Large Fusion Power Plant Study L. M. Waganer, 18 Mar 2000 1 Results of Large Fusion Power Plant Study L. M. Waganer The Boeing Company and John Sheffield,

Large Fusion Power Plant Study

L. M. Waganer, 18 Mar 20001

Results of Large Fusion Power Plant

Study

L. M. WaganerThe Boeing Company

andJohn Sheffield, ORNL and JIEE - UT

William Brown, James Hilley, Thomas Shields, Duke Engr & ServicesGary Garret, Dennis McCloud, TVA

Joan Ogden, Princeton Univ

US/Japan Workshop on Fusion Power Plant Studies16-17 March 2000



Purpose of Study

This study is designed to evaluate effects on electrical utility system hardware, operations, and system reliability of incorporating large generation units (≥ 3 GWe).

Scope of Study

• What are the consequences of deploying large, single-unit power plants?•Would the use of co-generation, e.g., hydrogen, improve the prospects of deployment of large plants?



Impact Of Large Electrical Generating Plants

(> 1.5 GWe)If size exceeds maximum plant size on Utility system:

• Additional spinning and operational reserves are needed.

• Additional siting costs may be incurred to cover increased substation and transmission requirements.

• Utility production costs may increase due to production dispatch and operating modes of other generating plants.

0

1

2

3

4

5

6

1 2 3 4

Power Plant Output, GWe

Impact of Large Power Plants• Additional purchased power may be required during scheduled and unscheduled downtimes.



Co-generation of Hydrogen and Electricity Can Help Lessen Utility Impact

Benefit:Generate hydrogen during the night when demand (and POE) is low and electricity when demand (and POE) is high



Co-Generation Considerations

• Fusion power plant economics favors full power operation

• Co-generation lessens impact on electrical grid and allow load following

• Fusion plant can supply high or low temperature process heat to electrolyzers



Study Baseline Assumptions

• ARIES-AT was chosen as power plant to supply electricity and process heat

• Hydrogen would be produced with high temperature electrolysis (endothermic and exothermic) or conventional alkaline electrolyzers



Fusion Plant Design Basis

• Use ARIES-AT design (evolving from ARIES-RS)• Improve plasma physics modeling of Reversed Shear regime• Use SiC first wall and blanket structural material and LiPb/He

heat transfer media to enable exit temperatures of 1000 - 1100°C• Employ IHX and closed cycle helium gas turbine to yield thermal

efficiencies of 55% to 60%• Increase power core lifetime, reliability, and maintainability to

improve availability from 76% to 85+% • Employ low cost manufacturing techniques• Raise ARIES-AT plant capacity to 2 - 4 GW



COE Scaling for Advanced Tokamaks

COE Scaling to Plant Size xxx

0.00

10.00

20.00

30.00

40.00

50.00

60.00

0.00 1.00 2.00 3.00 4.00 5.00

Net Plant Output, GWe

ARIES-AT: ImprovedPerformance, Low CostComponents, 60% Efficiency,85% Availability



System Elements



Intercooler 1Intercooler 2

Compressor 1Compressor 2Compressor 3

Heat RejectionHX

WnetTurbine

Recuperator

Blanket

IntermediateHX

5'

1

2.A2.A'

389

47'

9'

10

6

T

S

1

2.A

3

4

5 6 7 8

9 10

Divertor(and FW)

LiPb blanketcoolant

He Divertor(and FW)coolant

Brayton Cycle for LiPb Blanket with He-Cooled Divertor andElectrolyzer Heat Exchanger

A. R. Raffray/September 23, 1999

11

11

Thermal Powerto Electrolyzer

Water

2.B

2.B

Low temperature process heat (150°C) is extracted after Brayton turbine. Less energy is available in recuperator. Hence, increasing hydrogen production decreases system efficiency



As More Thermal Power Is Used In Electrolyzer, Fusion Plant Efficiency Decreases

Effect of Variable Electrolyzer Power ss

0

500

1000

1500

2000

2500

3000

3500

0.00 0.20 0.40 0.60 0.80 1.00

Fraction of Power to Electrolyzer

Power toElectrolyzer

Power to Grid

Total Power



Feasibility Issues for Hydrogen Production• Competition is pushing the price of hydrogen down

– Steam reforming of natural gas ~ $5/GJ– Gasification of hydrocarbon fuels ~ $8/GJ– Comparison to $1/gal gasoline ~ $8/GJ

• Electrolyzer Plant Equipment adds ~ $3/GJ to the price of H2

• The remainder of the cost of hydrogen (COH) is directly proportional to the input COE

• As electrical demand grows and capacity is reduced, there will be no cheap off-peak electricity (10 to 30 mills/kWh)

• Fusion COE would have to be in the range of 30 mills /kWh to competitively produce hydrogen in today’s market

• If price of gasoline is $2/gal, hydrogen production with fusion would be competitive with COE values around 60 mills/kWh



Assessment Options and Trades• Dedicated Hydrogen Plant

– Plant size

• 1/2 Electricity (Peak) + 1/2 Hydrogen (Off-Peak) – Plant size– Peak electricity price– Electrolyzer cost– Electrolyzer efficiency– Conventional vs. HTE

• Off- Peak and On-Peak– Power split during On-Peak

0

100

Percent

0

100

Percent

0

100

Percent

0:00 06:00 12:00 18:00 24:00

75

Time of Day

H2Production

ElectricityProduction

Dedicated Hydrogen Production

Hydrogen Off-Peak, Electricity On-Peak

Hydrogen Off-Peak, Hydrogen + Electricity On-Peak

H2Production

H2Production

ElectricityProduction



HTE vs. Conventional ElectrolysisDedicated Hydrogen Production

Fusion Plant

5954 MWth

538 MWthof 150°C Steam

2869 MWe

High TempElectrolyzer,900°C, 3 bar,

η = 111 %

3185 MW H2( Enough H2 for a

7.4 )fleet of million cars

=Electrolyzer Capital Cost900/$ kWH2 3185 =x MW

2.87 $ billion

, High Temperature Electrolyzer Exothermic Operation

Fusion Plant

5954 MWth

3152 MWe

Conventional,Electrolyzer

70° , 1 ,C barη = 80 %

2521 MW H2( Enough H2 for a

5.9 )fleet of million cars

=Electrolyzer Capital Cost600/$ kWH2 2521 =x MW

1.51 $ billion

Conventional Alkaline Electrolyzer

Turbine Generator Turbine Generator



COH, Dedicated Production

0

5

10

15

20

25

30

35

0 500 1000 1500 2000 2500 3000 3500 4000 4500

Hi T Electrolyzer ARIES-AT

Conv. Electrol. $300/kW ARIES-AT

Conv. Electrol. $600/kW ARIES-AT

Co

st o

f H

ydro

gen

Pro

du

ctio

n (

$/G

J)

Fusion Power Plant Size (MWe)



Comparison of Electrolysis Types and Costs(50-50 H2/Electricity, On-Peak Price is 6 mills/kWh)

Cost of H2 from Off-peak Fusion Power ARIES-AT On-Peak Power Cost is 6 cents/kWh, f=0.5

0

5

10

15

20

25

0 1000 2000 3000 4000 5000

Fusion Power Plant Size (MW)

Cost

of

Hyd

rog

en

($/G

J)

f=.5, High Temp. Electrolysis

f=.5, Conventional Electrolysis,$600/kWH2

f=.5, Conventional Electrolysis,$300/kWH2



Comparison of On-Peak Electricity Price(50-50 H2/Electricity, Electrolyzer Cost $300/kWH2)

Cost of Electrolytic Hydrogen Production from Off-Peak Fusion Power:

Conventional Electrolysis $300/kWH2, ARIES-AT

0

2

4

6

8

10

12

14

16

18

20

0 500 1000 1500 2000 2500 3000 3500 4000 4500

Pon= 5 cents/kWh

Pon=6 cents/kWh

Pon=7 cents/kWh

Pon=8cents/kWh

Price of On-Peak Electricity

Co

st o

f H

ydro

gen

Pro

du

ctio

n (

$/G

J)




Variable On-Peak Electricity Production(On-Peak Price 6 mills/kWh, Electrolyzer Cost $300/kWH2)

H2 Production Cost for Various Operating Strategies:

Dedicated H2 Production; 50% On-peak and 100% Off-peak H2 production;

25% On-Peak and 100% Off-peak H2; Off-peak H2 Production Only

ARIES-AT , On-Peak Power Cost 6 cents/kWh, Conv. Electrolyzer $300/kWH2

0

5

10

15

20

25

0 500 1000 1500 2000 2500 3000 3500 4000 4500

Dedicated H2 production

50% On Peak H2 Production

25% On Peak H2 Production

Off-peak H2 Production (Conv.

Electrolysis=$300/kWH2)

Co

st o

f H

ydro

gen

Pro

du

ctio

n (

$/G

J)




COH Comparison with Other Sources

Cost of Hydrogen Production ($/GJ)

0

5

10

15

20

25

30

35

1 10 100 1000

Hydrogen Plant Capacity (million scf H2/d)

H2 C

ost

($./

GJ)

Steam reforming(NG=$3/MBTU)

Steam Reforming(NG=$6/MBTU)

Steam Reforming(NG=$6/MBTU, w/COseq.)Fusion Dedicated HTEARIES-AT

Fusion Off-Peak ARIES-AT

Biomass Gasification

Coal Gasification



Study Conclusions• Main H2 competitors are Biomass and Fossil (coal or

NG) gasification• Must use large fusion plants for economy of scale• Fusion plants must be affordable with high availability• COH is lower if subsidized by peak electricity

– Production COE must be lower than peak!

It may be possible for hydrogen from off-peak fusion power to compete with other low or zero CO2 options, but stringent cost and performance goals must be met and peak power must be valuable.



Some Comparative Data To Visualize Hydrogen Production and Water Usage

Food for thought: This production rate would supply enough hydrogen fuel for 20% of the cars in the LA basin if equipped with fuel cells. (Ref. J. Ogden) (~ 1.3 million cars)

Product Units Per Second Per Hour Per Day Per year

Nm3 7.935E+01 2.857E+05 6.856E+06 2.002E+09

Hydrogen scf 2.953E+03 1.063E+07 2.551E+08 7.450E+10

kg 7.242E+00 2.607E+04 6.257E+05 1.827E+08

GJ 1.014E+00 3.649E+03 8.757E+04 2.557E+07

Water kg 6.472E+01 2.330E+05 5.591E+06 1.633E+09

Documents

Large Fusion Power Plant Study L. M. Waganer, 18 Mar 2000 1 Results of Large Fusion Power Plant Study L. M. Waganer The Boeing Company and John Sheffield,