SLIDE 1
Fuel Cell and Electrolyser
½O2
H2 H2O
½O2 H2O + 2e- → H2 + O2- O2- O2- → 2e- +½O2 H2 + O2- → H2O + 2e- O2- ½O2 + 2e- → O2-
SOFC SOEC
H2 H2O H2 + CO + O2 H2O + CO2 + electric energy (∆G) + heat (T∆S)
SOFC SOEC
SOEC: Key enabling Technology for sustainable Fuels and Feedstocks - - PowerPoint PPT Presentation
SOEC: Key enabling Technology for sustainable Fuels and Feedstocks - - PowerPoint PPT Presentation
SOEC: Key enabling Technology for sustainable Fuels and Feedstocks John Bgild Hansen, Haldor Topse Presentation to NSF February 2, 2018 Fuel Cell and Electrolyser SOFC SOEC H 2 O H 2 H 2 H 2 O H 2 + O 2- H 2 O + 2e - H 2 O + 2e -
SLIDE 2
SLIDE 3
SOEC more efficient than present Electrolysers Internal waste heat used to split water
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 100 200 300 400 500 600 700 800 900 1000
Deg C. kWh per Nm3 H2 Minimum Electricity Input Waste heat which can be utilised to split water
Energy needed to evaporate water
SLIDE 4
SOEC Electrolysis
CO H2 CO2 Power Steam CO2 Hydrogen SNG Methanol DME Gasoline Diesel CO Syngas
SLIDE 5
Cell Development from 1989
Cell generations with ceramic support 3G metallic support
Ni/YSZ YSZ LSM YSZ or SSZ Ni/YSZ CGO LSCF LSCF CGO YSZ or SSZ FeCr
850 oC 600 oC 750 oC 1000 oC
Ni/YSZ YSZ LSM
1G 2.XG 2.5G Performance– Robustness – Cost reduction ESC ASC MSC
SLIDE 6
Development of stacks
Base case design: 75 cells 12x12 cm2 Design for robustness Design for manufacturability
Incremental development towards and industrial product TOFC Platform Stack
SLIDE 7
CO from CO2 by SOEC electrolytic process Commercially available – Biggest plant so far 250 kW
Production of oxygen-rich gas
+ 2 → + →
+ 2
Electrochemical reaction at the fuel electrode side
SLIDE 8
Biogas upgrade by means of SOEC
CH4 + CO2 + 3H2O + El 2CH4 +H2O + 2O2
SLIDE 9
CO2 + 4H2 ↔ CH4 + 2H2O (-∆H = 165 kJ/mol)
Syngas = SNG + heat Energy: 100% = 80% + 20%
SNG 100% 80% 20% Heat
SNG Technology
Methanation generates a lot of heat
SLIDE 10
Biogas to SNG via SOEC and methanation of the CO2 in the biogas:
SLIDE 11
Exergy Flows in CO2 case
SLIDE 12
Synergy between SOEC and fuel synthesis
SOEC Synthesis CO2 H2O Syn Gas Product Steam
SLIDE 13
Methanation and SOEC at Foulum
SLIDE 14
Production (100 % = 10 Nm3/h CH4) vs hours on stream. 3.1 kWh/Nm3 H2
0% 20% 40% 60% 80% 100% 120% 680 700 720 740 760 780 800 820 840 860 500 1000 1500 2000 2500
Percent of Design production
Hours on Electrolysis
SLIDE 15
Methanator catalyst very active and stable
SLIDE 16
Transient operation of methanator
SLIDE 17
Average gas compositions June 2, 2016
Position CH4 CO2 N2 H2 Inlet 56 43 1 Exit 1st stage 94.58 0.27 0.91 4.23 Product gas 97.69 0.00 0.95 1.36
SLIDE 18
Key numbers Denmark (2008)
¡ Final energy consumption: 673 PJ ¡ Biogas potential: 40 PJ ¡ If upgraded by SOEC: 67 PJ ~ 10 % ¡ NG used for power plants: 73 PJ ¡ NG used in household, industry and service: 76 PJ ¡ Saved CO2 ~ 1 MT/capita
SLIDE 19
Methanol synthesis
Ø CO + 2H2 = CH3OH + 91 kJ/mol Ø CO2 + 3H2 = CH3OH+H2O + 41 kJ/mol
SLIDE 20
Cu(111), d=0.21nm Cu(200), d=0.18nm ZnO(011), d=0.25nm ZnO(012), d=0.19nm Cu(111) Cu(111)
H2 H2/H2O
1.5mbar, 220oC 1.5mbar, H2/H2O=3/1, 220oC
The Active Site of Syngas Catalyst
Cu is metallic when catalyzing:
- WGS
- MeOH synthesis
- MeOH reforming
Catalyst dynamic:
- Number of active
sites depends on conditions
SLIDE 21
Conversion of methanol as function of CO2 content in stoichiometric gas
10 20 30 40 50 60 70 80 90 100 5 10 15 20 25 30
Percent CO2 in Carbon conversion %
J.B. Hansen Data Condensing methanol K.Klier Data Lab data 225 C
SLIDE 22
Methanol from CO2 and Steam
Water SOEC Oxygen CO2
Methan
- l
synthesis Separator
Methanol Purge Recycle
SLIDE 23
Space velocity and byproducts as function
- f CO2 converted in SOEC
100 200 300 400 500 20 40 60 80 100
Percent CO2 through SOEC Space velocity Relative %
100 400 700 1000 1300
Byproducts Relative %
Byproducts Space Velocity
SLIDE 24
Results of ”to pressurize SOEC stacks or not”
SOEC Pressure Syngas Comp, % CO2 Comp LHV Efficiency, % Atmospheric 6.8 0.1 75.8 @50 bar 0.0 1.9 79.5
- Max. theoretical
83-88
SLIDE 25
Heat of Reactions per mole H2 @ 280 ° C
Product From CO kJ/mol From CO2 kJ/mol Gasoline 79 37 CH4 72 44 DME 55 24 MeOH 50 20
Evaporation of 1 mol of water requires ~ 48 kJ @ 25 – 60 bar g NB: Steam conversion is only 70 – 80 % in SOEC plants
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Lifetime Reliability & Performance Cost
From SOEC Science to Commercial Product
Design
Processing
Materials
SLIDE 27
Energinet.dk’s vision for fossil fuel free Denmark in 2050 – The Wind Scenario
El- Transmission Gas Transmission
Peak Shave: Gas Turbine SOFC Catalysis: MeOH, DME Gasoline, SNG
District Heating
Gas System Storage
Upgrade To Methane
District Heating District Heating
SOEC Electrolysis Gasifier/ Digester Capture
Biomass Air Low priced
DH DH O2 Heat
High priced
Cleaning Compress
Green Synfuels
SLIDE 28
CEESA plan requires 4-8 GW electrolysis capacity needed for Denmark
SLIDE 29