1. Estimation of On-Farm Greenhouse
Gas Emissions from Poultry Houses
C. S. Dunkley
Dept. Poultry Science
University of Georgia

2. Recent findings
Introduction
Chicken- 2.36 kg CO2e/kg of product
at farm gate
Beef- 14.8 kg CO2e/kg of product
at farm gate
Pork- 3.4-4.2 kg CO2e/kg of product
at farm gate (Pelletier, 2010)
(Pelletier et al., 2010)
(Pelletier, 2008)

3. 2 Studies
• Broiler Complex
– 627 houses were tested:
• Broiler- 87 farms, 538
houses
• Breeder- 15 farms, 55
houses
• Pullet- 7 farms, 34 houses
• Layer Complex
– 12 house in-line complex
• Upstream and downstream
emissions were not
considered

4. Inventory in Scopes
Scope 1
Scope 2
Scope 3

5. Data Collection and Evaluation
• Survey distributed to growers
• Survey questions included:
– Electricity usage
– Propane use
– Diesel oil use
– Age of house
– Construction of house
– Number of birds raised each year, etc.
– Refrigerant use
• GHG emissions estimated using IPPC spreadsheets
some of which were pre-populated with emission
factors.

6. Types of Emissions
• Mechanical
– Purchased Electricity
– Mobile machinery
– Stationary machinery
• Non-mechanical
– Enteric fermentation
– Manure management

7. Mechanical Emissions
• ~96% of GHG
emitted on
broiler and pullet
farms is from
propane use
• ~82% of GHG
emitted on
breeder farms is
from electricity
use
Results
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Broiler House Breeder House Pullet House
Stationary Combustion Transportation Fuel Purchased Electricity
CO2equivalent

8. Mechanical Emissions
• Avg. broiler house
emits ~790 tonne
CO2e
• Avg. breeder house
emits ~35 tonne
CO2e
• Avg. pullet house
emits ~448 tonne
CO2e
Results
tonnesCO2e/yr
0
100
200
300
400
500
600
700
800
900
Broiler House Breeder House Pullet House
Stationary Combustion Transportation Fuel Purchased Electricity

9. Non-Mechanical Emissions
0
20
40
60
80
100
120
140
Broiler Houses Breeder Houses Pullet Houses Layer Houses
50.96
32.78
46.49
138.97
8
32.53
15.25
42.91
N2O emissions CH4 Emissions
tonnesCO2e/yr

10. Manure management system
in laying Hen house

11. GHG Inventory- Broiler House
Emissions Categories
GHG Emissions (metric tonnes)
Base Period: 2009
CO2 CH4 N2O CO2e
Scope 1
Mechanical
Mobile Machinery 2.58 0.0004 0.00007 2.58
Stationary Machinery 764.91 0.0606 0.0012 766.783
Total 767.49 0.061 0.00127 769.363
Non-mechanical
Enteric fermentation - - -
Manure management - 0.32 0.1614 56.1
Total - 0.32 0.1614 56.1
Total Scope 1 767.49 0.381 0.16267 825.463
Scope 2
Purchased Electricity 21.52 0.0004 0.0004 21.54
Total Scope 2 21.52 0.0004 0.0004 21.54
Total Scopes 789.01 0.3215 0.16307 847.003
Total Mechanical 767.49 0.061 0.00127 769.363
Total Non-mechanical - 0.32 0.16267 56.1

12. Emissions Categories
GHG Emissions (metric tonnes)
Base Period: 2010
CO2 CH4 N2O CO2e
Scope 1
Mechanical
Mobile Machinery 45.675 0.00648 0.00117 46.174
Stationary Machinery 683.373 5.415 1.083 685.049
Total 728.448 5.421 1.084 731.223
Non-mechanical
Enteric fermentation - - -
Manure management - 20.6 5.7 2199.6
Total - 20.6 5.7 2199.6
Total Scope 1 728.448 26.012 6.78 3376.5
Scope 2
Purchased Electricity 1169.751 0.0199 0.0193 1176.152
Total Scope 2 1169.751 0.0199 0.0193 1176.152
Total Scopes 1 & 2 1898.199 26.22 6.98 4546.251
Scope 3
Users of refrigerant equipment 32.87
Total Scope 3 32.87
Total Scopes 4585.522
Total Mechanical 728.448 5.42 1.084 731.238
Total Non-mechanical - 20.6 5.70 2182.56
GHG Inventory- 12 House Laying Hen Complex

13. Reducing GHG emissions
• Reducing energy use
will also reduce the
amount of GHGs that is
emitted
• Reduction must to be
done on a farm by farm
basis
• Reduce propane use by
preventing heat loss;
– Enclose houses that are
not solid walls
– Insulate curtain
openings, walls and
ceiling

15. Reducing GHG emissions
• Reducing energy use
will also reduce the
amount of GHGs that is
emitted
• Reduction must to be
done on a farm by farm
basis
• Reduce propane use by
preventing heat loss;
– Enclose houses that are
not solid walls
– Insulate curtain
openings, walls and
ceiling

16. Emissions based on house age
0.00 200.00 400.00 600.00 800.00 1000.00 1200.00
5
10
20
24
647.86
1027.02
949.06
1027.26
Total GHG
Tonnes CO2 equivalents
Ageofhouseinyears

17. Four farms with similar age and
structure houses
0
200
400
600
800
1000
1200
1400
1600
1800
House 1 House 2 House 3 House 4
Diesel kwh Propane Total GHG
TonnesCO2e

18. Reducing GHG emissions
• Reducing energy use
will also reduce the
amount of GHGs that is
emitted
• Reduction must to be
done on a farm by farm
basis
• Reduce propane use by
preventing heat loss;
– Enclose houses that are
not solid walls
– Insulate curtain
openings, walls and
ceiling

19. Three houses with similar age but
different type of construction
0
500
1000
1500
2000
2500
Combination sides Curtain sided Solid walled
Diesel kwh Propane Total GHG
TonnesCO2e

20. Reducing GHG emissions- mechanical
• Use the attic area as a solar energy collector;
– Install attic outlets
• Use more efficient equipment such as;
– Fans, generators, lighting, heaters
• Maintenance of equipment;
– Clean fans
– Clean outlets/inlets
– Change fan belts as needed

21. Reducing GHG emissions- Manure
Management
1. Manure handled as a solid or spread on
land, decompose aerobically and produce little
or no CH4
2. Proper management of bedding (indoor) and
manure heaps (in storage sheds) will reduce
GHG emissions
• Avoid prolonged litter storage to reduce CH4 emissions
• Minimize compaction
• Frequent addition of litter
• Keep litter dry and covered from the elements

22. 1. Add nitrification inhibitors to reduce NH3 emissions
2. Addition of high carbon substrate to manure heaps
3. Compaction of manure heap to reduce aeration
4. N2O emission from poultry litter is higher than synthetic
fertilizer…but,
5. Applying poultry litter to agricultural fields off-sets 10%
energy use and 1% GHG emissions (Pelletier et al., 2010)
Reducing GHG emissions- Manure
Management

23. Research Opportunities
– Actual CH4 and N20 emissions from poultry houses
and stack houses
– Emissions from poultry litter application to crop
lands
– Carbon sequestration from poultry litter
application
– Emissions factors from enteric fermentation for
birds.