REPORT ON GEOTHERMAL POWER PLANT COST AND COMPARATtVE COST OF GEOTHERMAL At!D COAL FIRED STEAM POWER PLANTS. Prepared for

(1)

. .

Y

REPORT ON

GEOTHERMAL POWER PLANT COST AND

COMPARATtVE COST OF

GEOTHERMAL At!D COAL F I R E D STEAM POWER PLANTS

Prepared for

UTAH POWER AND L I G H T COMPANY

Y

(2)

DISCLAIMER

(3)

DISCLAIMER

(4)

...

4

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TABLE OF CONTENTS

.

I

tern Page

-

Sect ion I ,- 1.0 INTRODUCTION 1.1 Purpose 1.2 Scope

1.3

Format and Parameters

1.4

Two Unit Installations

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1-1 1-1 1-1 1-1

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2.0 2- 1 .1 Geothermal Power Plant Criteria

2.2 Geothermal Power Plant Cost Estimate 2-1 ,

2.3

2-2 2.4

2-2

2.5 Plant Capacity Factor 2-3

2.6 Appendix lnformation 2-3

Geothermal Power Plant Operating and Maintenance Cost Comparisons, Geothermal and Coal Fired

Requirements Power Plants

3.0

GEOTHERMAL POWER

PLANT

CRITERIA

3-

1

3.1

Weather

3.2 Geothermal Well Data

3-

1

3.3

Power Cycle

3-3

3.4

Slte Preparation and Building Construction

3-4

.

3-5

3-7

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3.5

Mechanical Design

3.6

Electrical Design.

Environmental Protection Considerations 3-10

Instrumentation a

3-1

1

4.0

GEOTHERMAL

POWER PLANT COST ESTIMATE

4.1

Building

4 .

2 Mechan 1 ca 1

4.3

Electrical 4- 1 4-2 4-2

4-3

1 4-4

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5.0

5-

1

5-

1

5.3

Expected Plant 5-2

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6.0

6-

1

6-

1 6.2 Coal Plant Costs by Accounts

6.3

Cost Comparisons, Goethermal and Coal Fired Power

. Plants

6-1

.

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TABLE

OF CONTENTS (Cont'd)

Appendix A

A- 1 Steam Gathering and Waste Water Reinjection Systems - Description

A-2 A-3

A-4 Equipment Quotat ions

Steam Gathering and Water Reinjection Systems Cost Estimate Gathering and Reinjection System Economics

&pendix C

Two Unit Estimates and Comparison Two Unit Geothermal Plant Estimate

Two Unit Coal Fired Plant Estimate

Cost Comparison, Geothermal vs Coal Fired

c-

1

Introduction c-2

c-3

c-4

c-5

Cash Flow Appendix

D

Back Up Information, Cash

Flow

and Interest During Construction

(6)

Drawing No. Lil A-02- 102 8-02- 10 1 B-04-101

A-08-

1 0 1 €-Of-

1

0 1 B-80-101 B-80- 102

B-80.-

103 8-80- 104 .B-80-105 Table No.

4-

1 4-2 6-

1

6-2 C- 1 c-2

c-3

c-4

i

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I Figure

No.

6.4-1

6.4.-2

INDEX

OF DRAWINGS 1 Description

Noncondensable Gas Purification "S tretf ord Process''

Power Plant Process Flow Diagram

4

-Plot Plan

Power Single Line Diagram

Page

3-15

3-1

4 3-16

3-2 1 Construction and Engineering Schedule

4-1

1

Ground and Mezzanine Floor Plan

3-17

Operating Floor Plan

3-18

Side Elevation

3-19

Cross Sect ion ' 3-20

Ground and Operating Floor Plans, 2 Units _APP.

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INDEX OF

TABLES Description

Summary

-

fmery #l and 62 Estimate

-

May

1977

Geothermal vs Coal Cost Estimate Comparison

(Grossf Geothermal Power Plant

rn Power Plant

brass

f

Geotherma 1

Engineering E; Construction Schedule for

400 HW Coal Fired Plant

Engineering E; Construction Schedule for

(7)

- -

1.0 INTRODUCTION

iil

ngineering was reque (gross) geothermal p

d to prepare a cost estimate for r plant at Roosevel t Hot Springs power plant cost in ollars per net kilowatt is to

be compared th that for Utah ower and Light Company's Emery No.

1

400

M

et) coal-f ired eam power plant now under con- s t ruct ion.

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the Phillips Petroleum Company's discovery. The

1.1 Purpose

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. i i 1.2

This report is to be used by Utah Power and Light Company In making studies of geothermal plants. The dollars per kilowatt comparison between ermal plant and a UP &

L

coal-fired plan s to be developed. Geothermal gathering

system costs an eturn to owner are to be developed for in- format ion.

I

Scope

Prepare a detailed conceptual cost estimate for a

55 MW

gross

(32

MW

net) geothermal power plant using Phil 1 ips Petroleum Company's resource characteristics.

Prepare preliminary pr cess flow diagram to size major equipment Letter quotations on major items are included

Provlde an estimate of cash ftow during the engineering and con- struction period.

t

. f

ey;

er letter quotations stating price, delivery, and nt.

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1.3

Format and Parameters

The cost e s t i m a t e detail i s to follow U

P

S L's format for Emery No. 1: Man-hours, Material and Equipment, and Direct Labor costs.

u

P &

L ' s mos e to be used in the geotherml

ntal costs are to be shown

ey could sup- The resourte are those in ROGERS previous report 'for

'UP &

L

"Evaluation of Geothermal Fluids from We1 1 No.

54-3" December

1975.

t

1.4

n i t Jnstallatlons

conomy inherent in constructing twofunits at one plant site, thus

utilizing

certain c m n facilities, cost esti- mates and comparisons are provided for a 2X 52

MW

geothe-mal powei plant and a 2X 400

MW

coal fired plant.

(8)

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2.0 SUMMARY

The information in this report is to aid Utah Power and Light in their economic studies related to geothermal electric power gene- ration from the Roosevelt Hot Sprtngs resource. The report in- cludes development of the geothermal plant design basts, power plant cycle, process flow diagram, and the electrical power single l i n e diagram on which the estimated capital cost is based. The coal plant data was furnished by Utah Power and Light for its

Emery Plant, Unit No. 1, being constructed and due for operation

in

1978.

L

1

2. i

, - urnished the resource data at

downhole conditions with enthalpy of

493.3

Btu per pound.

power plant destgn which maximizes the energy extraction per .

pound of resource i s the double flash system.

tlons'are favorable to the double flashed system which utilizes a turbine with two entry steam pressures.

Informatton available to date, indicates that the noncondensable gas content o f the flashed steam has a low hydrogen sulfid, e con-

lant incorporates a minimum amount of hydrogen sulfide Added costs are specified in Section

3.3

i f hydrogen

The Resource condi-

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ulfide abatement i s necessary.

ant as conce l l y designed uses 3,926,600 pounds per hour available after [down hole basis) of the resource.

the production fluids are to be re rated 55,000 kW gross with an estima station power i s subtracted.

chanical and electrical design criteria are discussed by equipment i'tems and overall characteristics.

n should be noted concerning equipment and material con- er hour, of

plant is

Special at- struction.

units, Is designed on a unit basis.

The plant, In the future to hold a total of two The electrical single line

d selected accordingly. is assumed always avail-

small diesel generator

2.2

ection

4.

It

Is

istration area.

It has been general practice to include only two

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The bullding i s laid out to accommodate a future additional 52 MW unit.

units

per plant to minimize trmsporting the geothermal fluids and steam great distances.

one plant the geothermal wells would probably be several miles from the power plant.

I f more units were installed in

(9)

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tah Power and Light's subaccounts and the Federal Power Commission ccounts were utilize n detailing the plant cost estimate. Major

equipment cost and de Utah.

Power. and Light's Emery No. 1 power plant labor rates were used in. the cost estimate. The total construction cost including substa- tlon 1s estimated to be $23,640,400 or

455

dollars per net ktlo- watt.

ery time were solicited from vendors-

The engineering and construction time required is estimated to be

34

months based on similar plants. Section

4.5

contains a schedule for engineering and construction of a 52 MU geothermal power plant.

This time excludes permit and utility comission times, if required, before engineering.

accounts in Section

4.4.

Geothermal Power Plant Operating and Maintenance Requirements The operation staffing and 'maintenance requirements are direct in- puts to developing cost of energy sold.

staffing requirements for normal operation and maintenance. plant is planned to be base loaded and operate three shifts per day.

tepor t

.

+

The plant is schedule

year. The maintenance crew is listed in Section 5.2.

The d ailed estimate is provided by the sub-

This report discusses The .

Operation and maintenance expenses are not shown in this

or maintenance approximately two weeks per

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The Emery comparison plant because the labor costs are the No.

1

coal fired steam power plant was selected to most recent. be the summary by FPC account category is included in Section 6.2.

labor rates were used in t

Emery costs are from the

M

A These geothermal plant cost estimate. The

1977

monthly cost forecast.

geothermal power p l a n t and t h e

ollow. Both single unit and tional detail and backup for

e found in Tables

6-1,

Geothermal Coal Fired Tota

1

Cost [substation excluded) $22,482,700 $252,000,000

Dollar per Net Kilowatt 432 -630

Net Capacity 52,000 kW 400,000 kU

Engineering E Constructi

34

months 60 months

(10)

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-_TWO Unit Plants

Geotherma 1 Item

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Total Cost Csubstation excluded1 $39,142,000

Net Capacity 104,000 kW

Engineering and Construction Time 40 months

Base Load Yes

Dollars per Net Kilowatt .

376

2.5 Coal Fired $449,933,000 562 800,000 kW Yes

--

Plant Capacity Factor

paclty factor i s estimated to be

85%.

I

*.

I Four appendices are included with the report. The first (Appendix

A) develops cost and investment return ranges for the geothermal resource production and reinject ion system.

B)

cont,ains letters from manufacturers relating to cost and delivery

of the major equipment pieces in the geothermal power plant.

geothermal cost estimate reflects these manufacturers' data.

' third (Appendix

C)

gives estimated costs for two unit geothermal and

coal fired plants. The fourth (Appendix D) includes back up informa-

t i o n for calculations of cash flow and IDC.

The second (Appendix The' The

b

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3.9

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e

-GEOTHERMAL POWER PLANT DESJGN CRITERIA

This Section presents the geothermal power plant design criteria and the operating conditions the design i s based on. Main areas

of discusslon presented here are as follows:

1)

Weather conditions

21 Geothermal well data

3)

Power cycle

4)

5 )

Site preparation and building constuction Mechan

I

ca 1 des i g n

rotection considerations Weather Data

Basis for design for cooling tower and ventilating and air con- ditioning design:

Summer: 96°F Dry Bulb 67°F Wet Bulb Winter: 920°F Dry Bulb

Haximum Wind Velocity: 60 mph Design wind loading:

I

Below 30 feet

Above 30 and Below 50 feet Above 50 and Below 100 feet

-

15

lbs. per square foot

-

20 lbs. per square foot

-

25 lbs. per square foot Geothermal Well Data \

Downhole 1 iqu4d temperature: Downhole l i q u i d enthalpy:

Noncondensable gas composition:

Gas

-

0.02 Hydrogen 0 -

75

He1 ium Net hane 0.004 Nitrogen

0.8

Carbon Dioxide

93.34

Carbon Monoxide e10 PPm

0.1 Argon

Noncondensable gas quantlt): 2% by weight

in

the fyrst

(12)

- -

bd Chemical Content o f Resource per Lab Report 0323-75

PPM

Boron,

B

31 -

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Calcium, Ca Magnesium, Mg b 10 0.01 Potassium, K 470 iu Sodium, Na 2,200 tu .

145 .

Chloride,

CL

.

3,900

k Nitrate, ~ 0 3 ) Nitrite, NO21 '

75.1

520 bd . Silica, Si02 Ir nate, CO ) bonate, kO3)

173

ki PH

7.58

.

Y Gas Composition o f Resoure per Well Data, Handwritten-Well

54-3

Sample #4 Gas From Wellhead 9/17/75

-

Temperature, "F/Case Pressure, p s i a

Noncondensable Gas % W t . o f 1st Entry Steam

2nd Entry

-

Temperature, "F/Case Pressure, p s i a

Hain 'Condenser I n l e t , Inches Hg Absolute Turbine Steam I n l e t Conditions

. Pressu

Temperature

Steam Enthalpy, Btu/lb. I n l e t a t Flange l s t / 2 n d Turbine Drop l s t / 2 n d

Turbine Exhaust S a t u r a t i o n Temperature

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. Condenser Type: Condensing Water Flow 1b.rVlr. GPM (60°F) Temperature "F/Pressure, p s i g f

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Cold Return \

e a t Transfer Duty, Btu/hr. ( m i l 1 ion)

a t Generator Terminals Cooling Water C i r c u l a t i o n Pumps

Cooling Tower Fans

Mlscellaneous A u x i l i a r y Loads

TOTAL POWER PLANT AUXILIARY POWER

DESIGN NET GENERATION

(14)

- -

3.4

Site Preparation and Building Construction

This Section describes the site and power plant building aspects of the project.

3.4.1

Site Preparation

Drawing B-04-101, included at the end of this Section, indicates the layout

of

the power plant site relative to the power plant building, cooling tower and substation.

of these three components for the additional Second 52 MW unit are also shown.

The future development The substation is shown fully entlosed by a e and gates. The power plant building shows the cess door central to the turbine'units in the ent. Front access to the administration area is shown in relationship to a proposed parking lot, landscaping and paved area, with direct roadway access.

For

the initial phase (one 52 MW unit), the drawing shows the main transformer connected via a bus duct to the

13.8

kV switch- gear inside the power plant, and connected to the high voltage substation bus having three oil circuit breakers and associated disconnect switches; the first terminal point i s for the main step-up transformer; 2nd and 3rd terminal points are for the

138

kV 1 ine takeoffs. Future arrangement provides for expansion of the ring bus to five

(5)

terminal points, i. e., two points for step-up transformers, and three points for

138

kV line take-

offs.

3.4.2 Building Design Criteria

Structural Frame Steel columns and bracing Mezzanine Floor and Operating floor

Roof

Truss Steel, long-span

Steel frame, with concrete filled steel decking

r

I Exterior Wal Is Steel "Gal bestos" panels

insulated, with inside liner. Exterior and

interior faces pre-finished. (lrU" Value 0.13).

Steel "Galbestos panels, as

above. ,

3,000 psi concrete 4,000 ps f concrete

Zone

3 -

Importance Factor

1.5

Zone 20

i

, _

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,,Roof i ng

Foundation, Ground Floor Slab Turbine Pedestal

Selsrntc Design Wind Load

Assumed Live Loads

. Operating Floor 125 psf

Reinforcing Steel . ASTM A-615, 60,000 psi

. Structrual Steel ASTM

A-36

Assumed Soi 1 Pressure 3,000 p s f

Roof 20 psf (snow load

-

202

Mezzanine

75

psf

Third

Floors

75

psf

Administrative Bay

-

Second and

(15)

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3.4.3

' Building Types Considered:

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a) Poured in place reinforced concrete frame, exterior walls .and floors (mezzanine and operating floors); a steel roof

framing system with steel roof siding.

b) A structural steel frame with steel bracing and steel wall siding; structural steel floor framing (mezzanine and

operating floors) with concrete fill steel decking, a steel roof framing system with steel roof siding.

[Reinforced concrete foundations, ground floor slab and tur- uld be common to both types a and b).

selected on the basis of suitability for archi- . tectural requirements and economy. The dimensions indi- cated for the power plant building provide for optimum operating efficiency in both the vertical and horizonal directions.

Long span trusses over the operating floor provide the clear span required for the flexibility of overall bridge

ors for the performance of the operations are included to facilitate a logical flow to and from the building. The main service access to the power plant will be via a large rolling steel door, motor operated, planned central to the

-

two 52 MW units (2nd 52 MW unit-future) and contiguous with the machine shop.

, The main control room will be located on the third level of the administrative bay, level with the operating floor. By means of an observation window, the control room will have

the visual control for the entire operating floor area. Reference sketches of floor plans, building side elevation and

ss section are shown on Drawing Nos. 8-80-101, 102, 103 and

L

3.4.4 Li

t the end of Section

3.

1

b

3.5

3-50 1

equipment are shown on the process

t the plant, plot limit on the econd stage separators and b

f l o w diagram 8-02-101. The power plant

from

the mechanical 'viewpoint is considered to start

downstream side of the first and

finish at the coollng tower and vent silencer discharges.

(16)

4

-The first and second separators and the reinjection pumps are thering and reinjection system, and ower plant components.

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Main Turbine

1 '

. 3.5.2

' b

The main turbine is a double flow, mixed pressure condensing turbine. The high pressure stage inlet pressure is approxi- mately 110 psia and the low pressure stage inlet pressure is approximately 25 p a with a rated gross output f r o m the generator of 55 MW The turbine output shaft is coupled directly to the ge rator shaft. The turbine exhausts into

condenser at e back pressure of

89

m m hg.

(3.5

inches) absolute. The steam flow is controlled on the high pressure and low pressure inlet lines by means of control valves

uated through the hydraulic governor system on the turbine.

The material of construction of the turbine is as follows: a) Top and bottom outer shells are cast steel

b) Steam path is stainless steel

c) Blades and rotor are stainless steel.

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3.5.3

Condenser

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The main condenser i s located immediately below the main turbine and accepts and condenses steam discharged from the turbine primary and secondary exhaust stages. The coneenser is a direct contact spray condenser in which exhaust steam from the turbine i s directly mixed with and condensed by the cooling water from the cooling towers. The condensate then becomes part of the make-up cooling water in the cooling tower. The condenser is constructed of a carbon steel outer shell clad with

316L

stainless steel for the

inner shell.

The condenser i s operated at a vacuum o f

89

mm (3.5 inches1 Hg

which is produced by the steam jet ejector system. The condensate i s removed from the condenser by means of the hot well pumps and pumped directly to ere Noncondensabte gases are removed from a spe sectlon ? n the condenser by means of a two stage steam jet ejector.

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3.5.4

Hot Well Pumps

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Each hot well pump i s

pumps are located adjacent to the condenser and are the "canned" type vertical contrifugal pumps,

low net positive suction head available from the condenser.

pump is sited to handle

55%

of the total flow though the. condenser.

The flow

to

the cooling tower from the condenser via' the hot, wells pumps i s controlled by means of flow control valves which are

integrated with the water level control system on the condenser. ted 1,000 horsepower. The hot well

This type is used because of Each

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3-6

(17)

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3.5.5

Cooling Towers

H:

The c o o l i n g tower i s a mechanical induced d r a f t type having s i n g l e speed reversing e l e c t r i c motor d r i v e n fans.

fans have t h e reversing c a p a b i l i t y t o insure proper operation d u r i n g w i n t e r conditions.

through t h e towers thereby inducing t h e d r a f t .

The c o o l i n g tower f u n c t i o n i s t o cool t h e water r e t u r n i n g from

t h e condensers v i a the h o t w e l l pumps, and-provide it c o l d water

d a l l water using equip-

ment as w e l l as a t e r t o the p l a n t f i r e

The c o o l i n g tower

The fans a r e operated t o d r a w * a i r

.

storage s u f f i c i e n t

t h e . cool i ng tower bas i n

The water i s drawn i n t o

. (cold w e l l ) v i a l a r g e diameter piping.

the condenser under t h e e f f e c t o f a vacuum produced by the e j e c t o r sys tem.

The c o o l i n g tower i s konstructed mainly from wooden members

forming the superstructure and louver sides.

c e l l s a r e separated by f i r e proof s i d i n g which i s a l s o used

t o cover the o u t s i d e un-louvered areas.

The i n d i v i d u a l P-

3.5-

6 P i p i n g Systems

Li

The p i p i n g i s b a s i c a l l t h e o t h e r water. The s

carbon s t e e l p i p e and the

from s t a i n l e s s s t e e l pipe.

n o t e x h i b i t the same tendencies as geothermal water t o cause

c o r r o s i o n a t an accelerated rate. . -

separated i n t o two areas, one steam and am system p i p i n g i s constructed from

t e r system p i p i n g i s constructed

The d i s t i n c t i o n i s made because of

Geother-1 steam does

. t h e c o r r o s i v e nature o f geothermal water.

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3.6 E l e c t r i cat Des i gn'

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3.6.1 'Genera 1 1 3. a t i e c t r i c a i uesign Y 3.6.1 'Genera 1 1

proposed Utah Power and

n "Power Single L i n e

ev. A, included a t t h e end of

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i t h a gross output o f 55

li

b l Generator a i r c i r c u i t breaker switchgear w i t h c i r c u i t

breakers r a t e d 13.8 kV and 1,000 MVA i n t e r r u p t i n g capacity.

(18)

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4

-step-up transformer from

13.8

kV to

138

kV served from the

.8

kV generator swi tshgear by 3000A nonsegregated enclosed s duct and connected on the 1 ine sfde to the

138

kV switch-

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yard ring bus.

d) el

Three

138

kV oil circuit breakers in a ring bus arrangement.

A

13.8

kV to

4.16 kV

transformer and associated draw-out motor

starters to serve two I000 H.

P.

hot well pumps and space for

V bus tie circuit breaker.

0 volt transformer and associated swi tchgear rbine-generator auxiliaries, cooling tower fans

lding service loads, including space for a future

480

V bus tie circuit breaker.

An

auxiliary diesel generator rated 200 kW at 0.8 powe'r factor to serve emergency lighting and other essential loads under emergency conditions.

9)

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3.6.2

. Main Turbine Generator

The generator supplied with the steam turbine will be totally en- closed for recirculating hydrogen cooling with hydrogen-to-water heat exchangers and brushless excitation.

watts gross,

61.1

MVA continuous at 60 Hertz and

13.8

kV.

It will be rated

55

mega-

. 3

Generator Swi tchgear

The generator switchgear will be rated

13.8

kV with 1000 MVA inter- rupting capacity and will be of the metal-clad, drawout type, for location Indoors, with a generator circuit breaker and two feeder circuit breakers to serve the

4.16

kV and

480

volt auxiliary trans-

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formers.

3.6.4

Step-up Transformer

The ste transformer will be located outdoors in the

138

kV be oil-f i

1

led rated 37.5/50/62.5

MVA, OA/FA/FA,

VA,

OA/FA/FA, at

65°C

rise, 13.8/138 kV, nsformer will be served from the 13.8 kV

ct. The trans- s. The transformer

1 ightning

tandard accessories for this class of transformer ipped with standard high voltage taps:

ormal, with a man

i

(19)

3-6-5

3.6.6

4

-Oil Circuit Breakers

-

138 KV

The three oil circuit breakers for the ring bus will be Fated

138

kV, 1200A, 5000

MVA

interrupting capacity, and will each be provided with two gang-operated air disconnect switches for cir- cuit breaker isolation.

Air Disconnect and Ground Switches

-

138

kV

In addition to the circuit breaker isolation air disconnect switches, each line will be provided with a gang-operated air disconnect

switch and ground switch, and a gang-operated air ground switch will be provided on the section o f the 138 kV ring bus which is connected to the step-up transformer. Air disconnect switches will be rated

138

kV, 1200A.

.

3-6.7

138 kV

Swl tchyard Arrangement

The ring bus arrangement of the

138

kV switchyard will facilitgte the addition of a fourth oil circuit breaker in the ring bus in the future when the second turbine generator and step-up transformer are instal led.

3.6.8

4.16

kV Transformer and Swi tchgear

I

The

4.16

kV transformer and associated swi tchgear wi 1 1 be located

indoors.

OA/FA,

at

55°C

rise and 2800/3500 kVA, OA/FA, at 65°C rise, 13.8/4.16 kV, 3-phase, 60 Hertz.

the metal-clad drawout type and will include a drawout motor starter to serve each o f the 1000 H.

P.

hot well pumps and space for a future

4.16

kV bus tie circuit breaker.

480

Volt Transformer and Swi tchgear

The 480 volt transformer and associated switchgear will be located indoors. The transformer will be silicon-filled rated 2500/3125 kVA, OA/FA, at

55°C

rise and 2800/3500 kVA,

OA/FA,

at 65°C rise,

13.8

kV/

The transformer wi 1 1 be si 1 icon-f i 1 led rated 2500/3125 kVA, The

4.16

kV switchgear will be of

3.609

rtz.

ype and wi,ll include an air circuit breaker to ree plant auxiliary building service motor con-

mps. symmetrical.

The 480 volt switchgear will be of the

trol centers

breaker.

Ai

uit breakers will have a minimum interrupting

pace for a future 480 volt bus tie circuit

3.6.10 Auxf 1 iary Diesel Generator The auxiliary diesel ge failure of normal power

loads.

tor will provide emergency power upon emergency lighting and other essential

(20)

a

-factor,

480

volts, 3-phase, 60 Hertz, and will supply power to vice motor control center.

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3.6.11

Plant Start-up'

3.6.12

h j .

The plant design is based on connection to two incoming lines on a

138

kV grid system.

can be started by energizing the

13.8

kV switchgear bus from the line through the step-up transformer. This permits operation of all turbine/generator auxiliaries and the hot well pumps, and when the generator is u p to speed and voltage, it can be synchronized

With both or either lirie in service, the plant

generator circuit breaker.

/generator to provide cold starting The added of the plant independent of the

138

kV Vines is 1,300 kW.

expense of approximately $7.00 per kW based on 52,000 kW net, or $364,000, does not seem to be justified economical l y with power available from two incoming lines.

Corrosion Protection

There is an inherent hydrogen sulfide atmosphere in geothermal power plants which i s corrosive to copper.

given to the protection of all electrical facilities. 6

Special attention must be Vulnerable

opper connections and contacts are to be tinned or plated with a rotective coating which will protect them against the harmful ef-

rogen sulfide. Since hydrogen sulfide does not aluminum bus, tubing and cable will be used for

. application above ground throughout the outdoor substation.

For added protection from the hydrogen sulfide atmosphere, switch- gear, motor control centers and main control boards will be located

ln charcoal filtered clean air pressurized rooms to prevent adverse

i

effects on electrical contacts.

3.7

c'

L

ii

Environmental Protection Considerations

Information available to date, indicates that the noncondensable gas content of the flash steam has a low content of hydrogen sul- f4de.

lfti,es for hydrogen sulfide abatement. tndicat

to requ

ments, the following plant design changes and equipment additions would be required:

On

this basis, plant design and costs include minimum faci- Should further Information gen sulfide content increasing to values high enough or abatement facilities based on air quality require-

L

a) Change main turbine condenser design from direct contact to surface type.

.

(21)

W

L.

- *

b) Change intercondenser design from direct contact to surface type. lntercondenser condensate to be separately collected and transferred to the'sulfur recovery system.

Add a Stretford type sulfer recovery unit to treat the exhaust gas from the turbine condenser vacuum system and the gas cool- ing and jet condensate.

c)

Drawing A-02-102, included et the end of this section, indicates the sulfur recovery equipment required by the installation of the "Stretford Process" noncondensable gas purification system. The increased cost for surface type heat exchangers for main steam condensing, gas cooling and intercondenser above that for a direct contact system is as follows:

Surface Condenser Installed Cost $ 800,000

Stretford Untt Installed Cost

(Including Paid Up Royalttes) $2,000,000 H2S Abatement Total Estimated

(22)

. .

- *

trol is supplemented by a bypass valve to return a portion of the discharge water from the hot well pump to the main condenser. bypass valve operates during conditlons of extreme low level in the condenser such as during plant start up.

The

I +

b

3.8.2.3 Condenser Pressure Control .

The pressure in the main condenser is regulated by a valve which controls the flow of cooling water to the sprays in the main con-

L

1 i:

L

Anti-Surge Control

Control is provided to admit ambient air to the suction side of duced load operation.

Lube Oil Warm Up System

Control i s provided to turn off the cooling water to the lube o i l heat exchanger to provide a fast warm u p of lube oil after a cold start.

.the noncondensable gas ejectors to prevent surging during re-

. .

1;

3.8.2.5

3.8.2.6 Compressed Air System

Compressed air is provided by two compressors.

pressors normally supplies instrument and control air and one compressor normally supplies utility air to the station.

One of the com-

The control air system.draws air from the charcoal filtered air

supply to the air conditioning system. provide air with a

-45°C

dewpoint.

through a filter-regulator at each point of use.

In the event of the failure of the control air compressor, manual

valves are provided so that air from the utility air compressor may be introduced to the control air system ahead o f the dryers.

A dryer is provided to Instrument air is provided

~

Y I

fire pump sys pressure switc

s maintalned by a jockey pump

In the event the pressure con- inues to drop with the jockey pump running, a second contact of the pressure switch will start the main fire pump and open the automatic discharge valve.

operate a third pressure switch contact to start the No. 2 main fire pump and open its dfscharge valve. As the pressure In the system i s restored, the pumps will be stopped in the reverse order.

I '

u .

A continued drop in pressure will

.

(23)

3.8,3

3.8.3.1

3.8.3.2

3.8.3.3

'

3,8.3.4

3.8.3.5

3.8.3.6

3.8.3.7

3.8.3.8

3.8.3.9

3.8.3.10

3.8.3.11

. . 4 -Alarms

Alarms are provided to the control room annunciator to alert the operator to imminent problems, The most important of these in- cl ude:

Main condenser low level Main condenser high pressure Main condenser low pressure

lntercondenser high pressure rcondenser high level Low f I re water pressure

Lube oil centrifuge breakover Low control air pressure Hotwell pump low flow alarm

erflow S u m p Level Control

oat switch i s provided in the sump of the cool- p the excess condensate to the blowdown area.

Air Compressor Cooling System Surge Tank

(24)

(25)

(26)

(27)

(28)

1-

I

(29)

(30)

t

REV

lj

DATE R E V I S I O N

DETAtLS

ENG. APPR.

(31)

UTAH

POWER & LIGHT 5 5 M W GEOTHERMAL PROJECT

I

JOB NO. S 74002-02 REV

Rogers

POWER -SINGLEA-

E DIAGRAM

.A-08-101-

A

P A G E - 3 - 2 1 __

(32)

. .

d

_ -

. .

id 4.0 GEOTHERMAL

POWER

PLANT COST ESTIMATE

_{The cost estimate for the proposed building represents}_a_design

of the following components:

A power plant building to house one 52 MW unit, with appropriate administration and ancillary services to effect a complete self-

I contained operation. The degree of administrative and ancillary

services included in the initial phase will be sufficient to serve a future second 52 MW unit.

The initial building, 158 feet X

78

feet, will consist of six bays at 22 feet,

8

inches each for a total dimension of

136

feet in the power plant proper, with a n additional bay of 22 feet,

8

inches to accommodate administrative and ancillary services, for an overall length of

158

feet.

, the power plant will be approximately

75

feet above the ground

floor.

The power plant will have three (3) floors, namely, ground floor,

* mezzanine f-loor, and operating floor, The vertical heights be-

tween the respective floors will be approximately

14

feet

-

0 The administrative and ancillary service areas comprising three

(3)

floors in a lower level connected structure will contain the following:

b

1?

Eave helght in , I

ii

b

inches.

(33)

4.1.1.3

Change and Locker Room

4.1.1.4

Electrical Shop

4.1.1.5

Instrument Shop

L

il

4.1.1.6

-Chemical Laboratory

4.1.1.7

General Office, including Mechanical

and Electrical Supervisors

Machine Shop with crane and parts

(will

occupy a n area in the power

t

4.1.1.8

storage,

plant, ground floor 1 eve1 )

L

i

i 4.2 400 sq. ft. 520 sq. ft. 500 sq. ft. 1,500 sq. ft.

A 50-ton'rfidge crane, operable throughout the power plant, wi 1 1 be mounted approximately

35

feet above the operating floor level. Nechanical

The estimate was prepared on the basis of construction man-hours, and equipment and material estimated costs.

h

4.2.1 The basis of the cost estimate for mechanical equipment and materials comes from two sources.

a) Prices quoted by manufacturers to a written summary

Id

Y specification.

b) Prices established by current or previous projects of the

lb

same nature and size.

4.2.2 The mechanical equipment duties shown on the Process Flow diagram

8-02-101, Rev. A, are the basis for the cost estimate. The equip-

ment items for which quotations were obtained are as follows: 1) Turbine Generator Package

3) Hot Well Pumps

4)

Cool ing Tower

5)

Main Bridge Crane

The installation manhours are based on a combination of (a)

previous actual manhours for this type o f project (b) Richardson's Estimating Data Book information and (c) in-house experience

in estimating manhours

in

similar type installations.

~ 2) Condensers

iu

4.2.3

b

t

**_4*3**

.

Flectrical , -*

4.3.1

Electrical Equipment Ratings

L

4-2

4.3.1

Electrical Equipment Ratings

(34)

i

I

4

-The Power Single Line Drawing A-08-101, Rev. A, shows the major electrical equipment elements and ratings.

based on the single line equipment and the electrical design

Electrical Equipment and Material Costs

Electrical equipment + criteria in Section

3.5.

4.3.2

1

I I

The electrical equipment and material costs in the estimate are cur- rent, June

1977.

-

L

4.3.3

Electrical Constructlon Man-hours

The electrical construction man-hours in the construction cost esti- mate are based, in general, on Richardson Engineering Services, Inc.

-

"General Construction Estimating Standards

-

Mechanical and Electrical"

-

1976-77

Edition.

lJ

1 t

ii

Labor man-hours not included in the above Estimating Standards are based on man-hours for similar work from experience on previous power plant installations.

4.4

Cost Estimate By Accounts

The geothermal power plant cost estimate is presented by Utah Power and Light's accounts and subaccounts. In preparing the estimate, a

major factor in its presentation was keeping it similar in format to

other

UP &

L power plant projects for ease in comparing costs.

The summary cost estimate for the 55 MU gross geothermal power plant is presented in Table

4-1

in this Section.

table is a detailed listing by Utah Power and Light accounts and subaccounts of the geothermal p\ant cost estimate details.

All

equipment and material purchases for the project are under Mate- r i a l and Equipment. The man-ho'urs are the estimated construction man-hours required. The labor rates used are those given i n the

UP &

L

January

1977

report on Emery No. 1 costs escalated to June

1977.

at the middle of a 40 month construction period per recommendation o f the

UP &

L

engineering department. the middle of construction was taken as October

1976

and therefore

7

months of escalation

(0.05264 at

8%

labor per year Utah Power and Light figure) i s ap- plied to the Emery rates to get those used in the geothermal esti-

The geothermal power plant total construction cost including substa- tlon i s estimated to be $23,640,400 or

$455

per net kilowatt.

L -

Succeeding the summary

These construction labor rates are assumed to be the average

r

d

mate, Table

4.1.

' >,

rd

4.5 Engineering-Construction Schedule

The engineering and construction schedule is graphically represented by Drawing E-07-101, Rev. A.

experience by Rogers in implementing geothermal power plant design, procurement of a1 1 major equipment, and construction management o f

the plant.

This schedule i s the resul-; o f past

(35)

i i -

i;

i

ii

C '

4.6

_ c

The schedule presumes the resource is sufficiently defined to be able to proceed with the plant design based on the resource characteristics and well locations. This schedule includes an allowance for bids for all major equipment to be requested and evaluated according to detail specifications. The construction

i s separated into mjor areas: site, civil/structural, mechani- cal, etc. to show the allowed times and major interrelation- ships. The longest delivery item, the Turbine-Generator package, Is the item which governs delivery and construction schedules. Delivery to the site i s quoted by manufacturer to be 20 months. With delivery time of the turbine-generator package being 20

months, the shortest design and construction schedule achievable Is

34

months. This schedule i s based upon the increased time of delivery schedules recently proposed by manufacturers of turbine- genera tor packages.

The engineering includes all design engineering of construction drawings inside the power plant boundary fence, procurement of all equipment and major construction contracts, and on-site super- vision by engineers as the construction progresses.

tion of the manufacturers' and construction personnel is maintained by the design engineering group.

Permits for building the power plant or acquirlng permits for site construction and transmission line rights-of-way have not been in- cluded in the schedule. The schedule represents only engineering, procurement and construction since the Stearns-Roger construction schedule, as provided by Utah Power and Light Company for the 400 MW coal fired plant, does not provide for acquisition of plant permits or transmission line rights-of-way. A comparison of the geothermal schedule with a coal plant schedule is included in Section

6.3.

Estimated Cash Flow

Close coordina-

An

estimated cash flow for the engineering and construction period, taken as 34 months, has been prepared at the request of UP & L (see

PCN

No. 21 of July

15,

1977),

and i s shown in Table 4-2. Back up information may be found in Appendix D.

(36)

‘.TABLE

4-1

29,800 4,300 SUMMARY

55 MW [GROSS) GEOTHERMAL POWER PLANT

COST ESTIMATE JUNE

1977

. Mater I a 1 s . . and

I‘

u

1.

Account

Number Description Equ i pmen t Labor Cost

31

1 Structures and Improvements $. 1,186,000 $ 597,400

1:

, 312 Boiler [Steam Piping Only) 171,000 92,400

-

314

Turbogenera tors

.7,85O,OOO

1,091,900

315

Accessory Electrical Equipment 740,000 198,900

( 1

316

. Miscellaneous Power Plant

353

~ C b s ta t ion Equ i pmen t

1;

_443,000 _258,500 ,738,000 255,200

-

Refund Taxes t Sub Totals $1 1,128,000 $2,493,400 Man-hours

I

12,700 17,600 9,900

147 ,

500 31Q Land $ 8,000

399

Contractor Overhead and

Profit 2,100,OQO

Plant Instal led $15,729,400

399 UP

d

L

Charges

.

475,000

399

Engineering 2,000,000

L

$ 1

1w

399

lnterest During Construction 2,352,500

Sub Total $20,556,900

L

Con t i ng ency

3 ,

083,5OO\i

I ,

TOTAL

CONSTRUCTION COST $23,640,400

P ’

k *

-

Power Plant Construction Cost

L

C$/Net kW1 $

455

4 ’

4-5

(37)

i

si

. .

1 4

-TABLE 4-1 [Cont'd)

55

MW (GROSS) GEOTHERMAL POWER PLANT

COST ESTIMATE

JUNE 1977

L

Account

Number D e s c r i p t i o n Man- hou r s

IJ

310 LAND AND LAND RIGHTS

-

! 310.1

31 0.2 Land and Easements

Wa t e r R i g h t s

I;

I

SUB TOTAL DIRECT

w

31 1 STRUCTURES AND IMPROVEMENTS

I 311.1 Improvements t o S i t e

-

hl 311.12 Plant Si%e

5 ,

799

31 1

.

14 Sewage Treatment Faci 1 i t i e s 438

311.15 Domestic Water System 266

31 1.3 Power B u i l d i n g

-

31 1.31 Substructure 8,092

311.32 Superstructures 12,190

311.33 B u i l d i n g Services 2,700

311.51 Fuel O i l Tanks (Including

Foundat ions) 250

311.52 Fuel O i l P i p i n g (Yard Only

-

B u i l d i n g 312.191) , 61 311.7 Administration B u i l d i n g and Lr, i

d

311.5 Fuel O i l System

-

i I n s u l a t i o n Here) 1,008 53

,

060 46

,

624

(Material Only) 646 28,530 '9,552

I 92,400

312.57

312.59 P i p i n g & Valve Suspense

(38)

. .

..

e c

Account Material & Labor

Man-hours Equipment Dollars Number Descri pt ion

31

4 TURBO-GENERATOR

UI4

IT

314.1

Turbine

-

Generator

314.11

Turbine Pedestal 314.12 Turbine

314.13

Generator 314.14 Turnincr Gear

8,671

125,145

91,457

17,000

4 ,

479,000 290,792

1

Included in Account 314.12

1

314. IS

Governing Control Sys-em)

314.16

Control and Stop Valve )

314.17

Gland Seal and Piping

1

314.18

Supervisory Instrumenta-)

tlon (Local Front

1

Standard)

1

314.19

(Lump All Process Instru-

314.2 Mlscel laneous Turbine- Included in Account 314.12

mentat ion Here) 4,800 154,500 82,106 Generator Equipment

{Supplied by Turbine- Genera tor Package)

314.3

Condenser and Auxll i-

aries

314.31

Main Condenser CSur-

face Type Including

1 n tercondensers) 11,000 gO0,OOO 162,686

314.-33

Ejectors Included in Acct.

314.31

314.34

Condensate Pumps

CSurface Type Cond) 2,300 500,000

34,016

314.36

Circulating Water Pipe

(Within Bui lding) 4,706

146,811

69,600

314.4

Coot ing Tower and

Equ I pmen t

314.41

Cooling Tower Basin and

Foundations 2,355 32,434 38,425

314.42 Cooling Tower 7,000

1

,000,000 98,222

314.43

Circulating Water Pump .

St ruct ure NONE

314.45

Circulating Water Piping

(!Outside Building)

7,384

261,114 109,555

3i4.46

Water Treating System

(For Circulating Water) NONE

314.47

Cathodic Protection Included in Acct. No.

314.45

{C. W. Piping)

314.6

Lube Oil System

{Including a1 1 equipment which is not furnished as

an integral part

of other equipment

314.35

Circulating Water Pumps

185

30,215 2,737

4-7

*

(39)

t

- c . .

i

%'

Account Material E Labor

Number Description Man- hours Equipment Dollars

Equ i pmen t

61

4

. 56,790 9,048

5,841

63,321 86,079

H2 and C02 System

(On

1 y equ i pmen t

which i s not fur- nished as an integ- ral part of other

equ i pmen t) 730 81,200 10,758

314.9

Auxlliary Generator

314.91

Diesel Engine Driven

Genera tor

346

20,630

5,463

314.61

Tanks, Pumps and

314.62 Lube Oil Piping

.

L

c

L

. 314.7

/ I - -f l

u

Sub Total 73,190 7,851,160 1,091,000 Use

As

73,200 7,850,000 1,091,000 r '

315

. ACCESSORY ELECTRICAL EQUIPMENT

b

315.1

Main Power Control

Equipment

(13.8

kV)

' I

i

.

315.11

Cubicles 240 .127,397

3 ,

790

u

315.14

Load Frequency Control Included in Account

315.41

315.15

315.16

Cooling Tower Control

315.2 Start-up Power

13,800 Volt Bus Duct and

u

Termi na

1

s 180 58,812 2,842

1 Equ i pmen t

315.22 Start-up Swi tchgear 30

3,576

.

474 li

- 1 r

315.3

Other Station Service

Control Equipment

-

d

4160 Volt

d

and Receptacles

315.31

Cubicles 250 40,808 4,158

315.32 Local Control Stations Included in Account 315.42

315.35

4160 Volt Bus Duct

315.4

Other Station Service

315.41

Electrical Control Board

315.42 Local Control Stations

1

315.34

4160 Vo1 t Transformers

160

35 ,

878

2,526

' (1200

A)

80

6,969

1,263

J,

1 Control

J & Supervisory Control 1,200

67,417

18,063

and Receptacles 470 10,000 7,075

d

315.43

Motor Control Centers 200 68,000 3,011

I