ccpp cycling.pdf

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June 08-10, 2010

PowerGen Europe

Fast Cycling and Grid Support

Capability of Combined Cycle

Power Plants to optimize the

Integration of Renewable

Generation into the European

Grid:Live examples from projects in

NL, F, UK, D

Lothar Balling

Gero MeineckeAndreas Pickard

Dr. Ulrich Tomschi

Siemens AG


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Contents

Summary .................................................................................................................................... 3

Introduction ................................................................................................................................ 4

The power generation market in a period of change.................................................................. 6

Fast Cycling Concept (FACY)................................................................................................... 8

Preserving warm start conditions ................................................................................... 9

Ready-for-operation mode of water/steam cycle ........................................................... 9

Optimized component design and plant operation to reduce material fatigue............... 9

Automation concept optimization ................................................................................ 10

Second-generation FACY – Start on the Fly ............................................................... 10

Recent Operating Results............................................................................................. 11

Grid Support............................................................................................................................. 12

Load Stabilization at low frequencies .......................................................................... 12

Primary and secondary frequency response ................................................................. 14

Island operation capability ........................................................................................... 15

Customer benefits..................................................................................................................... 17

Conclusion................................................................................................................................ 19

Copyright © Siemens AG 2010. All rights reserved. 2


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Summary

Combined-cycle power plants (CCPP) have a large share in today’s power generation in

Europe. The increasing contribution of CCPPs to power generation over the past decade can

be explained through their high efficiency, short execution time and relatively low investment

costs.

Meanwhile, regenerative and discontinuous power generation technology like wind power and

solar power is penetrating the market increasingly. Renewable resources certainly lead the

way to reduced CO2 emissions, but on the other hand their limited availability and

predictability pose a considerable challenge to grid stability. Periods of low generation due to

weather conditions (low winds, overcast weather, day and night conditions) have to be

covered by other types, like fossil-fired power plants. As a result, the requirements on

operational flexibility and rapid load response of the existing and new built fossil fleet, as

formulated in grid codes and customer specifications, are constantly increasing. These

developments drive modern power plant design to place a strong focus on operational

flexibility and grid support operation in order to allow a large renewable capacity to be

integrated into the grid systems.

Integration of modern technologies and rigorous optimization of the plant start-up process

have recently enabled Siemens to build most flexible and fastest-starting CCPPs in Europe,

e.g. in France, Netherlands and Germany. This is illustrated by examples presented in this

paper.

In the United Kingdom and similar markets the strict requirements of the grid code on

operational behavior in case of frequency deviations can be met by deploying a range of new

technologies. Island operation and part-load capability are being requested increasingly

throughout developed and emerging markets and these can be provided by introducingadditional and innovative plant control concepts.

Verification and validation of these capabilities was performed not only by theoretical

analysis, but also by live testing during plant operation. This means that the customer benefit

resulting from i.e. reduced fuel consumption and CO2- emissions during the start-up and

ramping process can already be realized in power plants today.

This paper describes the innovations in the area of plant flexibility and the results and

improvements achieved in examplary, recently commissioned combined-cycle power plants

in Europe.



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Introduction

Combined-cycle power plants are one of the more recent developments in the field of fossil-

fuel power generation. They achieved their current importance in the power generating sector

at the end of the 1980s. This is when power generation started to move away from the closed

monopolistic market structures of the time and towards today's competition-oriented markets.

The relatively low capital cost, high plant efficiency and short construction time are themain features that make this type of power plant interesting for new investments in a market

characterized by increasingly intense competition.

The first such plants quickly superseded existing older-vintage plants as a result of their

relatively low power generating costs. Initially they were used to meet base-load requirements.

Saturation of the electricity market and an increase in gas prices subsequently resulted in

increased deployment of combined-cycle power plants in the intermediate-load range, i.e.

plants were started up and shut down on a daily basis to cope with daytime peaks.

This new field of application first became apparent at the end of the 1990s in the U.S. and the

United Kingdom. The price of fuel continued to rise due to the large number of plants built

during the boom. Base-load plants which had already been planned were shifted to the load

regime of an intermediate-load plant.

The challenge presented to projects by this changed requirement gave birth to the idea of

trying to improve plant flexibility without compromising plant service life or plant efficiency.

As the market continued to develop, the demand for quicker startups soon followed the

demand for more frequent startups. This market demand finally resulted in the launch of a

development project (FACY – FAst CYcling) which combined all the initial engineering

ideas into a single integrated plant concept. The aim of the subsequently inititated R&D

program was to design a plant for an increased number of starts and to reduce startup times. If

possible, no limits were to be placed on the gas turbine by other power plant components,

such as the heat recovery steam generator or steam turbine, during a hot and warm starts.

In the course of the project, potential areas came to light in which further optimization could be achieved, although these had to wait for a second development generation to be

implemented. The major improvement offered by this second generation involved the startup

procedure. Hold points at which a plant waits until certain steam parameters have been

reached were eliminated as part of the shortened "Start on the Fly" startup procedure. The

steam turbine is now started up parallel to the gas turbine using the first steam which becomes

available after a hot start.

Whereas the first FACY generation reduced startup times for a hot start from 100 to 55

minutes, the second generation succeeded in pushing startup times down below the 40-minute

mark.

The first plants incorporating the advantages of both the first and second generations of theFACY concept are now being operated commercially. 30-minute startup times were recorded

e.g. at the 2x 430 MW F-class Single Shaft Sloe Centrale plant (NL) during acceptance tests

achieving more than 59% net efficiency. Equally good results have been exhibited by other

reference plants. This means that the expectations placed on the second generation of FACY

have been far surpassed in a number of cases.

Shortening startup times and improving the starting reliability while increasing the number of

starts was only one of many requirements with respect to plant flexibility. The ever increasing

percentage of renewable resources on the grid results in a certain destabilization due to

fluctuations in the availability of these resources. High-availability power plants, such as

combined-cycle plants, are required in order to compensate for these fluctuations. Therequirements with respect to grid support, which are usually defined in a grid code, have



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recently become more rigorous for these reasons. Some of the most stringent requirements are

to be found in the UK grid code. The topics

• Load stabilization at low frequencies

• Primary and secondary frequency response

• Island operation capability

have presented operators with a special challenge for quite some time. Siemens finally

demonstrated with the recently handed over 840 MW Multi-Shaft F-class power plant

Marchwood in UK that the problem could be solved by introducing additional technical

features and optimizing the plant concept without compromising maximum efficiency above

58%.

As with the development of FACY, a decisive success factor was the integrative approach,

which combined the potentials of several systems and components in a single solution. The

challenges were met based on the use of gas turbine compressor and firing reserves and fast

wet compression combined with an optimized I&C/ closed-loop control concept.



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7/20

2 208 10 2218164 146 12 240

Peak load:

Pumped Storage,

SCPP/Aero derivative/etc.

Intermediate load:

Predominantly CCPP

Renewables replace baseload units because ofmust feed-in obligations,but must be backed upfor wind/sun shortfall

Product Requirements:

• Low electricity production

costs

• Short startup times

• High starting reliability

• Good part load behavior

Regulation

load

DaytimeBase load:

Nuclear, Hydro Running

Water, Coal Steam Plants

Daily load profile (schematic)

E l e c t r i c i t y

p r o d u c t i o n

Figure 2: Daily load profile (schematic) and impact on CCPP

The new demand for extremely fast power generating availability is also becoming apparent

in our customer assessments. Whereas some customers made absolutely no assessment of

startup times only a few years ago, the assessment figures have increased in recent years in

some projects to over 100,000 €/min.



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Fast Cycling Concept (FACY)

As already mentioned, the idea of focusing plant design on an increased number of fast starts

originated from experienced market conditions and executed projects. A multidisciplinary

team of component and plant experts (for the steam turbine, gas turbine, balance of plant and

auxiliary systems, control technology (I&C) and steam generator) was formed around the year

2002 already to identify improvement potential in the existing plant concepts.

The team identified the following potential areas for improvement:

• Utilization of different technologies like stack damper, auxiliary steam etc. to maintainthe pressure and temperature in the main components during shutdowns

• “Ready-for-operation” mode of the water/steam cycle by a fully automated start upconcept without manual operation or intervention during hot start

• Optimized component design (e.g. high capacity and fast acting de-superheaters) and plant operation to reduce material fatigue caused by load cycling

• Flexible operation concept to allow the operator to predetermine component fatigueand to choose start up time and ramp rate

• Optimization of the automation and control concept

• New startup sequence "Start on the Fly" to allow a nearly unrestrained ramp-up

Figure 3 summarizes the main features of the FACY concept.

Figure 3: FACY features

All FACY features mentioned below help to reduce the startup time significantly. They are

modular and will be offered, configured and implemented on a project-specific base.



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Preserving warm start conditions

One of the focus components is the steam generator. Major heat loss occurs through the stack

and therefore a stack damper has been deployed to limit heat loss during shutdown. Cooling

down of the boiler is considerably reduced and delayed.

Furthermore, auxiliary steam can be used to heat the main heat-recovery steam generator

(HRSG). These measures clearly increase the maximum possible shutdown periods duringwhich criteria for hot and warm starts still apply.

Ready-for-operation mode of water/steam cycle

Auxiliary steam is also used to maintain the water/steam cycle in a ready-for-operation mode.

This means auxiliary steam is fed into the gland steam system of the steam turbine. Keeping

the gland steam system in operation prevents air from being drawn into the steam turbine and

the condenser. Since the steam turbine and the condenser are sealed off from the ambient air,

the condenser vacuum pumps can maintain the vacuum.

To enhance the startup procedure, the condensate polishing plant can be used to bring the

water/steam cycle within specified chemistry limits faster.

Optimized component design and plant operation to reduce material fatigue

The high-pressure drum of the HRSG is one of the most critical components involved in the

startup and ramping procedure. As a thick-walled component it is exposed to large

temperature gradients and high operating pressures. Thermal stress in the high-pressure drum

walls limits the load-, start up- and shut down- gradients of the HRSG.

The main feature of BENSON® boiler technology is once-through steam generation, which

means that conventional separation of steam and boiling water inside a boiler drum is not

necessary. Steam is generated directly within the evaporator tubes of the boiler, as shown in

Figure 4. There is no high-pressure drum in a BENSON®-type boiler, so these limits do not

apply. A temperature-controlled startup process which uses an optimized high-capacity de-superheater to limit steam temperatures during the startup process has been developed for

warm and cold starts. This reduces thermal stress in critical components of the steam turbine.

The application of BENSON HRSG allows to increase the number of permissable starts and

cycling events over the lifetime by reducing stress induced fatigue in the high pressure section

of the HRSG.

Figure 4: Drum-type HRSG vs. BENSON®-type HRSG



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Automation concept optimization

There are two approaches to optimizing the automation concept:

• Design limits are enhanced by the use of a closed-loop control instead of earlierempirical approaches. A turbine stress controller is used to determine thermal stress

based on temperature differences measured within the steam turbine and ensures thatstress limits are not exceeded. The turbine stress controller makes it possible to

shorten the startup time without reducing the lifetime of heat-critical turbine

components.

• Two additional startup modes – “FAST” and “COST- EFFECTIVE” – in addition tothe “NORMAL”- mode were introduced. The operator has the option of choosing the

appropriate startup mode depending on current electricity market prices and operating

and power supply requirements. Maintenance intervals can be extended using

the ”COST EFFECTIVE” setting and the “FAST” mode permits controlled fast

startup with consequently more frequent service activities.

The startup procedure is automated to a level that enables hot starts with only a few operator

actions, the aim being to minimize inefficient and unproductive periods during startup

preparations. Draining and venting are largely automated.

Second-generation FACY – Start on the Fly

In addition to the original FACY concept, a procedure for parallel startup of gas and steam

turbines has been developed. It is based on monitoring and controlling the temperature

gradients within limits acceptable for all critical plant components and the long term operation

experience with different steam conditions in our Siemens turbine design. The new concept

enables plant startups without any gas turbine load hold points. A new startup sequence wasimplemented for this reason – see Figure 5. The main innovation is the early steam turbine

starting point with earlier acceleration and loading of the turbine.

Figure 5: Improved startup through “Start on the Fly”



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Recent Operating Results

The above desribed features have been implemented across Europe and the second generation

has been showing excellent results in single shaft as well as in multi shaft configurations. As

examples the F-class single shaft plant in Pont sur Sambre (France) and the F-class multi shaft

configuration Irsching 5 (Germany) can be mentioned, as shown in Figures 6 and 7. Both

units have demonstrated their capability to start after a typical over night shut down to fullload in around 30 minutes.

In addition to their excellent dynamic capabilities both units have proven, that fuel efficiency

will not be compromised, since efficiency values above 58% and 59% respectively have been

achieved.

Figure 6: 430 MW Pont Sur Sambre

(SCC5- 4000F 1S)

27 min

It is noteworthy, that the Siemens single shaft operation concept allows a parallel start up of

all plant units individually, resulting in a multiple unit power output (e.g. x times 430 MW)

available in around 30 minutes, as it had been demonstrated in the above mentioned time

frame in the project Sloe Centrale (Netherlands) with 2 units.

Figure 7: 860 MW Irsching 5 (SCC5- 4000F MS)

Total Plant Load

GT1 Load

GT2 Load

Plant Start-u Time ~ 30

ST Load

~ 762 MW ~ 827 MW

GT1/2

ST



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Grid Support

In liberalized electricity markets, the minimum requirements with respect to the power

dynamics of power plants are defined in grid codes. Some of the most stringent requirements

imposed on plant dynamics are to be found in the UK grid code due to its island character.

Here we are focusing on three of the most critical dynamic properties:

• Load stabilization at low frequencies

• Primary and secondary frequency response

• Island operation capability

Load Stabilization at low frequencies

Normal fluctuations in the balance between generation and consumption are reflected in

fluctuations in grid frequency which can be compensated by means of regular frequency

control measures. The frequency can, however, also decrease or even increase more

significantly in the event of unusually serious and uncommon disturbances. Unfortunately the

decrease in grid frequency also means a reduction of speed and subsequently a decrease of power output. This decrease in speed causes the compressor in the gas turbine to transport a

reduced volumetric flow, thus decreasing gas turbine output if appropriate measures are not

implemented to compensate for this behavior which is due to physical reasons. The UK grid

code stipulates that the power output must be maintained for a minimum of 5 minutes down to

49.5 Hz so as to avoid further taxing of the grid due to under-frequency. If a greater decrease

in frequency occurs, the grid code permits a maximum decrease in output of 5 % at 47 Hz, as

illustrated in Figure 8

Figure 8: Load stabilization at low frequency in accordance with UK grid code

To counteract this decrease in power output, Siemens relies on several measures for increased

output which can be implemented at short notice. The decrease in output can be compensated

by rapidly opening the guide vanes on the compressor. The fuel flow is increased at the same

time. This can compensate for a drop in power of around 6 MW. In unfavorable operating

conditions this increase in output will not be sufficient on its own to meet the requirement

described above, however. In this case the Siemens patented fast wet compression concept

can be used to mobilize a further power reserve of around 12 MW. Demineralized water spray

is temporarily injected at the compressor inlet for this purpose. The mass of the injected water

increases the mass flow through the compressor. The evaporating water also cools the air flow

at the compressor inlet. The air density and consequently the mass flow through the



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compressor increase due to this cooling process. Rapid activation of the system constitutes a

challenge to control systems, as the increase in power output only takes effect at short notice

if the gas turbine control and the water injection are perfectly coordinated through the

optimized I&C system.

The implementation of these grid support features has been validated and demonstrated in theF-class multi shaft plant Marchwood (UK) at a power output of about 840 MW and >58%

efficiency (Fig. 9).

Figure 9: 840 MW Marchwood (SCC5-4000F MS)

The measurements from the Marchwood project in UK are illustrated in Figure 10. It can be

seen quite clearly that an 18 MW increase at each GT was achieved by opening the

compressor IGVs and then initiating fast wet compression, thus meeting the requirement ofthe UK grid code.

Figure 10: Load stabilization at low frequency test per GT (Marchwood)

CompressorTurn Up

Fast WetCompression

Simulated GridFrequency

6 MW byIGV Control

18 MW withFast wet

compression



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Primary and secondary frequency response

The purpose of load stabilization at low frequencies was to prevent further destabilization of

the grid when the frequency decreases due to major disturbances. Primary and secondary

frequency response are now required for grid support during normal operation. For this

purpose the UK grid code stipulates that a power plant operating at part load must be capable

of making additional power available on a temporary basis. Figure 11 illustrates therequirement of the UK grid code. We can see from the diagram that the power plant operating

at under 80 % load must be able to make available at least 10 % of its rated power within 10

seconds in the event of a decrease in frequency. For secondary frequency response 10 % of its

rated power must be made available within 30 seconds. As we can see from Figure 11, the

requirements are reduced in the event of loads over 80 %.

This figure also shows that the load must be reduced by 10 % of its rated power within 10

seconds as a high frequency response in the event of overfrequencies if the grid frequency

rises by 500 MHz. The island operation requirement is, however, even more stringent than

this criterion. For this reason high frequency response will not be discussed any further at this

point.

80% plant load,

primary frequency response,

increase by 10% / 10 s

Figure 11: Frequency response at low and high frequencies in accordance with UK grid code

Unlike load stabilization at low frequency, there is no need to look for a further power reserve

in this case. No new systems are required for this reason. The challenge lies more in the speed

at which the power must be made available.

To meet the requirements of the grid code, Siemens relies on fast repositioning of the

compressor IGVs on the one hand. On the other hand the fuel control has been optimized tosuch an extent that load ramps are possible without destabilizing combustion. Figure 12



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illustrates the results of the test in Marchwood and clearly shows that the required additional

power is achieved both after 10 seconds and after 30 seconds. In fact, the criterion is

significantly exceeded in both instances.

Figure 12: Frequency response test at low frequency (Marchwood, July 2009, data for one GT)

Simulated NetFrequency

45 MW in 10 sec

53.7 MW in 30 sec

PrimaryResponse

SecondaryRes onse

Island operation capability

In the preceding sections, the focus has mainly been on increasing power output. With island

operation capability the primary objective is to stabilize the island grid. In this case it may

happen that an excess of power in the island which has formed is suddenly faced with an

abrupt drop in consumption. The grid frequency increases very quickly as a result. The power

plant must react to this frequency increase by throttling power in order to stabilize the

frequency without causing a forced shutdown of the power plant due to over-frequency or any

other uncontrolled process. Uncontrolled shutdown of power plants can result in a grid

collapse.

This is why the UK grid code stipulates that the power plant must be capable of decreasing

from rated power as a worst case scenario to the design minimum operating level (DMOL).

The DMOL must not be smaller than 55 % of rated power in this case. This load reduction

must be effected so quickly that the island frequency remains below 52 Hz. Grid studies based

on the UK National Grid requirements show that the load reduction must take place within

around 8 seconds.

The power plant must detect island formation of this kind automatically and take immediate

action. As soon as island operating mode is activated, permitted load change ramps are set to

the maximum value. The inlet guide vanes in the gas turbine compressor are closed without

delay. At the same time the different closed-loop controls ensure that the power is decreased

at the maximum rate of change for load. The flame stability and potential flash backs in the



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combustion system is the main objective of closed-loop control optimization so as to avoid

emergency shutdown of the gas turbine.

As we can see from Figure 13, the gas turbine output was decreased by 52 % within 4 seconds

as the result of a simulated fast frequency increase of 0.9 Hz during the Marchwood test

without initiating a plant trip. A further decrease of 4 % was achieved in the following 4

seconds, thus also more than meeting the second grid code requirement.

Simulated GridFrequency

Power Out ut

Figure 13: Island operating test at Marchwood with one GT

Meanwhile these basic plant features demonstrated in F-class plants are being transferred also to H-

class technology and have already been validated in open cycle operation at Irsching 4 (Germany)

last year (Figure 14), demonstrating that even this latest and highest efficient technology is capable

of supporting the same stringend grid code requirements.

Figure 14: Grid code test at Irsching 4 (SSC5-8000H) in open cycle mode



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Customer benefits

The previous sections clearly demonstrate that FACY and Start on the Fly permit a reduction

of startup times as well as operating modes with an increased number of startups. These

features optimize the cycling regime of a plant.

An operating regime which permits a larger number of startups and thus enables nightly

power plant shutdowns offers two additional benefits:

• CO2 emissions are minimized by shortening inefficient plant startup times thanks to anoptimized startup procedure. Maximum electrical efficiency is reached faster and total

emissions are reduced.

• Since nightly shutdowns and reliable startups become economically feasible, overallCO2 emissions are further reduced as inefficient overnight parking at part load is

avoided. Other power plants within the grid can then be operated at full load and

maximum efficiency.

Customers benefit from this, primarily through fuel savings and a reduction in CO2 emissionsduring the startup phase. Shortening the startup time by using Start on the Fly for a hot start

offers an estimated added value of more than 3 million euros alone, assuming that the savings

described above are realized over the service life of a 430 MW power plant. The option of

disconnecting the plant from the grid overnight offers enormous potential in the form of

savings in operating costs.

Night-time electricity prices are at such a low level in Europe that a combined-cycle power

plant can no longer be operated at a profit during the night due to high gas and CO2 costs (see

Figure 15). In order to minimize these losses, power plants are operated at part load or are

shut down altogether at night.

60

Electricity Price EEX 13.01.2010

& CO2 Costs at Full Load Gas

20 22 16 1814121086 2 4 0

50

40

0

30

20

24

Figure 15: Typical electricity price curve (€/MWh) compared with gas and CO2 costs (example

from January 13, 2010, European Energy Exchange)

Reducing the load already brings about a significant reduction in losses. However when the

load decreases, so does overall efficiency, meaning that gas and CO2 costs can only bereduced disproportionately.



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In addition to the positive effect of load reduction, shutting a power plant down at night can

achieve other important improvements. Only shutdown and startup costs are incurred by this

method. Restrictions relating to the permitted number of startups for the plant have been

significantly improved with the FACY program. FACY and Start on the Fly have also

significantly reduced startup times. The result is lower gas consumption and lower CO2

emissions, providing the power plant operator with an additional economic benefit for everystart.

Figure 16 shows the CO2 and fuel savings which can be achieved by night-time shutdown

using FACY compared with night-time part-load operation at about 25 %. We can see from

the graphics that the power plant in the example can avoid up to 130 tons of gas consumption

and 362 tons of CO2 emissions per night through night-time shutdown. This increases annual

power plant profit by 4.8 million euros as compared with night-time part-load operation.

Figure 16: Savings of gas and CO2 emissions resulting from night-time shutdown

The calculation example illustrated in Figure 16 is based on a gas price of 20.2 €/MWh, CO2

costs of 2.88 €/MWh and a night-time electricity price of 29.4 €/MWh. The performance data

are based on an SCC5-4000F single-shaft with a cooling tower.

Today grid support features are primarily specified by the grid access requirements of theindividual countries. No monetary valuation of the additional plant flexibility is included in

tender specifications as yet. For this reason today's plants are designed purely based on grid

code specifications. Depending on the level of electricity market liberalization, the different

flexibility features allow to generate additional earnings, first of all by participating in the

frequency reserve market. Furthermore, plants with high reliability and operational flexibility

regarding their behavior under disturbed grid conditions are expected to be prioritized for

dispatch.

-130 t

Shut down &

Start on the Fly

43

Part

Load

173

-362 t

Shut down &

Start on the

Fly

118

Part

Load

480

-4,8Mio€

Shut down &

Start on the Fly

1,3

Part

Load

6,1

Reduction of gas consumption and CO2 emissions [per night] Economic impact [per year]

Gas Consumption [in t] CO2

Emission [in t]Cost for operation/ shut down

and start up [in million €]

Based on 200 starts p.a.



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Conclusion

Siemens, as an original equipment manufacturer and turnkey power plant provider, has

successfully implemented a new plant feature called FACY to enable highest operational

flexibility with fast startup times and an increased possible number of reliable starts.

FACY is a fully integrated plant concept, which comprises optimizations of turbine design,

heat recovery steam generator, water steam cycle, startup sequence and automation concept.

One of the advanced FACY features is the implementation of a stress controller to enable the

plant operator to choose between fast, normal and cost-effective startup modes, corresponding

service intervalls and life time consumption.

In the light of these preconditions and the high startup reliability of combined-cycle power

plants, daily shutdown and startup with FACY is the most economical solution to reduce the

impact of nightly losses. This maximized operational flexiblity in combination with highest

efficiency over 59% with our SCC5-4000F plant concepts ensures a higher dispatch rate

compared to conventional power plants.

FACY also significantly increases plant startup efficiency and in combination with a nightly

shutdown mode this clearly reduces CO2 emmissions and increases overall power plant

profitability.

In addition to the optimization of startup procedures and an increase in the number of

permitted starts, Siemens offers a plant design which can even meet very stringent grid

requirements, e.g. in the UK. This is only possible if the plant is designed using an integrative

approach. Closed-loop controls allow the plant potentials to be utilized to the full. A fast wet

compression system is activated to maintain power output in the event of low grid frequency.The Marchwood plant has demonstrated that all the strict UK grid code requirements with

respect to plant flexibility are fulfilled in addition to its top efficiency at more than 58%. The

proven concepts and technologies are now ready for transfer to future F-class and H-class

CCPP projects to support increasing operational flexibility and grid support requirements.

The newly introduced features and concepts help to secure reliable power supply and grid

stability and enable the fast growing market penetration of discontinuous renewable power

generation to further reduce CO2 emissions in Europe.



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Disclaimer

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