In order to study the distribution of electricity consumption throughout the day, 61 dairy cattle farms in Castille and León (74 ± 8,4 cows, 2.284 ± 265,2 l/day y 29,3 ± 0,91 l/cow and day) using different milking systems (herringbone, parallel, automatic milking system ?AMS?, rotary, round the shed and tandem) were audited for the energy consumption. Information on the type of farm and milking system, milk production, number of lactating animals, schedules? was recorded. Moreover, electricity consumption was measured using network analyzers located at the entrance of the farm. Electricity usage rates per litre of milk yielded or milking cow and hourly average consumption were calculated. Although electricity consumption was highly variable throughout the day, most of the systems showed a maximum peak at 8:00 am and another at 8:00 pm; the minimum peak occurred between 12:00 am and 6:00 pm Automatic milking systems have a constant electricity consumption throughout the day; however, this system together with round the shed system, have the highest consumption per cow. The time that milking system is running together with the capacity and power of cooling tank are the key factors to be considered to optimize electricity consumption.