Determination of power requirements and energyconsumption in dairy cattle farms

Global consumption of dairy products is projected to increase by 19% per capita by 2050. Milk production is an energy-intensive process. Therefore, along with concerns related to greenhouse gas emissions originating from agricultural activities, it is imperative that the expansion of milk production is accompanied with increased utilization of sustainable energy resources in order to ensure the economic and environmental sustainability of the dairy industry. Reducing energy costs and improving energy efficiency are crucial for both financial viability and environmental impact mitigation. However, before implementing the efficiency-enhancing measures, it is essential that the total energy consumption of all energy-consuming systems be evaluated. This study presents an analysis of the energy consumption in dairy cattle farms. Energy consumption in modern dairy farms is highly dependent on various technological components, including water heaters, milking machines, feed mixing systems, milk cooling tanks, and manure management systems. In this context, identifying the energy consumption patterns of machines used on a seasonal basis will facilitate the development of strategies for improvement, allowing for both a comprehensive assessment of the current situation and the implementation of measures to reduce the carbon footprint in future operations. This study was conducted in dairy farms affiliated with Akdeniz University (AKDÜ), Burdur Mehmet Akif Ersoy University (MAKÜ), and Isparta University of Applied Sciences (ISUBÜ), all located in the Western Mediterranean Region of Turkiye. The collected energy consumption data were analyzed in detail, and energy consumption profiles of the farms were established. Additionally, comparisons of energy consumption across different farms, seasons, and machine types were conducted. Energy consumption values were recorded for one week for irregularly operated machines, including water heaters (SIST), milking machines (SSM), and milk cooling tanks (SST). For regularly operated machines, including manure scrapers (GS), manure pumps (GP), manure mixers (GK), manure separators (GSP), animal cooling fans (HSF), and animal grooming brushes (HKF), measurements were taken for a complete cycle or period. During the measurements that lasted one week, employees conducting milking, feeding and maintenance operations in the barn were observed closely and labour times and procedures were recorded in detail. The milking times of dairy animals that entered the milking parlors as a group were measured from the beginning to the end of the milking period and the differences between the farms were statistically analyzed. The amount of milk (kg) entering the SST, the milk temperature inside the SST (°C), and the ambient temperature (°C) were recorded minute by minute throughout the milking period. Based on these measurements, time-dependent temperature and weight variation graphs of the milk stored in the SST were generated. Additionally, temperature readings were collected every five minutes from the hottest point of the vacuum pump, which is the exhaust outlet, to compare operational differences among farms. The recorded active energy consumption data were analyzed based on the daily number of lactating cows and the total milk yield. These calculations enabled the determination of unit energy consumption per lactating animal and per 1 kg of milk produced for different seasons and farm conditions. The research findings indicate that a significant part of energy consumption in dairy farms originates from water heaters, milking machines, and milk cooling systems. Additionally, newly developed animal cooling fans were found to account for a considerable share of energy consumption. During the winter trials, the daily energy consumption (kWh), energy consumption per lactating animal (kWh/head), and energy consumption per unit of milk produced (kWh/kg) were recorded as follows: 52.69 kWh, 0.99 kWh/head, and 0.044 kWh/kg for AKDÜ, 106.98 kWh, 2.42 kWh/head, and 0.083 kWh/kg for MAKÜ, and 48.56 kWh, 2.70 kWh/head, and 0.138 kWh/kg for ISUBÜ. In the summer trials, the corresponding values were 146.26 kWh, 3.37 kWh/head, and 0.176 kWh/kg for AKDÜ, 194.71 kWh, 3.51 kWh/head, and 0.121 kWh/kg for MAKÜ, and 48.11 kWh, 3.01 kWh/head, and 0.133 kWh/kg for ISUBÜ. The milk yields recorded during the winter season were 22.51 kg/head for AKDÜ, 29.23 kg/head for MAKÜ, and 19.56 kg/head for ISUBÜ, while during the summer season, the values were 19.17 kg/head, 29.06 kg/head, and 22.56 kg/head, respectively. In terms of active energy consumed per 1 kg of milk, AKDU had the lowest amount in the winter period and the highest amount in the summer period. The number of milked animals (heads), milk yield (average kg), and machine working hours (min.) are the factors that directly affect active energy consumption in dairy farms. Regular maintenance and repair of machines directly affect these consumption values. The machine-based energy consumption data obtained in this study can be used to investigate various energy saving and energy efficiency increasing mechanisms, such as the use of renewable energy sources. KEYWORDS: Dairy cattle breeding, Mechanization in animal production, Energy use in agriculture, Agricultural energy systems, Agricultural machinery systems.