Solid Oxide electrolysis hydrogen production, Peter V. Hendriksen
Solid Oxide electrolysis hydrogen production, Peter V. Hendriksen
Solid Oxide electrolysis hydrogen production, Peter V. Hendriksen
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<strong>Solid</strong> <strong>Oxide</strong> Electrolysis Hydrogen <strong>production</strong><br />
<strong>Peter</strong> Vang <strong>Hendriksen</strong><br />
Fuel Cells and <strong>Solid</strong> State Chemistry Division, Risø DTU
Outline<br />
• Principle, what is <strong>electrolysis</strong> ?<br />
• SOEC<br />
• Thermodynamics<br />
• Economy<br />
• Technology status<br />
• Durability<br />
• Upscale (Unit sizes, <strong>production</strong> capacity)<br />
• Example of research activities<br />
• Summary<br />
2<br />
Risø DTU, Danmarks Tekniske Universitet
Routes to <strong>hydrogen</strong><br />
Today<br />
• From Hydrocarbon sources (NG) via syn-gas<br />
• (Electrolysis, industrial applications on site)<br />
In Future<br />
• Fermentation, gasification<br />
• Coal gasification (with CO 2 capture).<br />
Fossil<br />
Biomass<br />
Fossil<br />
CHEAP<br />
• Electrolysis<br />
• Alkaline<br />
• PEM<br />
• SOEC<br />
• Thermochemical watersplitting<br />
• Photolysis<br />
• Sulphur-iodine cycle<br />
Electricity, Wind<br />
Heat, solar<br />
SUSTAINABLE<br />
3<br />
Risø DTU, Danmarks Tekniske Universitet
Electrolysis, principle of operation (SOEC)<br />
Electricity + Heat<br />
Chemical energy<br />
Anode:<br />
Katode:<br />
Oxygen electrode<br />
2O 2- → O 2 + 4e -<br />
O 2<br />
+<br />
2O 2-<br />
2H 2 O 2H 2<br />
Fuel electrode<br />
2H 2 O + 4e - → 2H 2 + 2O 2-<br />
2CO 2 + 4e - → 2CO + 2O 2- 2CO 2 2CO<br />
÷<br />
4 e -<br />
<strong>Solid</strong> electrolyte<br />
Electrolyte Ox. electrode H 2 electrode Temp.<br />
Y 0.16 Zr 0.84 O 2 (La,Sr)MnO 3 Ni/Y 0.16 Zr 0.84 O 2 800 o C<br />
4<br />
Risø DTU, Danmarks Tekniske Universitet
Ni-YSZ supported cell (“2.0G”)<br />
Ni/YSZ support<br />
Ni/YSZ electrode<br />
LSM-YSZ electrode<br />
10 µm Acc. voltage: 12 kV SE image<br />
• Manufacturing techniques
Thermodynamics<br />
300<br />
H 2 O → H 2 + ½O 2<br />
1.55<br />
Energy demand (KJ/mol)<br />
250<br />
200<br />
150<br />
100<br />
50<br />
Liquid<br />
Gas<br />
Total energy demand (∆ H f )<br />
1.30<br />
1.04<br />
0.78<br />
0.52<br />
0.26<br />
1/(2·n·F) · Energy demand (Volt)<br />
E cell = E tn<br />
0<br />
0 100 200 300 400 500 600 700 800 900 1000<br />
Temperature (ºC)<br />
0.00<br />
Energy (“volt”) = Energy (kJ/mol)/2F<br />
E tn = ∆H/2F<br />
i ∝ E cell - ∆G/2F<br />
Price ∝ 1/i [A/cm 2 ] ,<br />
η = ∆H/∆G > 1 , η = 100 % at E = E tn (no heat loss)
Hydrogen by <strong>electrolysis</strong> for transport sector<br />
Is this an interesting option ?<br />
• FC vehicle has twice (?) the efficiency of the ICE vehicle<br />
• FC vehicles may have ranges like ICE vehicle<br />
• Transport from sustainable resources<br />
• Market: Many small plants. Good entry point<br />
7<br />
Risø DTU, Danmarks Tekniske Universitet
Economical analysis<br />
10<br />
Price of electricity<br />
Other assumptions<br />
SOEC system cost 0.15 €/cm 2<br />
200$/kW*<br />
Electricity price (¢/kWh)<br />
8<br />
6<br />
4<br />
2<br />
DK Electricity Price in 2010<br />
Average Price<br />
Heat<br />
Cell voltage (H 2 O)<br />
Cell voltage (CO 2 )<br />
0.23 ¢/kWh<br />
1.3 V (Vtn)<br />
1.5 V (Vtn)<br />
Current density 1.5 A/cm 2<br />
Expected life time<br />
Interest rate 5%<br />
10 years<br />
Expected CO 2 cost 23€/ton<br />
0<br />
0 2000 4000 6000 8000<br />
Expected H 2 O cost 2.3 €/ton<br />
Hours<br />
Source; S. H. Jensen, S. Ebbesen, K. V. Hansen, A. H. Pedersen #<br />
and M. Mogensen, ”Cost Estimation of H2 and CO Produced by<br />
Steam and CO2 Electrolysis”, 2011, (Unpublished).<br />
8<br />
Risø DTU, Danmarks Tekniske Universitet<br />
*J. Thijssen, U.S. DOE/NETL 2007
Economical analysis<br />
H 2 <strong>production</strong> cost (€/kg)<br />
2<br />
1<br />
0<br />
Heat 1%<br />
Water2%<br />
Investment<br />
Electricity<br />
12%<br />
85%<br />
0.3 €/cm 2<br />
0.15 €/cm 2 18<br />
0 2000 4000 6000 8000<br />
9<br />
0<br />
H 2 <strong>production</strong> cost (¢/Nm 3 )<br />
86<br />
43<br />
0<br />
Equiv. crude oil (€/barrel)<br />
Electrolysis activity (hours)<br />
Source; S. H. Jensen, S. Ebbesen, K. V. Hansen, A. H. Pedersen #<br />
and M. Mogensen, ”Cost Estimation of H2 and CO Produced by<br />
Steam and CO2 Electrolysis”, 2011, (Unpublished).<br />
• Oil price today ~ 79 $/barrel<br />
• Centralized methanol <strong>production</strong>, break even at ~ 110 $/barrel<br />
• AEC, H 2 <strong>production</strong> cost 1.85 €/kg Source; Final Report “Green SynFuels”, 2011<br />
9<br />
Risø DTU, Danmarks Tekniske Universitet<br />
EUDP 64010-0011<br />
Source; Project Report<br />
“planSOEC”, ForskEL2010,<br />
2010-1-10432
SOFC Technology status<br />
• Large development projects, 1990 -<br />
(Risø DTU, Haldor Topsøe A/S)<br />
2001-2011 Transfer of technology to TOFC<br />
History from 2002 to 2008<br />
20000<br />
100<br />
# 12x12 cm 2 cells produced -<br />
15000<br />
10000<br />
5000<br />
0<br />
2002 2003 2004 2005 2006 2007 2008<br />
Year<br />
75<br />
50<br />
25<br />
0<br />
Success rate for 12x12 (%) - line<br />
Risø DTU, Technical University of Denmark
New Topsoe Fuel Cell pilot plant<br />
• Inaugurated spring 2009<br />
• Production for development,<br />
test and market introduction<br />
• 5 MW per year capacity (for demos)<br />
• Full scale plant in 3-5 years
From cells to stacks<br />
• Each fuel cell gives a voltage of ~ 0.8 volt. To attain<br />
useful voltages several cells, e.g. 50, are stacked in<br />
series<br />
• High energy density: Stack electric power density of<br />
2.5 kW/liter demonstrated with by Topsoe - Risø DTU<br />
cell stacks<br />
• Scalable technology:<br />
From kW to MW
SOEC, Cell performance, Process is reversible<br />
World record !<br />
S. H. Jensen et al. , International Journal of Hydrogen Energy,<br />
Volume 32, Issue 15, 2007, P. 3253<br />
Risø DTU, Danmarks Tekniske Universitet
Technology status, SOEC<br />
Degradation of standard SOFC operated as <strong>electrolysis</strong> cells<br />
– With Clean inlet gasses:<br />
– No degradation at low current density (up to -0.75 A/cm 2 at 850ºC)<br />
Cell voltage (mV)<br />
1125<br />
1100<br />
1075<br />
1050<br />
1025<br />
1000<br />
975<br />
950<br />
925<br />
900<br />
850°C, -0.25 A/cm 2<br />
0 100 200 300 400 500 600<br />
Electrolysis time (h)<br />
H 2 O <strong>electrolysis</strong><br />
CO 2 <strong>electrolysis</strong><br />
Co - <strong>electrolysis</strong><br />
H 2 O + CO 2<br />
S. Ebbesen et al; Journal of The Electrochemical Society, 157 10 B1419-B1429 2010
Status at stack level<br />
Few (~ 7) experiments only<br />
Standard TOFC stack (SOFC stack, 2.0G cells) operated as both H 2 O and co<strong>electrolysis</strong><br />
13.0<br />
-0.50 A/cm 2 -0.75 A/cm 2<br />
Stack voltage (V)<br />
12.5<br />
12.0<br />
11.5<br />
11.0<br />
0 200 400 600 800 1000 1200<br />
Electrolysis time (h)<br />
No degradation at low current density (up to -0.75 A/cm 2 at 850ºC)<br />
The Danish National Advanced Technology Foundation’s advanced technology platform<br />
“Development of 2nd generation bioethanol process and technology”,S. Ebbesen et al. Int. J. of Hydrogen Energy 36, 2011
New SOFC cell types tested for <strong>electrolysis</strong> durability<br />
• A TOFC 10-cell stack with three classes of SOFC cells is being tested currently<br />
– 800 °C, -0.75 A/cm 2 , co-<strong>electrolysis</strong> (45%CO 2 -45%H 2 O-10%H 2 ), 1000 hr.<br />
– 2.5* G cells improved over 500 hr. !!<br />
– “2.1 G” cells and “MTC-cells” showed mild degradation<br />
16<br />
Source: M. Chen ForskEL2010, Energinet.dk 2010-1-10432
Electrolysis, Comparison of technologies<br />
Type Maturity Current density Other Advantages<br />
AEC Proven<br />
LT-PEM H 2 at pressure<br />
SOEC CO 2 /H 2 O <strong>electrolysis</strong><br />
HT-PEM HT heat<br />
Documented lifetime<br />
1/Price<br />
• SOEC: Cheap materials, No noble metals, Low volume<br />
• Winner : ???? Determined by price per Nm 3 /hr over lifetime at right scale and time<br />
17<br />
Risø DTU, Danmarks Tekniske Universitet
Electrolysis, Comparison of technologies<br />
Type<br />
Largest<br />
system<br />
Commercial<br />
suppliers<br />
Danish companies<br />
tanks/day<br />
AEC<br />
3.5 MW<br />
Norsk Hydro<br />
Hydrogenics<br />
Iht,….<br />
Green Hydrogen<br />
Siemens Corp. Tech. (DK)<br />
500<br />
LT-PEM<br />
45 kW<br />
H-TEC systems<br />
Hydro,…<br />
IRD<br />
SOEC<br />
15 kW<br />
Haldor Topsøe A/S<br />
TOFC<br />
2 !<br />
HT-PEM W<br />
Tantaline<br />
18<br />
Risø DTU, Danmarks Tekniske Universitet<br />
Elektrolyse<br />
5/10-2011
Status and Challenges<br />
Status<br />
• 20 kW SOFC deomstrated Wartsila/TOFC<br />
• 100 kW SOFC deomstrated (1996) Westinghouse<br />
• 250 kW design projects stated in Europe and US<br />
• TOFC <strong>production</strong> line 5 MW/year<br />
65 tanks per day<br />
20 units<br />
• Scale relevant for early demonstration (?)<br />
• Durability at 0.75 A/cm 2 looks promising (1000 hour test, SOFC 10.000 hours)<br />
• Economy (SOEC <strong>electrolysis</strong>) looks promising<br />
Challenges<br />
• Fast scale up needed<br />
• Large risk (FC Vehicle vs E-Vehicle vs synthetic sustainable fuels)<br />
• Demonstrate reliability and lifetime<br />
• Improve power density<br />
• Demonstrate pressurized operation<br />
19<br />
Risø DTU, Danmarks Tekniske Universitet
Acknowledgement<br />
Sponsors<br />
Danish Energy Authority<br />
• Energinet.dk<br />
• EU<br />
• Topsoe Fuel Cell A/S<br />
• Danish Programme Committee for Energy and<br />
Environment<br />
• Danish Programme Committee for Nano Science<br />
and Technology, Biotechnology and IT<br />
Colleagues:<br />
M. Mogensen, S. Ebbesen, A. Hauch, S. Højgaard Jensen, X. Sun, M. Chen, C. Graves,<br />
J. V. T. Høgh, K. Agersted Nielsen, Y. L. Liu, J. U. Nielsen + many many more
Status and Challenges<br />
• Scale relevant for early demonstration (?)<br />
• Durability at 0.75 A/cm 2 looks promising<br />
• Economy (SOEC <strong>electrolysis</strong>) looks promising<br />
• SOFC technology is a very good starting point for SOEC technology<br />
Challenges<br />
– Fast scale up needed<br />
– Large risk (FC Vehicle vs E Vehicle vs synthetic sustainable fuels)<br />
– Demonstrate reliability and lifetime<br />
– Improve power density<br />
– Demonstrate pressurised operation<br />
• Further information<br />
http://www.<strong>hydrogen</strong>net.dk/<br />
Report: “Pre-Investigation of Water Electrolysis”, PSO-F&U 2006-1-6287<br />
Report: “plan SOEC” ForskEL 2010-1-10432
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