1. Sub-department of Environmental Technology 06-0068 Energie uit water www.wetsus.nl www.ete.wur.nl prof.dr.ir. Cees J.N. Buisman KIVI/NIRIA 16 oktober 2006

2. Sub-department of Environmental Technology 06-0068 De wereldcapaciteit wordt overschreden

3. Sub-department of Environmental Technology 06-0068 Bio-energie op dit moment belangrijkste renewable Source IAE 2003

4. Sub-department of Environmental Technology 06-0068 Biomassa is geen schone brandstof Source: Exploring the future Shell International

5. Sub-department of Environmental Technology 06-0068 Primaire productie Suiker energie Primaire productie Acetaat energie Bio-energie acetaat ipv suiker

6. Sub-department of Environmental Technology 06-0068 Via acetaat is er veel meer energiepotentieel in biomassa Source SenterNovem 2003

7. Sub-department of Environmental Technology 06-0068 Schone conversie essentieel WET BIOMASS Hydrogen : 3 $ct/MJ Ethanol : 3 $ct/MJ Electricty: 2 $ct/MJ Methane: 1 $ct/MJ via acetate

8. Sub-department of Environmental Technology 06-0068 Elektriciteitsproductie uit Rioolwater Biobrandstofcel+ 2 kWh/kg COD Aërobe zuivering- 0,5 kWh/kg COD Anaërobe zuivering+ 0,9 kWh/kg COD

9. Sub-department of Environmental Technology 06-0068 COD = C hemical O xygen D emand Used to generalize all dissolved (bio)-oxidizable material in wastewaters. Value expresses the amount of oxygen needed to completely oxidize the (bio)-oxidizable material. Represents the amount of potential energy contained in the wastewater. COD

10. Sub-department of Environmental Technology 06-0068 Electrochemically Active Micro-organisms COD in Wastewater (e.g. fatty acids) e-e- e-e- e-e- e-e- e-e- e-e- e-e- BIOANODEBIOANODE Biological Anode Electrons

11. Sub-department of Environmental Technology 06-0068 Electrochemically Active Micro-organisms Bio-electrochemistry Source: http://www.geobacter.org

12. Sub-department of Environmental Technology 06-0068 Nano Wires Source Nature Reviews 2006

13. Sub-department of Environmental Technology 06-0068 Glucose:  C 6 H 12 O 6 + 6 H 2 O  6 CO 2 + 24 H + + 24 e - Acetic Acid:  CH 3 COOH + 2 H 2 O  2 CO 2 + 8 H + + 8 e - Sulfur:  S 0 + 4 H 2 O  SO 4 2- + + 8 H + + 6 e - Etc. These electrons are released at a high energy level! Electron production Biological anodes

14. Sub-department of Environmental Technology 06-0068 Biological Anode:  CH 3 COOH + 2 H 2 O  2 CO 2 + 8 H + + 8 e - Cathode:  2 O 2 + 8 H + + 8 e -  4 H 2 O Overall:  CH 3 COOH + 2 O 2  2 CO 2 + 2 H 2 O + electricity  In theory: ~1 Volt Example Acetic Acid Microbial Fuel Cell

15. Sub-department of Environmental Technology 06-0068 Microbial Fuel Cell Glucose/CO 2 (-0.41 Volt) Acetic Acid/CO 2 (-0.27 Volt) Energie Opbrengst Bacteriën O 2 /H 2 O (0.82 Volt) Bio-electricity (+1.02 Volt) Energy Consumption Bacteria I -0.5 I -0.4 I -0.3 I -0.2 I -0.1 I 0.0 I 0.1 I 0.2 I 0.3 I 0.4 I 0.5 I 0.6 I 0.7 I 0.8 I 0.9 I 1.0 Bio-Anode Cathode Biological Anode Potential (~ -0.2 Volt) Energy Consumption Bacteria (= Potential loss)

16. Sub-department of Environmental Technology 06-0068 Microbial Fuel Cell AnodeCathode e-e- e-e- COD CO 2 + H + O 2 + H + H2OH2O = Electrochemically Active MO H+H+ Air H2OH2O CO 2 Exhaust Wastewater (COD-rich) Effluent (COD-poor)

17. Sub-department of Environmental Technology 06-0068 Configurations

18. Sub-department of Environmental Technology 06-0068 Performance Perspectives  Power Density: 1000 W/m 3  Voltage: 0.5-0.7 Volt  Efficiency: ~60% Status  Power Density: ~100 W/m 3  Voltage: 0.2-0.6 Volt  Efficiency: 15-30% For comparison: conventional anaerobic treatment coupled to a gasmotor also produces approximately 1000 W/m 3.

19. Sub-department of Environmental Technology 06-0068 Bio electrochemie maakt grote stappen voorwaarts COMMERCIEEL INTERESSANT

20. Sub-department of Environmental Technology 06-0068 The next step ELECTRICITY MICROBIAL FUEL CELL CO 2 ASSIMILATES SOLAR ENERGY O2O2

21. Sub-department of Environmental Technology 06-0068 Biological Anode:  CH 3 COOH + 2 H 2 O  2 CO 2 + 8 H + + 8 e - Cathode:  8 H + + 8 e -  4 H 2 Overall:  CH 3 COOH + 2 H 2 O  2 CO 2 + 4 H 2  In theory: 0.14-0.22 Volt required  In practice:<0.5 Volt required Example Acetic Acid Biocatalysed Electrolysis

22. Sub-department of Environmental Technology 06-0068 Biocatalysed Electrolysis Glucose/CO 2 (-0.41 Volt) Acetic Acid/CO 2 (-0.27 Volt) Energie Opbrengst Bacteriën H+/H 2 (-0.42 Volt) Hydrogen production requires an input of electricity (-0.22 Volt) Energy Consumption Bacteria (= Potential loss) I -0.5 I -0.4 I -0.3 I -0.2 I -0.1 I 0.0 I 0.1 I 0.2 I 0.3 I 0.4 I 0.5 I 0.6 I 0.7 I 0.8 I 0.9 I 1.0 Biological Anode Potential (~ -0.2 Volt) Bio-Anode Cathode

23. Sub-department of Environmental Technology 06-0068 Biocatalysed Electrolysis AnodeCathode e-e- e-e- COD CO 2 + H + H+H+ H2H2 = Electrochemically Active MO H+H+ CO 2 H2H2 Power Supply Wastewater (COD-rich) Effluent (COD-poor)

24. Sub-department of Environmental Technology 06-0068 Configuration Power Supply Electrochemical Cell

25. Sub-department of Environmental Technology 06-0068 1 kg COD 2 kWh 1.6 m 3 H 2 Bio-electrochemical System

26. Sub-department of Environmental Technology 06-0068 Manure NL 675 MW (5.4% NL consumption) 4.6 billion m 3 H 2 (79 % car km NL) Sewage NL 160 MW (1.3 % NL consumption) 1.1 billion m 3 H 2 (19 % car km NL) Bio-electrochemical Processes Electricity and hydrogen from sustainable sources

27. Sub-department of Environmental Technology 06-0068 www.wetsus.nl www.ete.wur.nl