MW Combined Cycle Gas Turbine Research Articles

Process synthesis for amine-based CO2 capture from combined cycle gas turbine power plant

The study provides technoeconomic evaluations of advanced MEA-based Post-Combustion CO2 Capture (PCCC) process configurations applied to a 750 MW Combined Cycle Gas Turbine (CCGT) power plant. Rigorous rate-based model of the PCCC process developed in Aspen Plus was validated and then used to study synergistic effects of combining three process configurations in one flowsheet using energy and levelized cost of capture as key performance indicators (KPIs). The results of the energy and economic analysis elucidate that Absorber Inter Cooling (AIC) + Rich Solvent Split (RSS) + Lean Vapor Compression (LVC) is the optimal combination of MEA-based PCCC process as it provided minimum regeneration energy (2.80 GJ/tCO2) and levelized capture cost (72.7 $/tCO2) representing an overall energy and cost savings of 6.25% and 8.95%, respectively. The study demonstrates that the usage of single KPI such as energy savings can provide misleading results. For example, combination of AIC + RSS + Inter Heated Stripper (IHS) provided maximum equivalent energy savings (3.50%), however, it did not result in highest cost savings due to high capital and operating costs of additional heater and pump. Overall, the study underlines the potential of advanced mature technologies on energy and cost reductions.

Combined-cycle gas turbine power plant integration with cascaded latent heat thermal storage for fast dynamic responses

The combined-cycle gas turbine (CCGT) power plants are often required to provide the essential fast grid balance service between the load demand and power supply with the increase of the intermittent power generation from renewable energy sources. It is extremely challenging to ensure CCGT power plants operating flexibly and also maintaining its efficiency at the same time. This paper presents the feasibility study of a CCGT power plant combined with the cascaded latent heat storage (CLHS) for plant flexible operation. A 420 MW CCGT power plant and a CLHS dynamic models are developed in Aspen Plus based on a novel modelling approach. The plant start-up processes are studied, and large amount of thermal energy can be accumulated by CLHS during the start-up. For load-following operation, extensive dynamic simulation study is conducted and the simulation results show that the extracted exhaust gas can be used for thermal energy storage charging, and the stored heat can be discharged to produce high temperature and high pressure steam fed to the steam turbine. Besides, the stored heat can also be used to maintain the heat recovery steam generator (HRSG) under warm condition to reduce plant restart-up time. The simulation results demonstrate that the integration of CLHS with CCGT power plant is feasible during the start-up, load-following and standstill operations.

Off-design point modelling of a 420 MW CCGT power plant integrated with an amine-based post-combustion CO2 capture and compression process

The use of natural gas for power generation is becoming increasingly important in many regions in the world. Given that the combined cycle gas turbine (CCGT) power stations are lower in capital cost and carbon intensity than their coal-fired counterparts, natural gas fired power stations are considered a vital part of the transition to a low carbon economy. However, CCGTs are not themselves “low carbon” and in order to reach a carbon intensity of less than 50kgCO2/MWh, it will be necessary to decarbonise them via CCS, with post-combustion CCS currently regarded as being a promising technology for this application. In this study, we present a detailed model of a 420MW triple-pressure reheat CCGT and evaluate its technical and economic performance under full and part load conditions. We evaluate the technical performance of our CCGT model by comparison to an equivalent model implemented in Thermoflow THERMOFLEX and observe agreement of power output and efficiency to within 4.1% and the temperature profile within the HRSG within 2.9%. We further integrate the CCGT with a dynamic model of an amine based CCS process, and observe a reduction in the base plant efficiency from 51.84% at full-load and 50.23% at 60% load by 8.64% points at full-load and 7.93% points at 60% load. A core conclusion of this paper is that CCGT power plants equipped with post-combustion CCS technologies are well suited to dynamic operation, as might be required in an energy system characterised by high penetrations of intermittent renewable power generation.

Dynamic behaviour analysis of a three pressure level heat recovery steam generator during transient operation

The context of the deregulated energy market and the rapid expansion of the non-predictable energy sources, are stressing the necessity of improving the flexibility of traditional power plants. Cyclic operation guarantees high profits in the short term but causes a lifetime reduction due to thermo-mechanical fatigue, creep and corrosion. In this context, combined cycle gas turbine power plants are the most concerned in flexible operation. However, the most stressed devices are in the Heat Recovery Steam Generator. For these reasons, in the present work, a procedure able to estimate the most stressed devices lifetime reduction is proposed. The core of the procedure is the power plant dynamic model. The selected test case is a 380 MW combined cycle gas turbine power plant composed by a gas turbine and a three pressure level Heat Recovery Steam Generator with reheat. The model's peculiarity is the full implementation of the components geometry. The model is able to predict the plant steady-state, part-load and dynamic behaviour. Different transient conditions are tested and the superheater lifetime reduction computed. Results show that the procedure can be considered as valuable innovative instrument to assist power plant designers and operators in order to improve the plant's flexibility.

The impact of variable demand upon the performance of a combined cycle gas turbine (CCGT) power plant

This paper presents experimentally measured data showing the impact of variable demand on a modern 800 MW CCGT plant. The results contrasting the performance of the plant when operating under optimum conditions with those measured when modulating the output to match dispatch instructions is presented and compared. These contrasts include the impact of step changes, continual modulation and both hot and cold starts of the plant. The results indicate the changes in fuel used per MWh, CO 2 emitted per MWh and the NOx emissions under different operating modes. From the subsequent analysis significant increases were recorded in both fuel used and CO 2 emitted when the plant departs from optimum operating conditions. When the plant is requested to cease generating due to over capacity on the system, major increases in the emissions of NOx, when required to restart generation together with large increases in the fuel used and CO 2 emitted per MWh, can be observed.

Hungary-Ukraine Energy Cooperation and Its Contribution to the Security of Supply in the European Union

The European Union (EU) is expected to be increasingly dependent upon non-EU primary energy resources as domestic resources are depleted. Ukraine is the largest country in the world by the volume of gas transit: Annually through the Ukrainian gas pipeline the transit gas deliveries amount to 140 billion m3 including 120 billion m3 to countries of Central and Western Europe. Ukraine also has an underutilized 750 kV transmission line that reaches into the heart of the neighbouring EU member Hungary. This high-level natural gas transportation infrastructure and the existence of major electricity transmission lines results in Eastern Hungary being a key location for a 2,400MW Combined Cycle Gas Turbine (CCGT) plant. A large CCGT power plant usinig the best available technology in this region would not only benefit from existing infrastructure but also provide electricity for the Central and Eastern European (CEE) region, and may supply the impetus for major regional development initiatives.(1)

The 900 MW Combined Cycle Gas Turbine Power Station Project at Killingholme

PowerGen's 900 MW combined cycle gas turbine (CCGT) power station at Killingholme achieved full load output over two months before the scheduled date for full commercial load and less than 34 months after the turnkey contract was placed. This paper reviews the development of PowerGen's first CCGT power station, discusses the reasons for the choice of this type of plant and examines early operating experience. The contract strategy, a technical description of the plant, the project programme and the environmental impact of the plant relative to a conventional coal-fired power station are also included.