Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - TURBO-REFLEX (TURBOmachinery REtrofits enabling FLEXible back-up capacity for the transition of the European energy system)

Teaser

The TURBO-REFLEX project aims to develop and optimise technologies that can be used to retrofit existing power plants as well as new machines in order to enable more flexible operation to provide the flexible back-up capacity needed for introducing a larger share of renewables...

Summary

The TURBO-REFLEX project aims to develop and optimise technologies that can be used to retrofit existing power plants as well as new machines in order to enable more flexible operation to provide the flexible back-up capacity needed for introducing a larger share of renewables in the EU energy system. The project mission of advancing current generation of fossil power plants translates into three ambitious key objectives:
OB1. Reduction of costs per cycle
TURBO-REFLEX will reduce the costs per cycle of a typical warm start in combined cycle plants from currently 50€/MW to ca. 35€/MW.
This will be accomplished by increasing part load efficiency, by improving the resistance to wear and damage prevention through advanced cooling schemes and transient component monitoring, and by data driven optimization of existing fleets with machine learning.
OB2. Increasing low load capability of existing plants
TURBO-REFLEX will reduce the number of hot starts required by 33% from currently approx. 150 per year to 100 by increasing the low load capability of existing plants. This enables operation at lower load levels for extended periods of time instead of going through wear intensive shut down/start-up cycles.
This will be accomplished by developing new, retrofittable technologies which increase the operability of compressor and combustor components within strict emission limits and active life assessment of highly loaded steam turbine components during low load operation.
OB3. Increasing load following capability
TURBO-REFLEX will double the load following capability of existing combined cycle plants from a ramp rate of currently approx. 6% per minute to 12% per minute. This improves the resilience of the electrical power system to maintain balance between consumption and generation also with an increasing share of fluctuating and non-dispatchable renewable sources.
This will be accomplished by increasing the flexibility of combustors, reducing the thermal gradients associated with fast load ramps through advanced cooling schemes, and by online monitoring and analytics to enable plant operation closer to actual physical limits.
The individual component technology improvements under TURBO-REFLEX for more flexible operation of thermal power plants can be summarized in three categories:
• Compressor off-design and operability
• Hot gas path technologies
• Mechanical integrity in flexible operation
These are complemented by online plant analytics & monitoring. Aimed at better understanding the plant behaviour as operated rather than as designed or manufactured, plant operators will be in a better position to optimize plant control and to trade flexibility with operating cost while limiting the impact on lifetime.
In order to verify the impact of the new technologies, whole plant performance assessments are carried out in parallel. Taking the view of the operator, a simulation package which was developed under the FLEXTURBINE project, is used to allow plants with the new flexibility characteristics developed by TURBO-REFLEX to virtually participate back-to-back against current state-of-the-art plants in a dispatch optimisation tool which simulates different European electricity markets. To this end, the assessment methodology developed under FLEXTURBINE is being further advanced to high-fidelity whole plant analytics and modelling, so as to better transfer component technology gains into market measures such as efficiency, flexibility and emissions.

Work performed

The TURBO-REFLEX project started with the optimisation of a prioritised set of technology areas and turbomachinery components:
• New compressor endwall designs suggest that desired increases in operational flexibility and part-load efficiency can be met. Further, numerical models of compressors were developed and validated and can now be used to optimize flow injections and extractions for better low load capability and faster ramp rates.
• A test facility of a combustor with enhanced load flexibility was built and measurements of the flow field conducted. Corresponding numerical models were created and calibrated against measurements.
• Additive manufacturing techniques were introduced to produce parts with advanced cooling schemes. Test rigs to characterise the performance of sample parts as well as scaled up versions were commissioned, and first test results were obtained.
• Accurate material data relevant to cyclic plant operation, such as burst and crack propagation tests, was generated. This enables the exploitation of stretched design limits under cyclic operation including light weight designs which have advantages under thermal cycling.
• Blade vibration tests were carried out with several steam turbine rotors. The results indicate considerable saving potential in ramp up times. The data will be used to feed an online life consumption tool which will enable visualization of residual lifetimes even from handheld devices such as smartphones or tablets.
• Condition based monitoring has proven beneficial to better understand the behaviour of plants as operated. Software development for a condition and efficiency monitoring system is underway. The application of machine learning algorithms to heterogeneous data sources shows promising results. A down selection of monitoring sensors tailored to flexibility limiting components was carried out and further development was initiated.
To support the evaluation of key technologies and their impact, the FLEXTURBINE assessment methodology was further developed and put into practice. Reference baseline plants were defined, and the results of the market simulation demonstrate good correlation to real plant data. Preliminary results show significant improvement in plant ramp rates associated with performance gains of the steam turbine.

Final results

TURBO-REFLEX brings together 26 partners from nine countries. Built around a core of nine European turbine industry OEMs and one power plant operator, the consortium also includes leading European universities and research institutes and highly specialized SMEs.
The project is in its first intermediate reporting period and therefore progress beyond the state of the art and expected impact is early to evaluate. Nonetheless, several achievements can already be claimed:
• Preliminary compressor endwall designs and air injections/extractions suggest that targeted flexibility improvements towards low load capability can be met.
• The feasibility of online monitoring of actual steam turbine life consumption has been demonstrated and implemented.
• Power generation analytics demonstrated the attractiveness of several steam turbine flexibilisation products targeting improvements in ramp rates and cycle costs.
• Economic assessment of technologies enabling faster ramp rates of steam turbines confirm significant positive impact on power plants participating in markets with a high penetration of renewable energies.
The results suggest significant progress towards the main three objectives: improving cycle costs, low load capability and ramp rates of combined cycle plants. In addition, the TURBO-REFLEX project impact will continue to be maximised by participation in relevant workshops and conferences and by providing public access to the plant performance simulation tool.

Website & more info

More info: https://www.turbo-reflex.eu/.