Energy use and Green house gas emission in organic agriculture

Summary

Reduction of fossil energy use has a two-fold aim namely reducing the dependence of a limited, non-renewable resource and reduction of emissions of green house gasses (GHG). Consumers interested in reducing their carbon footprint from food consumption may consider whether a shift towards eating organic foods will do the job? This involves two questions: Is organic food more energy efficient and –given that one is dedicated to eating organic – which products and which producers results in a lower GHG emission. From a farmer perspective it is interesting to know how the carbon footprint of the production may be reduced. Over time the principles for organic agriculture has included specific references to the question of reducing the use of non-renewable energy (Woodward & Vogtman, 2004) and this is still an explicit part of the objectives of the Danish organic farming movement.
It is, however, questionable to which degree these objectives have been achieved as regards the dependence on fossil energy in the present form of organic agriculture. The majority of farms still depend on fossil energy for traction and electricity and energy self-reliance seems not to be a major concern in practice. As regards fossil energy use, the major difference to conventional farming is that the rejection of chemical fertilizer reduces the indirect energy use in organic farming and that the yields are lower, thus reducing the solar energy captured in crops. However, as regards the emission of GHG the picture is more diverse and the net GHG emissions can be lower in organic agriculture compared with conventional.
The aim of this paper is thus to discuss the different perspectives of reducing energy use and GHG emissions from organic agriculture by presenting results regarding
· Different methods and results of comparison of energy use efficiency in organic agriculture
· The potential for energy savings and self-reliance in organic agriculture
· The relative importance of fossil energy use for emissions of GHG from production of different organic products
· The relative importance of different organic and conventional food items for the total GHG emission of food consumption