1. Solar Thermal Fuel Production Christian Sattler1, Hans Müller-Steinhagen2, Martin Roeb1, Dennis Thomey1, Martina Neises1 1 DLR Solar Research, Solar Chemical Engineering 2 Technical University of Dresden

2. Overview Reasons for solar thermal fuel production Two examples
SET-Plan
Powertrains for Europe
Concentrating Solar Systems
Solar Fuels short and long term applications
Processes
Projects and existing pilot plants
Summary and Outlook

3. Political view: SET-Plan (2007) European Strategic Plan for Energy Technology
Development of energy technologies plays a crucial role for climate protection and the security of the global and European energy supply
Goals of the EU until 2020 (20/20/20)
20% higher energy efficiency, 20% less GHG emission,, 20% renewable energy
Actions in the field of energy efficiency, codes and standards, funding mechanisms, and the charging of carbon emissions necessary
Significant research effort is necessary for the development of a new generation of CO2 emission free energy technologies, like
Offshore-Wind,
Solar
2nd generation Biomass
Goal of the EU until 2050: 80% less CO2 emissions than in 1990

4. Production-, Storage- and Infrastructure topics of the European Hydrogen and Fuel Cell JTI

5. Example for industrial view: „Powertrains for Europe“
2010 fact based analysis on a portfolio of power-trains by McKinsey & Company for:
Car manufacturers: BMW AG, Daimler AG, Ford, General Motors LLC, Honda R&D, Hyundai Motor Company, Kia Motors Corporation, Nissan, Renault, Toyota Motor Corporation, Volkswagen
Oil and gas: ENI Refining and Marketing, Galp Energia, OMV Refining and Marketing GmbH, Shell Downstream Services International B.V., Total Raffinage Marketing
Utilities: EnBW Baden-Wuerttemberg AG, Vattenfall
Industrial gas companies: Air Liquide, Air Products, The Linde Group
Equipment car manufacturers: Intelligent Energy Holdings plc, Powertech
Wind: Nordex
Electrolyser companies: ELT Elektrolyse Technik, Hydrogenics, Hydrogen Technologies, Proton Energy Systems
NGO: European Climate Foundation
GOs: European Fuel Cells and Hydrogen Joint Undertaking, NOW GmbH
Available online at:

6. Development of EU GHG emissions [Gt CO2e]

7. Three Power Trains FCEV, BEV, and PHEV were evaluated against ICEs in three scenarios, on three types of cars, small, medium and large covering 75% of the European Fleet

8. Results

9. Total EU car fleet, million vehicles

10. Hydrogen production – benchmark processes for solar technologies

11. Concentrating Solar Technologies

12. Energy Routes Solar Energy Heat Radiation Solar-thermal
Fossil Resources
Biomass PV
CO2
Heat
Synthetic Fuels
Mechanical Energy
Power
Thermochemistry
Electrolysis
Photochemistry
Hydrogen

13. Temperature Levels of CSP Technologies
Paraboloid: „Dish“
Solar Tower (Central Receiver System)
Parabolic Trough / Linear Fresnel
3500 °C
1500 °C
400 °C
150 °C 50 °C

14. Annual Efficiency of Solar Power Towers
R.Buck, A. Pfahl, DLR, 2007

15. Solar Towers, “Central Receiver Systems”
PS10+20, Sevilla, E
PSA CESA-1, Almería, E
Solar-Two, Daggett, USA
Solarturm Jülich, D

16. Principle of the solar thermal fuel production
Recourses
Natural Gas
Water, CO2
Solar Tower
Chemical
Reactor
Heat
Fuel H2
CO + H2
Industry
Transportation
Energy Converter
Fuel Cell
Transportation
Power Production

17. CO2 Reduction by solar heating of state of the art processes like steam methane reforming and coal gasification
CO2 Reduction 20 – 50%
kg/kg

18. Solar-receiver + power [MWth]
Efficiency comparison for solar hydrogen production from water (SANDIA, 2008)*
Process
T [°C]
Solar plant
Solar-receiver + power [MWth]
η T/C
(HHV)
η Optical
η Receiver
η Annual Efficiency
Solar – H2
Elctrolysis (+solar-thermal power) NA
Actual Solar tower
Molten Salt 700
30%
57%
83%
14%
High temperature steam electrolysis
850
Future
Solar tower
Particle 700
45%
76,2%
20%
Hybrid Sulfur-process
Future Solar tower
51%
76%
22%
Hybrid Copper Chlorine-process
600
Molten Salt
700
49%
23%
Nickel Manganese Ferrit Process
1800
Future Solar dish
Rotating Disc < 1
52%
77%
62%
25%
*G.J. Kolb, R.B. Diver SAND

19. Short-term CO2-Reduction: Solar Reforming

20. Steam and CO2-Reforming of Natural Gas
Steam reforming: H2O + CH4  3 H2 + 1 CO
CO2 Reforming: CO2 + CH4  2 H2 + 2 CO
Reforming of mixtures of CO2/H2O is possible and common
Use of CO2 for methanol production:
e.g. 2H2 + CO  CH3COH (Methanol)
Both technologies can be driven by solar energy as shown in the projects: CAESAR, ASTERIX, SOLASYS, SOLREF…

21. Solar Methane Reforming – Technologies
decoupled/allothermal
indirect (tube reactor)
Integrated, direct, volumetric
Source: DLR
Reformer heated externally (700 to 850°C)
Optional heat storage (up to 24/7)
E.g. ASTERIX project
Irradiated reformer tubes (up to 850°C), temperature gradient
Approx. 70 % Reformer-h
Development: CSIRO, Australia and in Japan; Research in Germany and Israel
Australian solar gas plant in preparation
Catalytic active direct irradiated absorber
Approx. 90 % Reformer-h
High solar flux, works only by direct solar radiation
DLR coordinated projects: Solasys, Solref; Research in Israel, Japan
Zu a: Advanced STEam Reforming In Heat EXchanger: Dampf-Reformierung bei 700 bis 850°C und 8 bar; 100kW Maßstab.
Zu b: at CSIRO: MUSTR MUlti Straight Tube Reformer SCORE Single Coiled Reformer Tube

22. Project Asterix: Allothermal Steam Reforming of Methan
DLR, Steinmüller, CIEMAT
180 kW plant at the Plataforma Solar de Almería, Spain (1990)
Convective heated tube cracker as reformer
Tubular receiver for air heating

23. “Indirect heated“ tube receiver: CSIRO Solargas
Indirect reactor technology
Second tower at the CSIRO Solar Centre Newcastle, NSW, Australia
Test facility for different Reactors
One will be the volumetric SOLREF reactor
Coordination by CSIRO, DLR is partner in an IPHE project

24. Direct heated volumetric receivers: SOLASYS, SOLREF (EU FP4, FP6)
Pressurised solar receiver,
Developed by DLR
Tested at the Weizmann Institute of Science, Israel
Power coupled into the process gas: 220 kWth and 400 kWth
Reforming temperature: between 765°C and 1000°C
Pressure: SOLASYS 9 bar, SOLREF 15 bar
Methane Conversion: max. 78 % (= theor. balance)
DLR (D), WIS (IL), ETH (CH), Johnson Matthey (UK), APTL (GR), HYGEAR (NL), SHAP (I)

25. Pilot plant for solar pet-coke reformig - SYNPET
500 kW SYNPET solar reactor
Plataforma Solar de Almería
Production: kg/h Synthesis gas
CIEMAT (E), ETH (CH), PDVESA (VEN)
T Denk et al., CIEMAT, 2009 25

26. Example: Possible sites in Algeria
Pipelines
Fields
kWh/m²/y
50 km distance to pipelines
Acceptable DNI
Available Land

27. Analysis of relevant Technologies for H2 Production (until 2020)NG
SMR
Solar-SMR
Grid Electricity
electrolysis
Wind
Biomass
H2 production cost 8*
€/GJ
12*
31 €/GJ
50-67 €/GJ
25-33 €/GJ
Positive impact on security of energy supply
modest
modest - high
high
Positive impact on GHG emission reduction
neutral - modest
negative -neutral
*assuming a NG price of 4€/GJ; NG Solar-SMR: expected costs for large scale, solar-only

28. Long-term: Water splitting processes

29. Promising and well researched Thermochemical Cycles
Steps
Maximum Temperature (°C)
LHV Efficiency (%)
Sulphur Cycles
Hybrid Sulphur (Westinghouse, ISPRA Mark 11) 2
900 (1150 without catalyst) 43
Sulphur Iodine (General Atomics, ISPRA Mark 16) 3 38
Volatile Metal Oxide Cycles
Zinc/Zinc Oxide
1800 45
Hybrid Cadmium
1600 42
Non-volatile Metal Oxide Cycles
Iron Oxide
2200
Cerium Oxide
2000 68
Ferrites
1100 – 1800
Low-Temperature Cycles
Hybrid Copper Chlorine 4
530 39

30. Process scheme of a metal oxide TCC*
1. Step: Water splitting
H2O + MOred  MOox + H2
MOox
MOred
H2O O2 H2
800 – 1200 °C
2. Splitting: Regeneration
MOred
MOox O2
MOox  MOred + ½ O2
1200°C
Net reaction: H2O  H2 + ½ O2
*Roeb, Müller-Steinhagen, Science-Mag., Aug

31. Pilotplant for solar water splitting by ferrites HYDROSOL 2
100 kW HYDROSOL 2 (EU FP6) Solarreaktor,
Plataforma Solar de Almería, Spanien
APTL (GR), CIEMAT (E), DLR (D), Johnsson Matthey (UK), STC (DK)
Concentration of hydrogen detected by GC
M. Roeb et al., DLR, 2009 31

32. Scale-up: 100kW-pilot-plant

33. Modelling of the pilot plant - Overview Modelling:
Modelling-Control
Software
(Labview®)
Parameter
Heliostatfield-
Simulation Tool
STRAL (C++)
Insulated Power (#1)
Parameter
Temperature
Model
(Matlab/Simulink®)
Temperature (#2)
Parameter
Hydrogen Production
Model
The simulation software has got four parts.
The model control software is responsible for the exchange between the three models.
The heliostat simulation tool is responsible for the flux distribution and the insulated power.
The temperature model calculates with the insulated power the temperatures in the reactor.
The hydrogen production model simulates the produced hydrogen.
With this model you can simulate a chemical plant with a solar tower system.
It can be used for online simulation and offline simulation for the analysis.
Hydrogen Amount (#3)

34. Modelling – Temperature model:
Collecting formulas of the heat flows (simplified balance!)
The first step for the control model is the collecting of the formulas for the heat flows in the reactor.
Heat flows in the process are heat radiation, heat conduction and convection.
This is only a simplified balance.
Heat flows: heat radiation, heat conduction and convection

35. Modelling – Temperature model:
First Verification of open loop control system
Regeneration
Input:
Simulated power East
Sampling rate (Sim.):
every second
Sampling rate (Exp.):
Every second
Average Deviation: 6.5%
Here one can see the simulated temperature in comparison with the measured average temperature on the eastern module.
You have to keep in mind that the simulated temperature has got the simulated power as input.
The measure and simulation cycle is every second.
I reached at the moment a mean error of 6,5%.
Production

36. Conclusion and Outlook

37. Future Solar Thermal Plants
Production of solar fuels (renewable H2 and CH4 / CH3OH), Recycling of CO2, Power production and Desalination (H2O) H2
Power
H2O
CH4, CH3OH
CO2
Desalinated Water
Heat
Sea water

38. Conclusion and Outlook
CO2 lean/free hydrogen is crucial for the energy economy no matter how the development will be
To achieve the energy/emission goals for 2020 promising renewable technologies like solar thermal must be implemented now, at the right places
Things to be done:
Secure and enhance the know-how by strong co-operations of industry and R&D
Close technological gaps
Transfer of the technology to industry
Provide technology for growing markets in solar regions

39. Acknowledgment
The Projects HYDROSOL, HYDROSOL II; HYTHEC, HYCYCLES, Hi2H2, INNOHYP-CA, SOLHYCARB and SOLREF were co-financed by the European Commission
HYDROSOL 3-D and ADEL are co-financed by the European Joint Technology Initiative on Hydrogen and Fuel Cells
HYDROSOL was awarded
Eco Tech Award Expo 2005, Tokyo
IPHE Technical Achievement Award 2006
Descartes Research Price 2006

40. Mahalo for your attention!