Most operators require that a gas turbine can operate over a reasonably wide range of fuels. Specifically, in pipeline and gas field duty, there is an expectation that a gas turbine can operate over a significant Wobbe Index range.
Due to a multitude of technical reasons such as weight, size and considerable shaking forces, emergency piston type diesel generators cannot be included in a watertight building or be placed at an elevation high enough to protect them from flood waters.
The future of the Texas electric market will very likely include substantial amounts of renewable energy and gas-fired power, economists with The Brattle Group find in a new report prepared for the Texas Clean Energy Coalition (TCEC).
"Exploring Natural Gas and Renewables in ERCOT, Part II: Future Generation Scenarios for Texas" provides a 20-year outlook for natural gas and renewable power in Texas. It is the first examination of its kind to be conducted and shared publicly in Texas.
The U.S. Energy Information Administration's Annual Energy Outlook early release report says that projected low prices for natural gas make it a very attractive fuel for new generating capacity. In some areas, natural gas-fired generation replaces generation formerly supplied by coal and nuclear plants.
Georgia has an abundance of renewable power sources, such as hydro and wind. Georgia's grid network was not designed as a network for an independent state, as it was part of the power supply in the Caucasus that was linked to the Soviet republics.
Forecast International predicts sales of 1,072 gas turbines for electrical power production in 2014, increasing steadily to 1,300 units by 2023. The value of production will be $18.4 billion in 2014, rising to $22.3 billion by 2023.
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Coal-plant operators in the U.S. and Canada have announced plans to close a significant portion of their coal fleet. The following table contains a summary of coal plant retirements, by year of shutdown, tracked by Industrial Info. Data for 2010-2013 reflects actual plant closures while data for 2014-2017 shows the date of planned closures.
New-build coal generation has been severely curtailed in recent years, a victim of ever-toughening regulations on emissions, state and federal support for renewables, and the dramatic expansion of domestic natural gas supplies through horizontal drilling and hydraulic fracturing.
The 7EA User Group conference this year featured a rotor lifecycle roundtable where vendors and consultants answered questions regarding a TIL by GE indicating that 200,000 hours or 5000 starts were the end-of-life limits for the 7EA.
A steam turbine diaphragm is also a very difficult component to manufacture due to the following conflicting requirements:
- it consists of three major parts made from different materials;
- it must have exceptional mechanical strength;
A turbine diaphragm, due to its complex structure and harsh operating conditions, is a very difficult subject for mechanical strength calculations. Structural complexity of the diaphragm is characterized by the following features:
- It is a complicated 360 degree plate, composed of three major components (an outer ring, a set of vanes with complex geometry, and an inner ring) made from different materials;
- A diaphragm is always split in two halves;
- The outer ring is supported by its outer diameter;
- The inner ring is supported only by vanes.
Long term operation and extensive R&D of steam turbines have shown that steam leakages from the main steam flow beyond the rotating blade shrouds and their roots as well as between the shaft and diaphragm ID is the main source (75-81%) of turbine performance deterioration due to:
EEC is the axial distance between the vane exit edge and rotating blade inlet edge in each stage (Figure 1). EEC is an important factor that affects stage performance (both efficiency and reliability). The required EEC for optimal performance is dependent on whether or not the stage has effective tip and root seals.
This innovative design feature is applicable to several first stages operating with high steam conditions. High steam pressure and temperature results in high density steam. Small volumetric steam flow requires partial arc steam admission, short vanes and rotating blades.
A smooth and unimpeded steam flow entrance into the rotating blades, with proper distribution of steam along the heights of these blades, is one of the most substantial factors related to stage efficiency. Such a steam entrance is defined by the compound (axial and tangential) angle of the steam flow. The axial angle is achieved by the optimal va
Figure shows the comparison between the original and current airfoil designs. The old airfoils form a channel in which steam flow accelerates and turns to exit with maximum steam velocity resulting in high secondary losses.
Seal system issues are a common reason for alarms and shutdowns in turbocompressors. Upgrades to dry gas seal systems typically consist of two options:
• Seal gas filter system — the original filters are typically small in capacity and large in the mesh size. In most cases, new filters should be used which are 4-to-6 times bigger while having a mesh that is 5-to-8 times smaller
• Operation range of seal system instruments — seal panels are complex systems with various kinds of instrumentation.
The 42nd Annual Turbomachinery Symposium and 29th International Pump Users Symposium took place in early October in Houston, Texas. Almost six thousand attendees enjoyed aprogram consisting of short courses, tutorials, technical sessions, discussion groups and 325 exhibits.
Wood Group and Siemens AG have entered into an agreement to form a joint venture ("JV") consisting of the Maintenance and Power Solutions businesses of Wood Group GTS (excluding its Rolls Wood Group, TransCanada Turbines and Sulzer Wood joint ventures) and Siemens TurboCare business unit ("TurboCare") which provides aftermarket gas turbine, steam turbine and generator design, repair and manufacturing services.
As the quest for raw materials drives oil and gas companies further offshore, both risk and potential gains increase. At some point in offshore operations, it becomes nearly impossible to push oil and gas to the surface with the existing degree of natural pressure. Some hydrocarbons become non-recoverable due to the loss of pressure during production.