydroelectric plant on the Mississippi River.

It may seem counterintuitive, but fire can be a serious danger in hydropower plants. In some respects, the danger is even greater than in thermal power stations. Most U.S. hydro plants are 30 to 70 years old but can deliver another 20 or 30 years of service with upgrades — including state-of-the-art fire protection systems. The design options outlined here also apply in large part to other generating stations.

This article discusses planning, operation, and documentation procedures designed to effectively use the thermal imaging camera as a critical element in an effective reliability program.

Radioactive materials are clinging to the inside walls of reactor system components because of a noble metals injection process error some years ago at Cooper Nuclear Station (CNS). CNS has launched an aggressive, long-term program to remove the materials, but until the work is successfully completed, the station is also taking extensive measures to protect employees and reduce higher source term dose.

Conventional wisdom tells us that the key to good boiler combustion requires carefully balancing the fuel-air ratios across all the coal pipes. Recent tests show that the uniformity of the burner-to-burner stoichiometries—not balanced pipe-to-pipe fuel flow distributions—dictates combustion uniformity.

Many coal-fired power stations built before 1980 were designed for handling relatively easy-handling lump coal. If your plant’s bins, bunkers, and silos aren’t up to dealing with today’s range of more variable coal properties, this case study shows one way to minimize coal flow problems.

Pulverizer throughput is determined by the coal fineness desired for a given coal. However, compromising on coal fineness when your pulverizer isn’t up to snuff can increase NO _x and cause many furnace problems. Your least costly option for increasing pulverizer capacity is to pay careful attention to key dimensions and critical tolerances during your next overhaul.

This guide offers suggestions from a control system engineering perspective for protecting power-generating units that are determined to be critical cyber assets

The unfortunate coal ash spill at the Tennessee Valley Authority’s (TVA’s) Kingston Fossil Plant that occurred on December 22 has heightened national awareness of the problems associated with utilities’ coal ash surface impoundments if they are not properly maintained.

New wireless technologies for power plant instrumentation offer significant cost savings when compared to traditional wired networks. The value of this cost savings is especially relevant in the highly competitive power industry, where aging facilities are common and upgrades are an expensive necessity. Modern wireless networks offer a reliable upgrade path that even provides some unexpected benefits when compared to traditional copper networks.

Tuning power plant controls takes nerves of steel and an intimate knowledge of plant systems gained only by experience. Tuning controls also requires equal parts art and science, which probably is why there are so few tuning experts in the power industry. In Part I of a two-part series, we explore a mix of the theoretical and practical aspects of tuning boiler controls.

By now, most electric industry participants are aware of the mandatory reliability standards required by the Energy Policy Act of 2005 and managed by the North American Electric Reliability Corp. (NERC). Bulk-power system users, owners, and operators (known as NERC registered entities) are responsible for complying with the set of standards that are applicable to their operations in their specific region. Compliance is monitored by the NERC regions (Texas Regional Entity, Western Electric Coordinating Council, Reliability First Corp., Midwest Reliability Organization, SERC Reliability Corp., Florida Reliability Coordinating Council, Northeast Power Coordinating Council, and Southwest Power Pool) through spot checks, self-certifications, audits, and investigations.

Nearly 10% of boilers and pressure vessels inspected in the second quarter of 2008 were slapped with violations, which means that the violations put workers and equipment in danger, according to a quarterly report released by the National Board of Boiler and Pressure Vessel Inspectors.

Wear and leakage are common maintenance problems that result in pump discharge pressure dropping below optimum levels and reduced pump efficiency. Converting pumps to mechanical seals eliminates fretting or grooving of the shaft and provides for easier pump maintenance. By converting to mechanical seals, a plant also avoids incurring expenses associated with the replacement of sleeves and shafts.

Most forecasting reports concentrate on political or regulatory events to predict future industry trends. Frequently overlooked are the more empirical performance trends of the principal power generation technologies. Solomon & Associates queried its many power plant performance databases and crunched some numbers for us to identify those trends.