As the gas turbine industry continues to move towards increasingly advanced and efficient turbines, the costs of component maintenance and replacement continue to be a crucial factor for economic viability. Most strategic planning tends to be around the refurbishment and replacement of flow path components.
The use of natural gas as the fuel of choice for power generation suggests two possible driver technologies: gas turbines (GTs) and reciprocating gas engines (REs). Due to the range of output available, a 230 MW plant might consist of 13 to 25 RE units, or 1 x 230 MW GTs through to 16 x 15 MW GT units.
The U.S. Environmental Protection Agency estimated that industrial sources (agricultural, waste, and energy) emitted 323.5 million metric tons of methane into the atmosphere in 2005 alone. Methane is both a powerful greenhouse gas and a highly energy dense gas present in waste gases. Releasing large quantities of methane into the atmosphere is not only detrimental to the environment, but also a wasteful solution for an energy dense fuel. For this reason, governments are increasingly regulating methane emissions.
While gas-fired generation is up around the world, regional variations in the nature and extent of gas use are substantial. Siemens Energy's Living Energy magazine analyzes gas use in four regions to describe these variations.
NRG's Huntley coal-fired power plant in Tonawanda, New York, just outside of Buffalo, is experiencing average annual pre-tax earnings of a negative $1 million and "does not appear to be financially viable," according to a new Institute for Energy Economics and Financial Analysis (IEEFA) report requested by the Clean Air
The Grand River Dam Authority’s (GRDA) Board of Directors gave their unanimous approval for the selection of MPSA to supply a natural gas powered M501J Gas Turbine, SRT-50 Steam Turbine and associated electric Generators for installation at the proposed new Unit #3 at their existing power generation facility in Cho
Natural gas and oil production has gone way up the past few years here in the United States. A few years ago there were many skeptics who thought that the newly produced shale franking gas and oil production was only a bubble to soon pop, but now the experts all seem to agree that US gas and oil production is here to stay for the long run.
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.