Potential of solid oxide electrolyser (SOEC) in PtG and PtL applications WP3: System integration, value chains, business cases

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1 Potential of solid oxide electrolyser (SOEC) in PtG and PtL applications WP3: System integration, value chains, business cases NEO-CARBON ENERGY 1ST RESEARCHERS SEMINAR Marjut Suomalainen, VTT

2 Solid oxide electrolyser (SOEC) High temperature electrolyser o C Atmospheric operation Research on pressurised operation conditions Presently at R&D stage Operating options 1. Steam electrolysis to produce hydrogen (H 2 ) 2. Co-electrolysis to produce syngas (CO+ H 2 ) Source: SBC Energy Institute Hydrogen based energy conversion 2

3 Benefits of SOEC compared to other electrolysers Potential for high electrical efficiency Possibility of co-electrolysis of H 2 O and CO 2 to produce syngas Reversible use as fuel cell to produce electricity from fuel Potential for low capital cost in the future due to less expensive materials (no noble metals) and high density Possibilities to increase energy efficiency due to heat integration with downstream processes 3

4 Constraints of SOEC compared to other electrolysers Poor lifetime 1 year proven at 17 % degradation rate Below 8 % annual degradation required before commercialisation Presently limited flexibility (constant load recommended to achieve better efficiencies) Presentlly high investment cost Ramping rate is unsure if kept warm start-up from cold takes hours Annual degradation SOEC Alkaline PEM today 17 (1) (1) Less than 8 % is required before commercialisation Source: SBC Energy Institute Hydrogen based energy conversion 4

5 Process possibilities downwards from SOEC Products from SOEC Hydrogen (H 2 ) Synthesis gas (CO + H 2 ) Further processing possibilities Methane (CH 4 ) Methanol (CH 3 OH) Dimethylether (DME) Liquid fuels Diesel by Fisher-Tropsch Gasoline from methanol 5

6 Business case potential related to SOEC 1. Fuel cell mode electrolyser mode 2. Continuous /intermittent operation (electricity from other sources when wind or solar not available) PtG or PtL 3. Co-electrolysis operation PtSNG or PtL 4. Smaller size applications due to high efficiency in small scale 5. Off-grid applications in remote locations

7 SOFC/SOEC operation SOFC SOEC Electricity Electricity Fuel (H2) Air SOFC Steam Depleted air Steam Air SOEC H2 Enriched air Can be combined into one device, solid oxide cells (SOC)

8 Syngas to methane/methanol Electricity for auxiliary components Heat Syngas from SOEC Upgrading process: Methanation/ methanol synthesis Synthetic natural gas /Methanol Condensate By-products (especially for MeOH synthesis: the products are usually sent to a burner)

9 Methanation Methanol synthesis Main reactions involved: +3 + = = = 41.2 Temperature range in the reactors: C Pressure in the process: bar Main reactions involved: + 2. = = 40.9 Temperature range in the reactors: C Pressure in the process: bar

10 Methanol to gasoline (MTG) Electricity for auxiliary components Heat Liquefied Petroleum Gases (LPG) Methanol Upgrading process: Methanol to gasoline Gasoline Condensate

11 Methanol to gasoline (MTG) Main reaction involved 2 + Multi step reaction; Exothermic; Temperature range in the reactors: C Pressure in the process: bar

12 SOEC manufacturers in Europe Sunfire (Germany) German project : demonstration plant SOEC 10 kwel Sofcpower (Italy) EU project Sophia Small scale proof of principle (SOEC size 3 kwel) combined to solar energy source Haldor Topsoe (Denmark) Danish project: Bio-SOEC Economic feasibility calculation of upgrading biogas to methane using SOEC 12

13 Sunfire: PtL demo plant 150 kwel + SOEC Project in Germany Start-up in preparation Hydrogen from SOEC, CO 2 from various sources, Fisher-Tropsch process Electrical effieciency to fuel estimated in advance to be around 70 % Source: Sunfire Closing the energy cycle. 13

14 Sofcpower: EU project Sophia Solar integrated pressurised high temperature electrolysis Small scale proof of principle (SOEC size 3 kw el ) combined to solar energy source Partners: HyGear B.v, Sofcpower SPA, Htceramix SA, CEA, DLR, EPFL, CDF Suez, VTT Project manager at VTT Olivier Thomann Total budget 6 M A 3 kw el pressurised HTE system coupled to a concentrated sola energy source will be designed, fabricated and operated on-sun Proof of principle 14

15 Economical feasibility Presently investment costs of SOEC systems high (like solid oxide fuel cells) Production rate of systems s is small Capital cost /kw does not decrease significantly when the scale increases Cost estimates are based on the futuristic, decreased capital costs based on increased production rates SOEC Alkaline PEM System investment cost today $/kw(hhv of H2) projected $/kw (HHV of H2) 212 (1) (2) (1) Expected at mass production (500 MW/a) (2) Expected at mass production Source: SBC Energy Institute Hydrogen based energy conversion 15

16 SUMMARY SOEC is at R&D phase High potential due to Possible to achieve high electrical efficiency No noble metals and high density -> possible to attain low capital costs in mass production Constraints Immature technology Too high degradation rate (less than 8 % is needed before commercialisation) Potential if the main challenges will be solved Degradation Investment costs 16

17 NEO-CARBON ENERGY project is one of the Tekes strategic research openings. The project is carried out in cooperation between VTT, Lappeenranta University of Technology and University of Turku / Futures Research Centre.