Assessment of Organic Rankine Cycle Part-Load Performance as Gas Turbine Bottoming Cycle with Variable Area Nozzle Turbine Technology

Power cycles on offshore oil and gas installations are expected to operate more at varied load conditions, especially when rapid growth in renewable energies puts them in a load-following operation. Part-load efficiency enhancement is advantageous since heat to power cycles suffer poor efficiency at part loads. The overall purpose of this article is to improve part-load efficiency in offshore combined cycles. Here, the organic Rankine bottoming cycle with a control strategy based on variable geometry turbine technology is studied to boost part-load efficiency. The Variable Area Nozzle turbine is selected to control cycle mass flow rate and pressure ratio independently. The design and performance of the proposed working strategy are assessed by an in-house developed tool. With the suggested solution, the part-load organic Rankine cycle efficiency is kept close to design value outperforming the other control strategies with sliding pressure, partial admission turbine, and throttling valve control operation. The combined cycle efficiency showed a clear improvement compared to the other strategies, resulting in 2.5 kilotons of annual carbon dioxide emission reduction per gas turbine unit. Compactness, autonomous operation, and acceptable technology readiness level for variable area nozzle turbines facilitate their application in offshore oil and gas installations.

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Off-design performance analysis and optimization of the power production by an organic Rankine cycle coupled with a gas turbine in an offshore oil platform

Energy Conversion and Management ◽

10.1016/j.enconman.2019.06.051 ◽

2019 ◽

Vol 196 ◽

pp. 1037-1050 ◽

Cited By ~ 4

Author(s):

Max Mauro L. Reis ◽

Jorge Alejandro V. Guillen ◽

Waldyr L.R. Gallo

Keyword(s):

Performance Analysis ◽

Gas Turbine ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Power Production ◽

Design Performance ◽

Offshore Oil

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Combined Solar Thermal Gas Turbine and Organic Rankine Cycle Application for Improved Cycle Efficiencies

Volume 4: Ceramics; Concentrating Solar Power Plants; Controls, Diagnostics and Instrumentation; Education; Electric Power; Fans and Blowers ◽

10.1115/gt2013-94713 ◽

2013 ◽

Cited By ~ 1

Author(s):

Karsten Kusterer ◽

René Braun ◽

Linda Köllen ◽

Takao Sugimoto ◽

Kazuhiko Tanimura ◽

...

Keyword(s):

Gas Turbine ◽

Waste Heat ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Solar Thermal ◽

Water Steam ◽

Central Receiver ◽

Combined Operation ◽

Gas Turbine Cycle ◽

Cycle Efficiency

Concentrating Solar Power (CSP) technologies are considered to provide a significant contribution for the electric power production in the future. Different kinds of CSP technologies are presently in operation or under development, e.g. parabolic troughs, central receivers, solar dish systems and Fresnel reflectors. In such applications, electricity is produced by thermal energy conversion cycles. For high MW-class CSP applications usually water/steam cycles (Rankine cycles) are used. Alternative technologies, especially for central receiver applications, are open and closed gas turbine cycles (Brayton cycles), where higher receiver fluid outlet temperatures can be applied. Therefore, there is the potential of higher cycle efficiencies and the advantage of reduced water consumption. The paper presents the results for design considerations to improve a gas turbine cycle of a 2 MWel class industrial gas turbine for solar-thermal application, where solar heat is fed in by a central receiver technology. The reference process is improved significantly by application of an intercooler between the two radial compressor stages and a recuperator, which recovers heat from the exhaust gases to the compressed air before the air is further pre-heated by the solar receiver. Hybrid operation of the gas turbine is considered. In order to further improve the overall cycle efficiency, the combined operation of the gas turbine and an Organic Rankine Cycle is investigated. The ORC can be coupled to the solar-thermal gas turbine cycle at the intercooler and after the recuperator. Therefore, waste heat from different cycle positions can be transferred to the ORC for additional production of electricity. The investigations have been performed by application of improved thermodynamic and process analysis tools, which consider real gas behavior of fluids and a huge number of organic fluids for application in ORCs. The results show that by choice of a suitable organic fluid the waste heat recovery can be further improved for the investigated gas turbine cycle. The major result of the study is that by combined operation of the solar thermal gas turbine and the ORC, the combined cycle efficiency is approximately 4%-points higher than in the solar-thermal gas turbine cycle.

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Development of Offshore Gas Turbine Packages for Power Generation and Mechanical Drive

Volume 1A: General ◽

10.1115/80-gt-84 ◽

1980 ◽

Author(s):

B. G. Hulme

Keyword(s):

Power Generation ◽

Gas Turbine ◽

Gas Turbines ◽

Oil And Gas ◽

Arabian Gulf ◽

Structural Requirements ◽

Design Considerations ◽

Offshore Oil And Gas ◽

Offshore Oil ◽

Preferred Solutions

This paper describes the application of aero-derivative gas turbines for power generation and mechanical drive on fixed offshore oil and gas platforms. Established installation concepts are discussed and a comparison is made between two designs of pre-packaged power plant for installation on North Sea and Arabian Gulf platforms respectively. The structural requirements of such packages are analyzed and the design considerations for a Warren Truss structured machinery module are outlined. Some of the problems associated with installing packaged aero-derivative gas turbine machinery in the extremely aggressive offshore environment are highlighted and preferred solutions are proposed.

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