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DOCUMENT CONTROL

RAILBELT ELECTRICAL POWER ALTERNATIVES STUDY

TECHNOLOGY PROFILES:

Cor~BUST ION TURBIN ES

by

EBASCO SERVICES INCORPORATED

DRAFT

JANUARY 1981

7'1

II I" Project Economics •• "...".. • • • • • • • • .. • • •

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TABLE OF CONTENTS

.0. .0. . . . • . . . • . 0 • . .La nd Us e • • e • " • • " • • • • • • • • " • • •

Labor Force and Employment .Fl ow of Capital and 0 and ~1 and Fuel Expenditures

••..1. _;.~ n)I.t t·· ~ ,'-.Q Kt_q:,. t\

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Water Resources e • • • • • • •

Air Resources .Biota .• • •• • • • • . • • • • . 5 • • •

Aesthetic Intrusivenesss •• " .No n-Renewab1e Resources •• • • " " • " • •Health and Safety ...... ~ •••••••

Capital Costs •• " •• Ii .

Fuel Costs • • • • .. • • .. • • • .. • • • • • " • •Fuel Transportation Costs •••• " .Operation and Maintenance Costs ..

Iechntcat Description

Environmental Impacts

A. General Description .B.SitingRequirements ' ••••••C. Fuel Requirements " •• " " ..D. Technical Considerations ••••••••••••••••E. f\pplications of the Technology .

Gommerc ial ~laturitYIStatus

Socioeconomic Impacts

A.B"e"D.

A.B.C.D.E.F.

A.B.c.

IV.

v.

II.

I.

Summary.,. • • .. •• • .. .. • •

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TABLE OF CONTENTS

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· . ..

• •

• • •• • •

• • •• • •

• a • • • • • • ~ • •

• • e • • • • • • e •

• • • • • • • • 0 • •

· . . . . . . . . ~ .· . . . . .0. . . .

• • • • 0 • • • •

• ••••••••••••••

• • • • • • • • • • • • • •

and Fuel Expenditures

• • • • • 0 • • • • • • • , •

• • •

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• •• •

• • • • • • ~ • • ea.' • • • • • • •

•• •

• • • • • • • • • • • • • • • • • • •

• • • 8 • • e • • • • • • • • • • • • • •

Land Use •• • • • • • • •Labor Force and Employment .Flow of Capital and a and ~1

;.rt:. -U..a Rl~91U\\J

General Description • • • • • .. •Siting Requtrements It ••

Fuel Requirements .Technical Consioerations •••••Appl teat ions of the Technology e •

Capital Costs •••••••••••••••Fuel Costs •• • .. • e • • .. • .. • • .. • .. ..

Fu e I Tr ansportat i on Co Sts .. .. II .. .. .. .. .. •

Operation and Maintenance Costs •••••••

Environmental Impacts

Commercial NaturitY/Status ..

l'echnical Description

A.B.C..D.E.

A. Water Resources • • • .. • • • • • • •B. Air Resources ..c. Biota ..., ~ . • • • • • • • g • • • • • • • • • 8 G

De Aesthetic Intrusivenesss •• It It ..

E. Non-Renewable Resources .. • • • • .. • • • • • .. .. .. • •F. Health and Safety .

Socioeconomi c Impacts

A.B.c.

A.B.c.D.

IV.

L.

v.

I I.

III. Project Economies

Summary.. • •• •• .. • •• •

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L1ST OF TABLES

Table No • Ii tle

1 SUMMARY OF COMBUSTION TURBINE CHARACTERISTICS

2 CONVERSION EFFICIENCY OF A COMBUST ION TURBINEAS A FUNCTION OF PLANT SIZE

3 SUNMARY OF CO~lBUSTION TURBI NE PROJECT ECONOMI CS

L1ST OF FIGURES

Figul"eNo~

1 SIMPLE CYCLE COMBUSTION TURBINE

2 POTENTIAL SITES FOR COMB;USTION TURBINES IN. RAT LBELT REG ION

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RAILBELTELEC1RICAL POWER ALTERNATIVES STUDY.. TECHNOLOGY PROFILES: COMBUSTION TURBINES

SU~l~1ARY

TheCDmbustion turbine power plant is one which utilizes a specially

constructed turbine engine as the prime mover. This engine, which isvery similar to a typical aircraft jet engine, can burn either. liquid

or gaseous fuel. The. fuel is burned continuously in the presence ofcompressed air, and the hot exhaust is allowed to expand through apower turbine. The power turbine is coupled to an electric generator

which then produces electricity.

Combustion- turbines have been used for nearly two decades in theutility industry to provide peaking and emergency power generation.

They are readily suited tocycl tc duty operation, and they can be

brought on line quickly from a cold start. Because of their

simplicity, combustion turbines are ideally suited for operation ;n

remote locations, and they can be operated unattended if necessary.

The main disadvantages of combustion turbines are their relative

inefficiency when compared to large conventional fossil plants, and the

fact that the petroleum based fuels which are most readi ly used by

combustion turbines are in short supply.

The two disadvantages can be overcome by incorporation of gas. turbines

into more efficient cycles (such as combined cycle or coger-t!ration),

and the development of synthetic fuels. In such cycles, increased

thermodynamic effic iencies stem from the USe of rejected heat.

From a cost standpoint, combustion turbines have the advantage of

having the lowest capital cost of any conventional power generating

facil ity. Their f'uel costs are normally higher, however, and it is

this increased fuel cost which generally plays an important role fn

determinn19 the economic feasbilityat their installation.

i

Characterist ics

TABLE 1

$UMMARYOF COMBUSTION TURBINE CHARACTERISTICSSheet 1 of2

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Factors

Technical

1. Typical System Range

2. Electrical PowerPotential

3. Fuel Requirements

4. Efficiency ofGenerating Electricity

5. Siting Requirements

6. Potential Sites

Commercial Maturity

1. Commercial Status

2.. Barriers to IncreasedDevelopment

Project Economics

1. Capital Costs

2. Operation andMaintenance Costs

60 - 200 MW

Good for peaking and emergency powergenerat i on as well as base loadoper-ation,

Various fuel s can be ut 11 tzec ,including distillate oil, naturalgas, and synthetic fuel s. All ofthese fuels are non-renewable,except for methanol derived frombiomass.

Not veryeff1cient (34 percent).

Minimal siting constraints due toease of transporting equipment andsmall land requirements. Airemissions may constr-ain the numberand location of sites.

Numerous potential sites. Mostdesirable sites located adjacent togas and oil pipelines, or railroad.

Commercial availability and use byutil ities since 1960.

Combustion turbines is a mature,proven, technology. Increasedutil fzation of combustion turbinesis constrained by rising fuel prices.

Economies of scale extst , 50-100 NW- $350/k~J. Under 50 NW - Z450/kW.

largelY a function of systemapp ltcati on, e.g., base or peakingpower.. Average costs - 4-5mill slkWh.

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Factors

Impacts of Technology.

1. En vtronmenta1

2. Socioeconomic

TABLE 1 (Continued)

She.et.2 of 2Characteristics

Air Emissions - SOx, NOx, CO,hydrocarbons, and particul ates.

- Potential habitat disruption.Po tent.;~--impa..·trment_o.f--v·is-i-b.:i.l;j t-y

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Minimal Or no impacts.

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RAILBELT ELECTRICAL POWER ALTERNATIVES STUDYTECHNOLOGY PROFILES: COMBUSTION TURBINES

I. Technic~1 Description

A. General Description

.Un l tke conventional fossn-fired and nuclear power generating

stations, the combustion turbine uses hot exhaust gas instead

of steam to drive the turbine generator. Liquid or gaseous

fue'! is ignited in a combustor under a pressure of 150 to 225

psi, and the hot exhaust gas isa1lowed througha. series of.

power turbines. These power turbines drive not only the inlet

air compressor, but a 1so the electric power generator, asis

shown in Fig. 1. The fact that hot gas is the working fluid

in a combustion turbine gives rise to their alternative nameof ilgaslf turbine.

The most common example of a combustion turbine is the jet

engine used in today's aircraft. Combustion turbines designed

for power generation are slightly d1fferent however, since

size, \'/eight, and highly variable inlet air conditions are notoperating constraints.

The design philosophy of all combustion turbines is

essentially the same, even though individual component design

may differ. The compressor section is usually multi-staged,

utilizing. either centrifugal or axt al compressors. The

combustion secton, Where fuel and a1r are mixed and burned in

a continuous process, may cons tst ofa single combustor or up

to a dozen combustors arranged around the periphery of the

mach tna, The power turbine section is mult t-s taged, and may

consist of centrifugal or axial flow turbines. The power

turbine(s) which dr-ive the compressor stages m"ay or may not be

coupled directly to the power turbine which drives theelectric generator.

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Combustion turbines can be started and brought on line very

quickly. Even the 1arger combustion turbines are capable of

full 'load generationi;, less than a half hour after a cold

start, and some of the smaller machines requir-e only a few

minutes.

B. Siting Requirements

1. Physical Characteristics

The simple cycle combustion turbine powerplant has fewer

siting constraints than conventional fossil-fired or nuclear

plants .. Only limited space is needed, no cooling source

(e.g.t cooling tower} is required, and the presence of

operating personnel is not necessary.

The primary constraints which do exist are environmental

constr atnts. The exhaust from combustion turbines typically

contains oxides of sulfur (SOx},.oxides of nitrogen (NOx)'carbon monoxide (CO), unburned hydrocarbons, and particulate

matter. The quantity of each particular contaminant which is

emitted are a function of the size of the machine, the

manufacturer, the type of fuel burned, and the extent to which

emission control techniques are utilized. The suitability of

a particular site will depend upon the degree to which these

contaminants can be tolerated.

2. Infrastructure Requirements

Fuel storage. and handling requirements are minimal. If the

combustion turbine powerp 1ant cannot be located near oi 1

supp.ly pipel ines, site storage may be utilized. Oil can be

shipped to the site by truck, ra.il, or barge. If natural gas

is to be ut ;·1 i zed, however , a pi pel ine to the site is usually

required.

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3. - A~ai1abi1ity of Sites in Railbelt Region

Numerous potential sites for combustion turbines exist in the

Railbelt regon. The ease of siting is due to minimum

constraints ,,/hich are confined to fuel transportationrequirements. Combustion turbines need to be located adjacent

to a distribution pipeline or railroad to permit

transportation of 1arge volumes of fue 1.

Fuel Requirements

Combustion turbines can util ize a It/ide variety of natural and,/"

synthetic fuels, from heavY residual oils to medium Btr{'_,''':~/'r

synthesis gasses. The performance of the turbine varies ~/

slightly with each fuel. While the basic design of thecombustion turbine is the same, regardless of the fuel type,

some modifications in design are required. Three of the more

viable fuels, natural gas~ distillate oil~ and synfusl are

discussed below.

1. Fuel Type

Natural Gas

Natural gas is perhaps the best combustion turbine fuel from

the standpoint of performance and operating simplicity. Heat

rates are~enerallybetter and exhaust emissions, especially

for sulfurous oxides and particulates, are substantially

lower. Less maintenance is required, since the combustion

products of natural gas are not nearly as corrosive as other

liquid fuels.

One drawback to using natural gas as a fueli s that it must be

suppt ted ala moderate pressure ~ usua11 y around 300 psi g. If

the supply pressure isnotadequate t a gas compressor must be

uti 1i zed ,and this can more than offset the improved heat rate

advantage.

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D.istillate 0; I is another fuel which is v/idely used in

combustion turbine powerplants.. Like many other liquid fuels,

distillate oil can contain sulfur, fuel ash, and trace metals

which are generally not .preserrt in natural gas. Sulfurand

fuel ash contribute to exhaust emissions, and trace metals can

cause corrosion which will reduce the life of the combustion

turbine "hot path" material s. (Those parts exposed to hot

exhaust; gas.) However, the amount of contaminants in

distillate oil is generally much lower than in heavier 1iquid

fuels. A minimal amount of treatment equipment, if any, may

be required to make distillate oil an acceptable fuel.

Synfuels

Combustion turbines are capable of burning a variety of

synthetic fuels, although little operating experience has been

gaJnea to date. Th i sis due mainly to the h ighcost and

limited availability of synthetic fuels. In order to promote

further use of synfuels, the U.S. Department of Energy has

sponsored a number of test programs conducted by both

uti 1ities and equi pment mantrtacturers. It is from these test

programs that the vi abil ityof synfuel s has been determined.

Some nf the more promising synfuels are discussed below:

Low-Btu Gas:

The low-Btu gas descr.ibed here is a coal derived gas with a

heating va lue of 100-200 Btu/scf (standard cubic foot). It is

norma.Hy obtained from the fixed .bedgasification process with

air USed as the oxidant.

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The feasibility of burning low-Btugas in combustion turbines

has been demonstrated by several manufacturers; however, there

are no machines commerCially available which can burn low-Btu

gas: SUDstantial modifications must be made to existing

machines before this gas can be accomodated. The major

problems are associated with the fact that increased volumes

of the gas must be passed through the machines. Also, sinc e

the combust i-on turbine power plant must be located at the same

site as the gas ification pl ant, the two must operate

simultaneously. This type of operation is not suitable for

peaking duty plants. Instead, it lends itself much more

readily to base loaded plants, such as the combustion turbine

combined cycle or cogeneration plant.

Medium-Btu Gas:

~ledium-Btu gas can be produced by a variety of gasification

processes, including fixed be.d, fluidized bed, and entrained

flow gasifiers. Because of t ts increased heating value of

200-500 Btu/scf, medium-Btu gas has several distinct

advantages over low-Btu gas: first .of all, it can he burned

in exi sti n9 combustion turb ines without substantial

modifications.

Like many other synthetic fuel s, medium-Btu gas can be

produced with low sulfur content and little fuel bound

nitrogen. This also makes it readily suitable asa combustion

turbine fuel, since corrosion and exhaust emission problems

are. minimized.

Methanol:

~tethanol is a 1iquid synthetic fuel that may be derived not

only fron coal, but also from tar sands, 011 shale, and

biomass. It is suitable ase combustion turbine fuel, with

only a minimum of modifications to eXisting hardware required.

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From anemi.ssions standpotnt , methanol has several advantages

over petroleum based fuels. Methanol contains virtually no

nitrogen and no sulfur. Further, since methanol has a

theoretical flame tanperature approximately 300°F below that

of distillate oil, thermally produced NOx emissions areSUbstantially reduced. Carbon monoxide (CO) emissions are

increased slightly, but they are still comparable to

distal late CO emissions, especially when water injection is

required for distallate oil NOx emission reduction.

2. Fuel Transportation System

Requirements for a fuel transportation system depend on the

ease of storing fuel on-site. In using natural gas asa fuel,

storage is not required as long as an adequate ~~s supply is

readily available through local distribution. Distallate 0; 1

fSnorma lly stored on site and the amount of storage is

generally -"; function ofavai 1abi 1tty, Both storage and

transportation of low-Btu gas is impractical, requiring the

comubst ton turbine power plant to be located adjacent to the

gClsification. Medium-Btu gas can be transported economically

vi a pipeline to distances up to 100 miles. This removes the

limit.ation of locating the combustion turbines at the

gasification plant, and in fact, several power plants may be

served by a single gasi.fication plant. Like other liqUid

fuels, methane 1 may be stored on site. However, it is

'somewhat more volatile than distillate oil, and special

handling precautions are required.

D. Technical Considerations

Combustion turbine powerpl ants have traditionally been less

efficient than conventional fossil-fired generating stations.

This trend is changing, however, due to recent advances in

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combustion turb tne technology. Improvements in blade

metallurgy and cool ing t and improvements tn combustor

efficiency have been instrumental in increasing combustion

turbine output and improving eff tct ency,

The relationship among plant s tze, heat rate., and efficiency

of converting fuel to electricity is presented in Table 2.

The majority of the energy entering a combustion turbine as

fuel 1S lost in the form of exhaust gas heat. (Only minor

mechanical losses are encountered in the turbine/generator

machinery itself). For this reason alternative cycles have

been developed which utilize a portion of this exhaust gas

neat to improve efficiency. Combined cycle and cogeneration,

which are discussed in c'etail in separate technology profiles,

are two examples. A regener'ative cycle is another example.

In the regenerative cycle, air leaving the compressor section

is channeled throuqh enatr to air heat exchanger located in

the turbine exhaust. The energy thus absorbed by the

combustion air decreases the requirement for fuel and can

increase the c rmbust ton turbine efficiency ..

Combustion turbine is a flexible technology that can adjust to

both short term changes in daily and seasonal loads and to

long.....term changes in demand. Since combustion turbines can be

brought on 1ine quickiy from a cold start, they have an

excellent response time to changes in load. In the long t erm,

combustIon turbines can be adapted to an increased demand

through the addition or a waste heat recovery boiler,

converting the combustion turbine to a combined cycle sytem.

Small systems «100 MW) are common for combustion turbine

operations, allowing for incremental adjustments toa change

in demand.

8

* Lower heating value. For natural gas theLHV is 910 Btu/ft3 and the

higher heating value is 1024 Btu/ft3.

..

CONVERSION EFFICIENCY OF COMBUST ION TURBINES

AS A FUNCTION OF PLANT SIZ E

9

TABLE 2

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Heat Rate. Conversion Efficiency(Btu/kWh) . (Percent)

10,000 -11,000 (LHV)* 34

12,000 - 14,000 (LHV)* 30

Plant Size(kW)

50 ..;. 20,000

20,000 - 100,000

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A mtrrimum economical plant size for combustion turbines is 60

MW, which would serve approximately 17,000 households. Due to

the 1arge number of households served by one power pl ant,indjvidual consumer control is not possible. Combustion

turbines are reliable since they are available to meet demand" approximately 88 percent of the time.

E. Appl icationsof the Technology

1. Potential Contribution To Meeting Energy Requirements of

the RatIbel t Region

Due to the wide scale variation in unit sizes and the

fleXibility of adding a combined cycle; combustion turbines

are capable of meeting energy r-equir-ements in the Railbelt

region. Sites adjacent to the railroad or gas or pipelines

maybe suitable, depending on transmission line requiranents

and~istance to the load center. Potential sites are

indicated in Fi gure 2.

2. Type of Energy[A~mand Serviced

Combustion turbines are suitable to provide peaking and

emergency power generation. This is due in part to their

ab t 1 i ty to oper ate ina cyc l tc (on-off) mode, though perhaps

more importantly, due to their relative inefficiency compared

to conventional fossil-fired generating stations. One

exception to this rul e is low-Btu gas-fired combustion

turbtnes , which is better suited to provide base loading.

3. Complementary Technologies

Combustion turbines can complement cogeneration and combined

cycle technologies.

10

III. Project Economics

1I" Commercial Maturity/Statu s

Because of their simplicity and because of the absence of a steam

cycle, combustion turbine powerplCints are capable of unattended

operation. They can be sta.rted and stopped remotely from a centra1

dispatch station as required. Al though they are capable of cycl tc

duty, their reliability is better \r~hen continuous operation is

required.

As with any other facility, there is some economy of scale

associ atad with a combustion turl ioe powerpl ant. Installed

capital costs are presented "in Table 3. Virtually all of the

capital expenditures are for package equipment. Unlike steam

systems, field erection costs are minimal.

Capital Costs

... Combustion turbine powerplants are generally regarded as

having the lowest capital cost per kilowatt of any current

technology. Al so, due to the brief .construction tirres

involved, often one year or less, combustion turbine

construction costs are minimal.

A.

. .Tnecombusti on turbine is a proven technology which has been

utilized for commercial power generation for nearly two decades.

Since the early 19605, over 50,000 MW of combustion turbine

generating capacity have been tnstalled in the U.S. alone. This

represents approximately 8 percent of the total generating capacity

of this country. Due to their' low capital costs and short

construction times~ combustion turbine powerplants becameespecially popular during the late 1960s and early 1970s, when

utilities began facing critical generating shortages. Thepopularity has declined during the past five years with the advent

of increased fuel prices and limited loadgro\'/th.

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50 - 100

50 and under

TABLE 3

SUMMARY OF COMBUST"ION TURBINE PROJECT ECONOMICS(1980 DOLLARS)

Installed Equipment

($/ kW)

350

450

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Since no water is used i ngenerating power from combustion

1 turbines, there are no associated impacts on water resource s..

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PUblished 0 and Mcosts :.for combustion turbines generally

average around 4..5 mill s/kWh (see Iebl e 3). However, it

should be recognized that o and Mcosts vary drastically and

can often be m; sleading. Eve.n with identical combust ion,

turbines may report significantly different 0 and Mcosts.

One reason for thi sis bee ause maintenance costs are more

directly associated with operating practices than with

"equipment. For example, cyclic duty is much more demanding

than continuous operation. Extended operation at peak load

rating and premature loading without a proper warm-up period

can drastically reduce mach ine life. Improper fuel selection

and inlet air contamination can also have detrimental

effects. Al so, maintenance practices differ significantly

among utilities. Some utilities rely heavily on preventative

maintenance, wht Ie others only perform maintenance as

necessary.. In addition, the methods of recording a andM

costs are not uniform, and differences in reported costs may

result purely from accounting practices.

A. Water Resources

D. Operation and Maintenance Costs

c. Fuel Transportation Costs - to be provided by Battelle

B. Fue 1 Costs - to be provided by Battell e

IV. Environmental Impacts

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B. Air Resources

The primary emissions from a combustion turbine power plant

are SOx, NOx, CO, unburned hydrocarbons, andparticulates. EaCh of these contaminants can be controIl ed

depending upon local siting restrictions.

SOx and part icua1te emi ss ions are high ly dependent upon therespective sulfur and ash content of the fuel. Thus, proper

fuel selection can eliminate these pr-ob Iems , NOx production

is somewhat dependent on fuel bound nitrogen, but it is also a

function of combt ror flame temperature. By injecting water[~,

or steam into th'~ combustor, flame temperatures ~(Q-::nowered.

and thermal NOx emissions are reduced. CO and unburnedhydrocarbons emissions are dependent upon the effectivenssof

the combustion process. These emissions can be reduced by

proper fuel selection,. proper combustor and fuel nozzle

deSign, and proper ~perating techniques.

1. Terrestr ia1

Combustion turbine power plants generall y have re1at i vely

small land area requirements unless they are fueled by

distillate oil or certain types of synfuels Which require

onsite storage. Distillate oil may also require land for ash

and scrubber sludge (if high-sulfur oil is used) disposal. In

addition to direct habitat loss from the land requirements,

combust i on turbine plants c an impact terrestr i al biota through

gaseous and particulate emissions.S02 emissions probably

have the greatest· potential for impact s; however, this

potential is highly dependent on fuel type. Distillate oil ....

fired plants produce the highest level of S02 emissions

while naturalga.s-fired plants produce almost none.

14

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.2. Aquatic

Due to the absence of- a cool ing water cycle in combust; on

turbines, there would be no impacts on aquatic biota

associated\'Iith combustion turbines.

Aesthetic Intrusiveness .

Noise emissions resulting from the operation of a combustion

turbine power plant may present a significant local

environmental impact. Since noise levels assoctated with

plant operation attenuate with distance, no-ise has a more

site-speCi~rather than area-specific influence in siting

considerations. The problem of noise emissions depends on the

scale of the plant, nearby populations, and surrounding land

useS which may contribute to cumulative effects. The noise

impacts may generally be constrained b;! the use of extensive

muffling on the combustion turbine. The mufflers will result

in added costs and loweretficiency, but;heir appl teat-ion may

be varied over a Wide scale, depending 0;1 the amount of noise

reduction required.

Non-Renewable Resources

Distillate oil, natural gas, and synfuels (except f or methanol

produced from biomass) are all non-renewable resources. The

gradual depletion of these resources is affecting the

economics of utilizing such fuels. The long-term costs of

generating power from non-renewable fue.ls is less stable than ~

technologies which do not utilize fuel. Sharp increases in

the price of e·lectricity that may result from the use of

non-renewabl efuels are beyond the consumers I control.

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1M powerpJal1t- and 1ndustria1 Fue1 use Act of 1978 essent ta11 y

prohibit.s the use of gas and oil for electric power generationb.)lu

ewfacilities except under very restricted circumstances.

Anyone of s.everal exemptions maybe obtained. arising mainlyfrom cost • fuel avail abil i ty. anvironmenta1 considerati ons , or

operational requirements. These exemptions. except for theuse asa peak load facility. are involved and difficult toobtain. The regulations may. in fact. completely preclude the

use of combustion turbineS for non-peaking facilities exceptwhere eventua.l conversi(,n to synthetiC fuels. includiTl9 coal-

derived fuels, is assumed.

Health and Safety

Workers engaged in combustion turbine construction andoperation maY face a variety of health and safety hazards.Many of these are cOlll1l0n to a11 foss il energY t echne

1ogies.

Health and safety hazards coul d result from fUgitive air

en1issions. contact with harmful materiah. mechanicalfailures. accidental fires and other risks associated withnormal plant operation and maintenance such as noise. heat,

vibrations, and falls.

Air emissions from operation of the combustion turbine plantmay have a health impact. on nearby populations. Variables

affecting air emissions include plant size. operationshcedule. and th e sulfur content of the fue1. Lower grade.middle distinate fuels and Synthetic fuels derived from coal

have a relatively higher sulfur content .

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Socioeconomic Impacts

.A. Land Use

The construcrton and operation of a combustion turbine power

plant shou id have minimal land use impacts if the site is

compatible with prescribed land use. Land requirements are

minimal ;n comparison to other generating technologies. Land

use areas which should be avoided ;ncluderecreation areas,

wetlands$ coastal areas, mountainouS regions, and population

centers.

B. Labor Force and Employment

Combustion turbines typically are fabricated in shop at a

manufacturing firm outside of Alaska and shipped north by rail

or barge. Construction periods are relatively short because

the pl ants are erected primarily from components which are

manufactured and assembled off-site. As a result, few workers

woulo be required for a short time to assemble the plant. The

plant could be operated by remote control, eliminating

personnel reqUirements. Impacts on the local labor force

would therefore.be negligible.

c. Flow of Capital.&Rd 0 and Mand Fuel Expenditures',,,..l.,{ ~, \p., .~. (" ~.,...... _ . I -- • - • I ~ "'.

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The installation of a combustion turbine power plant will have

little effect on the stimulation of the regional economy in

terms of expenditures on capital, and operation and

maintenance. A flo'(/of fuel expenditures into the region,

however, may help to stimulate the economy. For example,a

lOOMW based load combustion turbine plane operating full time

ata 65 percent load factor .will require 1.5 x 106 bbllyear.<:)"P t)' t,