Meat Eaters Guide: Methodology - Environmental Working Group

Meat Eaters Guide: Methodology
6. Eggs
The life cycle analysis for eggs is based on average emissions of a British Columbia large-scale freerange
operation and a New Jersey large-scale confined operation.
a. Key Production and Modeling Details
• Pullets are raised (from chicks born in hatcheries) for about 19 weeks until they reach layer
size and then transferred to a laying barn.
• A layer production cycle is 52 weeks, during which a single layer can produce about 25 dozen
eggs.
• Laying hens are replaced at the end of this productive cycle.
• Feed ration consists of soybean meal, corn and fishmeal.
• Other inputs include fuel for transportation of inputs and electricity for heating the hatchery
and the laying barn.
Table 21. Greenhouse Gas Emissions from Egg Production (at farmgate)
Egg production system kg of CO e per kg of edible eggs
2
British Columbia large-scale free range 2.38
New Jersey large scale confined 1.86
Average CO e emissions per kg of eggs 2 2.12
Table 22. Greenhouse Gas Emissions from Egg Consumption (post-farmgate)
Emission Source kg of CO e per kg of consumed eggs
2
Processing 0.29
Domestic Transport 0.37
Refrigeration (retail) 0.07
Home Cooking 0.23
Waste Disposal 0.22
Total 1.1863 Calculation for total overall Greenhouse Gas Emissions from Egg Production
b. Sources of GHG Emissions
36
Environmental Working Group Meat Eaters Guide: Methodology 2011