Life-cycle greenhouse gas assessment of Community Supported Agriculture in California's Central Valley

Urban Farm DB summary

This case study assessed greenhouse gas (GHG) emissions from five Community Supported Agriculture (CSA) operations in the Sacramento Valley, California, collecting input, production and distribution data from each farm and reporting emissions in CO2e per 1 kg of CSA produce at the pickup location. Total emissions varied widely, ranging from 1.72 to 6.69 kg CO2e per kg of produce with an average of 3.94 kg CO2e, and electricity was the largest emissions source, contributing over 70% of total CO2e on average. Despite apparent similarities among the operations in production site, acreage, customer base and practices, there was still substantial variability in total GHG emissions. The study argues that the complexity of production and distribution systems means food systems cannot be reduced to a simple binary of local being better than conventional, or vice versa, though localized production systems that use less electricity (or renewable energy) and efficiently produced compost had lower GHG emissions than those that did not.