1. 1
The Future of
Renewable Gas
in Ireland

2. 2
Some Context ….
• Energy demand in Ireland has increased by 72% from 1991 to 2008 characterised by;
• The Renewable Energy targets are quite challenging;
– 40% of electricity to come from renewable sources by 2020
– 12% of heat to be derived from renewable sources by 2020
– Renewable resources to account for 10% of all transport fuel by 2020
• Ireland is making progress addressing RES (E);
– 11.8% of 2009 electricity consumption from renewable sources
• RES (H) and RES (T) progress towards targets have been slow to date;
– 3.6% of thermal energy and 1.2% of transport energy from renewable sources in 2008
• Landfill Directive
• Renewable gas produced from biomass using Anaerobic Digestion represents a significant and
under represented source of renewable energy in Ireland.

3. 3
Biogas is produced when feedstocks, such as organic
wastes, and energy crops, are converted into biogas
using anaerobic digestion technology

4. 4
Injection into the gas network may look like…
Substrat(s) Methanisation
Treatment
(CO2,H2S,
water, traces)
Raw biogas
• Bio waste
• Sewage
• Food -
processing waste
• …
Composition:
• 50 - 65%CH 4
• 30 - 40%CO 2
• water
• H2S
• NH3
• traces
Upgraded gas
Composition
similar to
natural gas
Control (CH 4,
CO2, water, H 2S)
Di
ge
sta
t
Odorisation
Regulator for flow /
pressure (2nd
compressor?)
Compression
(few bars)
Metering
Control of gas
quality
Injection point
Valve
Natural gasNatural gas + Biogas
Vent or
storage
If quality is not good enough!
Out of the limits
Safety equipments
(shut -off valve, safety
valve…)
Substrat(s) Methanisation
Treatment
(CO2,H2S,
water, traces)
Raw biogas
• Bio waste
•
• Food -
processing waste
• Energy crops…
Composition:
• 50 - 65%CH 4
• 30 - 40%CO 2
• water
• H2S
• NH3
• traces
Upgraded gas
Composition
similar to
natural gas
Process Control (CH4,
CO2, O2, H2S, H2O)
Digestat
Odorisation/ LPG*
Regulator for flow /
pressure (2nd
compressor?)
Compression
Metering
Control of gas
quality
Injection point
Valve
Natural gasNatural gas + Biogas
Vent or
storage
If quality is not good enough!
Out of the limits
Safety equipments
(shut -off valve, safety
valve…)

5. 5
Linkoping Sweden

6. 6
Feed stock for Linkoping
7,000t/a of pig
slurry
47,000t/a of
slaughter waste
Blood and process water
pumped in

7. 7
Biogas treatment
Collection over
digester
Scrubbing Compression
and storage

8. 8
65 buses, 10 waste collection lorries, 600
cars…

9. 9
And a train

10. 10
Biogas from grass as transport fuel in Salzburg
harvest
silage storage
macerator
Source: energiewerkstatt, IEA and persona photos
anaerobic digester
weigh bridge
Biogas service station

11. 11
Renewable Gas has a key role to play in a low carbon
future for Ireland
• Simple efficiency
measures across all
sectors
• Decarbonised
electricity fuels zero
emission cars
• Decarbonise gas using
renewable gas

12. 12
Opportunity– Renewable Heating
Biomethane for Heating
• Utilise the Bord Gáis gas network as a route to market for
renewable heating with biomethane (BioNG):
– Over 700,000 domestic and 30,000 I/C customers served
by the network.
– Uses existing meters (incl. Smart Meters when available).
– Minimal changes to supplier billing systems.
– No disruption to premises required – will allow customers
switch to renewable heating with a phone call!
– Used in existing appliances….. At very high efficiencies
– e.g. 80% for a gas boiler,
– as a renewable fuel source for domestic and I/C CHP
units).
– Increases national fuel diversity and security of supply.
– Significant contribution towards the RES-H target
possible.

13. 13
Opportunity- Renewable Transport
Biomethane for Transport
• Utilise the Bord Gáis gas network as a route to
market for renewable transport with biomethane
(BioCNG):
– Over 11 million cars worldwide running on
CNG incl. Germany, Italy.
– Bi-fuel cars and vans available – can switch
from petrol to CNG seamlessly at the push of
a button!
– Significant contribution towards the RES-T
target possible and reductions in national
CO2 levels.
– Proven vehicle and re-fuelling options
available today.

14. 14
Biomethane across Europe

15. 15
Potential for Renewable Gas in Ireland
Figures converted from PJ to mscm natural
Gas equivalent (@ 36.8 MJ/m³)
Practical
(mscm pa)
Agricultural Slurry 51
OFMSW 15.6
Slaughter Waste 18.6
Surplus Grass 325.7
Total 410
As % of total Irish gas demand 7.5%
• Notes:
• 1. 3,873,525 tonnes agricultural slurry x 12.8m3 methane (CH4) per tonne x 1/0.97= 51.3Mm3 biomethane per annum (with 97% CH4 content).
• 2. 870,000 tonnes OFMSW x 25% recoverable x 69 m3 CH4 per tonne x 1/0.97= 15.6 Mm3 biomethane per annum.
• 3. 208,877 tonnes slaughter waste x 86 m3 CH4 per tonne x 1/0.97= 18.6 Mm3 biomethane per annum.
• 4. 97,500 hectares x 3,240 m3 CH4 per hectare x 1/0.97 = 325.7 Mm3 biomethane per annum.
• 5. Conversion assumes biomethane has an energy content of 36.8 MJ/Mm3.

16. 16
Irish Renewable Targets
National Targets
• RES-E: 40% electricity from renewable sources by 2020.
• RES-H: 12% heating from renewable sources by 2020:
– Renewable energy accounted for 3.6% of thermal energy in 2008
– Bio methane could deliver 6.5% to this target
• RES-T: 10% renewable fuels for transport by 2020:
– Renewable energy accounted for 1.2% of transport energy in 2008
– Bio methane could exceed this target (12%)
• Source: SEI EPSSU Energy in Ireland Key Statistics 2009.

17. 17
The Cost of Producing Biomethane
Feedstock/scenario €/mn3
OFMSW (50,000 t/a) 0.14
Slaughter Waste (50,000 t/a) 0.73
Grass (137 ha, farm model) 0.97
Grass (137 ha, developer
model)
1.10
Co-digest (slurry & grass) 1.23
Slurry (29,700 t/a) 1.83
The Cost of producing Biomethane, Green Gas Technologies Ltd., March 2010

18. 18
Regional potential for grass
biomethane
• Assessment criteria
– Pasture area
– Grass yields
– Current farming practice
– Gas grid coverage
– Availability of belly grass
Source:
Determing the regional potential for a grass biomethane industry, Submitted
to Applied Energy, October 2010.

19. 19
Resource mapping
Source: EPA Corine Land Cover Data
Percentage
pasture
Grass yields,
gas grid &
slaughter-
houses

20. 20
Potential for grass
Grass biogas Grass biomethane Grass + belly grass biomethane

21. 21
Ballyhoura
Ballyhoura:
• Within an area of high
potential
• High pasture coverage
• Good gas grid coverage
• Good availability of belly
grass
Resource calculation:
• 20 km transport distance to
gas grid

22. 22
Ballyhoura: enough biomethane to heat
32,000 homes
Annual
feedstock
Biomethane
(Mmn3 yr-1)
Energy
(PJ yr-1)
Cars
(nr yr-1)
Houses
(nr yr-1)
Grass silage 261,727 ha 910.6 33.37 855,696 644,250
5% grass
silage
13,086 ha 45.5 1.67 42,785 32,213
Belly grass 5094 t
(20%DS)
0.3 0.01 316 238
Total (5%
grass + belly
grass)
45.9 1.68 43,101 32,450
Number of private cars in Limerick (city + county): 84,170
Number of meter points in Limerick (city + county): 25,366