A study by Canadian scientists has found that diversified organic farm systems cut energy use by up to one-half. The research compared energy use on high-input conventional farms with reduced input conservation farming systems and organic systems. It found that total energy use was highest on the farms using high levels of inputs such as nitrogen fertiliser and pesticides, while energy use was 50% lower under organic management. According to the team, most of the energy savings came from the absence of conventional fertilisers on the organic farms.
The team kept detailed records of energy use for the three different systems across three crop rotations. In addition to the absolute levels of energy used, the research also calculated each system’s energy use efficiency, measured in terms of the amount of grain plus forage produced for each unit of energy input. Organic systems also came out highest on this this key performance metric, with 8.8 units of food energy harvested for each unit of energy needed to produce the crop. In comparison, on conventional, high-input farms, each unit of energy used in production yielded 7.1 units of food energy.
Source: European Journal of Agronomy