 Energy costs represent between 2% (at cattle feed lots) and 9% (for grain farming, due partly to grain drying) of farm production costs.In 2006 there were about 65,000 dairy farms in the United States, although most had fewer than 200 cows.One "resource auditor" believes it is possible for dairy farms to reach an energy usage of as low as 200 kWhr per cow per year although an analysis of California dairy farms found that 300 kWhr/year was the lowest actually attained.