Cost-Effectiveness of Flexible Carbon Capture and Sequestration for Complying with the Clean Power Plan Michael Craig Advisers: Paulina Jaramillo, Haibo

Cost-Effectiveness of Flexible Carbon Capture and Sequestration for

Complying with the Clean Power Plan

Michael CraigAdvisers: Paulina Jaramillo, Haibo Zhai, and Kelly Klima

USAEE Conference, Pittsburgh, PAOctober 26, 2015

2

Outline

• Background• Clean Power Plan• Flexible Carbon Capture and Sequestration

• Methods• Power system modeling• Flexible CCS modeling

• Initial Results• Conclusions and Policy Implications• Future Work

3

Clean Power Plan

• Limits CO2 emissions from existing fossil-fired generators (Final Rule, 1507-1542)

• Less coal-fired generation, more NGCC and renewable generation

• States choose compliance strategy • Type of standard (Final Rule, 882-884)

• Plan type (Final Rule, 879-880)

• Single vs. multi-state (Final Rule, 880-881)

• 1 compliance option: carbon capture and sequestration (CCS) retrofit (Final Rule, 34857)

• Little research on alternative compliance strategies with CPP (ISOMAP)

4

Normal and Flexible CCS

• Continuous operation by normal CCS unit:• Reduces CO2 emissions rate• Reduces net capacity, net efficiency, and ramp rate

5

Flexible CCS differs from normal CCS by including venting and solvent storage components.• Venting: bypass CO2 capture system• Solvent storage: store some rich and lean solvent in tanks

• Stored solvent displaces continuously regenerated solvent• Charging: regenerate stored lean solvent• Discharging: generate electricity using stored lean solvent

6

Normal and Flexible CCS

• Continuous operation by normal CCS unit:• Reduces CO2 emissions rate• Reduces net capacity, net efficiency, and ramp rate

• Venting by flexible CCS unit (relative to CCS unit):• Increases CO2 emissions rate• Increases net capacity, net efficiency, and ramp rate

• Discharging stored solvent by flexible CCS unit (relative to CCS unit):• Maintains post-CCS CO2 emissions rate• Increases net capacity, net efficiency, and ramp rate• Requires stored lean solvent

7

Why Flexible CCS?

• May provide system-wide benefits (van der Wijk et al. 2014, Cohen et al. 2013, Cohen et al. 2012, Delarue et al. 2012, Chalmers and Gibbins 2007)

• Reduce wind curtailment and reserve and dispatch costs

• May be more profitable than normal CCS (Bandyopadhyay and Patiño-Echeverri 2014, Oates et al. 2014, Versteeg et al. 2013, Patiño-Echeverri et al. 2012, Delarue et al. 2012, Ziaii et al. 2009)

• But past papers on system benefits compare flexible CCS to normal CCS (van der Wijk et al. 2014, Cohen et al. 2013, Cohen et al. 2012)

• Not more common CO2 emission reduction technologies

8

Research Motivation and Question

• Little analysis of alternative compliance with CPP• No system comparisons of flexible CCS to wind, re-dispatch, and other

common emissions reductions technologies

• Accounting for system benefits, is flexible CCS a cost-effective compliance strategy with the CPP?

• Compare to normal CCS retrofits, generation at existing NGCC, and new wind• Develop operational model of flexible CCS that can be included in a unit

commitment model

9

Power System Modeling

• Use unit commitment and economic dispatch (UCED) model in PLEXOS

• Co-optimize energy and reserve markets• No transmission constraints

• Build 2030 “base” CPP-compliant fleet• Add wind, normal or flexible CCS to base

fleet to create alternate fleets

• Study region: MISO• Lots of coal and wind resources

Source: amcharts.comSource: misoenergy.org

Left: MISO market area. Right: my modeled region.

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Modeling CPP

• Fleet dispatching effects: CO2 price (Oates et al. 2015)

• 1) Set CO2 price • 2) Apply CO2 price to affected units• 2) Run economic dispatch for year (MATLAB)• 3) Compare affected unit annual emissions to CPP regional mass limit• 4) If emissions > mass limit, increase CO2 price and go back to step 2

• Include final CO2 price in dispatch and reserve costs of affected units

11

Flexible CCS Model

• Develop original set of parameters, generators and constraints to model flexible CCS operations

• Break 1 flexible CCS generator into multiple components in UCED• Estimate parameters via literature review and regressions with IECM data• Couple operations of units with over 35 constraints

• Include flexible CCS model in UCED model• Provides better approximation of operations, costs and emissions

than prior models (van der Wijk et al. 2014.)

12

Flexible CCS Model: Parameter Estimation

• Two methods:• Literature review (van der Wijk et al. 2014, Oates et al. 2014, Versteeg et al. 2013, Cohen et al. 2013, Patiño-

Echeverri et al. 2012, IEAGHG 2012)

• IECM regressions

7000 7500 8000 8500 9000 9500 100000%5%

10%15%20%25%30%35%40%45%50%

f(x) = 6.86086786344904E-05 x − 0.232945257667419R² = 0.969270357417209

f(x) = 7.4943793521862E-05 x − 0.277574820531305R² = 0.967846689423969

SubbitLinear (Subbit)

Pre-CCS Net HR (Btu/kWh)

CCS

Net

HR

Pena

lty (%

)

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Flexible CCS Model: Generators

Base Coal Plant

14

Traditionally, model CCS parasitic load internal to CCS plant.

Base CCS Generator

CO2 Capture System

15

I break out CCS parasitic load as separate component...

Base CCS Generator

CO2 Capture System

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And add separate component for generation while venting...

Base CCS Generator

Venting Generator

CO2 Capture System

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And add separate components for solvent storage…

Base CCS Generator

Venting Generator

Stored Solvent Pump Unit 1

Charging Dummy 1

Discharging Dummy 1

Discharging Dummy 2

Charging Dummy 2


CO2 Capture System

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And add a venting while charging component.

Base CCS Generator

Venting Generator


Charging Dummy 1

Discharging Dummy 1

Discharging Dummy 2

Charging Dummy 2


Venting when Charging Generator

CO2 Capture System

19

Flexible CCS Model: Constraints

• Electricity generation• Solvent flow rate• Offered reserves• Minimum stable load• Ramping• Volume of stored solvent• Units on/off

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Initial Results: Clean Power Plan

0 200 400 600 800 1000 1200 1400 1600 1800 20000

50

100

Carbon Price ($30/ton)

Ele

c. P

rice

($/M

Wh)

Hour of Year

0 200 400 600 800 1000 1200 1400 1600 1800 20000

50

100

No Carbon Price

Ele

c. P

rice

($/M

Wh)

Hour of Year

• CPP increases averageelectricity price butdecreases price variance

• Suggests lower profitabilityof flexible CCS

Jan. 1Day of Year

Mar. 24

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Initial Results: Flexible CCS Model OperationsOperations of 595 MW flexible CCS generator in CPP fleet.

22

Flexible CCS unit generates electricity mostly at base CCS generator, acting like a normal CCS unit.

6/1/2030 6/1/2030 6/2/2030 6/3/2030 6/4/2030 6/5/20300

100

200

300

400

500

600

700

Date

Elec

tric

ity G

ener

ation

(MW

h)

Base CCS

SS DischargeVent

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Solvent storage discharge units mostly provide regulation up reserves.

6/1/2030 6/1/2030 6/2/2030 6/3/2030 6/4/2030 6/5/20300

20

40

60

80

100

120

140

160

180

Date

Reg.

Rai

se R

eser

ve (M

W)

SS Discharge

Base CCS

Vent

24

Solvent storage discharge units also provide raise reserves.

6/1/20306/1/20306/2/20306/3/20306/4/20306/4/20306/5/20300

20

40

60

80

100

120

140

160

180

Date

Rais

e Re

serv

e (M

W)

SS Discharge

Base CCS & Vent

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Pending Results: Cost-Effectiveness of Flexible CCS versus Alternative Compliance Strategies

Compliance Fleet

CO2 Emissions (tons)

Total Operating Costs (Energy + Reserves) ($)

Total Capital Costs ($)

Cost-Effectiveness of CO2 Emissions Reductions ($/ton)

Base (NGCC re-dispatch)Flexible CCSNormal CCSWind

26

Conclusions and Policy Implications

• CPP’s suppression of price variability may reduce profitability of flexible CCS

• Based on analysis so far, value added of flexible CCS is provision of reserves

• Could yield cost savings as reserve requirements increase with wind penetration

• Comparison to normal CCS retrofits, new wind, and existing NGCC fleets will inform attractiveness of flexible CCS as CPP compliance strategy

27

Future Work

• Run normal CCS, flexible CCS, and new wind fleets• Compare emissions and costs

• Run low and high natural gas price scenarios• Compile capital cost data• Calculate break-even flexible CCS capital cost with respect to

alternative CO2 emissions reduction technologies

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Acknowledgements

• Thanks to Paulina Jaramillo, Haibo Zhai and Kelly Klima (CMU)• Thanks to Achievement Rewards for College Scientists, the National

Science Foundation (Grant Number EFRI-1441131) and The Steinbrenner Institute for financial support

• Thanks to Energy Exemplar for academic license

Thanks!Questions?

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Citations• Bandyopadhyay, R., and D. Patiño-Echeverri. (2014). Alternative energy storage for wind power: coal plants with amine-based CCS. Energy Procedia

(63): 7337-7348. • Chalmers, H., and J. Gibbins. (2007). Initial evaluation of the impact of post-combustion capture of carbon dioxide on supercritical pulverized coal

power plant part load performance. Fuel (86): 2109-2123.• Cohen, S. M., et al. (2013). Optimal CO2 capture operation in an advanced electric grid. Energy Procedia (37): 2585–2594.• Cohen, S.M., et al. (2012). Optimizing post-combustion CO2 capture in response to volatile electricity prices. Intl. J. of Greenhouse Gas Control (8): 180-

195. • Delarue, E., P. Martens and W. D’haeseleer. (2012). Market opportunities for power plants with post-combustion carbon capture. Intl. J. of Greenhouse

Gas Control (6): 12-20. • IEAGHG. (2012). Operating Flexibility of Power Plants with CCS. • Fischbeck, P., H. Zhai, and J. Anderson. (2015). ISOMAP: A techno-economic decision support tool for guiding states’ responses to the EPA Clean Power

Plan. Available at http://www.cmu.edu/energy/cleanpowerplantool/• Oates, D.L., and P. Jaramillo. (2015). State cooperation under the EPA’s proposed Clean Power Plan. Electricity Journal (28): 1-15. • Oates, D. L., et al. (2014). Profitability of CCS with flue gas bypass and solvent storage. International Journal of Greenhouse Gas Control (27): 279–288.• Patiño-Echeverri, D., et al. (2012). Reducing the energy penalty costs of postcombustion CCS systems with amine-storage. Environmental Science and

Technology (46): 1243–1252. • U.S. Environmental Protection Agency. “Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility Generating Units; Final

Rule.” [Pre-publication.] Aug. 2015. • U.S. Environmental Protection Agency. Regulatory Impact Analysis for the Clean Power Plan Final Rule. Aug. 2015. • Van der Wijk, P.C., et al. (2014). Benefits of coal-fired power generation with flexible CCS in a future northwest European power system with large scale

wind power. International Journal of Greenhouse Gas Control (28): 216-233. • Versteeg, P., et al. (2013). Cycling coal and natural gas-fired power plants with CCS. Energy Procedia (37): 2676-2683. • Ziaii, S., et al. (2009). Dynamic operation of amine scrubbing in response to electricity demand and pricing. Energy Procedia (1): 4047-4053.

Supporting Slides

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Base CCS Flex CCS, Vent

Flex CCS, SS

0

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Cap

acity

(MW

)


Flex CCS, SS

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CO2

Ems R

ate

(kg/

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h)Base CCS Flex

CCS, Vent

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HR

(MM

Btu/

MW

h)


Flex CCS, SS

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Ram

p Ra

te (M

W/h

r.)

How do CCS and flexibleCCS retrofits affect powerplant characteristics?

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Flex CCS, SS

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acity

(MW

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Flex CCS, SS

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600

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p Ra

te (M

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Coal-fired generatorcharacteristics pre-CCSretrofit.

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Retrofitting CCS reducesCO2 emissions but also reduces net capacity,net heat rate, and ramp rate.


Flex CCS, SS

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Flexible CCS venting eliminates CCS parasiticload and increasesCO2 emissions.


Flex CCS, SS

0

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acity

(MW

)


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CCS, Vent

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(MM

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Flex CCS, SS

0

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Cap

acity

(MW

)


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Ems R

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(MM

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Flexible CCS solvent storagedischarge eliminates CCS parasitic load and maintains CO2 capture rate.

37

Base Fleet Composition

• 1,024 units• 228 coal• 383 natural gas• 22 nuclear• 77 wind• 38 solar

Coal

Natural

Gas

Nuclear

Hydro

Wind

Solar

BiomassMSW

LF Gas

Fwas

te

Non-Fossi

l

Geotherm

al Oil0

10

20

30

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50

60

70

Fuel Type

Inst

alle

d Ca

paci

ty (G

W)

38

UCED Data SourcesData Data SourceGeneration fleet IPM Parsed FileUnit commitment parameters PHORUMHourly plant-specific wind generation profiles

NREL Eastern Wind Dataset

Hourly plant-specific solar generation profiles

NREL Transmission Integration Study

Monthly hydropower capacity capacity factors

EIA Form 923

Demand profile (2030) IPM (hourly profile), CPP (energy efficiency assumption)

Flexible CCS Parameters IECM, literature review

39

UCED FormulationMinimize Total Operating Costs

where:

Subject to:

Supply = demand

Reserves = reserve requirements

Unit-specific max and min load constraints

Unit-specific minimum up time

Unit-specific ramp constraints

TC=total costs; p=electricity generation; OC=operating cost; r=offered reserves; ROS=reserve offer scalar; v=turn on; SU=startup cost; nse=non-served energy; CNSE=cost of nse; HR=heat rate; FC=fuel cost; ER=emissions rate; EC=emissions cost; P=demand; R=reserve requirement; PMAX=max capacity; PMIN=min stable load; u=on/off; w=turn off; MDT=min down time; cUP=ramp up; cDOWN=ramp down; RL=ramp limit

40

Full UCED Formulation

Objective Function: minimize total operating costs

Where:Subject to:

Supply=demand

41

Meet reserve requirement foreach type:

Supplemental reservesmade of spinning and replacement reserves:

Replacement reserves definition:

Provided reserves constrainedby spare reserves:

Provided reserves constrained byoffer quantity:

Spare down reserves constrainedby decrease in generation:

Spare up reserves constrainedby available capacity:

Spare spinning reserveslimited by available capacityand spare regulation reserves:

42

Generation constrained bymax capacity:

Generation constrainedby minimum load:

Definition of ramp up anddown variables:

Limit ramp up values:

Limit ramp down values:

Enforce minimum down time:

Relate on/off to turn on:

Relate turn off to on/off and turn on:

43

Flexible CCS Modeling in Other Papers

Original Coal-Fired Generator

HR = NetHR0

HR = NetHR = NetHR0*(1+HRPCCS)

CCS Retrofit Coal-Fired Generator

Continuous Solvent Regeneration

Retrofit CCS

Venting Generator

Stored Solvent Pump Unit

Constraints Constraints0

20

40

60

80

100

120

Venting or Stored Solvent Generator

Base CCS GeneratorG

ener

ation

(MW

h)

Generation from Base CCS Generator + Added Flexible Units

44

Full Flexible CCS Formulation

45

Flex CCS: Generation Constraints Between Units

𝑝𝐶𝐶𝑆≤𝑃𝑀𝐴𝑋𝐶𝐶𝑆 −

𝐸𝑡𝑜𝐺𝑟𝑖𝑑𝐸𝑡𝑜𝐶𝑂 2𝐶𝑎𝑝𝑡𝑢𝑟𝑒+𝑅𝑒𝑔𝑒𝑛𝑒𝑟𝑎𝑡𝑜𝑟

∗(1+ 𝐸 𝐸𝑥𝑡𝑟𝑎𝐶𝑜𝑛𝑡𝑖𝑛𝑢𝑜𝑢𝑠𝑆𝑜𝑙𝑣𝑒𝑛𝑡𝐸𝑡𝑜𝑆𝑡𝑜𝑟𝑒𝑆𝑜𝑙𝑣𝑒𝑛𝑡 )∗𝑚𝑃𝑢𝑚𝑝1

𝑝𝑆𝑜𝑙𝑣𝑒𝑛𝑡=1

𝐸𝑡𝑜𝐺𝑟𝑖𝑑𝐸𝑡𝑜𝐶𝑂 2𝐶𝑎𝑝𝑡𝑢𝑟𝑒

∗𝑝𝐶𝐶𝑆+𝐸 𝐸𝑥𝑡𝑟𝑎𝐶𝑜𝑛𝑡𝑖𝑛𝑢𝑜𝑢𝑠𝑆𝑜𝑙𝑣𝑒𝑛𝑡

𝐸𝑡𝑜𝑆𝑡𝑜𝑟𝑒𝑆𝑜𝑙𝑣𝑒𝑛𝑡𝑚𝑃𝑢𝑚𝑝1−𝑚𝑃𝑢𝑚𝑝2

𝑝𝑉𝑒𝑛𝑡≤𝑃𝑀𝐴𝑋𝑉𝑒𝑛𝑡 −𝑝𝐶𝐶𝑆∗ 1−𝐶𝑃𝑉𝑒𝑛𝑡

1−𝐶𝑃𝐶𝐶𝑆

𝑝 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒≤𝐸𝑡𝑜𝐺𝑟𝑖𝑑

𝐸𝑡𝑜𝐶𝑂 2𝐶𝑎𝑝𝑡𝑢𝑟𝑒∗ (𝑚𝑃𝑢𝑚𝑝1+𝑚𝑃𝑢𝑚𝑝2 )∗ 𝑃𝑀𝐴𝑋

𝐶𝐶𝑆 −1

𝑃𝑀𝐴𝑋h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒

46

Flex CCS: Generation and Reserve Constraints

𝑟𝐶𝐶𝑆+𝑟𝑉𝑒𝑛𝑡 +𝑟 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒1+𝑟 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒2+𝑟 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑝𝐶𝐶𝑆+𝑝𝑉𝑒𝑛𝑡+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒1+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒 2+𝑝 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑝𝐶𝑜𝑛𝑡𝑆𝑜𝑙𝑣𝑒𝑛𝑡+𝑚𝑃𝑢𝑚𝑝1+𝑚𝑃𝑢𝑚𝑝2≤ 𝑃𝑀𝐴𝑋𝑉𝑒𝑛𝑡

𝑟𝐶𝐶𝑆+𝑟 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑝𝐶𝐶𝑆+𝑝 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒≤𝑃𝑀𝐴𝑋𝐶𝐶𝑆

47

Flex CCS: Solvent Flow Rate and Stored Solvent Volume Constraints

𝑝𝑃𝑢𝑚𝑝 1+𝑚𝑃𝑢𝑚𝑝1+𝑝𝑃𝑢𝑚𝑝2+𝑚𝑃𝑢𝑚𝑝2+𝑝𝐶𝑜𝑛𝑡𝑆𝑜𝑙𝑣𝑒𝑛𝑡≤ 𝑃𝑀𝐴𝑋𝐶𝑜𝑛𝑡𝑆𝑜𝑙𝑣𝑒𝑛𝑡

𝑒𝑣𝐿𝑒𝑎𝑛1+𝑒𝑣𝐿𝑒𝑎𝑛2≤𝐸𝑉 𝑀𝐴𝑋𝐿𝑒𝑎𝑛1

48

Flex CCS: Min Load Constraints

𝑝𝐶𝐶𝑆+𝑝𝐶𝑜𝑛𝑡𝑆𝑜𝑙𝑣𝑒𝑛𝑡+𝑝𝑃𝑢𝑚𝑝𝐷 1+𝑝𝑃𝑢𝑚𝑝𝐷 2+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒1+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒2+𝑝 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑝𝑉𝑒𝑛𝑡≥𝑃𝑀𝐼𝑁 ,𝐵𝑜𝑖𝑙𝑒𝑟𝐶𝐶𝑆

¿

𝑝𝐶𝐶𝑆+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒1+𝑝 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒2+𝑝 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑝𝑉𝑒𝑛𝑡≥ 𝑃𝑀𝐼𝑁 ,𝑆𝑇𝐶𝐶𝑆

49

Flex CCS: Ramping and On/Off Constraints

𝑐𝐶𝐶𝑆+𝑐 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒1+𝑐 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒 2+𝑐𝐶𝑜𝑛𝑡𝑖𝑛𝑢𝑜𝑢𝑠𝑆𝑜𝑙𝑣𝑒𝑛𝑡+𝑐 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑐𝑃𝑢𝑚𝑝𝐷 1+𝑐𝑃𝑢𝑚𝑝𝐷 2+𝑐𝑉𝑒𝑛𝑡≤𝐶𝐶𝐶𝑆

𝑐𝐶𝐶𝑆≤𝐶𝐶𝐶𝑆+(𝑢 h𝑉𝑒𝑛𝑡𝐶 𝑎𝑟𝑔𝑒+𝑢 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒 1+𝑢 h𝐷𝑖𝑠𝑐 𝑎𝑟𝑔𝑒 2+𝑢𝑉𝑒𝑛𝑡 )∗ 𝑃𝑀𝐴𝑋𝐶𝐶𝑆

50

Flex CCS: On/Off Constraints

51

Flex CCS: Reserve Provision Constraints

52

Flexible CCS ParametersUnit Max Power Capacity (MW) Heat Rate

(MMBtu/MWh)Ramp Rate CO2 Emissions Rate

(ton/MWh) [see note 3]

CCS Unit PMAXCCS = PMAX

PreCCS * (1 - CPCCS) [see note 1]

HRCCS = HRGrossCCS [see

note 2]CCCS during normal operations; group constraint applied when vent or discharge generator on.

ERPreCCS * (1-ERRCCS)

Continuous Solvent Unit PMAXSolvent =

PMAXCCS/(EGrid/ECapture)

HRSolvent = HRGrossCCS Only group constraint applied (see

constraints)0

SS Pump 1 Unit PMAXPump1 = (PMAX

CCS-1) / (EGrid/ECapture) / (1 + ECont/EStore)

1 Only group constraint applied (see constraints)

0

SS Pump Dummy 1 Unit PMAXPumpD1 = PMAX

Pump1 HRPumpD1 = HRGrossCCS Only group constraint applied (see

constraints)0

SS Discharge Dummy 1 Unit

PMAXDischarge1 = PMAX

Base * (1 - CPDischarge) HRDischarge1 = HRGrossCCS *

(1 + HRPDischarge)Stored solvent discharging ramp rate (4%/min.), and group constraints

ERPreCCS * (1-ERRCCS) * PCCS / PDischarge1

SS Pump 2 Unit PMAXPump2 = PMAX

Solvent – PMAXPump1 0 Only group constraint applied (see

constraints)0

SS Pump Dummy 2 Unit PMAXPumpD2 = PMAX

Pump2 HRPumpD2 = HRGrossCCS Only group constraint applied (see

constraints)0

SS Discharge Dummy 2 Unit

PMAXDischarge2 = PMAX

Base * (1 – CPDischarge) * PMAX

Pump2 / (PMAXPump1 + PMAX

Pump2)HRDischarge2 = HRGross

CCS * (1 + HRPDischarge)

Solvent discharging ramp rate (4%/min.), and group constraints

ERPreCCS * (1-ERRCCS) * PCCS / PDischarge2

Venting When Charging Unit

PMAXVentCharge = PMAX

CCS HRVentCharge = HRGrossCCS Venting ramp rate (4%/min.), and

group constraintsERBase

Venting Unit PMAXVent = PMAX

Discharge HRVent = HRDischarge Venting ramp rate (4%/min.), and group constraints

ERBase

53

Flexible CCS Parameters: Lit Review vs. IECM

Parameter Estimation MethodSolvent storage tank size Literature ReviewRegenerator size Literature ReviewRamp rate during venting and stored solvent discharging operations Literature Review

Steam turbine minimum stable load Literature ReviewCCS capacity penalty Regression on IECM Results

CCS heat rate penalty Regression on IECM Results

Capacity penalty during full discharge of stored solvent Regression on IECM Results

Heat rate penalty during full discharge of stored solvent Regression on IECM Results

Energy delivered to grid per unit of energy used to capture CO2 during normal CCS operations

Regression on IECM Results

Energy delivered to grid while discharging stored solvent per unit of energy used to store solvent


Energy required for solvent to capture CO2 emissions from fuel used for energy to store solvent per unit of energy used to store solvent


54

Lit Review ParametersParameter Value Used in Our ModelRegenerator size Right-sizedSolvent storage tank size 2 hoursRamp rate during venting and stored solvent discharging operations (as percent of total capacity of venting and stored solvent units)

4% of maximum venting and stored solvent discharging capacity per minute

Steam turbine minimum stable load

30% of maximum capacity

55

7000 7500 8000 8500 9000 9500 100000.00%5.00%

10.00%15.00%20.00%25.00%30.00%35.00%40.00%45.00%50.00%

f(x) = 6.86086786344904E-05 x − 0.232945257667419R² = 0.969270357417209

f(x) = 7.4943793521862E-05 x − 0.277574820531305R² = 0.967846689423969

SubbitLinear (Subbit)Bit


CCS

Net

HR

Pena

lty (%

)

7000 7500 8000 8500 9000 9500 10000

-35.00%

-30.00%

-25.00%

-20.00%

-15.00%

-10.00%

-5.00%

0.00%

f(x) = − 3.70072443795609E-05 x + 0.0557693396402443R² = 0.97899496023403f(x) = − 3.8126323434682E-05 x + 0.0596242511745435

R² = 0.977615674770612



CCS

Capa

city

Pen

alty

(%)

10000 11000 12000 13000 14000 150000.00%0.50%1.00%1.50%2.00%2.50%3.00%3.50%4.00%4.50%5.00%

f(x) = 3.25843839545568E-06 x − 0.0025949728708702R² = 0.980948637377155

f(x) = 3.16212682589337E-06 x − 0.00269276845857734R² = 0.980734283741392

Subbit

CCS Net HR (Btu/kWh)

Net

HR

Pena

lty W

hile

Dis

char

g-in

g St

ored

Lea

n So

lven

t (%

)

10000 11000 12000 13000 14000 15000

-4.50%-4.00%-3.50%

-3.00%-2.50%

-2.00%-1.50%

-1.00%-0.50%0.00%

f(x) = − 3.10993314224103E-06 x + 0.00208295315490609R² = 0.982226214191381f(x) = − 2.97165029638085E-06 x + 0.00160629942347718R² = 0.977199220973694

Subbit

CCS Net HR (Btu/kWh)Ca

paci

ty P

enal

ty W

hile

Dis

-ch

argi

ng S

tore

d Le

an S

olve

nt

(%)

IECM Parameter Regressions

56

IECM Parameter Regressions

10000 11000 12000 13000 14000 150000.000.050.100.150.200.250.300.350.400.45

f(x) = 2.98141408064133E-05 x − 0.0229172817016849R² = 0.991290782582552

f(x) = 2.99516799978839E-05 x − 0.0196303449948082R² = 0.991115314445526

Subbit


Ener

gy F

or E

xtra

Con

tinuo

us

Solv

ent P

er U

nit o

f Ene

rgy

Use

d to

Sto

re S

olve

nt (M

Wh/

MW

h)

10000 11000 12000 13000 14000 150000.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

f(x) = − 0.000270050125172712 x + 5.99079939122409R² = 0.999552320251202f(x) = − 0.000222787207730518 x + 5.35596976745242R² = 0.999645921002792



Net

Ele

ctri

city

to G

rid

Per

Uni

t of

Ene

rgy

Use

d fo

r CO

2 Ca

ptur

e (M

Wh/

MW

h)

10000 11000 12000 13000 14000 150000.000.501.001.502.002.503.003.504.004.50

f(x) = − 0.000271916124438599 x + 6.88236959354894R² = 0.999522716731054f(x) = − 0.000224911857421137 x + 6.2562469315387

R² = 0.999467620641999

SubbitLinear (Subbit)


Net

Ele

ctri

city

to G

rid

Whi

le

Dis

char

ging

Sto

red

Solv

ent P

er

Uni

t of E

nerg

y U

sed

to S

tore

So

lven

t (M

Wh/

MW

h)

57

IECM Regressions: IECM Heat Rates vs. Retrofit Plants Heat Rates

75007700790081008300850087008900910093009500

Bituminous

Plants to Retrofit IECM

Net

HR

Pre-

CCS

(Btu

/kW

h)

7500

8000

8500

9000

9500

10000

Subbituminous

Plants to Retrofit IECM

Net

HR

Pre-

CCS

(Btu

/kW

h)

58

Release from rich storage:

Inflow to rich storage:

Release from lean storage:

Inflow to lean storage:

Volume balance for lean storage:

Pump load constrained bypump capacity:

59

Normal Coal PlantBoilerFuel

(Coal) SteamSteam Turbine Electricity

Flue Gas

Net Electricity to Grid

60

Normal CCS Coal PlantBoilerFuel


Regenerator

Flue Gas

CO2 Absorber

Isolated CO2 Compressor


CO2 Stream for Sequestration

Rich Solvent

Lean Solvent

CO2 Capture System

61

Two key parameters: capacity and net heat rate penalty from CCS retrofit.

BoilerFuel (Coal) Steam

Steam Turbine Electricity

Regenerator

Flue Gas

CO2 Absorber




Rich Solvent

Lean Solvent

CO2 Capture System

62

Flexible CCS Coal Plant: VentingBoilerFuel


Regenerator

Flue Gas

CO2 Absorber




Rich Solvent

Lean Solvent

CO2 Capture System

Vented Flue Gas

63

Venting eliminates parasitic load of CCS system.



Regenerator

Flue Gas

CO2 Absorber




Rich Solvent

Lean Solvent

CO2 Capture System

Vented Flue Gas

64

Key parameters: reduction in CCS capacity and heat rate penalty when venting.



Regenerator

Flue Gas

CO2 Absorber




Rich Solvent

Lean Solvent

CO2 Capture System

Vented Flue Gas

65

Flexible CCS Coal Plant: Stored Solvent



Regenerator

Flue Gas

CO2 Absorber

Lean Solvent Storage Tank

Rich Solvent Storage Tank




Rich Solvent

Lean Solvent

CO2 Capture System

Dashed lines indicate substitutability of rich and lean solvent sources.

66

When “charging” stored solvent, regenerate stored solvent by passing stored rich solvent to regenerator and storing resulting lean solvent.



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

67




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

68




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

69




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

70




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

71




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

72

Key parameter: reduction of net electricity provided to grid per ton of solvent stored during “charging”.



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

73

We allow venting emissions when “charging”, which allows generator to maintain constant fuel input and net electricity to grid.



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

Vented Flue Gas

74

Flexible CCS Coal Plant: Stored Solvent



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

Dashed lines indicate substitutability of rich and lean solvent sources.

75

When “discharging” stored solvent, capture CO2 with stored solvent, eliminating capacity and heat rate penalty of CO2 capture system.



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

76




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

77




Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

78

Key parameter: electricity provided to grid for each ton of stored lean solvent “discharged” per energy used to store lean solvent during “charging”.



Regenerator

Flue Gas

CO2 Absorber






Rich Solvent

Lean Solvent

CO2 Capture System

79

MISO Reserves

• Reserve requirements (Navid 2012):• Regulating (bidirectional): 400 MW• Spinning: 1,000 MW• Supplemental: 1,000 MW

Source: “Level 200 – Energy and Operating Reserves Markets.” MISO. 29 April 2014.

80

Continuous solvent electricity use parallels electricity output by base CCS generator.

6/1/20306/1/20306/2/20306/3/20306/4/20306/5/20300

100

200

300

400

500

600

700

BaseSS Discharge 1SS Discharge 2VentVent When ChargeCont. SolventPump Dummy 1Pump Dummy 2

Date

Elec

tric

ity G

ener

ation

(MW

h)

81

Total provide reserves by solvent storage discharge are almost constant.

6/1/2030 6/1/2030 6/2/2030 6/3/2030 6/4/2030 6/5/20300

20

40

60

80

100

120

140

160

180

200

Date

Tota

l Pro

vide

d Re

serv

es (M

W)

82

Supporting Slides Citations

• Navid, Nivad. “Reserve requirement identification with the presence of variable generation.” MISO. 26 April 2012. Presentation, UVIG Spring Technical Meeting.

Documents

Cost-Effectiveness of Flexible Carbon Capture and Sequestration for Complying with the Clean Power Plan Michael Craig Advisers: Paulina Jaramillo, Haibo