1. Renewable Gas Biomethane 4th October 2013 Alison Cartwright MSc, CEng, MIMechE

2. Summary Why Biomethane Support for biomethane What is biomethane
Injecting biomethane into the gas grid
Use of biomethane in vehicles
Current and future projects
Barriers and issues
Conclusions

3. Why Biomethane? UK total gas demand 750TWh
UK domestic gas demand approximately 300TWh/annum
Investment in insulation and efficient heating reduce to 200TWh/annum
7TWh/annum 2020 target for biomethane
Realistic biomethane MAX is 20TWh/annum – potenially 10% of UK domestic demand
Biomethane is a constant source of energy
Essential to the mix with bio SNG and Power to Gas
Closed loop with ‘waste to wheel’
Low CO2 - especially if waste food is used

4. Support for Biomethane
Renewable Heat Incentive
7.3p/kWh for injected biomethane into the gas grid
Ofgem group ‘Energy Market Issues for Biomethane’ (EMIB)
Expert group to address issues
Reduction in capital costs
European wide projects promoting biomethane and green gas funded by Intelligent Energy Europe
Biomaster
Green Gas Grids
Bio-methane regions

5. What is Biomethane? Kitchen Waste Commercial food waste Landfill
Sewage
Farm Wastes
Industrial Waste

6. Anaerobic Digestion

7. Biogas Composition Methane (CH4) 55 - 60% CO2 35 - 40% O2 0.1 – 0.4%
H2S – 2,000 ppm
H2O Biogas is saturated with water
Siloxanes Typically present in sewage derived biogas
To get biomethane into the grid, need to remove all H2S, most CO2 and dry the gas

8. Clean-up and Upgrade

9. Propane Addition
Increase the calorific value (CV) of biomethane to the same as that in the gas grid

10. Grid Entry Unit Measures quality and energy values
Entry Facility comprises the following:
Odorant storage and injection
Gas quality monitoring
Gas CV measurement
Gas flow measurement
Pressure control
Aim Total capex <£300k for this plant in 2013
Falling to < £150k by 2015

11. Biomethane as Vehicle Fuel
Typically 1 bar
250 bar
CNG-CBM Compressors
Storage Cascade
Dispenser
Supply from gas grid
Local Gas Grid Pipe x
0.02 bar
7 bar
Biogas supply from Anaerobic Digester
3 bar
Biogas Clean-up and upgrading plant
Odorant and gas quality
Propane Added
There are practical difficulties running vehicles directly on biomethane because AD production is constant, vehicle fill patterns very lumpy…..need to use the gas grid

12. With CNG it is not chicken and egg because of our £10 billion gas grid
Its entirely about the vehicles
We now have them and many more on the way

13. Didcot – UK’s First BtG Project
Anaerobic
Digesters
Propane Storage
Gas bag
Propane Injector
Telemetry
Energy & quality Measurement
H2S and Siloxane filters
Biogas upgrader
Flow of biogas m3/hr
First gas to grid on 3rd Oct 2010

14. Poundbury - Dorset Approximately 37,000 MWh injected p.a.
Electricity and gas injection
First injection 2012

15. Springhill (Vale Green) near Evesham
Approximately 37,000 MWh p.a.
Go live – August 2013

16. Future Biogas - Doncaster
Agricultural
Approximately 35,000 MWh p.a.
Go live Q4 2013

17. Barriers and Issues RHI uncertainty
No pre-accreditation
Minimum 18 month projects
No sight of incentive past April 2015
Degression possible if multiple large projects
German AD companies in financial difficulties due to cut in tariffs
Public perception of Anaerobic Digestion
Injection into the gas grid set up for large flows
Lengthy procedures in some areas

18. Conclusions
It has taken 7 years but the regime looks good – 40 projects in next 2 – 3 years is possible
UK has extensive gas grid and the full support of UK gas distribution network owners
3% of domestic customer gas supply by 2020 is a reasonable target
7TWh+ out of around 300 TWh demand (around 150 projects of 600 M3/hr biogas)
Biomethane project economics are attractive
Important to get capital costs down via competition and innovation
Green Gas Certificates
CNG for trucks and buses and CHP/District Heating for new housing
The biomethane market is set to grow, delivering significant benefits and helping meet 2020 targets – fuel of the future!