15 MW CAES Plant with Above Ground Storage – Distributed Generation15 MW CAES Plant with Above Ground Storage – Distributed Generationbased on based on

Novel Concepts Developed by ESPCNovel Concepts Developed by ESPC

Project Sponsored by Project Sponsored by EPRIEPRI

Presented by Presented by

Dr. Michael Nakhamkin, Dr. Michael Nakhamkin, Energy Storage and Power CorporationEnergy Storage and Power Corporation

Presentation

• The 110 MW CAES Project for Alabama Electric Cooperative:

– Concept, Design, Engineering, Operations– Lessons learned

• 15 MW CAES Plant with Above ground Storage:– Heat and Mass Balances– P&IDs– Lay Out drawings– Capital Cost Estimate– Summary

The CAES TechnologyThe 110 MW CAES Project

Alabama Electric Cooperative

Gross Power = 191 MWHeat Rate = 9,350 Btu/kWh

General Electric 7FA CT Performance at Different Ambient Temperatures at Sea Level

GCFuelAmbient

Air

T 0

T 2562

T 1079M 1083

P 250

195 MW

T 713

M 1060

0 F

390 MW Ambient Temperature

Gross Power = 150 MWHeat Rate = 9,760 Btu/kWh

GCFuelAmbient

Air

T 95

T 2562

T 1141M 935

P 214

171.1 MW

T 812

M 898

95 F

324.6 MW Ambient Temperature

Gross Power = 172 MWHeat Rate = 9,360 Btu/kWh

GCFuelAmbient

Air

T 59

T 2562

T 1116M 984

P 228

173.4 MW

T 749

M 963

59 F - ISO

348.7 MW Ambient Temperature

Simplified Schematic of CAES Plant

Stores Wind Energy in the Form of Compressed Air

Compressors Power Generating Expanders

Recuperator

Combustors

Off-Peak Wind/Renewable Energy

Motor Generator

Peak Power Energy

Underground Storage

CAES Technology Features

CAES technology was developed as a load management plant with the prime purposes:• To store the off-peak energy that is not needed and inexpensive

and to increase load factor of base-load plants (Coal, Nuclear)• To release this energy during peak hours when energy is needed and the price is high

• The AEC’s 110MW CAES Project had been driven by two factors:– Due to very low off peak loads, two 300 MW coal-fired plants during off-peak hours

operated at very low loads with extremely high heat rates and sometimes had been shot down

– AEC had shortage of peak power

• Project met all performance guarantees, costs and schedule and in successful operation for over 17 years.

• Q: Why there were no other up w. CAES Plants built?• A: New Technology and No big motivations then cost of NG was then $2/M BTU and Coal

$1.5/M Btu

• The current development of Wind Power- the primarily uncontrollable energy source- requires the CAES plants to store wind energy produced during off-peak hours and distribute it with additional benefits during peak hours when energy is needed and cost of energy is high

• Now NG Cost is $10/M Btu and possibly will go up.

Alabama Compressed Air Energy Storage PlantPeak Power 110 MW; 26 hrs of continuous Power Generation;

Heat rate is 4000 Btu/kWh; Off-Peak Power 51MW, Capital Cost $600/kW

Schematic for AEC CAES Plant (110 MW – 26 Hour)

CAES Concept and Parameters developed & specified by ESPC; Compressors &Expanders delivered by DR;

Recuperator by SW; HP/lP Combustors by AITUnderground Storage- PB

FuelAfter-cooler

Compressors (50 MW)

LP HP

Expanders (110 MW)

HP IP-2 IP-1 LP LP HP

Intercoolers

SSS Clutches

Ambient Air

Underground Storage Cavern: A Solution Mined Salt Cavern

Motor/Gen

Recuperator

Heat RateEnergy Ratio

41000.81

Exhaust Stack

Salt Cavern Air Store:Distance to Surface = 1500 ftHeight = 1000 ftAvg. Diameter = 156 ftVolume = 22MCF

Pressure = 650 psi

Alabama Electric Cooperative CAES Plant: 110 MW Turbomachinery Hall

From Left to Right: Compressors, Clutch, Motor-Generator and Expansion Turbine

The 110 MW CAES Plant Engineering, Optimization and Delivery

ESPC developed, optimized and specified the 110 MW CAES plant concept based on available and/or newly developed components provided by various suppliers:

The reheat, intercooled and recuperated turbomachinery is based on:• Compressors and expanders provided by Dresser Rand• HP and LP combustors provided by AIT • Advanced Recuperator provided by Struthers Well (patented by ESPC)• Underground Storage by Parsons Brinkerhoff• Control philosophy for operation and Safety

ESPC was conducting technical supervision of the project execution including:• Supervision of the turbomachinery development by Dresser Rand• Supervision of the HP combustors development by AIT• Development of the test procedures• Supervised performance guarantee tests and issued the Test Report• Under contract with EPRI, ESPC recorded key plant parameters during 1991-1994 -three

years after the project commercialization, and issued “ Value Engineering” Report

EPRI was Co-sponsor of the CAES Project Concentrating on R&D Issues:Turbomachinery, Advanced Recuperator, Project Technical Supervision, the LP Expander TIT Increase

Ground Breaking Ceremony ESPC Received EPRI’s Dr. R. Schainker, EPRI Achievement Award Ray Claussen, AEC, VP Operations, PlanningDr. M. Nakhamkin, ESPC

Unique Features and Components of the AEC’s Turbomachinery/Plant

The multi-component single-shaft turbomachinery train has the first of the kind unique features and unique components- all optimized and developed during the project execution:• Reheat expander train with HP/LP combustors• Intercooled Compressor train• Advanced Recuperator• Turbo expander and compressor trains are integrated with the underground storage• Control Philosophy- Power Control by both HP/LP fuel and air flows

First of the kind Components with only single applications:

Dresser Rand:– HP steam turbine converted into the expander and integrated with the HP combustors– The industrial expander with increased TIT from 1350F to 1500 F that required the first

time applied by DR nozzles cooling• AIT:

– Developed unique HP combustor (800 p.s.i.a and 1000F) uniquely operating at variable airflow– Newly developed LP combustor (200 p.s.i.a 1600F) uniquely operating at variable airflow

• Struthers Wells:– Advanced Recuperator

Lessons LearnedSummarized in the published by EPRI’s “Value Engineering” report (produced by ESPC)

The 110 ME CAES project (with first of the kind unique features and unique components)- is unquestionably successful- It met all performance guarantees, schedule and budget.

There are lessons learned:

The single-shaft turbomachinery train with multiple (9) components has some operationaland maintenance complicationsConclusions: the separate components approach would provide operational and maintenanceadvantages

First of the kind components specifically developed for the CAES turbomachinery had a very limited power generation experience and had no operational and maintenance manuals for

Conclusions: use of off-shelf /standard components will resolve this issues.

The novel HP/LP combustors:• Had no operational and maintenance manuals based on experience • The HP combustor has inherently very high NOx emissions (app. 70 p.p.m.v.)• The LP combustor is customized for this train and has higher than CTs NOx emissions Conclusions: • Novel HP/LP combustors should be avoided• It is better to burn fuel in DLN combustors developed by OEMs

Single compressor train has limitation on use of available off-peak powerConclusions: Multiple compressors provide operational and maintenance advantages

15 MW CAES Plant with Above Ground Storagebased on Novel CAES Plant Concepts

Developed & Patented by ESPC

CAES Plant Power:– 30% of power generated by a Combustion Turbine–70% Green Power is generated by Air Expanders utilizing the stored (operating w/o combustors and utilizing the CT exhaust gas heat - the air bottoming cycle (similar to steam bottoming cycle for CC plants)

–The Overall heat rate is approximately 4000 Btu/kWh (vs. 10,000-11,000 by CTs)

The fuel is burned only in CT’s combustors (there is no additional fuel burners/combustors)

The storage is pressurized by multiple stand-alone off-shelf motor driven compressors

Significantly lower capital costs due to:– Use of standard components–No new components–Simple construction & tuning up

Schedule time is within two years

The storage size is significantly reduced with associated storage costs

15 MW CAES Plant with Air Injection and Bottoming Cycle Based on Taurus 60

Major components: CT, multiple Compressors; Recuperator; HP&LP Expanders

44.05 F14.7 PSIA

42 Lb/s

609.3 F101.8 F 290.5 PSIA 6.148 MW412.6 PSIA 60.04 MBTU/Hr 5 Lb/s24.59 Lb/s 0.775 Lb/s Air Injection

3.716 MW6.937 MW 900 F

90 F 173.814.7 PSIA

25 Lb/s 954 F14.7 PSIA

5.929 MW Gross GT 49 Lb/s10127 BTU/kWhr Gross LHV Heat Rate

444 F1530 PSIA 90 F24.59 Lb/s 800 PSIA

47 Lb/s 15.19 MW Net Total Power3953 BTU/kWhr Net LHV Heat Rate

Exhaust

Air

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

Fuel HP Expander

~~

~

LP Expander

CTs Performance vs. Ambient TemperaturesGER 3567H

PG7241FA with DLN (150.4 MW @ 95°F)

Humid Air Injection:Measured:• 18.3 MW increase @ 3.5% humidity, 95°F ambientPredicted:• 26.6 MW increase @ 5.5% humidity,

NOX:

• 9 ppm with DLN combustor

• 12 ppm with steam injection and DLN

• < 9 ppm with HAI and DLN

: During testing there were no known operational limits that were exceeded. Specifically, during the testing all vibration, compressor (7241 Limits), emissions, combustion dynamics and generator temperature

limits were not exceeded…The test criteria were met ”.

Calpine Broad River ProjectWhere AI Validation Tests Conducted

CAES Plant Power consist of 5.2 MW of CT Power and 10.6 MW Green Power

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

11000

Pla

nt

En

erg

y B

TU

Performance of CT & CAES Plants

Energy(1.7 kW)

CT CAES CT CAES CT CAES

Total CAES Energy 3,0 kWh (10,200 Btu)

CT Energy 1kWh (3412 Btu)

CT HR 10,000 Bru/kWh

CAES HR 3700 Btu/kWh

Green CAES Energy2 kWh (6800 Btu)

1 kWh of Stored Off-peak Energy Returns 0.78 kWh of Peak Energy

-1.25

-1

-0.75

-0.5

-0.25

0

0.25

0.5

0.75

1En

ergy

Rel

ease

kW

Ener

gy P

rodu

ced

kWWin

d E

ner

gy

Effectiveness of Wind Energy

Off-peak 1 kWh

Green peak 0.78 kWh

CAES Plant Heat Rate vs. Load

3750

3800

3850

3900

3950

4000

4050

4100

4150

60 65 70 75 80 85 90 95 100

Plant Load %

Hea

t R

ate B

TU

/Kw

hr

CAES Plant with Air Injection and Bottoming Cycle Based on GE 7B CT

Major components: CT, Multiple Compressors; Recuperator; HP&LP Expanders60.68 F14.7 PSIA440 Lb/s

665.5 MBTU/Hr 528 F86 F 8.591 Lb/s 206.4 PSIA 52.96 MW

14.7 PSIA 60 Lb/s497.1 Lb/s Air Injection

50.3 MW94.13 MW 900 F

86 F 222.6 F14.7 PSIA333 Lb/s

66.91 MW Gross 9945 BTU/kWhr Gross LHV HR

102 F1450 PSIA

327.9 Lb/s95 F

800 PSIA500 Lb/s

166.46 MW Net Total Power3997.8 BTU/kWhr Net LHV Heat Rate

Exhaust

Air

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelHP Expander

~~

~

LP Expander

15 MW CAES Plant with Bottoming Cycle and Inlet Chilling

Based on Taurus 60

Major Components: CT; Multiple Compressors; Expander; Recuperator; Compressed Air Storage

44.7 F14.7 PSIA

47 Lb/s

9.008 MW44.7 F14.7 PSIA 63.47 MMBTU/hr LHV

47 Lb/s 0.819 lb/s Fuel6.937 MW 800 F

90 F 268.9 F14.7 PSIA

25 Lb/s 960.7 F14.7 PSIA

5.814 GT Generator MW 48.49 Lb/s10916.9 Gross LHV BTU/kWhr

102 F1500 PSIA 90 F

24.56 Lb/s 800 PSIA47 Lb/s 14.52 MW Net Total Power

4373 BTU/kWhr Net LHV Heat Rate

Solar Torus 60 CAES, Expander & GT Inlet Air Cooling

Exhaust

GT Air

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

Fuel

Expander

~~

~

CAES Plant with Bottoming Cycle and Inlet Chilling Based on GE 7B CT

Major components: CT, Multiple Compressors; Recuperator; Expanders;

Compressed Air Storage44.87F14.7PSIA535Lb/s

44.87F14.7PSIA 683.2MMBTU/hr LHV 111.5MW535Lb/s 8.82lb/s Fuel

96.54MW 850.6F

86 F 200F14.7PSIA356Lb/s

62.86Gross MW 10870Gross LHV BTU/kWhr

102F1450PSIA350.5Lb/s

95 F950PSIA535Lb/s

172.9MW Net Total Power3951BTU/kWhr Net LHV Heat Rate

Exhaust

GT Air

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelExpander

~~

~44.87F14.7PSIA535Lb/s

44.87F14.7PSIA 683.2MMBTU/hr LHV 111.5MW535Lb/s 8.82lb/s Fuel

96.54MW 850.6F

86 F 200F14.7PSIA356Lb/s

62.86Gross MW 10870Gross LHV BTU/kWhr

102F1450PSIA350.5Lb/s

95 F950PSIA535Lb/s

172.9MW Net Total Power3951BTU/kWhr Net LHV Heat Rate

Exhaust

GT Air

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelExpander

~~

~

15 MW CAES w. Above Ground Storage P$ID

Expander Stack

CT Inlet Flow Controller

HV1Compressor Controller

4' Air DuctGT Controller

Isolation DamperAmbient Air Expander Recuperator Controller4' Air Duct

CAES Controller HV6

Expander ControllerExpander Controller Fuel HV6 6"

Comp Controller Recuperator Controller12"

To GT Stack

Recuperator

Plant DCS Vent CAES Controller

GT ControllerSRV4

Expander ControllerSRV7

Blow-Off 9"Expander Controller

LP Comp Skid 2, 3, & 4

HV1

3"6"

3"CV1 HV2 HV3

Blow-Off

HV1

LP Comp 2, 3, 4CWR2

8"CWS2 CV2 HV4 HV5

LP Comp 2, 3, 4

GT Controller Expander Controller

LP Comp 1-4 Controllers Recuperator ControllerCooling Water Return Interface

Cooling Water Supply Interface HP Comp Controller Plant DCS

Eng:Dwg#: Rev A Date: 04/20/08

M Chiruvolu

15 MW CAES PlantTypical P&ID for CAES-Plant

Based on Taurus 60 - Bottoming Cycle & Inlet Chilling

CAES15-CL-1

LP Compressor Skid 1

OIL SKID

PIT 4

CAES MASTERCONTROLLER

FE7

PT 7

FT 7 ~MHV12

TIT 4

TIT 9

MPCV 4

TIT 6

TC 6 PT 6 PI 6

EXPAN

DER

C

ON

TRO

LLER R

ECU

PERA

TOR

C

ON

TRO

LLER

LP COMP 1 CONTROLLER

M

HV 3

TE 2

TI 2

TE 2

TI 2

PCV1 FT 2

PT 2 PI 2

Gas Turbine

~

M

HV 9

GT CONTROLLER

MFV 5

FE9

PT 9

FT 9

MHV8

M HCV 5

CAES Storage

HP Compressor Skid

OIL SKID

HP COMP CONTROLLER

M

HV 5

TE 2

TI 2

TE 2

TI 2

PCV2 FT 2

PT 2 PI 2

15 MW CAES w. Above Ground Storage Lay Out Drwg

Summary Table of Performance Estimates(w/o specific optimization)

Description of Item Air Injection Inlet Cooling

Civil/Architecture Site, Clearing & Grubbing 60,000 60,000

Fence 440 LF w/2gates 6,600 6,600 Slab on Grade w/ 2' Haunches 80,750 80,750

Compressor Slabs (X4) 9,500 9,500 Control & Service Building 360,000 360,000

Sub-total 516,850 516,850 Equipment Costs

Combustion Turbine 2,600,000 2,600,000 LP Air Compressor 1,400,000 1,400,000

HP Compressor 450,000 450,000 Heat Exchangers 950,000 950,000

HP Expander 484,000 1,000,000 LP Expander 727,000 -

Compressed air Storage 5,200,000 5,200,000 Sub-total 11,811,000 11,600,000

Mechanical (installation)

Combustion Turbine 750,000 750,000 LP Air Compressor 150,000 150,000

HP Compressor 50,000 50,000 Heat Exchangers 225,000 225,000

HP Expander 125,000 300,000 LP Expander 250,000 - 8" Steel Pipe 30,000 30,000

Sub-total 1,580,000 1,505,000 Electrical and Controls

Misc. Electrical 100,000 100,000 Field Mounted Instruments 150,000 150,000

Sub-total 250,000 250,000 Indirect Costs

Engineering and Management 1,200,000 1,200,000 Start Up & Commissioning 100,000 100,000

Contingency 750,000 750,000 Construction Overhead etc. 750,000 750,000

EPC Contractor Profit 1,500,000 1,500,000 Licensing Fee 125,000 125,000

Sub-total 4,425,000 4,425,000

Total Capital Cost 18,583,000 $18,297,000

Major performance characteristics of the 15 MW CAES/AI/ Expander concept can be summarized as follows:

• The total CAES plant power is 15.2 MW and includes the power of the Taurus 60 combustion turbine (augmented by the injected stored air) plus the additional power produced by HP and LP expanders utilizing the preheated stored air. The heat rate is 3960 Btu/kWh.

• The CAES plant has two major power generation components:– The Taurus CT generating of approximately 5.2 MW (at 90F ambient temperature) with heat

rate of approximately 12,000 Btu/kWh and – The green (w/o fuel consumption) CAES power is the 10.6 MW that is the sum of

approximately 9.9 MW, generated by HP and LP expanders plus the CT power augmentation by approximately 0.72 MW due to air injection.

• The off-peak energy storage:– The stored off-peak energy of 13.8MWh results in total generation of 15.2 MWh of peak energy,

i.e. energy ratio is approximately 0.91 – The stored off-peak energy of 13.8MWh results in generation of 10.6 MWh of green peak

energy, i.e. energy ratio is approximately1.3 or 1 kWh of the stored off peak energy generates 0.77 kWh of peak energy w/o using fuel.

• Above ground energy storage is sized for two hours of the continuous peak power generation:– Total energy generated is 30.4 MWh– Total energy stored 27.6 MWh

• Specific costs for this concept are $1200-1300/kW

Comparative Analysis of Generation Costsfor

Coal. CT, CC and CAES plants

Peaking Power Generation Options Comparison Fuel Price @ $10 per MM BTU Gas (Coal $2)

25

50

75

100

125

150

175

200

225

250

275

300

325

350

375

400

425

0 10 20 30 40 50 60

Capacity Factor (%)

Coal CT CTCC CAES 15MW

ESPC with its subcontractors is delivering CAES projects on EPC basis.Estimated specific costs of the overall project including underground storage is approximately $550-600/kW. Delivery time is approximately 24 months, primarily controlled by a combustion

turbine deliveryThese concepts are based on various combinations of the major standard /off – shelf components-existing or new combustion turbines, air compressors, air expanders and heat recovery recuperator –all integrated with a compressed air storage and engineered for specific operational,economic and geological conditions.

As it relates to the selection of a combustion turbine, customers have a choice of selection a combustion turbine based on their preferences and ESPC will design/engineer the CAES plantbased on the selected combustion turbine. These h&m balances are based on GE7FA, GE 7EAand GE 7B CTs for 400 MW, 300 MW and 150 CAES plants respectively

Suppliers of Off-Combustion Turbine standard components include but not limited to:Air Compressors: MAN Turbo, Dresser-Rand, and Ingersoll-RandTurbo-Expanders: Major OEM’s with IP back pressure steam turbine technology; MAN Turbo,

Skoda, Atlas Copco, and HitachiRecuperator: RGP Engineering, Nooter/Eriksen, Deltech, and BHEL

ESPC has a number of qualified EPC contractors for delivery of CAES projects with typicalwarranties and guaranties and with typical commercial terms.

Technology Offerings• ESPC offers the Power Augmentation - AI and CAES

technology for licensing.

• ESPC delivers the AI and CAES projects on turn-key basis with typical performance guarantees

• ESPC is flexible to cooperate with Customers in delivery the AI and CAES projects.

• Discussion of program

Business contacts- Dr. Michael Nakhamkin [mnakhamkin@espcinc.com]