Carbon Dioxide Emissions Associated with the Manufacturing of Tractors and Farm Machinery in Canada

The energy required to manufacture farm machinery is almost as high as the fossil fuel energy consumed during farm field work. A method is needed to quantify this indirect energy and to relate it to farm management decisions, particularly reduced tillage. In this analysis the Farm Fieldwork and Fossil Fuel Energy and Emissions (F4E2) model, which has successfully estimated energy used for farm field work, was used to estimate the annual replacement rate for tractors and related farm machinery, and the associated CO2 emissions. Although the number of tractors simulated by the F4E2 model fell short of the reported numbers of tractors in Canada for 1991 and 1996, the average size of the simulated tractors was reasonably close to the average from the tractors across Canada recorded during Agricultural Census surveys. Distributions of simulated and recorded tractors showed similar shapes. The model estimated the net CO2 emissions from manufacturing to be 3·6 Tg for 1996, which was within 2% of the estimate based on manufacturing energy derived from farm machinery expenditures. A simple index, also based on the F4E2 model, was used to extrapolate the 1996 national CO2 emission estimate to other Census years from 1981 to 2001 for use in Agri-environmental Indicators for Canada.