Novel Compressed Air Energy Storage ConceptsDeveloped by ESPC

Presented to

EESATMay 2007

Presented by Presented by

Dr. Michael Nakhamkin, Dr. Michael Nakhamkin, Energy Storage and Power Energy Storage and Power Consultants, LLCConsultants, LLC

Presentation

• ESPC involvement in the 110 MW CAES Project for AEC

• Developed by ESPC CAES Plant Concepts as Applied to GE 7241 CTs

CAES Technology

ESPC involvement in the 110 MW CAES Project for AEC

CAES Technology Features

CAES technology was developed as a load management plant with the prime purposes:

• to increase load factor of base-load plants (Coal, Nuclear) during off-peak hoursstore the off peak power during

• Utilize is 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 load with extremely high heat rate and sometimes had been shot down

– AEC had shortage of peak power purchased from SCS

• 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.

Fundamentals of the AI technology

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

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

ESPC’s Role in the AEC CAES ProjectThe only Operating CAES Power Plant

ESPC developed the 110 MW CAES plant concept based on available off-shelf components including:

• The reheat, Intercooled and recuperated turbomachinery based on available Dresser Rand compressor and expander standard components

• Storage parameters• Control philosophy for operation and Safety• Advanced Recuperator

ESPC was conducting Technical Supervision of the Project 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

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

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

Unique Features of the AEC’s turbomachinery

The CT Plant with

– Reheat expander

– Intercooled Compressor train

– Advanced Recuperator

– Power Control by both fuel and air flows

AEC 110 MW – 26 Hour CAES Plant (Commercial Operation 5/31/91)

AEC CAES Plant (McIntosh, Alabama):

AEC CAES Plant (McIntosh, Alabama): - - Arial View - -

AEC McIntosh Site: CAES Plant On Right and Two Combustion Turbines On Left

Geologic Formations Potentially Suitable for CAES Plants That Use Underground Storage

CAES Air Storage Reservoir: McIntosh Alabama Salt Cavern

Cavern Characteristics- Volume ~ 22M cubic ft.

- Distance from Surface to Top of Cavern ~ 1500 ft.

- Distance from Surface to Bottom of Cavern ~ 2500 ft.

- Average Diameter of Cavern ~ 270 ft.

- Average Wall Temperature ~ 60F

Cavern Wellhead at AEC CAES Salt Cavern

Alabama Electric Cooperative CAES Plant: 110 MW Turbomachinery Hall

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

CAES Plant ConceptsDeveloped & Patented by ESPC

with examples demonstrated based onGE 7FA Combustion Turbines

Advantages of Novel concepts

• The CAES concept for AEC was based on the turbomachinery developed and customized by ESPC using various compressor, expander, combustor, recuperator, etc. components

• It resulted in increased costs, longer schedule with extensive and expensive tuning up efforts.

• Novel Concepts are:– Simple and based on standard combustion turbine– CAES technology is external to the CT and is based on the air

bottoming cycle (similar to steam bottoming cycle for CC plants)– They have significantly lower capital costs without any additional

fuel burners/combustors– Schedule time is within two years– The storage size is significantly reduced with associated costs

CTs Performance vs. Ambient TemperaturesGER 3567H

GE 7241CT Performance(no storage, no injection)

1.613E+09 kJ/hr LHV Heat Input 8.96 kg/sec Fuel

35.0 C20.00 bar

0.0 kg/sec

0.0 MW

30.0 C1.01 bar

0.0 kg/sec

30.0 C 613.8 C1.01 bar 159.8 MW 1.01 bar

421.0 kg/sec 10,094 kJ/kWh r 429.9 kg/sec

35.0 C40.00 bar

164.6 C 0.0 kg/sec65.00 bar 159.8 MW T otal Power

0.0 kg/sec 10,094 kJ/kWh r Heat Rate

ExhaustAir

Power Product ion Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelAir Injection

CAES-AI Plant Based on GE 7241CT1.710E+09 kJ/hr LHV Heat Input

9.50 kg/sec Fuel

486.6 C20.00 bar

50.0 kg/sec

29.1 MW

30.0 C1.01 bar50.0 kg/sec

30.0 C 586.6 C1.01 bar 193.1 MW 1.01 bar

421.0 kg/sec 8,854 kJ/kWh r 480.5 kg/sec

35.0 C40.00 bar

164.6 C 50.0 kg/sec65.00 bar 193.1 MW T otal Power

50.0 kg/sec 8,854 kJ/kWh r Heat Rate

ExhaustAir

Power Product ion Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelAir Injection

CAES-AI Based on GE 7241 with Expander

1.744E+09 kJ/hr LHV Heat Input 9.69 kg/sec Fuel

327.0 C20.00 bar 8.6 MW

50.0 kg/sec

30.3 MW 486.9 C

30.0 C1.01 bar 545.0 C50.0 kg/sec

30.0 C 586.9 C1.01 bar 193.5 MW 1.01 bar

421.0 kg/sec 9,013 kJ/kWh r 480.6 kg/sec

35.0 C54.00 bar

187.7 C 50.0 kg/sec77.00 bar 202.1 MW T otal Power

50.0 kg/sec 8,631 kJ/kWh r Heat Rate

ExhaustAir

Power Production Mode

Compressed Air

Compressor

Gas Turbi ne

Motor

Storage

Air

IntercoolersRecuperator

FuelAir Injection Expander

CAES-AI Based on GE 7241with Bottoming Cycle

19.5 C1.00 bar

475.0 kg/sec

149.5 MW

327.0 C20.00 bar

1.744E+09 kJ/hr LHV Heat Input 525.0 kg/sec9.69 kg/sec Fuel

327.0 C20.00 bar 89.9 MW

50.0 kg/sec

318.3 MW 486.9 C

30.0 C1.01 bar 124.8 C

525.0 kg/sec

30.0 C 586.9 C1.01 bar 193.5 MW 1.01 bar

421.0 kg/sec 9,015 kJ/kWh r 480.6 kg/sec

35.0 C54.00 bar

187.7 C 525.0 kg/sec77.00 bar 432.9 MW T otal Power525.0 kg/sec 4,029 kJ/kWh r Heat Rate

ExhaustAir

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelAir Injection HP Expander

LP Expander

CAES-AI with Bottoming Cycle & Inlet Chilling

16.1 C1.00 bar

1.716E+09 kJ/hr LHV Heat Input 500.0 kg/sec9.53 kg/sec Fuel

253.2 MW

297.6 MW 502.4 C

35.0 C1.01 bar 117.9 C

475.0 kg/sec

15.0 C 602.4 C1.01 bar 174.0 MW 1.01 bar

444.4 kg/sec 9,863 kJ/kWh r 454.0 kg/sec

35.0 C74.00 bar

207.2 C 500.0 kg/sec87.00 bar 427.2 MW T otal Power475.0 kg/sec 4,018 kJ/kWh r Heat Rate

ExhaustAir

Power Production Mode

Compressed Air

Compressor

Gas Turbine

Motor

Storage

Air

IntercoolersRecuperator

FuelExpander

CAES Based on GE 7241with Bottoming Cycle

30.1 C1.615E+09 kJ/hr LHV Heat Input 1.00 bar

8.97 kg/sec Fuel 475.0 kg/sec

240.1 MW

288.0 MW 514.4 C

30.0 C1.01 bar 120.0 C

475.0 kg/sec

30.0 C 614.4 C1.01 bar 160.1 MW 1.01 bar

421.0 kg/sec 10,090 kJ/kWh r 429.9 kg/sec

35.0 C64.00 bar

187.7 C 475.0 kg/sec77.00 bar 400.1 MW T otal Power475.0 kg/sec 4,036 kJ/kWh r Heat Rate

ExhaustAir

Power Production Mode

Compressed Air

Compressor

Gas Turbi ne

Motor

Storage

Air

IntercoolersRecuperator

Fuel Expander

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

1.20.60.50.60.60.51.0Simplicity

1700700700700375327900Appr. Specific Capital Costs, $/kW

1.51.351.35 1.40.851.081.0Relative Cavern Volume

7.56.76.756.94.35.45.0Specific Air Consump. Kg/kWh

0401838994029863188544185Total Power Fuel Related HR, kJ/kWh

04000490319030304000CAES Power related Heat Rate, kJ/kWh

96300288318302981Off-Peak Comp. Power, MW

722572402724233110CAES Power, MW

72427400433202193110Total Power, MW

AdiabaticCAES-AI w. Expander & Inlet Chilling

CAES & Expander

CAES-AI & HP and LP Expander

CAES-AI & HP Expander

CAES-AICAES Conven.

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 5 10 15 20 25 30 35 40

Capacity Factor (%)

Cos

t ($/

kW-Y

r)

Coal CT CTCC CAES

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]Website: www.espcinc.com

Typical Injections into CT/CC Plants