Mohammad Mansouri Majoumerd

Thermodynamic Analysis of Innovative Micro Gas Turbine Cycles

The growing global energy demand has been faced with increasing concerns about climate change over recent decades. In order to cover the additional demand and to mitigate CO2 emissions, one option is to utilize renewable energies such as solar and wind power. These energy sources are, however, intermittent by nature. Therefore, it is inevitable that a quick balancing and back-up power should be available to maintain grid stability at a certain level.Gas turbine (GT) technology could certainly be one alternative for back-up/balancing power and could be utilized to complement renewable energy in the energy market. However, the GT industry needs to consider innovative cycle configurations to attain higher system performance and lower emissions and to cope with renewable powers. In this regard, the humid air turbine (HAT) cycle and the exhaust gas recirculation (EGR) cycle are amongst the promising GT cycles.In the current study a micro gas turbine (MGT), a Turbec T100, has been selected as the base case for further investigation. A thermodynamic model for the base case has been developed in IPSEpro software and validated using experimental data obtained from an existing test facility in Stavanger, Norway.Based on this validated model, system performance calculations for other alternative cycles, i.e. EGR and HAT cycles, have been carried out. Results confirm that the performance improvement potential is significant for the HAT cycle with only minor modifications to the baseline MGT cycle. The EGR cycle, with a maximum attainable recirculation ratio of 50%, shows a slightly lower level of performance compared to the base case. However, its potential for future CO2 capture is greater compared to the base case and the HAT cycle. The overall cycle efficiencies for the base case, the HAT, and the EGR cycles at full load operation, i.e. 100kW power, are 31.1%, 32.8%, and 30.4%, respectively.Copyright

A CCGT Based Polygeneration Using Rice Straw: Simulation by Aspen Plus®

Demand of secondary energy is ever increasing. Presently, fossil fuels supply majority of it. Energy technologists are currently facing the formidable challenge of meeting this demand with minimum environmental impact, specifically reduced CO2 emission to minimize ‘climate change’. Also new technology development for efficient energy conversion is needed for renewable resource (e.g. biomass) utilization. Rice straw is an agricultural residue and has good calorific value to be used as an energy resource. For the efficient utilization of rice straw, combined cycle gas turbine (CCGT) based polygeneration is a possible option to deliver multiple utilities. In this paper, a polygeneration plant is proposed to deliver power, cooling, heating and desalinated water. It was simulated by Aspen Plus®. Results show that polygeneration has good potential in power generation as well as for various other utilities. Effects of gasification parameters and gas turbine compression ratio are also studied. Results show that optimum equivalence ratio is 3.5–4 for maximum fuel energy savings ratio and for maximum exergy efficiency. Higher GT-cycle compression ratio results more power output but other utility outputs decrease with increase in compression ratio.Copyright

Impact of Fuel Flexibility Needs on a Selected GT Performance in IGCC Application

As part of a European Union (EU) funded H2-IGCC project, a baseline IGCC power plant was established; this was presented at the ASME Turbo Expo 2011 (GT2011-45701). The current paper focuses on a detailed investigation of the impact of using various fuels considering different operating conditions on the gas turbine performance, and the identification of technical solutions for the realization of the targeted fuel flexibility.Using a lumped model, based on real engine data, compressor and turbine maps of the targeted engine were generated and implemented into the detailed GT model made in the commercial heat and mass balance program, IPSEpro. The implementation was done in terms of look-up tables. The impact of fuel change on the gas turbine island has been investigated and reported in this paper. Calculation results show that for the given boundary conditions, the surge margin of the compressor was slightly reduced when natural gas was replaced by hydrogen-rich syngas. The use of cleaned syngas instead of hydrogen-rich syngas resulted in a considerable reduction of the surge margin and elevation of the turbine outlet temperature (TOT) at design point conditions, when keeping the turbine inlet temperature (TIT) and compressor inlet mass flow unchanged. To maintain the TOT and improve the surge margin, when operating the engine with cleaned syngas, a combination of adjustment of variable inlet guide vanes (VIGV) and reduced TIT was considered. A parameter study was carried out to provide better understanding of the current limitations of the engine and to identify possible modifications to improve fuel flexibility.Copyright

System Integration and Techno-Economy Analysis of the IGCC Plant With CO2 Capture: Results of the EU H2-IGCC Project

The overall goal of the European co-financed H2-IGCC project was to provide and demonstrate technical solutions for highly efficient and reliable gas turbine technology in the next generation of integrated gasification combined cycle (IGCC) power plants with CO2 capture suitable for combusting undiluted H2-rich syngas.This paper aims at providing an overview of the main activities performed in the system analysis working group of the H2-IGCC project. These activities included the modeling and integration of different plant components to establish a baseline IGCC configuration, adjustments and modifications of the baseline configuration to reach the selected IGCC configuration, performance analysis of the selected plant, performing techno-economic assessments and finally benchmarking with competing fossil-based power technologies.In this regard, an extensive literature survey was performed, validated models (components and sub-systems) were used, and inputs from industrial partners were incorporated into the models. Accordingly, different plant components have been integrated considering the practical operation of the plant. Moreover, realistic assumptions have been made to reach realistic techno-economic evaluations.The presented results show that the efficiency of the IGCC plant with CO2 capture is 35.7% (lower heating value basis). The results also confirm that the efficiency is reduced by 11.3 percentage points due to the deployment of CO2 capture in the IGCC plant. The specific capital costs for the IGCC plant with capture are estimated to be 2,901 €/(kW net) and the cost of electricity for such a plant is 90 €/MWh.It is also shown that the natural gas combined cycle without CO2 capture requires the lowest capital investment, while the lowest cost of electricity is related to IGCC plant without CO2 capture.Copyright

Intelligent Biogas Fuelled Distributed Energy Conversion Technologies: Overview of a Pilot Study in Norway

It is foreseen that distributed power generation, using biogas and natural gas as fuel, will play increasingly important role in the future European energy market. These technologies are presenting controllable power generation capacity as complementary to the installed intermittent renewable power generation in terms of wind and solar.A nationally funded project was initiated in Stavanger, Norway in 2010, led by the Center for Sustainable Energy Solutions (cenSE), to investigate use of existing small scale energy conversion technologies developed for natural gas, using as much as possible biogas mixed with natural gas without any hardware modifications to the energy conversion units. Three test setups with a micro gas turbine (100 kWe), a gas engine (11 kWe) and a short stack of solid oxide fuel cell consisting of six cells (30–40 We) were installed for experimental studies, providing necessary data for model validation and development of data driven models for engine performance monitoring.This paper reports the results of the project, concerning mapping the operational window for use of mixture of simulated biogas (50% methane, 50% CO2) and natural gas for each technology as an enabler of biogas utilization with natural gas as fallback solution. The CO2 reduction potential, when natural gas is replaced with biogas, is also presented. Moreover, the capability of using data driven models based on artificial neural network for online monitoring and control of the engine performance at various operational conditions is shown.Detailed reporting on various aspects of fuel composition and technology impact has been conducted earlier. This paper provides a total overview and a comparison of performance of the technologies tested in this study.Copyright

Techno-Economic Evaluation of an IGCC Power Plant With Carbon Capture

Most of the scenarios presented by different actors and organizations in the energy sector predict an increasing power demand in the coming years mainly due to the world’s population growth. Meanwhile, global warming is still one of the planet’s main concerns and carbon capture and sequestration is considered one of the key alternatives to mitigate greenhouse gas emissions. The integrated gasification combined cycle (IGCC) power plant is a coal-derived power production technology which facilitates the pre-combustion capture of CO2 emissions.After the establishment of the baseline configuration of the IGCC plant with CO2 capture (reported in GT2011-45701), a techno-economic evaluation of the whole IGCC system is presented in this paper. Based on publicly available literature, a database was established to evaluate the cost of electricity (COE) for the plant using relevant cost scaling factors for the existing sub-systems, cost index, and financial parameters (such as discount rate and inflation rate). Moreover, an economic comparison has been carried out between the baseline IGCC plant, a natural gas combined cycle (NGCC), and a supercritical pulverized coal (SCPC) plant.The calculation results confirm that an IGCC plant is 180% more expensive than the NGCC. The overall efficiency of the IGCC plant with CO2 capture is 35.7% (LHV basis), the total plant cost (TPC) is 3,786 US

Estimation of performance variation of future generation IGCC with coal quality and gasification process – Simulation results of EU H2-IGCC project

/kW, and the COE is 160 US

An EU initiative for future generation of IGCC power plants using hydrogen-rich syngas: Simulation results for the baseline configuration

/MWh.Copyright