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AiResearch Energy Systems Applications of the 831Series Gas TurbinesRUSSELL V. HOFFMANChief Engineer,

El Segundo Facility,

AiResearch Manufacturing Company,A Division of The GarrettCorporation, El Segundo, Calif.

This paper discusses the commercial and industrial applications of the AiResearchModel 831 Turbopower Module. The 500-hp turbine is described with particularemphasis upon the functional and control characteristics that have gained for it anenviable place in the energy-conversion field. Accessory equipment such as exhaustheat exchangers, absorption chillers, and turbopowered compressors are describedin sufficient detail to enable the reader to understand their operation. Three typicalcommercial and industrial applications are described with particular emphasis onillustrating the economic feasibility of these on-site turbopowered energy systems.The results of the successful application of turbo-powered energy systems are tabulated.

Contributed by the Gas Turbine Division for presentation at the Gas Turbine Conferenceand Products Show, Houston, Tex., March 5-9, 1967, of The American Society of MechanicalEngineers. Manuscript received at ASME Headquarters, December 30, 1966.

Copies will be available until January 1, 1968.

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS, UNITED ENGINEERING CENTER, 345 EAST 47th STREET, NEW YORK, N.Y. 10017

Copyright © 1967 by ASME

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THREE STAGE TURBINE

Fig. 1 Model 831 industrial engine

AiResearch Energy Systems Applications of the 831Series Gas TurbinesRUSSELL V. HOFFMAN

Garrett Energy Systems convert fuel energyto shaft power and usable high-level thermal ener-gy. The shaft power may be used to drive elec-trical generators, fans, pumps, compressors, andso on. The turbine exhaust heat may be used di-rectly for air drying, large boiler preheat, pro-cess heating, or with heat-recovery units to gen-erate hot water or steam for air-conditioning,process steam, additional power source, and so on.

AIRESEARCH MODEL 831 TURBINE

The foundation of Garrett Energy Systems isthe 831 Turbopower Module. The power section ofthe module incorporates a Model 831 industrial gasturbine engine, controls, and primary gear reduc-tion. Cutaway views of the gas-fueled and liquid-fueled turbine engines are illustrated in Figs.land 2. Both engines are similar except for thecombustion configuration.

Figs.) and 4 depict the engine performanceas a function of ambient and inlet air temperature.

Fig. 2 Cutaway of typical Model 831 power section

1


0 20 40 60 80 1 00 120

AMBIENT AND INLET AIR TEMPERATURE, °F

Fig. 3 Maximum continuous performance Model 831-13industrial gas turbine generator set

5000

4800-20 1 00 1 0804020 600

a

82

500

480

0

400

380

360

340

6000

5800

5600

54 00

N (BTU/HR)

NOTE:

FUEL CONSUMPTIORASED ON LOWER HEATINGVALUE OF NATURAL-GAS FUEL

5200

GENENATOR7

SEC. GEARBOXTURBINE AIR INLET

URSINE EXHAUST

MODEL 831 GAS TURBINE ENGINE

Immo.MUM SEA

6000LEVEL

FTTO

1111111.11117

LIMMt ow11%

ME

ILMEM=

MUM

■11111.11111MINIM

RIM

III■

NOOUTPUT

NLET ORSHAFT

V.: 1000EFF:

KW GENERATOR

DISCHARGE LOSSE SPEED 8,495 RPM0 95, GENERATOR EFF. 0.90BTU/CU FT

AT 0.80 POWER FACTOR

GEARBOXL.H325 1

Fig. 5 Turbogenerator

Model 831 Specification (NACA std. day)

Type ................... simple cycle, single

shaft

Shaft power, hp ........ 500Fuels, Model 831-13 ..... natural gas or propane

Model 831-53 ..... diesels or distillates

Model 831-100 .... dual fuel applications

Nominal rotor shaft

speed, rpm ...... 39,000Compressor ............. twe-stage radial

Compressor ratio 7 1.1Airflow, lb/sec 5 56Turbine ................ 3-stage axial flow

Exhaust gas flow ....... 4370 scfm, 980 F

Exhaust heat, Btu/hr 3 325 x 10 6 Btu/hr

Primary gearbox ........ planetary type

Output speed, rpm ...... 8500

Reduction ratio 4 56:1

Secondary gearbox ...... double helical gear type

Output speed shaft,rpm...(a) 3600Output speed shaft,rpm...(b) 1800

Output speed shaft,rpm...(c) 1500

Output speed shaft,rpm...(d) other speeds avail-able for special

applications

PRINCIPLES OF TURBINE ENGINE OPERATION

Air enters the engine inlet plenum as shown

in Fig.1 and is drawn into the first-stage com-

pressor wheel for compression. An interstage

crossover duct assembly conveys the air from the

discharge of the first-stage compressor into the

inlet of the second-stage compressor for secondary

320

310

300

290

280

270

C 260

250

3 240

230

E-]220

210

200

1 90

1 80

1 70

flow

AMBIENT AND INLET AIR TEMPERATURE, °F compression. A diffuser and preswirl section actsFig. 4 Performance Model 831-13 industrial gas turbine engine to diffuse the second-stage compressor discharge

air to a low velocity and guides it to the turbineplenum assembly. From the plenum assembly, the

compressed air is directed through the single,

can-type, combustion-tube assembly.

2


12080 00 60 80 1 00

AMBIENT AND INLET AIR TEMPERATURE, °

F

Fig. 7 Performance Model 831-13 industrialgas turbine engine

1 030

3400

3500 k!,§

3000 11

am iE

2600

318,8

"4,

111'4°

CNT

300 K

250 KWGs.. 60

1116.

200 Kw

50 K

1 p0 KW

50

0 KW

OUTPUTNATURALGEARBOXL.H.V.:

SEA LEVEL, NO INLETSHAFT SPEEDGAS FUELEFF: 0.95,

1 000 BTU/CU

OR DISCHARGE8,495 RPM

GENERATORFT

--..

LOSSES

EFF: 0.90

20 40 60, 80 1 00 120


Fig. 6 Estimated nominal performance Model 831-13industrial gas turbine generator set

6000

5500

4200

4000

3200

3000

2500

Fuel is injected into the combustor through

a dual-orifice, pressure-swirl atomizing nozzle.

Combustion is initiated by a high-energy ignition

system and a single igniter plug. Combustion

raises the temperature of the compressed air inthe combustor.

After initiation of combustion, the ignition

system is automatically de-energized, and combus-tion is self-sustained during engine operation.The hot combustion gases pass through the first-

stage turbine stator vanes. The gases then are

expanded through the three axial-flow turbine

stages. The kinetic energy imparted to the tur-

bine wheels causes them to rotate, which provides

primary shaft power for operation of the compres-

sor, the gearbox, and the driven equipment. Dur-

ing normal operation, the speed of the rotating

assembly is maintained at a nominal value of ap-

proximately 39,000 rpm by means of the fuel gov-

ernor system. From the turbine, the combustion

gases are discharged through a short exhaust dif-

fuser incorporating provisions for attachment ofthe exhaust duct.

As the hot combustion gases expand acrossthe turbine, the energy imparted to the wheels re-

sults in a temperature drop, so that the tempera-

ture of the discharge (exhaust) air is a relative-

ly fixed value below the temperature of the air

entering the wheels, termed the turbine inlet tem-

perature. The power available from the turbine

wheels is a function of the turbine inlet tempera-

ture, which is limited to a maximum value consist-

ent with the intended usage or application. This

results in a fixed maximum turbine discharge tem-

perature that the engine will sustain. For long-

life applications this value is about 1000 to 1200

F under normal conditions, and generally is termed

turbine discharge temperature (TDT). The previ-

ously mentioned exhaust-gas overtemperature systemshuts down the engine if exhaust-gas temperature

becomes excessive.

TURBINE POWER SECTION DESCRIPTION

The rotating group of the turbine power sec-

tion consists of two centrifugal compressor wheels

and three axial-flow turbine wheels, all mounted

on a single shaft. The compressor wheels are ma-

chined titanium forgings. The turbine wheels are

machined from Inconel 713C investment castings.

The first-stage turbine wheel and first-stage

stator nozzle are aluminum-diffusion-coated to

prevent sulfidation-oxidation of these parts.

3


SEA LEVEL, NO INLET OR DISCHARGE LOSSESOUTPUT SHAFT SPEED 8,495 RPMHEAT CONTENT REFERENCED TO A BASE (STACK)TEMPERATURE OF 325

°F

GEARBOX EFF: 0.95, GENERATOR EFF: 0.90L.H.V.: 1000 BTU/CU FT

tratellpalitalliffirUM

I i iti.11111

1 200 KW INIII50 KWoil PIEZERO K4

20 40 60 80 100 120


Fig. 8 Estimated nominal performance Model 831-13industrial gas turbine generator set

This is a constant-speed machine, with the nominal

speed being approximately 39,000 rpm.

The rotating group is supported in the en-

gine housing by means of bearing and seal assem-

blies located outboard of the first-stage compres-

sor wheel and the third-stage turbine wheel. The

bearing and seal assemblies are encapsulated to

permit field removal and replacement without dis-

turbing the rotating-group.

The turbine-end bearing is a floating sleeve

journal type. This bearing has much longer life

than a ball bearing, especially at elevated tem-

peratures. The bearing has been designed to oper-

ate in excess of 10,000 hr.

For easy access, inspection, and maintenance,

the liquid fuel combustor component, Fig.2, of the

power section consists of a single-can combustion

flame tube and scroll section, mounted within aplenum assembly circumventing the turbine end ofthe engine housing, and a dual-orifice pressure-

swirl fuel atomizer. The gaseous fuel combustor

is of annular design with integral fuel nozzles.

A single igniter plug is mounted on the combustor

for initial spark-ignition of the fuel. Electric-

al power is supplied to the igniter plug through

a high-energy ignition unit and a high-tension

lead assembly. Pressure distribution by design of

louvers and holes in the combustor can are such

that proper gas flow eliminates peak-temperature

spots and poor combustion areas.

i1

I\ \\ \

\\

\ --,■

----...........--- --____

500 1 500 2000 2500 5000 3500

SHAFT HORSEPOWER

Fig. 9 Gas turbine specific fuel consumption comparisonat NACA standard day conditions

A torsion quill shaft connects the compres-

sor end of the rotating group with the input side

of the gearbox and accessory drive section.

An exhaust tailpipe is attached to the tur-

bine housing to diffuse the exhaust gases to re-

duce pressure losses. The tailpipe also provides

mounting bosses for an exhaust-gas thermocoupleand overtemperature protection system. It termin-

ates in a flange for connection to a customer-

furnished exhaust duct.

Primary Gearbox DescriptionThe primary gearbox consists of a planetary

reduction to 8500 rpm. The accessory-drive spur-gear train is driven by the first planetary reduc-

tion section, which permits independent single-

power-section operation. The gearbox is a rugged

industrial unit designed for a minimum of 20,000hr of service. A cast-iron gear case and heavy-

duty spur gears assure long life and reliability.

The gearbox is gravity-drained but can be modified

for scavenging.The main output consists of a stub shaft,

25/8 in, dia and 5 in. in length. Rotation is in

the clockwise direction, seen facing the drive pad.

ENERGY UTILIZATION

Turbogenerator

The turbogenerator shown in Fig.5 utilizes

the Model 831 Turbopower unit connected to a gen-

erator to produce 320 kw at NACA std, day condi-

tions with no inlet or exhaust losses. The gener-

ator is a 120/208-volt or 227/480-volt, 3-phase,

60 cps, 4-wire, 0.8 pf Wye connected air-cooled

unit. The unit is designed to meet ASA Standard

CS0.1-1955, NEMA M6-1, and latest 1 EEE standards

for heating, wave shape, overspeed, balance, short

3600

3200

R 2800

E 2400

2000

1 600

1200

800

30

c/ 25

20

LL

IS

g 0

4


RECIR CULA-FINGPUMP

MEAT EXCMANL ER FUEL •UNDER GASINWSW. FOR STARTER

Fig. 10 Schematic diagram

circuit, telephone interference, interferencefactor, and so on. The voltage regulator is a

Fig. 11 Typical water-tube heat-recovery boiler

The system is visualized as a gas turbine

driving a centrifugal compressor for the cooling

system and an alternator. When electrical power

is required owing to an emergency demand, the in-

let guide vanes of the compressor close, reducingthe power demand of the chiller circuit. The gen-

erator is loaded by closing relays. In this way,transistorized static type utilizing 28-vdc bat- uninterrupted electrical service can be maintainedtery power from the turbine start battery, thus at the expense of reducing the capacity of aireliminating the need for short-circuit boost cir- conditioning of a building, but without the ex-cuits. The output voltage regulation is within pense of an unused standby generator set.± 0.5 percent under steady-state conditions of no- The refrigeration system shown in Fig.lOload to full load. With rapid applications of consists of the following: The single-stage com-load from no-load to rated load, the output voltage pressor has been specifically designed for use onrecovery is within ± 1.0 percent of the preset the AiResearch Model 831 gas turbine engine. Itvoltage within one second. The turbogenerator operates at 39,000 rpm and features pressure-lub-module is designed for a high degree of design ricated journal bearings, labyrinth seals duringflexibility for modular installation. Any number operation, and a static seal for nonoperatingof sets can be operated in parallel and are ideal- periods. Capacity is controlled by variable inletly suited to provide varying electrical load de- guide vanes operating in response to chilled watermands by operating the minimum number of sets at temperature.maximum fuel economy. The evaporator and condenser are standard

The turbogenerator performance is depicted horizontal shell and tube design. The tubes areby Figs.6 - 9. Fig.9 shows a comparison of spe- of the extended-surface type for improved heatcific fuel consumptions of various U.S. manufac- transfer. Tube ends are belled to improve flowtured gas turbine engines. The values were taken characteristics and permit normal maintenance pro-from manufacturers' published data and represent cedures. They conform to ASME code and are con-the "best case" for each. The curve illustrates structed and tested in accordance with ASA B9.1how the small gas turbine is best suited to appli- safety code for mechanical refrigeration.cations having load profiles closely approximating This system can be designed to providethe design point of the engine. Typical load pro- either 150 kw of electrical power or 400 tons offiles shown later in this report illustrate how refrigeration.the modular approach of matching multiple turbine

sets to the profile results in maximum fuel HEAT-RECOVERY SYSTEMeconomy.

TURBOCHILLER SYSTEM

Most of the major applications of the 831-series gas turbine have been for production of

electrical power, although a natural application

for future development is to utilize the gas tur-

bine to drive a centrifugal chiller for air condi-

tioning as a primary mission, and also provide a

method of converting the unit to electrical outputfor a standby generator set.

The turbine exhaust temperature is approxi-mately 1000 F, is extremely clean, contains no

measurable quantity of carbon monoxide, oil or

other contaminants, contains upwards of 15 percent

oxygen, and is available at reasonable static

pressure from the exhaust breeching of the turbine.

This hot "air" can be used in many drying opera-tions directly, or as preheated combustion air for

kilns, boilers, and so on.

The hot turbine exhaust can be used to pro-

duce steam at up to several hundred pounds pres-

5


STACK Al250 PSI

STACK -50 'SIC 2.05 •

7111.111E EXMA11,

PRE.. LI.T

M 5102. W5

so rsto see*

5 PSIC 520. G

AVAILABLE HEAT 250 PS/

AVAILABLE HEAT A7 150 PSI

3 0

MILL ION AM1LAM

Fig. 12 Heat recovery per turbine

sure. If high-pressure steam, for steam turbines

for example, is not needed, low-pressure steam at

15 psig can be generated and used for space heat-

ing, water heating, process heating, and absorp-

tion water chilling for air conditioning. Fig.l1depicts schematically a typical water-tube type

heat-recovery steam boiler.

High temperature water is also used as a

heat-recovery medium. This water will be at a

temperature of 160 to 200 F if used for domestic

hot water service, 170 to 250 F for space heating,

220 to 250 F for absorption-type air conditioning,

and even higher for certain special conditions

such as feed-water heating. Where high-temperature

water can be used in place of steam, it has sever-

al advantages. These advantages are: smaller

boiler size because of higher thermal capacity per

cubic foot of water versus steam; less water make-

up treatment; and use of smaller line sizes.

Heat-recovery boilers are economically at-

tractive in recovering heat from gas turbine ex-haust. The equipment is reliable and inexpensive

because it is basically a heat exchanger and does

not require the radiant surfaces and high-tempera-

ture refractory of a conventionally fired boiler.

When supplementary firing is used to produce addi-

tional steam, with the increased steam flow the

temperature of the exhaust gas from the boilerwill be nearly the same as it would be without ad-

ditional firing; thus the efficiency will remain

high.

Heat-recovery boilers are either firetube or

watertube. In most applications the heat demandvaries over a wide range, with a resulting need of

automatic control. The exhaust heat system con-

sists of the exhaust heat boiler, the condensate

return system, the exhaust duct system, and the

boiler stack, with fully automatic controls and

protective devices that eliminate the need of an

operator in attendance. The ducting can be de-signed so that either all or part of the exhaust

(EVAPORATION - TURBINE ONLY

1 1FIRING -.....

/A/----

MAXIMUM BOOST

A/RESEARCH

STEAM AVAILABLE

15 PUG FEEDWATERBOILER EXHAUST

GT 831-13

AT.

GAS TEMP.

TURBINE

- 200°P320

°E

c',1,%

C"'../

e/

'3..' ,

0';>

....... 0

,..0

....,

II pm-

00 TOO 700 800 900 1 000 11 00 200

TURBINE EXHAUST GAS TEMPERATURE, 7 E

Fig. 13 AiResearch GT 831-13 turbine

gas can be bypassed. One or more gas turbines can

be manifolded into the same exhaust heat boiler.

The steam available from a gas turbine boiler is

from 8 to 10 lb/hr per turbine hp of 15 to 150-

psig steam. Saturated steam at 10 to 15 psig can

be used for water heating, space heating, and ab-

sorption air conditioning, and at 150 or 250 psig

in a steam turbine to drive pumps, compressors of

various types, or generators.Higher steam pressures and temperatures are

available. For example, steam at 600 psig and

750 F is being produced from the exhaust alone of

a gas turbine installed at a natural gas pipeline

compressor station. This boiler has a superheater

section arranged similar to that of a conventional

type of fired boiler.With supplementary firing the turbine exhaust

is treated as a high-temperature air supply. Fuel

combustion raises the temperature of the hot gases

to the desired level, and the installation willthen be a fired boiler with a range of pressures

and temperatures available to satisfy almost any

purpose. A final stack exhaust temperature of 325

F is usually desired to avoid the formation of

condensates. The condensates formed at a lower

exhaust temperature may be highly acid forming

(such as carbonic acid), which can cause severe

corrosion.

Exhaust heat from the turbine can also be

partially used back in the turbine cycle in a re-

generative or recuperative arrangement. The use

16

16

12

1 0

8

S

2

6


AI I II

itGENERATOR o.

Fig. 14 Absorption chiller

of this heat to do some of the heating of the com-pressed air reduces the fuel required for burning

in the combustion chamber of the turbine. The

compressed air may be at a temperature of several

hundred deg, so there is a limit as to how much

the exhaust can be cooled in a heat interchange.

Therefore, considerable heat remains in the ex-

haust after being used in the recuperator. This

remaining heat is then passed through an exhaust

heat-recovery steam boiler or water heater.

Fig.12 shows the performance of one heat-

recovery unit manifolded to one 831 turbine. Fig.

13 shows performance with multiple turbines mani-

folded to a single heat-recovery unit. Additional

heat can be added by use of integral firing units

to meet requirements in excess of turbine output,

or installation of immersion heaters.

ABSORPTION CHILLER COOLING SYSTEM

Fig. 15 Absorption cycle schematic

A water coil is placed inside the evapora-

tor; thus, water circulated through the coil is

chilled by the cold water. The coil is wetted by

a spray header and pump to increase the heat-

The absorption cooling cycle is one of the transfer efficiency. Because the evaporation

oldest methods of cooling. It has been perfected takes place at high vacuum, chilled water tempera-

in the last decade to give operating economy plus tures as low as 38 F may be obtained.

automatic control and economical installation to The water absorbed by the concentrated solu-

building owners. Fig.14 shows a typical absorption tion weakens the concentration. If the cycle is

machine and Fig. 15 depicts the cycle schematically, allowed to continue, the solution would eventually

The refrigeration cycle operation requires reach a point where it would no longer absorb

two vessels, one containing concentrated salt or water. To continue the cycle, the solution is

ammonia solution, and the other vessel plain water, transferred to another compartment where heat

The two vessels are connected with piping, and, boils off the water collected.

just as common salt absorbs water from the air on After the solution has the water removed, it

a damp day, the concentrated solution starts to is once again transferred to the absorber to con-

evaporate some of the plain water. This evapora- tinue the cycle. The water removed by the boiling

tion causes the remaining water to be chilled, and action is condensed and returned to the evaporator.

thus a refrigeration process is effected. Condenser water is circulated through the machine

7


to condense the water vapor and cool the reconcen-trated solution.

Steam or hot-water-driven absorption units

are available in sizes from 50 to 1000 tons.

These units require larger space and are heavierper refrigeration ton than reciprocating or cen-

trifugal chillers of corresponding tonnage. How-

ever, the absorption machines provide quieter

operation, no vibration, high dependability, and

minimal maintenance. The quiet, vibration-free

operation is possible since the machines requireonly three small feed pumps. The absorption

chiller also has efficiency capacity control; ab-

sorbent is reconcentrated and circulated at a rateto produce the desired chilled water temperature.

Through the use of this method of capacity control,

the absorption chiller can operate at 10 percent

of full load and maintain high efficiencies. Steam

rates for absorption chillers are 17 to 20 lb/ton.

Operational steam pressures are 8, 10, and 12 psi.

Hot water under pressure can be used in absorption

chillers at temperatures ranging from 255 to 400 F.

The absorption chiller requires a large

cooling tower and condenser water pump. The high-

er temperature water over the cooling tower re-

sults in increased evaporation along with the aux-

iliary pump horsepower. This operating cost in-

crease, however, is more than offset by the over-

all economy of the energy source gas. The boiler

used to produce heat in the winter also provides

cooling in the summer. The steam that is a by-

product of turbine-driven electrical power genera-

tion drives the absorption chiller and increases

the overall coefficient of performance.

ON-SITE GENERATING SYSTEM CONTROLS

The turbine generator set controls used inon-site generating systems can be separated into

two basic categories, single-unit controls and

system controls. Similarly, single-unit controls

can be divided into two groups; those integral to

the turbine generator and those that are remotely

located.

Fig. 16 Fuel and airflow schematic

The single-unit controls that are integralto the turbine generator set include the mechani-

cal governor control, start cycle controls andturbine safety devices. The mechanical governor

automatically controls engine speed (and, indi-

rectly, exhaust temperature) within predetermined

limits by metering fuel flow to the combustionchamber through the Fuel Control Valve.

This pneumatically operated, spring-loaded,

spool-type modulating valve regulates fuel flow

to the combustor in response to engine load re-

quirements, utilizing compressor discharge pres-

sure and engine speed as primary control signals

During acceleration to governed operating

speed, the rate of change of fuel flow to the com-

bustor is controlled by the acceleration limiting

solenoid valve. When 95 percent of governed oper-

ating speed is reached, the acceleration solenoid

closes. A second solenoid valve opens to admit

filtered control air to the speed trim metering

section of the fuel control assembly, and the fuel

flow rate is controlled by the mechanically driven

speed sensor to maintain a preset engine rotor

speed (3 percent droop, no-load to full load).

The speed trim metering section incorporates

a torque motor override control. For electrical

power generation systems, electrical signals maybe applied to the torque motor from a speed error

detection system to maintain isochronous speed

control (± 1/4 percent is possible). Signals also

may be applied to the torque motor from a load-

sharing system to control engine speed for load

division and electrical paralleling of two or more

engine generators. Speed error detection and load-

sharing systems are available as optional equip-

ment and are discussed as remote located turbine

generator set controls.The fuel and airflow schematic of the tur-

bine and fuel control valve is shown in Fig.16.

The start cycle controls provide for a 30-

sec purge cycle during which the unit is motored

on the starter motor. This insures that prior to

ignition the turbine exhaust system and the tur-

bine generator enclosure are purged of any possi-

ble gaseous fuel vapors that might be present in

the event of a fuel system leak. At the comple-

tion of the purge cycle, cranking speed and oil

pressure are monitored and, if these are above

preset limits, ignition is permitted. The enginemust then achieve rated speed within a period of

60 sec or the overcranking device will automatic-

ally shut down the unit. Turbine safety shutdown

devices, other than overcrank, include high-

exhaust-temperature, high-oil-temperature, low-oil-

pressure, low-fuel-pressure, underspeed and over-speed. High vibration safety shutdown is also

available as optional equipment.

8


The majority of the control components es-sential to the turbine operation are integrated

into the turbine control printed-circuit boardlocated near the turbine. The turbine control

circuit provides for safe turbine start-up, tur-

bine fault annunciation and shutdown control, as

well as normal turbine stop controls. All of the

solid-state circuits have been desensitized to

voltage fluctuations.

The components consisting of 55 percentsolid-state devices and 45 percent relays aremounted on the more reliable printed-circuit board.

All-solid-state timing networks are used to givegreater reliability and instant resetability. The

turbine control circuit can be operated from 18 to

32 volts. The timing circuits are not affected by

voltage variation from 16 to 32 volts since they

contain their own voltage regulators.

Fault annunciation is of the first fault in-

dication type and is accomplished through the use

of silicon controlled rectifiers. Fault indica-

tion remains, after the turbine is stopped, until

reset.

A block diagram of the controls integral to

the turbine is shown in Fig.17.

GENERATOR CONTROL CUBICLE

The single-unit remotely located turbine

generator controls are housed in the Generator

Control Cubicle.

The cubicle design provides for easy indus-

trial maintenance of all components, with all com-

ponents furnished by major manufacturers and eas-

ily obtained throughout the world. Generator in-strumentation is of the switchboard class, which is

widely used throughout the electric utility indus-

try and powerhouse applications and is rated for

one percent accuracy. A draw-out type, electrical

ly operated, 600-amp, air-gap circuit breaker is

included as standard equipment. This provisionpermits complete circuit breaker removal for test-

ing or maintenance without necessitating a system

shutdown. It also permits testing complete break-

er operation without actually closing the circuit

between the generator and the bus.Complete annunciation, protection and con-

trol of the generator are performed in the control

cubicle. All necessary controls for manual and

automatic paralleling and load sharing with simi-

lar turbine generator sets are included as stand-

ard equipment. Also included are complete manual

turbine controls and a single-condition-readout

fault annunciator.

Major electrical components of the system

include the circuit breaker; three overcurrent-

relays, one per phase; reverse-power-relay, auto-

Fig. 17 Turbine generator set block diagram

matic synchronizing relay; electronic turbine

governor control; generator control printed cir-

cuit, including overvoltage and undervoltage pro-

tective circuit; voltage regulator; ammeter with

switch; voltmeter with switch; kilowatt-kilovar

meter with switch; frequency meter; synchronizing

switch; and turbine speed and exhaust temperature

indicators. All components are housed in a 36 x

90 x 54 in. free-standing cabinet.The majority of controls necessary for pro-

tection of the generator and proper operation ofthe circuit breaker are located in the generator

control printed-circuit board. This printed-cir-

cuit board monitors the generator voltage output

with integral, transistorized undervoltage and

overvoltage fault circuits. It also prOvides

fault circuitry for overcurrent and reverse power

conditions. The printed circuit controls all

circuit-breaker trips and prevents breaker closure

before generator voltage build-up.

The fault annunciation circuit is designed

to indicate first fault only and utilizes the

latch-on characteristics of silicon controlled

rectifiers. All timing circuits are solid state

and operate from their own voltage regulator. The

solid state circuits have been desensitized to dc

voltage transients.A time delay is provided in the undervoltage

trip circuit in order to prevent nuisance trips

owing to momentary voltage dips.

The overvoltage circuit operates on an in-

verse time function such that the magnitude of thevoltage determines the time in which the unit will

be de-energized and removed from the system.

There are two basic modes of operation of

the turbine generator set, Manual and Automatic.

The mode of operation is chosen by means of the

Mode Selector Switch on the door of the Generator

Control Cubicle.

In the Manual Mode, turbine start up is ac-

complished by the "Start" pushbutton on the door

of the cubicle. After completion of the turbine

9


WinCIATORSANDCONTROLS NRBIN,

PROGRAMMER I. O.SENSOR

Fig. 18 Control switchgear block diagram

purge cycle, ignition occurs and acceleration be-gins. After the turbine reaches governed speed,

all turbine fault circuits are armed and turoine

running condition metering is actuated. The gen-

erator is energized by the "Manual Generator Arm"

pushbutton on the cubicle door. At this time all'

generator metering and generator protective cir-

cuits are activated. In order to close the cir-

cuit breaker and load the unit, it is first neces-

sary to place the "Synchronizing Switch" in the

"On" position. If the system bus is de-energized,

the circuit breaker "Close" pushbutton may be im-

mediately depressed to close the circuit breaker.

If the bus is energized, the operator must wait

until the generator and the bus are electrically

synchronized, as indicated on the System Synchro-

nizing Panel, and then press the "Close" push-button. The unit is then in its normal operating

condition.

If the unit is placed in the Automatic Mode,

the turbine start signal must be supplied from an

external source. Upon receipt of this signal, the

unit will automatically sequence through turbine

acceleration, generator arming, and circuit-break-

er closure, including bus synchronizing if neces-

sary.Single-fault-annunciation of any turbine

generator fault condition is provided on the cubi-

cle panel. These fault conditions include

1 overcurrent

2 overvoltage3 undervoltage

4 reverse power

5 underspeed6 overspeed

7 high exhaust temperature8 high oil temperature9 low oil pressure

10 low fuel pressure

11 overcrank

12 high turbine vibration (optional)

A block diagram of the control cubicle is

shown in Fig.18,

Standard system performance includes steady-

state voltage regulation of 0.5 percent from no-

load to full load. Steady state frequency, or

speed, regulations of 0.25 percent from no-load

to full load are included as standard capability.More precise frequency control can be obtained by

inclusion of the frequency standard kit as option-

al equipment.

MASTER CONTROL CUBICLE

Automatic system operation in multi-unit in-

stallations requires the addition of a Master

Control Cubicle and Synchronizing Panel. The

Master Control Cubicle contains the system annun-

ciation and manual system controls, as well as

mounting provisions for the auxiliary system sens-

ing equipment. When installed with appropriate

optional equipment, the Master Control Cubicle

provides safe, dependable, fully automatic system

operation, completely unattended for extended pe-

riods of time.

System annunciators are cumulative-units-

running, units-locked-out, units-faulted, and load

shed. Manual system controls include a Lead Unit

Selector Switch, a Unit Control Selector Switch,

a Unit-Lockout, a Fault Reset and a Load-Shed Re-

set pushbutton. Auxiliary system sensing equip-

ment consists of totalizing current and potential

transformers. Optional components include a Bus

Load Sensor, a Turbine Programmer, a Load-Shed

Programmer, and a Frequency Standard Kit. Incor-

poration of the Master Control Cubicle into a sys-tem also provides for the installation of bus bars

and termination points for power connections.

A block diagram of the Master Control Cubi-

cle is shown in Fig.19.

STANDARDCLOCK

0 TURBINCENERATORS

TC .,,MERLG,SHEDCI , CAT,REAKE , S

Fig. 19 Master control cubicle block diagram

10


BUS LOAD SENSOR

The Bus Load Sensor is designed to operate

in conjunction with the Turbine Programmer and is

offered as option equipment when the programmer is

included in the system. The combination of the

Bus Load Sensor and the Turbine Programmer is

recommended for multi-unit energy system applica-

tions where automatic unattended operation is de-sired.

The Bus Load Sensor contains the necessarycircuitry to monitor system output, and produces

an analog dc signal proportional to the kilowatt,

real load, output of the system. This sensor dif-

fers from current sensing systems in that it is

not unduly biased by highly inductive loads such

as motor startings -- sensing kilowatts rather than

current avoids nuisance turbine starts and stops.The sensor is designed to be located in the

system Master Control Cubicle front compartment

and consists of nine control transformers, seven-

teen control diodes, biasing resistors, filtering

capacitors, and an output control transistor. The

ac voltage level of the system is sensed by thefirst stage of transformation and compared with

the current level and phase angle in the second

stage of transformation. The resulting ac signals

are then put into diode rectifier bridge and the

dc output is used to bias the output control tran-

sistor. The transistor then controls a filtered

dc signal output which is directly proportional to

the kilowatt output of the system. This signal isthen monitored by the turbine programmer to start

and stop turbines as required by the electricalload of the system.

TURBINE PROGRAMMER

The Turbine Programmer incorporates two op-

tical-type meter relays with adjustable set points,

an add-subtract stepper relay, seven time-delay

relays for proper sequencing and interval timing,

and load level and start-stop logic relays. The

system load level is sensed by an external real

load sensing device which produces a dc analog

voltage proportional to load. This signal is fed

to the programmer to directly bias a precise refer-

ence voltage which is developed across any one of

five Zener reference diodes, the level being de-

pendent upon the number of units supporting the

load. The load level controls and the add-sub-

tract control circuits utilize seven transistors

to switch-in the appropriate adjustable control

potentiometers. This method permits the operator

the flexibility of setting the programmer to any

percentage of real load at any of five separate

load increments.

In addition to the load control functions,

the programmer recognizes when a unit has been made

unavailable for service due to normal maintenance,

and skips to the next available unit without at-

tempting to start the locked-out unit. The pro-

grammer also recognizes when a unit malfunctions

during service and, upon a fault, produces a faultsignal to the Load-Shed Programmer and a start

command to the next available unit.

LOAD SHED PROGRAMMER

The Load Shed Programmer is designed to be

used with the Turbine Programmer and the Bus LoadSensor and is offered as optional equipment when

the Turbine Programmer and the Bus Load Sensor are

included in the system. It is recommended for in-

stallation in all multi-unit, automatic energy

system applications to ensure continuous system

operation.

The Load Shed Programmer contains the relay

logic circuitry for the control of customer sup-

plied load-shedding circuit-breakers and provides

selective load shedding based on the post-fault

condition of the system. The programmer also pro-

vides for two stages of automatic load reset after

a standby turbine has been started and placed on

line. A third stage of load reset which is

manually controlled by a pushbutton on the door

of the Master Control Cubicle is also provided.

The Load Shed Programmer is de-signed to fit into

the front interior compartment of the Master Con-trol Oubicle.

The Load Shed Programmer continuously moni-

tors the number of units running, as signaled fromthe Turbine Programmer. When a unit fault occurs,

the number of units running immediately is lowered

by one. Then, upon receipt of the fault signal,

the Load Shed Programmer starts the appropriate

relay sequence to signal for load shed, depending

on whether one unit, two units, or three units or

more are running after fault. Completion of the

sequence provides a momentary, two-second, ten-

ampere, dry-contact closure across lighting shed

terminals. Also provided is a maintained ten-

ampere, dry-contact closure across motor shedterminals.

When the standby unit has been started and

is on the line, the number of units running re-

turns to its prefault level. At that time the

load reset sequence starts. In the completion of

this sequence a momentary, two-second contact clo-

sure occurs across the first lighting return

terminals. Five seconds later a momentary two-

second contact closure occurs across the second

lighting return terminals. Upon pressing the

Load-Shed Reset pushbutton on the Master Control

11


1COOL]COIL I

NATURAL GAS

AS 1.17ig

it I

TURBINEGEAL SET

TURBINE ■•••GEN.SET

TURBINEGEN.SET

...CHILLEDWATER

CHILLED WATERRETURN

^►BUILL'ING NEAT

SWIMMING rPOOL

NEAT EXCHANGER

COOLING TOWERS

,...-StMLOINO HEATRETURN

......ANTIFREE:ESOLUTION• ANTIFREEZE

SOLUTIONRETURN

■r•

ABSORSTIONCHILLER

BUILDING 14'HEAT EXCHANGER

4— BUILDINGHEAT EXCHANGER I ^

ANTIFREEZE CISOLUTION

HEAT EXCHANGER

GEN.VOLINGEXHAUST

,r PROPANECRITICAL--

VOYOLTS STAND-BYovcAsi,E NON-ccunt A‘l SYSTEM1,34,4,44 LOAD

OIL COOLING IEXHAUST TURBINE

CONTROLS

OMBUSTION AIR

to, COOLING AIR

romalcuwaR

DIVERTING• VALVE

1.• ILENCER:

44*

MIX NGCHAMBER

, 'Lr_4►EXHAOST

DOMESTICI HOT WATER

HEATER

Cubicle, the previously closed motor shed contactswill open.

PRECISE FREQUENCY STANDARD KIT

The Precise Frequency Standard Kit is avail-able for any system regardless of the number of

turbine generator modules. This option is design-

ed to restrict energy system frequency deviationto within 30 sec per month of standard time. For

large systems, the Frequency Standard Kit can bemounted in the Master Control Cubicle. In addi-

tion, a standard-time clock and a bus-time clock

are mounted on the Master Control Panel for time

comparison. To compensate for any malfunctions

or variations that might occur, "Add Bus Time" and

to barometric or altitude changes. The fork is

shock mounted so that the unit does not require

special mounting. The operating Q of the fork,

the measure of selectivity of the circuit, is in

excess of 5000.

The square wave, 60-cps output of the in-verter is fed into one end of a rotating synchron-

ous differential assembly. The other end of the

differential is fed by the system bus. Any fre-

quency deviation between the two inputs results in

a mechanical displacement of the rotating poten-tiometer which produces a positive or negative

signal simultaneously to all of the fuel controls

on the operating units to increase or decrease the

system frequency until it is in phase with thestandard.

"Subtract Bus Time" pushbuttons are mounted on the

Master Control Panel for rapid time corrections. SYNCHRONIZING PANELThe Frequency Standard Kit is a ten-watt

power inverter whose source of accuracy is a pre-

cision tuning fork of bimetallic construction to

virtually eliminate the effects of any temperature

changes. The drive and pickup system is electro-

magnetic. Driving force is applied to both tines

of the tuning fork and pickup voltage is generated

by the motion of both tines. The assembly is

housed in a hermetically sealed and partially

evacuated housing. The fork is thus also immune

The Synchronizing Swing Panel is recommendedfor incorporation of multi-unit energy systems

using a Master Control Cubicle. The panel pro-

vides for manual paralleling of generators and for

manual system operation in the event of a malfunc-

tion in the automatic synchronizing system.

The panel contains a pivot and jewel bearing

mechanism, self-contained synchroscope, two syn-

chronizing lamps, and two voltmeters. The lamps

Fig. 20 Typical apartment schematic

12


T TURBI NEGENERATORNODULE

TURBINEGENERATOR

TuRBNEGENERATOnODuLE

TURBINECONTROLS

fu,

DIRECT ExaAuST NEATER PROCESS WISTERCONTROL

DOMESTIC HOTWATER SYSTEM

SPACE HEATINGSYSTEM

LIGHTINGCIRCULATION FANSELEVATORSETC.

ELECTRICPOWER METER

ELECTRIC

NATURAL GAS H METER

AIR CONDITIONINGSYSTEM

'E'LECTRICAL

LOAM SCHEMATIC FOR EACH TENANT

Fig. 21 Typical process plant

are wired to indicate in-phase voltage when both

are dark and the voltmeters are wired so that one

monitors bus voltage and the other monitors incom-ing unit generator voltage. Instruments and lamps

are mounted on a 20 by 14 by 10-in, swinging cab-

inet which is mounted at eye level on one end ofthe control cubicle assembly. By proper position-

ing of the cabinet, it is possible to visually ob-

serve the instruments and lights from in front of

any control cubicle.

TYPICAL APPLICATIONS

Garrett Energy Systems employing the 831

series turbine engines are utilized in many indus-trial and commercial installations. Three typical

installations will be discussed in this section.

The first is an apartment house located in the

western part of the United States. In this system,

the exhaust heat is utilized for air conditioning,

swimming-pool heating, building space heating,walks heating, domestic hot-water and garage heat-

ing. A schematic of this system is shown in Fig,

20. Note the standby propane fuel system. This

qualifies the owner for a very inexpensive inter-

ruptible gas rate.The second application is a typical process

plant in which the exhaust heat is used directly,

eliminating the need for boilers or water heaters.

This system is shown schematically in Fig.21. In

this application, the customer can utilize all

available exhaust heat in a drying process for a

commercial product.The third application is a shopping center

located in the southern part of the United States.

This shopping center will be analyzed as an exam-

ple of the economic feasibility of a turbine-powered on-site energy system. The design parame-

ters for the shopping center are given in Table 1.If an on-site energy system is viewed as to

its economic worth, there are a few immediate ques-

tions which have to be answered. Assuming thatthe owner of the shopping center wishes to sell

Fig. 22 Individually metered purchased power system

the services of the on-site energy system, he

needs to know what the store owners (tenants)

would pay for their utilities and how much the

utilities would cost the owner to produce. Coupled

with this is the matter of the initial capital

cost for the various energy systems under consider-ation.

In order to determine the value of the util-

ities it is necessary to assume that the tenant

could purchase electric power and natural gas from

the appropriate utility companies delivered to hisown meters. With this type of conventional util-ity system the tenant would normally own and main-

tain his own heating and air-conditioning equip-

ment. This is the first system we will consider.

If the owner of the shopping center is to

sell the electric power, the steam or hot-water

service (for producing hot water and for spaceheating), and the chilled-water service (for air

conditioning), he must either purchase electric

power and natural gas from the utility companies

or use a readily available fuel and generate the

electrical power and thermal energy. It can be

seen that three utility systems must be analyzed

in order to provide a clear economic picture with

which to evaluate the shopping center. These sys-

tems are as follows:

1 Individually Metered (per tenant) Pur-

chased Electric Power and Natural Gas Systems --using electric power for air conditioning, light-

ing, utility outlets and air circulation equip-

ment; and using natural gas for hot water and

TABLE 1

2Peak Elec.Load 2Peak

Area(ft ) Density(Watts/ft ) Demand (KW)

26 Small Stores (0-2000 ft2each) 227,450 4.5

20 Medium Stores (2,001-10,000 ft each) 87,015 4.1

large Department Store 1 99,922 5.5

13,500 4.5

13,50o 4.5

102,764 4.5

1 2,000 4.5

12,000 4.5

48,780 2.5

Totals 516,931 ft

Description

Variety Store

Women's Clothes Shop

Department Store

Men's Clothes Shop

Cafeteria

Enclosed Mall

Parking lot and Signs

123.5

3571100

60.760.7

462

54

54

1 22

110

MT KW

13


0"PsI

BUILDINGHEATINGSYSTEM

TYPICAL( I I PLACE SI

AuXIJARY

FIRED

BOILER

41'_LL.

ABSORPT 0

CHILLER

0

DOMESTIC

HOT WATERSYSTEM

BUILDINGCOOLINGSYSTEM

5000DOMESTIC HOTwATER SYSTEM

NAT,OLGAS

DI,ECT FIRED B.,ILDENG 4000

BOILER HEATINGSYSTE,

3000

,ELELECT

SYSTEm

2000F--mFlt , I LOull,

_JTO EA, TENANT

Fig. 23 Central purchased power system 1000

SUMMER WEEKDAY

/-l4 INT ER WEEKDAYS_,. 1

1i

-- I

_ .

SUNG-

_ ...

_r.1

M 2 4 6 8 ■ 2 4 16∎ 18 20 22 M

TIME OF DAY, HR

Fig. 26 Electrical load profiles — central conventional systemBUILDINGELECTRIC NATURAL SAS

TURBINE CONTROL TYPICAL LOAD

CUBICLES (II PLACES' GAS

METER

TURBO-POWEREDGENERATOR MODULES

EXHAUST HEATEXCHANGERS

COOLINGTOWERS

Fig. 24 On-site turbopowered system

4000

3500

3000

2500

2000

■%

=.1

1500

1 000

500

0

space heating. The utility costs for the parking

lot, the mall, and the signs are prorated among

the tenants, Fig.22.

2 Central Purchased Power Utility Plant

System -- using electric power for a central

chilled-water air-conditioning system, selling

electric power to each tenant (only with permis-

sion from an electric utility) and using naturalgas for a steam or hot-water system to supply hot

water and space heating, Fig.23.

3 Central On-Site Turbopowered Utility Sys-

tem -- turbine-engine-driven generating system

utilizing exhaust heat recovery for air condition-

ing and space heating, Fig.24.The next step of the feasibility analysis is

to estimate electric load profiles for typical

summer weekdays, winter weekdays and Sundays.When analyzing either the Central Purchased Power

System or the Central Turbopowered Energy Systemthe energy room loads must be added to the basic

shopping-center electric loads. The main energyroom load is, in both systems, the air condition-

ing -- pumps and tower fans. In the case of this

shopping center the following maximum energy room

loads were estimated for the two central systems:

Central On-Site

Purchased Power Turbopowered

System(kw) System(kw)

Winter Energy

Room Load .... 120.............. 160

Summer Energy

Room Load ... 1935 479

Fig.25 depicts the total electric load pro-

files which were estimated for the Central Turbo-

powered Energy System, and Fig.26 shows that esti-

mated for the Central Purchased Power System.

SUMMER WEEKDAYS -

SUNDAYS-\\,_.

- - -

2 4 6 8 10 12 14 16 18 20 22 M

TIME OF DAY, MR

Fig. 25 Estimated electrical load profiles

14


2000

;800

1600

1 400

200

1 000

800

600

400

200

0

TOTAL AIRCONDITIONINGREQUIRED

4r A111,1,- 4 #,AP111

AIR CONDITIONING AVAILABLEFROM EXHAUST HEAT

%.1E

TABLE 3

CENTRAL PLANT UTILITY SYSTEMS

ESTIMATED UTILITY COSTS

Item Description

Annual Electric Consumption

Annual Electric Cost

Annual Gas Fuel Consumption

Annual Gas Fuel Cost

Total Annual Utilities Bill

Maintenance - Annual Cost

Total Annual Operating Cost

Purchased TurbopoweredPower System System

15,412,344 KWH --

5247

53,100 MCF 273,759 MCF

$ 20,642 $ 97,736

$268,269 5 97,736

5 31,896 5 48,235

5300,165 5145,971

Total Capital Costs

Net Capital Costs i

Annual Operating Costs

Using the annual operating cost of the Individual Metered System as

the gross revenue potential for the utilities service and subtracting annual

operating cost of the Turbopowered Energy System gives the net revenue

potential for the utilities service.

$337,283 - $145,971 $151,312/year

If these utilities are sold by a central plant, then the net capital

cost of the Turbopowered Energy System becomes the difference between the

two central plants.

$1,106,212 - 5530,802 - 5575,410

I The Total Capital Costs less ten percent for salvage value at the end oftwenty years service.

Table 4

Economic Summary Sheet

IndividuallyMeteredPur. Power

System

0421,909

5337,283

On-SiteCentral Turbopowered

Purchased EnergyPower System System

5589,780 01,228,124

$530,802 51,106,212

$300,165 $ 145,971

2 6 , 0 , 2 4 6 18 20 22

TIME OF DAY, HR

Fig. 27 Air-conditioning load profiles - turbopoweredenergy system

Annual Electric Bills

Small Stores (26 units - 1,056 ft 2 each)

Medium Stores (20 units - 4,350 ft 2 each)

Large Department Store

Variety Store

Women's Clothes Shop

Department Store

Men's Clothes Shop

Cafeteria

Mall, Parking Lot and Signs

Annual Gas Fuel Cost (One Meter)

Total Annual Utilities Bill

Maintenance - Annual Cost

Total Annual Operating Cost

TABLE 2

INDIVIDUALLY METERED PURCHASED ENERGY SYSTEM

ESTIMATED UTILITY COSTS

Cost

5 16,900

S 46,360

5104,765

6,607

5 6,607

$ 47,155

$ 5,920

5 5,920

5 23,392

S 20,642

5284,268

5 53 , 015

5337,283

The air-conditioning load for the shopping

center was estimated to be 300 sq ft per ton de-

livered. Based on a total air-conditioned area of

516,931 sq ft, a peak load of 1725 tons deliveredto the shopping center is required. The maximum

electric power required from the system is on the

hot days in order to provide the additional power

needed for the air conditioning. The hot days

also cause a reduced peak power available from the

'turbine engines, owing to a decrease in the com-

bustion air density. In the case of this shopping

center, it became more economical to chill the

turbine inlet air to 60 F on the hot summer daysthan to add an additional engine to carry the peakelectrical load. The air-conditioning load for

the inlet air was 21 tons per engine at maximum

load. This results in a peak air-conditioning

load of 1935 tons for the Turbopowered System and1725 tons for the Central Purchased Power System.

The required air-conditioning load profile and theair-conditioning profile available from the exhaust

heat are shown in Fig.27. The difference between

these two profiles (shaded portion) is the amount

of air conditioning which must be supplied through

auxiliary firing. In this case, the auxiliary

firing will require a maximum demand of 11,670std. cu ft per hour of natural gas (with LHV of

1000 Btu/std. cu ft) with a total daily consump-

tion of 119,200 std. cu ft.The daily fuel consumption by the turbine

engines was calculated to be:Summer Weekday: 818.1 MCF

Winter Weekday: 747.6 MCF

Sunday: 227.4 MCF

The results of the operating costs for the

three systems under consideration are shown in

Tables 2, 3 and 4.

15


TABLE 5

GARRETT ENERGY SYSTEMS

tioning and most of the lighting load would have

to be dropped in the event of a power failure.OWNER LOCATION APPLICATION NO. OPER, REMARKS By contrast, the On-Site Turbopowered EnergyConsumers Power Co. Royal Oak, Mich. Service Center

TUR. HRS.—

24,000 Standard Total Energy System has adequate standby power to enable thisSo. Cal,. Gas Co.Gas PavilionAriz. Public Service Co.

Torrance, Calif.World's Fair, N.Y.Phoenix, Arizona

IndustrialExhibitIndustrial

22,000

8.80012,000

60 Cyc. and 420 Cyc. PowerStandard Total EnergyBlock Loaded to Ariz. Power system to handle 100 percent of the peak summer

Nor. Nat. Gas Co. Hobbs, New Mexico Processing Plant 7,000 Block Loaded [0 N. 0eX. Posey

Nor. III. Gas Co. Glen Ellyn, III. Service Center 31,334 60 Cyc. and 420 Cyc. Power demand, losing no air conditioning in the event ofSo. Coun. Gas Co.ich. Con. Gas Co.

David Wil l 1 ,115

Anaheim, Calif.Grand Rapids, Mich.Coral Gables, Fla.

Service CenterService CenterApartment Hotel

16,5006,300

23,000

Standard Total EnergyStandard Total EnergyStandard Total Energy an unscheduled shutdown of any of the turbine gen-

0 Patten Tractor Co.1 Elizabethtown Gas Co.2 Union Gas Co. of Can.

Waukegan, IllinoisElizabethtown, N. J.Chatham, Ont.

Office Bldg.Office Bldg.Office Bldg.

4,80015,5004,000

Parallel with Reels. EngineStandard Total EnergyStandard Total Energy erator modules.

3 Sawyer Invest. Co. Salt Lake City, Utah High Rise Apt. 7,087 Standard Total Energy4 Mggntain fuel Supply5 Arizona Pub. Serv. Co.

Salt Lake City, UtahPhoenix, Arizona

Service CenterIndustrial

0,870tai

Standard Total Energy450-Ton Turbo-Chiller

6 San Sebastian Dev. Co.7 San Sebastian Dev. Co.

El Segundo, Calif.Pasadena, California

Office Bldg.Office Bldg.

2,

s

500stal

Standard Total EnergyStandard Total Energy SPECIFIC APPLICATIONS

8 Brooklyn Union Gas Co. Staten Island, N. Y. Service Center stal Standard Total Energy9 San Sebastian Dev. Co. Torrance, California Shopping Center stal Standard Total Energy0 Davermen AssociatesI Mountain Fuel

Grand Rapids, Mich.Salt Lake City, Utah

Office Bldg.Office Bldg.

stalnstal

Standard Total EnergyStandard Total Energy

2 N. V. Nederlandse Gasunie Holland Office Bldg. stal Standard Total Energy Table 5 lists the major Garrett Energy Sys-3 Univ. of Calgary

as of November 1966

Calgary, Alberta School stal Standard Total Energy

tems either presently installed or being installed.

1

It should be understood that the Individual-

ly Metered Purchased Power System contains no em-

ergency standby power capabilities. In the eventof a power failure, the entire shopping center

would be dark, automatic doors would not operate,

elevators would be still, and air-conditioning and

ventilation would cease. This has had a direct

effect on insurance in many instances.

The Central Utility Plant using purchasedpower has standby power capable of operating 24.35percent of the maximum required load. Air condi-

The applications vary from a "show-case" installa-

tion at the Worldts Fair in New York to a remoteprocessing plant in New Mexico, and from high-rise

apartments to an office building in Holland. The

point is that these small Turbopowered Generator

Modules are being applied anywhere and everywhere

a suitable rate differential exists between pur-

chased power and fuel, or where an absolutely de-

pendable source of electrical energy must be pro-

vided. Operators of hospitals, computers, specif-

ic types of processing plants, and even drilling

rigs are rapidly becoming aware of. the advantages

offered by on-site turbopowered energy systems.

16


Documents

Aieseac Eegy Sysems Aicaios o e 8 Seies Gas uiesproceedings.asmedigitalcollection.asme.org/data/Conferences/ASMEP/...uie egie, coos, a imay gea euc io. Cuaway iews o e gasuee a iqui