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Gas &Steam

Turbine

The magazine for the international power industry April 2016

www.PowerEngineeringInt.com

Special Focus

THE DANGERS OF GASTURBINE MULTI-STARTS

STEAM TURBINES: NEWTRENDS & INNOVATION

DRY AIR INJECTION TORAISE FUEL EFFICIENCY

HOW TO PICK THE BESTFILTRATION SYSTEM
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A new generation is born

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POWER ENGINEERING INTERNATIONAL

Contents

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Power Engineering InternationalApril 2016

Get the latest gas and steam turbine specifications from the OEMs: p22

Credit: Siemens48 Ad Index

On the cover

Cover design: Samantha Heasmer. Images courtesy of Ansaldo, GE and Siemens.

APRIL 2016///VOLUME 24///ISSUE 4

Features

2 Advances in steam turbine technology

Central to the future of thermal power plants is the steamturbine, and its manufacturers are focussing on improving

the design and performance of these machines.

10 The risk of start-stops to gas turbines

The increasing requirement for gas turbine multi-starts couldseriously injure your assets.

12 Boosting gas turbines with dry air injection

A demonstration project in Saudi Arabia has installed a dry

air injection system upgrade to improve fuel efficiency.

18 The cost of ineffective filtration

What filtration factors need to be considered to optimizeturbine efficiency and reduce maintenance frequency.

Gas & Steam Turbine Directory

22 Gas & Steam Turbine Technical Specifications

33 Products and Services Listings

38 Company Listings

Coming up in Mays issue

POWER-GEN Europe issue

Optimizing gas engine performance

Emissions control: meeting new European regulations

Piping and the European Pressure Equipment Directive

The way forward for energy storage

Are SMRs the future of nuclear in Europe?

Solar power in the Russian Federation

Inside two new cutting-edge gas-fired plantsPOWER-GEN Europe preview and highlights
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4/522 Power Engineering InternationalApril 2016 www.PowerEngineeringInt.com

Steam turbines

Advancing steamturbine technology

David Appleyard looks at how steam turbine manufacturers are focusing onimproving the design and performance of their machines.

Renewables may have struck a

decisive lead in new worldwide

power capacity investment, but

King Coal is still to be dethroned.

Indeed, according to GE, coal

still represents nearly 30 per cent

of global energy consumption its highest

share since 1970 and provides 40 per cent

of the worlds electricity. While this number is

expected to fall, coal will remain the backbone

of the power system in many countries.

Consequently, the global steam turbine

market is projected by some analysts to growfrom an estimated $12,872.5 million in 2015 to

some $19,292 million by 2020.

Trevor Bailey, General Manager of Steam

Power Systems at GE, comments: Coal is still

around and will be around for some time

in certain parts of the world where its the

most readily available fuel. We need to find

responsible, environmentally friendly ways of

using that fuel.

With the drive to improve environmental

performance across the power

generation sector, manufacturers of key

electromechanical equipment are under

pressure to improve energy efficiency, but

in a competitive market operations and

maintenance considerations are always high

on the agenda. In the case of coal-fired or

other thermal plant, the steam turbine is one

principal area of focus for the major OEMs.

Predicting operational integrity

Jiri Fiala, Director of R&D at Doosan Skoda

based in the Czech Republic, emphasizes the

role of detailed knowledge of a steam turbine

in improving plant performance: First, what is

important for the operator? It is important to

have a good picture of the turbine cycle. It

means information and this is measurementconnected with the control system. On the

other hand, we can offer a remote monitoring

system which means that we are always

connected online and we are able also to

advise the plant operator.

Fiala explains how such a system can

support plant operations: We are asked by

our clients that their turbines should be able to

operate without a major overhaul for maybe

ten years or eight years. Our answer is yes, but

it is necessary also to take into account the

correct operation of the turbine. For example,

the purity of the steam as mechanical

impurities can damage some surfaces of th=e

flow path can damage some glands and

seals. If the chemical purity of the steam is poor,

there can also be wear on the rotor blades

which can be, after some time, damaged by

chemical effects on the material.

We are able to extend the period

between service intervals, but it is necessary

for the operator to comply with some

recommendations to keep the purity of the

steam within some limits.

This is a point picked up by Bailey: Theres

an element of erosion from the continuous

flow of steam through the steam turbine that,

over many years, does have some impact,particularly on the longer blades. The last

stage or the low pressure section of the

turbine, for example, can experience some

heavy erosion.

Theres also a mechanical integrity

element to this, making sure the rotating

equipment is operating safely and that it is

capable of operating over extended periods

of time, as many power plants are operating

way beyond their original design life.

Making life assessment studies and

making sure the equipment is safe to operate

is another part of the service portfolio.

He continues: Having that deep domain

knowledge around how the machine is

Steam turbines are central to the future of thermal power plant

Credit: Siemens
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Steam turbines

designed, how the materials are incorporated

in the different parts of the rotating equipment,

and being able to apply that to predict

what remains of the in-service life of a piece

of equipment is a core competency and

obviously we use that extensively.

Were constantly, through our monitoring

centres, gathering data and understanding

trends on different fleets so we can start

to predict failures on families of machines

and therefore make that less traumatic for

customers, because we can step in and

advise them of the high probability of a failure

in this operating mode.

Predictive maintenance is a very

important dimension, especially on

equipment thats running. Its got a design

life of 30+ years and could be running longer

than that, and as we move more into the

industrial digital environment were able to use

digital applications to help customers operate

their plant more efficiently, preventing forced

outages by having more innovative, predictive

maintenance and monitoring approaches.

Dr Lutz Voelker, responsible for the Research

and Development of Industrial Steam Turbines

at Siemens, also emphasizes the importanceof long-term predictability: Material is one

of the key elements in the design and it is

important to know its behaviour after ten, 15,

25 years of operation.

If you have a better understanding of the

long-term behaviour of the material, you can

apply this knowledge to the design philosophy.

So if you have, in the past, used very heavy

construction due to uncertainties in the long-

term behaviour, now with new knowledge of

the materials behaviour you can optimize

the design by wall thicknesses and main

dimensions reduction, keeping same safety

margins, as you know exactly what will happen

after 20 or 25 years of operation.

We can, for example, improve the design

philosophy, make the turbine lighter in total

weight, and extend the application range

and operational behaviour of the technology.

Voelker adds: To improve operational

availability further, Siemens offers a remote

monitoring system which allows tracking

of some key values of the turbine. Based

on knowledge over its lifetime, customers

can get direct feedback as to whether the

defined turbine overhauls are required or if the

operation can be extended.

Changing operational profiles

Noting the changing demand profile for

thermal plant operation in many markets as a

result of increasing volumes of variable output

renewables, Voelker highlights another trend

in steam turbine development: Flexibility and

customization. That means fast startup times

or unlimited load changes while in operation

to act on and support stronger green power

generation. Steam units are not making base

load as in the past. Further, steam turbines

used in combination with green power

generation such as solar plants must fulfil the

special demands of this application. To bestill successful with steam turbines, we have

to follow these new market requirements for

operation.

Fiala also notes the changing marketplace:

Demands to improve partial load operation

or fluctuations in demand have risen in recent

years, for example in Europe where there

are increasing volumes of variable-output

renewable energy such as photovoltaics.

Equipment connected to the inlet parts

of the turbine will enable higher power output

and also very high efficiency on lower power

operation, very good dynamic efficiency.

Increasing ramp-up rates and shortening

startup procedures or startup times, for

example increasing the number of starts,

is a typical request from, for example, solar

power plants which every day start and

stop the turbines. This requires changes andmodifications to the design, mainly on the

rotor part to reduce concentration of the

stresses on the rotor, to enable the rotor to start

very rapidly if the number of starts and stops

for the application is very, very high.

It is possible to do this, but with some

special design provisions. Measuring the

temperature close to rotor or some stator parts,

and using some evaluation in the control

system, you can calculate the temperature

on the surfaces of the turbine and inside

the rotor. Based on this knowledge, you can

change or evaluate the startup procedure to

maintain limits within a safe area. Above this

limit, definitely the lifetime of the material will

expire very fast.

He adds: On the other hand, the control

system can take all this information and

evaluate, lets say, a residual lifetime of the

rotor.

Voelker: It is an improvement based on the

latest developments in the flow path of the

design.

Sealing and steam pathIn addition to improving predictability in

various operational modes, improvements

also cover the various sealing systems within

the machine and steam path to boost thermal

efficiency for example, the introduction of

abradable materials for the sealing concept

or brush steel technologies to improve the

efficiency and the internal performance.

As Ronald Schmidt, responsible for the

industrial steam turbines business segment

at Siemens, explains: We had a very robust

blading path design in the past. It wasefficient but not as good compared to what

we saw in the big steam units, but for different

applications we have now introduced highly

sophisticated blade path designs which are

normally used for the big steam units, and

in the 3DV blading which is a lean sweep

blade path design with an improved sealing

geometry that means more sealing strips per

blade row to cover or reduce the leakages.

Applying expertise derived from other

areas of business is also a key consideration for

GE, as Bailey observes: GE acquired Alstoms

power generation and grid businesses late

last year, and one area where we do have

significant overlap is around steam turbine

Detailed knowledge of a steam turbine can improve plant performance

Credit: Doosan Skoda Power

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technology. Thats actually provided us

with the opportunity to look at two ways of

addressing how best to provide the most

efficient steam turbines to make best use of all

these fuels, and we are now actively looking at

the technologies that are available to us.

GE has historically been a wheel-and-

diaphragm-type architecture, more an

impulse steam turbine, although in recent

years with HEAT (High Efficiency Advanced

Technology), primarily used in combined

cycles, the firm has moved more into high

reaction-type architectures. Alstom has a mix

of technologies coming from both camps.

And, as Bailey notes, one area of

development is in the area of sealing within

the steam turbine: We have a mix of sealing

technology thats applied to different places

on the steam turbine: brush seals, traditional

labyrinth seals, abradable-type seals. With the

combination of Alstom and GE technologies,

we now have a broad range of sealing

capability that can be used across all of these

applications, and that can vary depending

on the mission that the

steam turbine has to

operate within.

If youre in

combined cycle

where the machine

may be operating for

prolonged periods

at part load or could

be stopping and

starting every day, the

sealing technologies

can be different to a

machine like a nuclear

application where itsmore a baseload-type

application.

Bailey concludes:

From a GE point of

view, a lot of sealing

technology for rotating

equipment has flowed

down from our aviation

and gas turbine

capabilities and is

now being applied in

a steam environment.

Alstom obviously

comes at that from

a different direction,

looking at it from a steam turbine point of

view from the outset. Were going through that

process of learning from each other and being

able to draw upon the best technologies andlooking at the operating experiences from

both companies. I think there are going to be

some exciting developments as our engineers

really get to grips with what we now have

available to us.

Improving steam condition

One well-known route to improving the thermal

efficiency of power plant systems is to boost

the temperature and pressure characteristics

of the steam.

Bailey says: Operating steam temperatures

we continue to push. Were operating at

600C live steam inlet conditions, pushing re-

heat temperatures further, and that means

materials development continues, obviously

pushing 650C inlet temperature and longer-

term to 700C, potentially beyond that even.

A number of programmes are in place

to drive materials development, which

GE is actively engaged in, along with the

production techniques required.

Its not something that will change

dramatically, its a more evolutionary process.

From a steam turbine point of view its not such

a big challenge; other components such as

boilers and some of the interconnecting

pipe work actually are somewhat more

challenging from a materials point of view. We

could move to higher temperatures now with

a steam turbine, but youve got to bring the

rest of the power plant with it.

Nonetheless, GE has revealed a

breakthrough in re-heat technology.

An area that is of interest to us is around

double re-heat technology. In the past, large

coal power generation has been based ona single re-heat Rankine cycle. Were looking

at technologies now where we can take two

re-heat cycles back to the boiler and pass it

through a second intermediate turbine, which

gives us a significant efficiency boost, says

Bailey.

Were pushing the materials capability

that we have available to us too. Were using

proven technology with a slightly different

steam cycle. It delivers a significant boost

in cycle efficiency in excess of 1 per cent in

overall net power plant efficiency. Were calling

it LE2 Leading Efficiency, Lower Emissions as

clean-as-it-can-be power generation using

solid fossil fuels.

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Steam turbines

The double re-heat cycle follows on from

the operating experience of the worlds most

efficient single re-heat power plant at the RDK8

installation in Germany. GE says the plant atthe Rheinhafen-Dampfkraftwerk facility in

Karlsruhe has achieved 47.5 per cent net

thermal efficiency while producing 912 MWe.

If you looked at a double re-heat in the

same location as RDK8, it would be in the

range of 49.5 per cent plus net power plant

efficiency, says Bailey.

Doosans Fiala also picks up on the push

towards 700C steam. We have in operation

ultra-supercritical turbines which operate at

about 600C. High steam parameters mean

high efficiency and 600C is fairly typical. On

the other hand, many companies, including us,

are thinking about 700C. For 700C conditions

we have prepared some materials for the rotor,

components welded from several parts. We

have done some tests on this welding process

and are developing some components for this

700C plant, which we suppose is the future.

Of course, that will depend on the cost or the

price of the electricity because everything

should be calculated economically, and

higher parameters also mean higher cost or

higher investment, so everything should have

sufficient payback.

There are supply chain considerations too,as Fiala says: 600C conditions are common

in the market so that is why, for example,

P92 material for the casting or hot casting

or main pipelines is available. On the other

hand, when we speak about 700C then it is

necessary to speak about alternatives such as

nymonic alloy or chromium alloy combination

of the rotor. This is not an easy task and that is

why, over the last two, two and a half years we

have developed such a welding procedure. It

does also depend on the supplier because

we can develop some welding procedures

or heat treatment procedures but we need to

buy good quality forgings.

Siemens is also extending turbine steam

conditions for industrial steam turbines: With

the enhanced platform, we have increased

the lasting capability for our building block

system, which now goes up to a maximum of

565C, 180 bar pressure level for continuous

operation. Compared to the former design,

that is an improvement of 25 Kelvin higher

temperature and roughly 40 bar higher

pressure level, says Voelker.

He adds: For the area of industrial units

we are not considering actual 700C steamconditions. The industry is currently focussed

in the area of 560C580C as we see no

benefit in improving or increasing live steam

conditions on industrial units. If you are talking

about higher live steam conditions, then it

goes more in the direction of the big steam

and CCPP units. Big steam is at the level

of 600C, 280 bar and CCPP at the level of

600C, 177 bar that we already have in the

field. Especially for CCPP, Siemens is working to

increase the live steam conditions further.

New manufacturing techniques

One further trend concerns the use of novel

manufacturing technologies to reduce lead

time and costs.

Schmidt says: I believe what is next on

the operations side of manufacturing is the

full digitalization chain, which we are working

on. Obviously R&D gives us a very flexible

product with lots of alterations possible for the

specific customer order. Unfortunately, from a

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manufacturing perspective, the one-off which

this creates in terms of manufacturing is the

challenge we have to manage.

We believe the digitization initiative we

are running there will give us a little bit of

an edge as well. The concept really is that

when R&D designs, lets take a casing as an

example, they provide their particular design;

this is altered to the customer-specific order in

our customer order engineering team, and

then this creates a 3D model, which is then

submitted to the supplier which casts the part.

The difficult portion is really that we

need to know the as-is dimensions for the

next manufacturing step. The vendor, in this

case the casting house, provides the as-is model and this is then submitted to the

manufacturing team in Goerlitz, and while

the transportation is being done from China

or wherever the vendor is located, we can

prepare manufacturing of the part already

with the as-is dimensions of the scanned

part we received from the supply base. Then

we can optimize manufacturing technology

with the blades. In the end we simulate the

manufacturing of the part, so when the actual

part arrives in the plant we can immediately

start machining without spending a lot of time

on setup.

We will have an optimized programming of

the machine, and the results are documented

electronically as well. So if we go to a unit that

is running in the field, we know immediately

what the dimensions are because we have

the electronic models, and then we can

service the unit much better going forward.

Its the 3D model of the components, the

simulation of the process and the machine

tool itself, these three

things need to be

brought together,

really, to do this in a

concurrent way rather

than sequential.

Schmidt also

notes the use of

laser sintering in

the manufacture of

components from the

gas turbine arena: We

do use 3D printing,

but for various gas

turbine components.For steam turbines we

utilize this technology

rather in the area of

machining fixtures. We

need very variable

parts so the fixtures

need to be variable as

well, and if you do that

in metal all the time it

is very costly and takes

quite a long time. Now

you do the stimulation

of the part, then you

print the insert for the

machining fixture. This

is a specific example where 3D printing helps

to save costs and gain time.

He concludes, though: In the steam

turbine unit, laser sintering doesnt seem to bethat attractive at the present moment, first and

foremost because of cost.

The cost issue is also noted by Fiala: Of

course there could be a use of some different

up-to-date technology for some components,

such as laser sintering, but definitely I think,

for example, gas turbines which use higher

temperatures are a different story. Steam

turbines are more or less conservative:

definitely we use some special materials, but

typically smaller rather than big components

I mean, for example, some sealing parts

because new techniques or technologies

usually are also more costly, so that is why we

need to evaluate the cost of the material and

manufacturing.

In the future, for example, there will be some

3-D printing mainly for small components, but

maybe not always for small components.

He adds: There are also some standard

procedures with some scope for improvement

of the surface, for example hardening of the

inlet stages of the last or last-but-one stages,

which operate in wet steam to improve erosion

protection.

Future turbine developments

Looking ahead, Voelker suggests further

improvements in performance are anticipated:

What we are working on currently is, of course,

some further improvements in efficiency, and

strong interest and activity in the field of further

development in the last stage blading area.

That is one key component in the overall steam

unit, to reach higher performance levels.

In mid-2015 Siemens also delivered a steam

turbine that operates almost entirely withoutlubricants, with the bearing systems consisting

of air-cooled, active electromagnetic bearings.

The first 10 MW turbine equipped with

magnetic bearings was installed at Vattenfalls

lignite-fired Jnschwalde steam power plant

in the German state of Brandenburg.

Voelker concludes:We believe that flexibility,

going forward, is key in both dimensions: cost

and efficiency. That needs to be supported as

well by a flexible manufacturing system.

David Appleyard is a freelance journalist

Visit www.PowerEngineeringInt.com

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12/5210 www.PowerEngineeringInt.comPower Engineering InternationalApril 2016

Gas turbine maintenance

The growing need for multi-starts could seriously injure your assets, says Gary Lock

A

s the energy industry

increases its uptake of

power from renewables,

the level of demand on

large frame gas turbines

becomes less predictable,

with start-ups triggered by the vagaries of the

weather and the economic market.

Gas turbine operators are having to multi-

start machines, sometimes as often as twice

a day. Indeed, multi-starting has become

the norm it is common to hear of over 500

starts a year with superfast ramp-up periods.

What damage is this causing to machines

that were designed, effectively, for continuous

operation? And what might be the resulting

risks and cost implications for the industry?

Gas turbines were initially designed tofacilitate base loading with minimal starts but

with industry changes, multi-starting is putting

high-integrity components through multiple

strain cycles for which they were not designed.

Making assumptions that components can

withstand these requirements based on

the generalization that a defined number of

starts is equivalent to a particular number of

operating hours is at best optimistic, and at

worst could be dangerous.

A key change in the impact on

components is that, in traditional use, the

dominant failure process for hot components

was creep. They were thus designed using

creep-resistant alloys and their stresses were

controlled appropriately. In the new era of

multi-starts, the components experience

high thermal transients during startup, and

this, together with ever-shortening ramp-up

times and increasing operating cycles, has a

significant detrimental effect on their integrity.

Multi-starts mean the stressed components

in gas turbines are now subjected to low

cycle fatigue and, for many, this becomes the

dominant failure criterion. Hot components

have the added problem of creep, as outlined

above. This, when combined with low cycle

fatigue, can reduce the component lifespan

dramatically below that expected of each

of these failure criteria in isolation. Historically,

assessing low-cycle fatigue damage has been

problematic. While inspection and evaluation

of creep damage is fairly straightforward, forlow-cycle fatigue analytical methods provide

the most effective way of knowing the extent

of life remaining in a component.

The difficulty in assessing low-cycle fatigue

damage lies in the physical differences

between the characteristics of creep failure

and low-cycle fatigue during the strain cycle.

In creep failure, materials develop defects

in features such as grain boundaries, over

time and under the application of steady

stresses and temperatures, due to the

gradual accumulation of strain by diffusional

processes. Creep-resistant materials are

developed with large-grain structures to

minimize the potential for the onset and

accumulation of damage, which generally

appears at the grain boundaries.

Low-cycle fatigue, in comparison, is

characterized by the accumulation of micro-

cracks, which appear in regions of high strain.

These micro-cracks then coalesce to form

large cracks and these can propagate quickly

through the grain structure. Low-cycle fatigue-

resistant materials are typically developed

with small grain structures to cut the potential

for crack growth in any given cycle.

Analysis typically focuses on up to

ten components where, should they fail

prematurely, a safety-critical or financially

unacceptable impact would result. Each

component is modelled using a Finite Element

Model (FEM), which accurately represents

its geometry, its interaction with matingcomponents, and its load cycles. The FEM

model is then subjected to startup, steady

state, and cool-down cycles of thermal and

mechanical loads, and the results measured.

Typically, the models are non-linear to enable

them to accurately represent the gaps, friction

and material yield and creep deformation that

generally occur in hot gas path components.

Post-processing of the resulting strain cycle

produces a calculation of the damage

accumulated during each cycle type.

Methods for calculating the damage differ

depending on the material, and are based

on either ductility exhaustion or strain energy

density. For ductility exhaustion, its essential

Turbine trauma:the riskof the start-stop cycle

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Gas turbine maintenance

that we understand the dependence of the

materials ductility on complex variables,

including strain rate and temperature.

Alloys, for example, will usually have greaterductility at high strain rates than at low strain

rates. Thus, whether strains occur during long

periods of constant load or during loading

cycles will affect the damage calculation. The

available ductility of the material is gradually

used up as the strain accumulates during a

constant load period or a start/stop cycle,

until eventually it is fully exhausted.

Similarly, strain energy density-based

methods will calculate the work undertaken

by the material each time it goes through a

load cycle. From this analysis we can develop

a detailed understanding of how damage

accumulates during varying load cycles and

periods of constant load. This, in turn, provides

us with significant insights into, and a deeper

understanding of, the effects that result from

different operating regimes.

With analysis demonstrating the low-cycle

fatigue and creep stresses that multi-starts

impose upon components, and the resulting

impact that this has on their lifespan, this poses

several issues for operators. The first is the need

to be aware of the damage taking place, so

that regular inspection, maintenance and

replacement can be factored into assetmanagement strategies and schedules.

Consideration of the bigger picture,

however, poses a more complex question:

Are multi-starts cost-effective do the overall

financial benefits really outweigh the costs of

regularly ramping up the turbines so quickly?

Taking the damage that is being caused to

assets together with associated costs such

as time lost to equipment shutdowns and

time spent in repair activity by staff into

consideration, an operators apparent profit

could be significantly eroded.

Of course, apart from the financial aspects,

operators must consider the potential health

and safety implications of asset damage.

As component stresses begin to occur,

the possibility of a premature catastrophic

equipment failure increases. These failures

might involve blades, veins or even discs, and

could cause both internal damage to the

turbine and damage to surrounding areas.

Thus the problem facing industrial gas

turbines is clear. Designed for creep resistance,

using creep-resistant materials suitable for

machines which base load with minimal

start/stop cycles, the introduction of severefatigue cycles into the mix poses a significant

challenge to their long-term health.

It is imperative that operators recognize

that gas turbine multi-starts may be resulting

in more damage than they are aware of. This

knowledge may then need to be taken into

account when considering the electricity

price at which generation is economical.

With the challenges already facing the

energy market, the issue of asset damage

due to multi-starts needs to be considered by

both operators and governments to ensure

that generators are not disadvantaged. With

the need for flexibility in energy provision, gas

turbine generation must remain viable.

Gary Lockis Senior Business Manager at

Frazer-Nash Consultancy.

www.fnc.co.uk



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Retrofits & upgrades

Improving gas

turbine performancewith dry air injectionIn the Middle East, gas turbine efficiency at high ambient temperatures is crucial. Ademonstration project in Saudi Arabia installed a dry air injection system upgrade

with the aim of improving fuel efficiency, writes Tildy Bayar

Demand for fuel oil for power

generation during a Saudi

Arabian summer reaches

between 420,000 and

430,000 barrels per day.

With 58 per cent of global

use, the nation is the worlds largest user of

crude oil for generating power. Iraq, Kuwait

and the UAE were ranked third, fourth and

fifth respectively; together with Saudi Arabia,

these countries account for almost 80 per

cent of the crude oil that is burned for power

generation worldwide.One company says it can potentially offer

gas turbine-based power generators savings

of over 18 million barrels of oil equivalent (or

a 5 per cent fuel efficiency improvement) per

year through its dry air injection system.

Powerphase, with offices in Florida

and Dubai, has one such system, called

Turbophase, installed at a cogeneration

plant in the US. The Morris Cogen plant, which

came online in 1997, is a 177 MW combined-

cycle facility featuring three GE Frame 6B gas

turbines with HRSGs, and a 60 MW steam

turbine. It supplies power and process steam

for a large ethylene manufacturing plant near

Chicago, Illinois. Two Turbophase modules

have been operational at Morris Cogen since

September 2014 and have accumulated over

2000 hours of operation.

In late summer 2015, Powerphase installed

its first Turbophase upgrade in the Middle

East on an operational GE 7FA gas turbine.

The company says it installed the upgrade in

four months in order to meet the customers

summer peak load requirements.

Technology configuration

In simple or combined cycle applications the

skid-mounted Turbophase system consists ofan air compressor driven by a reciprocating

engine and a heat recovery system which

captures the engines exhaust heat and adds

it to the compressor discharge, enabling the

system to match the turbines compressor

discharge temperature.

On combined cycle and cogeneration

systems, the module can be configured with

a steam turbine drive for the air compressor

which enables zero incremental air emissions

and, Powerphase says, helps improve output

from plants which are facing limits on the air

cooled condensers for the steam turbine.

The Turbophase system takes advantage

of the fact that all gas turbines loser power

as ambient temperatures or elevations rise,

explains Bob Kraft, Powerphase president and

chief executive. The system adds the air that

is naturally missing back into the turbine. The

air is injected into one or more of the existing

ports, typically about 5 per cent air, which

results in 10 per cent more turbine power.

We are the first commercial air injection

system available on market, he adds, and for

the next 18 to 20 years we expect to be the

only one because of our patent portfolio.

In the Middle East, he notes, chillers are

competitive with the Turbophase system.Chillers effectively cool the gas turbine inlet

to allow it to generate additional mass flow,

whereas we just generate it with an auxiliary

gas-driven module and drive the air into the

turbine. We do something similar but in a

much different way, and the big difference is

that we generate that air between 30 and 40

per cent more efficiently than the turbine can

generate its own air.

Chillers store cold water for 16 or 18 hours

a day, using the turbines to run an electricity-

driven chilling process. During six peak

daytime hours, the chillers cycle cold water

from a cold tank to a hot tank through the

turbines inlet to produce additional power. In

The Turbophase dry air injection system

Credit: Powerphase

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D O W N T I M E I S N O T A N O P T I O N .

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contrast, Kraft says a Turbophase unit can run

24/7. The chiller is running harder at night to

do the storage process and only gets auxiliary

power during the day. The customer generates

about six times the revenue stream with our

system compared to a chiller system.

New aeroderivative gas turbines are also

competitive. These units suffer similar output

reductions due to high ambient temperatures.

Turbophase mitigates, and in some cases

eliminates, the need to install new peaking

gas turbines by providing an alternative at

much better fuel efficiency, Kraft says.

And, he adds, the Turbophase system has

other advantages. Especially in the Middle

East, maintenance is expensive so they try

to drag out their outage intervals. With our

system you get the extra power at the same

internal temperatures to the turbine, so you

dont affect whats going on there. If you dont

need the extra power, if youre operating at

base or part load, you can still use our air in

the system to get the efficiency improvement

but youll also get a secondary benefit: parts

life extensions.

For big companies in the US, this can push

their outage interval from basically a 24,000-

hour interval, which is the normal interval

OEMs offer today, to adding an additional year

or so, from 8000 hours to 32,000 hours. Take a

$5 million outage: instead of every three years

you can do it every four years, and youve

avoided lost revenue from the downtime.

Project specifications

The installation in Saudi Arabia was designed

to demonstrate the Turbophase systems

performance at high ambient temperatures.

The project was operational between mid-July

and early October 2015.

Powerphase requested any F-class units

for the installation of its system, and a GE-

MS7001FA-(7FA.03) gas turbine was selected.

Depending on the vintage of the turbine,

Kraft says, a B-class GT, whether a GE, Siemens,

Mitsubishi, those were developed and

delivered in the 1960s and 70s. In the 70s and

80s there was the E-class; the next generation

of GTs out there in significant quantity are the

D and E classes. In the 90s the F class came

out, and now in the 2010 frame and above,

the H and J class. Those GTs basically have

an increased firing temperature, which is the

temperature that the GT inlet sees.

The efficiency of the GT and the CCGT are

directly proportional to the firing temperature.

So basically, for every unit of air that the GT

pumps through it with the compressor, it

makes more power in the turbine and steam

turbine with the elevated firing temperature.

The reason we like the F-class units is

because they are today considered mature-

frame GTs, so there are a lot of competitors

out there supplying parts and services

and customers are used to operating and

maintaining those GTs. So we can sell a

third-party product to them and they feel

comfortable putting it on.

Our box works on every GT on the planet,

but on those B-class machines it might make

3 MW per box whereas on a J machine it

will make 6 MW per box with the same fuel

consumption and air output.

On more advanced frames you will see

some of the OEMs offering our equipment.

This business works nicely with OEM offerings.

It could be viewed as a competitive product

because OEMs like to upgrade their GTs,

however its such a unique product and we

see OEMs moving towards putting it on their

engines, either in new or existing offerings, onboth mature and advanced fleet GTs.

Due to schedule constraints, it was decided

to not install a complete system consisting of

five or seven Turbophase modules (TPMs)

on a single F-class turbine. Instead, two TPMs

were installed to demonstrate performance

and the resulting values were extrapolated to

model a complete system.

In May, before the installation of the TPMs,

a boroscope inspection of the compressor,

combustor, turbine and exhaust was carried

out. The compressor, combustor and exhaust

were found in the expected condition for the

turbines operating hours. The turbine portion,

however, was heavily eroded, with significant

gaps between stationary and rotating parts.

The customers engine was about ready

to go into outage so they basically took a GT

that they were going to do a major overhaul

on anyway and let us install there, says Kraft,

adding that we made our incremental power

and efficiency even on a GT that was basically

worn out. It was a little risky if the GT broke, we

would get blamed. Because of our extensive

background on this type of gas turbine, we

were confident that even though the GT was

heavily deteriorated, there wasnt going to be

any failure.

The go-ahead for the project was given in

early March, and in mid-July the first injection

was made. Due to the short time period

available, Powerphase needed to adapt

some of the auxiliary systems. The TPMs power

supply was planned to be provided from the

turbines motor control centre (MCC). Due to

logistics issues with material deliveries and

cable installation from the MCC to the TPM

location, which was some distance from the

plant, it was decided to use diesel generators

to supply the required power.

This choice worked out well for us, from two

perspectives, Kraft says. One, it was very easy

for the customer to look at the diesel gensets

power output and be able to calculate

that the Turbophase modules electricity

consumption was on the order of 35 kW, which

is about 0.5 per cent of the power that we

make. So our box makes 4.5 MW; 99.5 per centof that goes to the grid and 0.5 per cent goes

to internal loads if its hooked up to a power

plant electrical system. In this case it was all

to the grid, but the customer could easily see

what the power draw was and we also had

a cooling system that took some power. But

most of our installations are going to be of a

nature where the plant is providing cooling

water, so the auxiliary load is just the module.

A second benefit: the customer is able

to get comfortable with what happens if our

system trips offline. Our diesel genset ran low

on oil or had some issue and quit running in

the middle of the night while we were injecting

air, so we had an unplanned trip test. The

Number of TPMs 1 2 3 4 5 6 7

Incremental power MW 4.50 9.00 13.50 18.00 22.50 27.00 31.50

GT HR improvement % 0.70 1.40 2.10 2.80 3.50 4.20 4.90

Figure 1. Predicted incremental output with additional TPMs on the gas turbine (5% air flow) at 2420F firing

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customer wanted to make sure we were not

going to harm their GT if something goes afoul

on our end, and we were able to prove that by

shutting off the fuel to our system.The expected performance for the two

TPMs was calculated based on the turbine

model type and a constant firing temperature

of 2420F.

z Expected Output: 4.5 MW incremental

power for one TPM, 9 MW in total for both;

z Minimum Output: 4.05 MW incremental

power for one TPM, 8.10 MW for both;

z Heat Rate:Consistent with 5 per cent plant

heat rate improvement.

Based on the 5 per cent plant heat rate

improvement from a full TPS installation, the

predicted heat rate improvement per TPM was

around 0.7 per cent at 4.5 MW incremental

output and 2420F firing temperature.

Firing temperature impacts the turbines

output, which is defined as MW/(lb/s). The

higher the firing temperature, the more output

per lb/s of air flow and the more additional

output per lb/s of air and steam injection.

The OEMs design data for the GE-

MS7001FA-(7FA.03) specifies performance at

a firing temperature of 2420F. However, due

to its degradation, Powerphase estimated

that the turbine was actually operating

at a firing temperature of 2370F. This was

confirmed in site operations and validated

with a ThermoFlow model matching the site

operating conditions. This deviation had an

impact on both the turbines and the TPMs

performance. Powerphase noted that, if the

turbine had been firing at 2420F as designed,

the incremental output per TPM would have

increased by 0.2 MW.

Hitting targets

The initial performance test was conductedon 28 July. The Turbophase system achieved

its output and heat rate targets of 4.5 MW per

TPM and 5 per cent heat rate improvement

for a full installation. These values are based

on the measured performance corrected for

firing temperature and extrapolated to a full

installation. Every day the system was turned

on and off and you could see the incremental

power and efficiency, says Kraft.

At the customers request, a second

performance test was conducted in early

September and confirmed the results of the first

test. In both cases, the upgrade demonstrated

that a full installation of seven TPMs per turbine

would produce a 5 per cent fuel efficiency

improvement and 31.5 MW power increase

on the 7FA gas turbine. Additionally, the

system demonstrated as high as 99.3 per

cent availability in ambient conditions upto 55C. The fuel efficiency improvement was

demonstrated at both baseload and part-

load operating conditions.

The turbine was set to baseload select for

the duration of the performance test. During

the testing the fuel gas compressors were

operational, which ensured a ~50 psi delta

pressure across the turbines stop ratio valve

(SRV) at all times. The generator readings were

recorded as found. However, the recorded

values for single TPM injections included

the other TPM in cool-down/standby mode,

which added another ~40 kW. The cooling

water system was also running double to

support both TPMs even when only one was

operational. For these reasons, the generator

loading recorded values were divided by two

to provide more accurate results, as if only one

TPM was operating.

During commissioning of the TPM,

injection tests were performed at various inlet

conditions. A change in inlet temperature

resulted in a change in gas turbine base

output. Much care was taken to go through

the data and match up inlet temperatures as

closely as possible to show the incremental

output at the same temperature. OEM inlet air

temperature correction factors were not used,

as they would scale the incremental output

up or down.

It was also observed that there were swings

in the turbines fuel flow for constant turbine

output, which would indicate that either the

flow meter had some drift or fuel content was

swinging during the testing.

After the first injection into the turbine the

hot commissioning phase was conducted,followed by the performance test. The first two

weeks after the performance test were used to

address commissioning issues on the system.

In the weeks of operation, about 3.2 GWh

were produced by the TPMs and provided

to the grid. The TPMs availability was above

97 per cent.

At the as-found condition of the turbine,

each TPM added 4.25 MW at 8650 BTU/kWh

to the GT, for a total of 8.5 MW at 8100 heat

rate. (The fuel flow readings from the gas

turbine OEM flow meter are not accurate or

stable enough to confirm the heat rate output.

Performance calculations showed the heat

rate closer to 8000 BTU/kWh.)

By extrapolating the TPMs output from the

current firing temperature of 2370F to the

design point of 2420 F, the output increases to

4.5 MW at 7600 BTU/kWh heat rate.An installation of five modules would

result in an output increase of 22.5 MW. At an

ambient temperature of 50C, this results in a

19 per cent output increase and 3.5 per cent


An installation of seven modules would

result in an output increase of 31.5 MW. At

50C ambient temperature, this results in a

26 per cent output increase and a 5 per cent


A new business model

A turbine has to be down for six weeks or

more if youre installing a new hot gas path

or putting on an inlet cooling system youre

basically building a power plant, Kraft says.

Our system can load follow at the end of

the day its really just a reciprocating engine

driving the process, so we can move it around

quickly we have one air pipe that hooks to

the GT and, in both installations so far, outage

has been less than one day. So when the

plant is down for something else, we tie in

and were done. There can be a month or

two of relatively minor site work, the primary

piece being the air pipe and fuel line. So its a

really simple installation and leads to unique

opportunities in that we can do something like

the aircraft business does: power by the hour.

Most engines on airplanes are leased

rather than owned, he explains. You run it

for a certain number of hours and turn it in,

get a new one, and keep going like leasing

a car. Our system is extremely quick to install

or uninstall; the installation part is typically

between 5 and 10 per cent of the overall cost

to the customer, and we offer a leasing model.If youre putting an inlet chilling system

on a GT youre buying it, and its only good for

that GT. Our system works on all of the GTs at

the plant that its piped to; we can pipe it to

all of them, and you can lease it for a short

period of time while building a new plant or

just for the summer. This business model hasnt

been around the large frame GT business

ever. There have been businesses like this for

the aeros several of the OEMs offer mobile or

relatively mobile aeroderivative engines but

nothing on large frame GTs.


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Gas turbine filtration


The cost of

ineffective filtrationWhen selecting a high efficiency particulate air filtration solution, what factors

need to be considered to optimize turbine efficiency, reduce maintenancefrequency and give a better overall return on investment for a particular

installation? Steve Hinerhas some answers.

Gas turbine inlet filter

performance directly

impacts the efficiency of

the turbine plant in terms

of power output and

heat rate loss.

Turbines consume vast amounts of air

and an effective inlet filtration system is

vital to maintaining optimum performance

and reducing the need for maintenance

shutdowns. Ineffective filtration solutions will

lead to problems in turbine performance that

will require operator intervention. The level

of impact will depend upon environmental

conditions on-site and this means that afiltration solution needs to be designed with

an understanding of the local installation

conditions. Depending where the turbine

is installed, the filtration system may need

to handle sand, salt, dust, hydrocarbons,

moisture or even snow and ice.

Fine particles entering a turbine can stick

to turbine blades. This creates fouling which, as

it builds up, affects the turbines aerodynamic

performance. As output power reduces and

heat rate rises, the operator will need to take

the turbine offline to wash the compressor and

restore its performance. The reduced turbine

efficiency and the lost production time when

it is taken offline have large cost impacts in

terms of lost MW output and more fuel burned.

High efficiency particulate air (HEPA) filters

offer greater levels of protection and so, in

theory, will help to improve plant performance.

However, the use of finer filters also presents

challenges in terms of filter life. It has been

shown that standard filter efficiency ratings

from standardized laboratory-based filter

testing do not necessarily result in the same

performance when operated in the real world.

Moisture and hydrocarbons found at site can

cause sudden blockages that may result in

pressure loss spikes and equipment downtime

or damage.

Comparing performance

Filter solutions may generally use either

microfibre glass (glass fibre) or membrane

media, typically ePTFE, to achieve higher

HEPA efficiency. Microfibre glass has

historically been the more popular choice

in industrial environments as it offers robust

and predictable filtration performance. ePTFE

membrane technology is relatively new to this

application, so how can operators determine

which is best for their installation?

Both microfibre glass and ePTFE media

types can achieve HEPA level performance

with (H)EPA ratings of E11 or E12 to the

international standard EN1822. Fundamentally,

a higher filter efficiency requires finer media to

filter out smaller particulates.

One of the differences between microfibre

glass and ePTFE is the thickness of the media

used to achieve this. Microfibre glass filters use

a deeper filtration layer whereas membrane

solutions use a single, very thin layer. The

problem is that the reduced total filtration

volume means membrane technology can

be more sensitive to blockage from moisture

and hydrocarbons.

Hydrocarbons can find their way into a

turbine inlet as the result of many processes,

including the by-products of combustion such

as soot or unburnt fuel, oil vapour from lubeoil vents, and general atmospheric pollution.

When combined with moisture they can cause

filters to block and, if the filter is not designed to

handle this, blockages may occur very quickly

and without reasonable warning. As the

turbine strives to suck the air it needs through

its inlet, the filter blockage causes an increase

in pressure drop. Sudden pressure loss spikes

can result in costly unscheduled downtime or

even damage to machinery or ductwork.

ePTFE membranes have a thin, two-

dimensional layer of high efficiency media

which can quickly become blocked by

moisture droplets. This media has been shown

to be prone to sudden blockages and high

A comparison of two gas turbines operating side-by-side at the same site shows the impact filtration can have

Credit: CLARCOR

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Successfully proven in commercialoperation: the H-class from Siemens.Outstanding flexibility meets groundbreaking efficiency.

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differential pressure spikes. Plugging has been

seen to occur anywhere from as little as three

weeks after installation and requires urgent

remedial maintenance to prevent wider

system damage. It is this unpredictability which

means further research and development into

this type of technology is required to make it

more robust for heavy industrial applications.

Microfibre glass media is around ten times

thicker than a typical ePTFE membrane. Its

greater pore volume makes it naturally less

prone to sudden blockages, while its depth

maintains an equivalent high particulate

efficiency. Any pressure loss increase across

the system has been proven to happen

much more slowly than with ePTFE, givingthe operator plenty of time to take action

and making this type of media much more

predictable in its performance.

Why is the thicker media with greater pore

volume less prone to blockage when moisture

is present? First, lets define the moisture that

causes the problems. High humidity does not

necessarily create an issue as this is not in

droplet form and passes through the system

with the air. If there is a lot of water, perhaps

due to heavy rain, this is also not generally a

problem as the large water droplets bounce

off the filter or drain down the surface of the

media.

Mist and fog, however, have droplets that

are of a comparable size to the fine particles

filtered by HEPA filters and so a mist or fog

event is equivalent to a sandstorm of very

fine particles causing similar effects in the

filter, where the droplets get into the media

and clog it. Liquid droplets, once within the

matrix of the media, combine and would

normally drain out, but when a filter is loaded

with hydrocarbon, this changes the surface

tension on the media fibres. The water droplets

are then more likely to cling to the fibres and

remain within the media matrix, causing

blinding and a high pressure loss.

Filter construction

Microfibre glass and membrane technologyachieve high efficiency filtration in different

ways. Microfibre glass media uses its depth to

capture particles which have to travel through

a tortuous path inside the matrix. Membranes,

however, use a thin layer of finer pores which

create a sieving effect. This means the pores

inside the microfibre glass media are larger

and small water droplets are more likely to

work their way through and, even if they

remain within the media, they are less likely to

plug the higher volume of larger pores.

As well as selecting an appropriate media

type, filters also need to be robust to ensure

their reliability. If particulates are allowed to

bypass the filter media, its efficiency rating is

useless.

Using the right glue, avoiding glue beads

that may fall off once a filter is installed, and

ensuring that the overall filter design is robust

are important considerations. Features such as

seamless gaskets on filters also help to prevent

leaks during operation. Frame materials

should always be selected to handle the

installations environmental conditions and

designed to remain robust after aging.

One problem operators face when

selecting a filtration solution is that standard

efficiency ratings do not necessarily reflect

how a filter will perform in the real world.

Current ratings are based on laboratory

testing that does not cover the wide variety ofconditions and environments a turbine may

be subjected to.

Take, for example, the hydrophobicity of a

filter: its ability to prevent liquid and salts from

passing through, causing turbine corrosion

and accelerated fouling. This should be a

major consideration for the power industry,

but there is no industry standard test to

rate the performance of a filter in this area.

CLARCOR uses a patented hydrophobic test

to determine the performance of its filters. It is

designed to test areas such as salt leaching

and takes the filter through a total of nine wet/

dry cycles within a ten-day protocol to simulate

filter performance in real-world installations.



Fibreglass is able to handle moisture better than membrane due to its thickness

Credit: CLARCOR

The difference between filters that are both

classified by manufacturers as hydrophobic

Credit: CLARCOR

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23/52www.PowerEngineeringInt.com 21



A major gas turbine supplier recently carried out comparative tests

on the performance of equivalent ePTFE membrane and microfibre

glass HEPA products. The tests covered overall efficiency, pressure loss,

hydrophobic performance, wet performance and the dust-holdingcapacity of each technology. Microfibre glass filters showed equal or

better performance than ePTFE at a lower cost. The gas turbine supplier

then chose the microfibre glass filter as its filter of choice for its next-

generation technology.

Overall, the real-world performance of gas turbine filters has

shown that, for the moment, microfibre glass technology offers a more

predictable and reliable solution than membranes such as ePTFE

media. It offers a higher pore volume which is less sensitive to plugging

with moisture and hydrocarbons while providing the same dust filtration

efficiency.

The predictable nature of microfibre glass filters means they have a

much longer life, with a gradual increase in pressure loss over time that

is less likely to trip turbines or require unexpected maintenance. They

offer a robust, lower-cost, longer-life (H)EPA filter solution.

Although ePTFE membrane filters can offer a typical lifespan of

two years, this is much shorter than microfibre glass equivalents. The

unpredictable nature of membrane filters further means they require

much closer monitoring and any change-out needs to happen

quickly to avoid damage to other systems. Overall, they may currently

appear to offer a good solution, but operators should take into account

maintenance frequency and lifetime costs when considering their

selection.

What may the future hold?

Industry experience indicates that microfibre glass technology offers

operators greater peace of mind with regard to predictable, reliable

turbine output.

For this reason, CLARCOR does not currently recommend the

use of ePTFE media on turbine installations. CLARCOR is an in-house

manufacturer of ePTFE membrane, uses it successfully in many of its

other filtration products, and would like to be able to provide it for GT

inlet filtration but the global diversity in ambient air contaminants

makes its performance just too unpredictable today for use with gas

turbines.

As membrane technology continues to be developed, however,

improvements in its sensitivity to moisture and hydrocarbons may well

make it a good option in the future. Other materials such as nanofibresalso continue to be developed. These are synthetic polymer-based

media very similar to microfibre glass that may soon offer a further

viable alternative solution with HEPA filtration efficiency levels.

Testing standards continue to be researched and developed for

the implications of different environmental factors on the performance

of a filter and, therefore, the performance of turbines is more clearly

understood. Hopefully, in the near future, standards will give operators

a more comprehensive evaluation of how a filter will operate in the real

world.

Steve Hiner is Chief Engineer, Gas Turbine Inlet Systems at CLARCOR

Industrial Air. www.clarcorindustrialair.com



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7/26/2019 pei201604-dl


Gas Turbine Technical Specifications - Simple cycle

Manufacturer ModelGross output

(MW)Heat rate(kJ/kWh)

Gross efficiency(%)

Shaft speed (rpm)Pressure

ratio

Ansalso Energia

AE64.3A 78 9917 36.3 3000/3600 18.3AE94.2 185 9945 36.2 3000 12

AE94.2K 170 9863 36.5 3000 12

AE94.3A 310 9045 39.8 3000 19.5

AE-T100 0.1 12,000 30 70,000 4.5

GE

TM2500 34.3 10,197 35.3 3000 24.5

LM2500 23.8 10,606 33.9 3000 19

LM2500 DLE 22.4 10,167 35.4 3000 18.1

LM2500+ 30 10,154 35.5 3000 23.1

LM2500+ DLE 31.1 9674 37.2 3000 23.6

LM2500+ G4 34.5 10,209 35.3 3000 24.6

LM2500+ G4 DLE 33.4 9671 37.2 3000 24

LM6000PC 45.4 8973 40.1 3627 29.7

LM6000PC Sprint 51.1 8922 40.4 3627 31.5

LM6000PF 45 8573 42 3627 30.1

LM6000PF Sprint 50 8580 42 3627 31.6

LM6000PG 56 8974 40.1 3911 33.5

LM6000PG Sprint 59 9035 39.8 3911 34

LM6000PF+ 53 8603 41.8 3911 32.1

LM6000PF+ Sprint 57 8693 41.4 3911 34

LMS100PA+ 114 8319 43.3 3000 42.5

LMS100PB+ 108 8204 43.9 3000 42.2

6B.03 44 10,740 33.5 5163 12.7

6F.01 52 9369 38.4 7266 21

6F.03 82 9991 36 5231 16.49E.03 132 10,403 34.6 3000 13.1

9E.04 145 9717 37 3000 12.3

GT13E2 2005 185 9524 37.8 3000 16.9

GT13E2 2012 203 9474 38 3000 18.2

9F.03 265 9517 37.8 3000 16.7

9F.04 281 9316 38.6 3000 16.9

9F.05 299 9295 38.7 3000 18.3

9F.06 342 8768 41.1 3000 20

9HA.01 429 8483 42.4 3000 22.9

9HA.02 519 8440 42.7 3000 23.8

TM2500 37.1 9676 37.2 3600 24.7

LM2500 24.8 10,265 35.1 3600 19

LM2500 DLE 23.2 9830 36.6 3600 18

LM2500+ 31.8 9761 36.9 3600 23.1

LM2500+ DLE 31.9 9269 38.8 3600 23.1

LM2500+ G4 37.1 9676 37.2 3600 24.7

LM2500+ G4 DLE 34.5 9188 39.2 3600 23.6

LM6000PC 46 8924 40.3 3600 29.6

LM6000PC Sprint 52 8909 40.4 3600 31.3

LM6000PF 45 8543 42.1 3600 29.8

LM6000PF Sprint 50 8555 42.1 3600 31.4

LM6000PG 56 8993 40 3905 33.5

LM6000PG Sprint 59 9053 39.8 3905 34

LM6000PF+ 53 8625 41.7 3905 32.1

LM6000PF+ Sprint 57 8711 41.3 3905 34

LMS100PA+ 117 8190 44 3600 42.5

LMS100PB+ 109 8172 44.1 3600 42.1

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25/52www.PowerEngineeringInt.com 23Power Engineering InternationalApril 2016


Exhaustmass flow

(kg/s)

Exhausttemperature

(C)NOx emissions (ppmv)

Weight(tonnes)

DimensionsL x W x H (metres)

Notes

215 573 25 61 5.9 x 3.1 x 3 AE64.3A with gear (gas turbine 90 Hz)555 541 25 233 10 x 4 x 3.7

540 545 25 190 10.2 x 4 x 3.7 Performance with low heating value gas

750 576 25 317 10.8 x 5.1 x 4.9

0.8 270 15 2.77 3.9 x 0.9 x 1.8 Microturbine

92.5 517 25 112 32 x 3 x 4

71.3 530 25 113 17 x 3 x 3 Water injection

68.4 547 15 113 17 x 3 x 3 DLE


88.8 539 25 113 17 x 3 x 3 DLE

96.6 519 25 113 20 x 3 x 3 Water injection, gearbox

93 552 25 113 20 x 3 x 3 DLE, gearbox



127.3 457 15 305 20 x 4 x 5 DLE, gearbox

132.7 459 25 305 20 x 4 x 5 DLE, gearbox



135.3 500 25 305 20 x 4 x 5 DLE, gearbox

143.2 490 25 305 20 x 4 x 5 DLE, gearbox


227 421 25 897 34 x 24 x 15 Water injection

145.1 548 4 100 13 x 4 x 4 Available in 50 Hz & 60 Hz

126.1 603 25 70 6 x 4 x 4 Available in 50 Hz & 60 Hz

213.2 613 15 100 10 x 4 x 5 Available in 50 Hz & 60 Hz419.1 544 5 214 11 x 5 x 5

415.5 542 15 219 11 x 5 x 5

567.4 505 25 343 11 x 6 x 5

624.1 501 15 350 11 x 6 x 6

665 596 15 308 11 x 5 x 5

667.2 608 15 308 11 x 5 x 5

666.8 642 25 322 11 x 5 x 5

731.2 618 15 386 11 x 5 x 5

826.4 633 25 386 11 x 5 x 5

995.6 636 25 432 12 x 5 x 5



68.2 539 15 113 17 x 3 x 3 DLE


87 526 25 113 17 x 3 x 3 DLE


91.5 535 25 113 20 x 3 x 3 DLE

129 440 25 305 17 x 4 x 5 Water injection


125.6 461 15 305 17 x 4 x 5 DLE

131.4 463 25 305 17 x 4 x 5 DLE



135.1 500 25 305 17 x 4 x 5 DLE, gearbox

143.1 490 25 305 17 x 4 x 5 DLE, gearbox230.7 416 25 897 34 x 24 x 15 Water injection

226.8 418 25 897 34 x 24 x15 Water injection

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Manufacturer ModelGross output

(MW)Heat rate(kJ/kWh)

Gross efficiency(%)

Shaft speed (rpm)Pressure

ratio

GE(continued)

6B.03 44 10,740 33.5 5163 12.76F.01 52 9369 38.4 7266 21.0

6F.03 82 9991 36.0 5231 16.4

7E.03 91 10,614 33.9 3600 13.0

7F.04 198 9327 38.6 3600 16.7

7F.05 241 9052 39.8 3600 18.4

7F.06 270 8704 41.4 3600 22.1

7HA.01 280 8630 41.7 3600 21.6

7HA.02 346 8525 42.2 3600 23.1

Kawasaki Heavy Industries, Ltd

GPB300D 30.1 8977 40.1

9330/5600 (gas

generator rotor/

power turbine

rotor

24.5

GPB180D 18.4 10,526 34.2 9420 18.3

GPB80D 7.8 10,714 33.6 13,800 15.9

GPB70D 6.7 12,000 30 13,800 15.9

GPB50D 4.8 10,905 33

GPB17D 1.7 13,382 26.9 21,965 10.5

MAN Diesel & Turbo SE

THM1304-10N 10.5 11840 30.4 9000 10

THM1304-12N 12.5 11320 31.8 9000 11

MGT6100 6.63 11190 32.2 1500/1800 14

Mitsubishi Hitachi Power Systems, Ltd

H-25(28) 28.13 10,527 34.2 7280 14.2

H-25(32) 32.3 10,338 34.8 7280 15.4

H-25(35) 37.69 10,288 35 7280 17.7

H-25(42) 42.03 9664 37.2 7280 17.5

H-50 57.45 9508 37.8 5040 19.5

H-100(100) 99.

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