What is thermal efficiency of gas turbine?
When the gas turbine is used solely for shaft power, its thermal efficiency is about 30%. However, it may be cheaper to buy electricity than to generate it. Therefore, many engines are used in CHP (Combined Heat and Power) configurations that can be small enough to be integrated into portable container configurations.
What is the difference between boiler and HRSG?
Most of the HRSG’s are internally insulated so that expansion does not affect the external surfaces and the structures. Conventional boilers on the other hand are top supported and free to expand so the insulation is on the outside.
What is the most efficient gas turbine?
Today we announced that the Chubu Electric Nishi-Nagoya power plant Block-1 – powered by GE’s 7HA gas turbine – has been recognized by GUINNESS WORLD RECORDS™ as the world’s Most efficient combined-cycle power plant, based on achieving 63.08 percent gross efficiency.
At what exhaust temperature gas turbine releases before HRSG can generate steam?
The low exhaust gas temperature from gas turbines, typically ranging from 900 to 1050F, generates less steam on unit gas mass basis in the HRSG evaporator compared to a package boiler.
How do HRSG work?
An HRSG is a kind of heat exchanger that recovers heat from the exhaust gases of a gas turbine to an extreme degree. The heat is recovered in the form of steam which is served as the power source of a power-generating steam turbine.
Why is gas turbine efficiency low?
The decrease in the compressor airflow rate results in a decrease in the compressor power absorbed. Similarly, the reduction in the turbine flow also results in a decrease in turbine power. The compressor efficiency decrease is due primarily to the effects of compressor fouling.
How do you find thermal efficiency?
An Example. If 200 joules of thermal energy as heat is input (), and the engine does 80 J of work (), then the efficiency is 80J/200J, which is 40% efficient. This same result can be gained by measuring the waste heat of the engine.
What does an HRSG do?
Which powerplant has highest efficiency?
Guinness World Records has named the Chubu Electric Nishi-Nagoya power plant Block-1 in Japan — powered by GE’s 7HA gas turbine — the world’s most efficient combined-cycle power plant, based on achieving 63.08 percent gross efficiency.
How is the thermal efficiency of the HRSG expressed?
In a cogeneration application in which a portion of the recovered heat is passed on to process (QP), either directly from the HRSG or via extraction from the steam turbine, efficiency can be expressed as: The net fuel rate, or FCP equation, (developed in Chapter 2) applied to a combined-cycle cogeneration type system can be expressed as:
Why is heat recovery steam generator ( HRSG ) so demanding?
The Heat Recovery Steam Generator (HRSG) is a demanding environment. Insulation materials must be able to retain their strength and resistance to erosion, even in very high temperature conditions, and high velocity gas turbulence.
How are HRSG designs used in gas turbines?
HRSG designs have come a long way, particularly for large gas turbines. With multiple pressure level steam generation and multiple modules, the need to optimize the gas/steam temperature profile is obvious. Simulation helps to a great extent.
What is the thermal efficiency of a gas engine?
With a spark-ignited gas engine, featuring a simple-cycle efficiency of 39% (LHV basis) for example, exhaust temperatures in excess of750°F (399°C) can be produced. At an exhaust temperature of 788°F (420°C), for example, superheated steam at about 145 psig (11 bar) and 715°F (380°C) can be generated, allowing for a thermally efficient steam cycle.