In order to evaluate energy efficiency in alfalfa production system was investigated by questionnaire of farmers in different farms in West Azerbaijan, Mahabad, Iran during 2005 to 2010 growing seasons. Energy efficiency was calculated by using of consumed data as inputs, total production as output, and their concern equivalent energy. The amount of energy and inputs used in the farms in 2005 was more than the next years and the highest energy production (output) and energy efficiency (output to input ratio) was obtained from the 2008, 2009 and 2010. Our results showed that, the highest energy consumption in the studied fields was due to irrigation, machinery and nitrogen fertilizer, respectively. Also, lowest value was related to planting and labor, respectively. Using new irrigation methods, such as sprinkler and drip irrigation, with using of combination machines, doing timely required temporal of tractor services and suitable management of cropping system such as representing a fit crop rotation and benefiting from legumes for biological nitrogen fixation, can reduce energy consumption in production.
