Results of Large Fusion Power Plant Study

1
Results of Large Fusion Power Plant Study

• L. M. Waganer
• The Boeing Company
• and
• John Sheffield, ORNL and JIEE - UT
• William Brown, James Hilley, Thomas Shields, Duke
  Engr Services
• Gary Garret, Dennis McCloud, TVA
• Joan Ogden, Princeton Univ
• US/Japan Workshop on Fusion Power Plant Studies
• 16-17 March 2000

2
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?

3
Impact Of Large Electrical Generating Plants(gt
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.

Additional purchased power may be required
during scheduled and unscheduled downtimes.
4
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
5
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

6
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

7
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 - 1100C
• 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

8
COE Scaling for Advanced Tokamaks
9
System Elements
10
Low temperature process heat (150C) is extracted
after Brayton turbine. Less energy is available
in recuperator. Hence, increasing hydrogen
production decreases system efficiency
11
As More Thermal Power Is Used In Electrolyzer,
Fusion Plant Efficiency Decreases
12
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
  todays market
• If price of gasoline is 2/gal, hydrogen
  production with fusion would be competitive with
  COE values around 60 mills/kWh

13
Assessment Options and Trades
Dedicated Hydrogen Production

• 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

100
H
2
Percent
Production
0
Hydrogen Off-Peak, Electricity On-Peak
100
H
Electricity
2
Percent
Production
Production
0
Hydrogen Off-Peak, Hydrogen Electricity On-Peak
100
75
H
Percent
2
Electricity
Production
Production
0
2400
000
0600
1200
1800
Time of Day
14
HTE vs. Conventional Electrolysis
Dedicated Hydrogen Production
15
COH, Dedicated Production
35
30
25
Hi T Electrolyzer ARIES-AT
20
Conv. Electrol. 300/kW ARIES-AT
Conv. Electrol. 600/kW ARIES-AT
Cost of Hydrogen Production (/GJ)
15
10
5
0
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Fusion Power Plant Size (MWe)
16
Comparison of Electrolysis Types and Costs(50-50
H2/Electricity, On-Peak Price is 6 mills/kWh)
17
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
20
18
16
14
Price of On-Peak Electricity
12
Pon 5 cents/kWh
Pon6 cents/kWh
10
Pon7 cents/kWh
Pon8cents/kWh
Cost of Hydrogen Production (/GJ)
8
6
4
2
0
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Fusion Power Plant Size (MWe)
18
Variable On-Peak Electricity Production(On-Peak
Price 6 mills/kWh, Electrolyzer Cost 300/kWH2)
25
20
Dedicated H2 production
15
50 On Peak H2 Production
25 On Peak H2 Production
Cost of Hydrogen Production (/GJ)
10
Off-peak H2 Production (Conv.
Electrolysis300/kWH2)
5
0
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Fusion Power Plant Size (MWe)
19
COH Comparison with Other Sources
20
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.
21
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)